Merge dev into main - version 1.4.4

v1.4.3 — Multi-Account Support, Contact Improvements, and Settings Encryption

.env.example

@@ -67,6 +67,17 @@ JMAP_SERVER_URL=https://your-jmap-server.com
 # For Docker, mount a persistent volume at this path.
 # SETTINGS_DATA_DIR=./data/settings
 
+# =============================================================================
+# Server Listen Address
+# =============================================================================
+
+# Hostname the server binds to (default: 0.0.0.0)
+# Set to "::" for dual-stack
+# HOSTNAME=0.0.0.0
+
+# Port the server listens on (default: 3000)
+# PORT=3000
+
 # =============================================================================
 # Logging
 # =============================================================================
@@ -78,10 +89,27 @@ JMAP_SERVER_URL=https://your-jmap-server.com
 # LOG_LEVEL=info
 
 # =============================================================================
-# Login Page Customization (all optional)
+# Branding (all optional)
 # =============================================================================
 
-# Custom logo images for the login page (PNG, SVG, etc.)
+# Custom favicon for the browser tab.
+# Supported formats: SVG (recommended), PNG, ICO.
+# Recommended size: 32×32px minimum, 512×512px maximum (or SVG for best scaling).
+# Can be an absolute URL or a path relative to the public/ directory.
+# Defaults to the Bulwark favicon if not set.
+# FAVICON_URL=/branding/my-favicon.svg
+
+# Custom logos for the sidebar (shown in the main app after login).
+# Supported formats: SVG (recommended), PNG, WebP.
+# Recommended size: min 24×24px, max 128×128px
+# Can be absolute URLs or paths relative to the public/ directory.
+# If not set, no logo is shown in the sidebar.
+# APP_LOGO_LIGHT_URL=/branding/my-logo-color.svg
+# APP_LOGO_DARK_URL=/branding/my-logo-white.svg
+
+# Custom logo images for the login page.
+# Supported formats: SVG (recommended), PNG, WebP.
+# Recommended size: min 32×32px, max 512×512px
 # Can be absolute URLs or paths relative to the public/ directory.
 # Light mode logo (shown on light backgrounds), defaults to Bulwark logo.
 LOGIN_LOGO_LIGHT_URL=/branding/Bulwark_Logo_Color.svg

CHANGELOG.md

@@ -1,5 +1,84 @@
 # Changelog
 
+## 1.4.4 (2026-03-19)
+
+### Features
+
+- **Calendar**: Implement CalDAV discovery API with automatic calendar home resolution for multi-account setups
+- **Calendar**: Enhance calendar management settings with mailbox role reassignment controls
+- **Email**: Add signature rendering utilities with HTML-to-text conversion and sanitization
+
+### Fixes
+
+- **Auth**: Fix account session handling to update existing accounts instead of duplicating entries
+- **Auth**: Fix logout redirects and unauthenticated home page rendering
+- **Calendar**: Fix duplicate calendar edits and prevent double-save submissions in event modal
+- **Calendar**: Remove stale calendar ID references in favor of CalDAV-discovered IDs
+- **Contacts**: Improve RFC 9553 compliance for contact birthdays and address formatting
+- **Email**: Fix email signature rendering for identity signatures
+- **Folders**: Improve mailbox role management by clearing roles from all mailboxes before reassigning
+
+## 1.4.3 (2026-03-19)
+
+### Features
+
+- **Auth**: Implement multi-account support with up to 5 simultaneous accounts and instant switching
+- **Auth**: Add account switcher component with connection status, default account selection, and per-account logout
+- **Auth**: Support multi-account OAuth and basic auth with per-account session persistence
+- **Contacts**: Enhance contacts sidebar with collapsible sections, bulk operations, and address book grouping
+- **Contacts**: Add contact import functionality and keyword filtering
+- **Settings**: Add per-account encrypted settings storage with server-side sync support
+
+### Fixes
+
+- **UI**: Adjust popover alignment in sub-address helper component
+- **Settings**: Improve error logging in settings sync functionality
+
+## 1.4.2 (2026-03-19)
+
+### Features
+
+- **Calendar**: Add task list view for calendar tasks with task details and management
+- **Calendar**: Add shared calendar grouping with visual separation in sidebar
+- **Calendar**: Support double-click to create events and improve modal date handling
+- **Contacts**: Add address book directories with drag-and-drop and editor picker
+- **Email**: Add email attachment support in sendEmail functionality
+- **Email**: Implement draft editing functionality across email components
+- **Email**: Implement unwrapping of embedded message/rfc822 attachments with enhanced HTML body validation
+- **Email**: Add email export/import localization keys for multiple languages
+- **Contacts**: Update gender handling to use speakToAs structure
+
+### Fixes
+
+- **Email**: Resolve default sender to canonical identity on local-part login
+- **Email**: Refactor overflow handling in EmailViewer to use hidden priorities and layout effects
+- **Email**: Remove debugMode usage from EmailViewer component
+- **Calendar**: Enhance IMIP invitation and cancellation handling for calendar events
+- **Calendar**: Add time-based sorting for events in buildWeekSegments function
+- **Dependencies**: Update dompurify to 3.3.3 and elliptic to 6.6.1, add undici override
+
+## 1.4.1 (2026-03-18)
+
+### Features
+
+- **Security**: Add S/MIME certificate management with identity bindings, signer auto-import, unlock controls, and compose/viewer sign, encrypt, decrypt, and verification flows
+- **Email**: Add TNEF (`winmail.dat`) parsing to extract message bodies and attachments from Outlook rich-text emails
+- **Email**: Add archive organization modes for archiving directly or into year/month subfolders
+- **Email**: Add an "Always Show Emails in Light Mode" preference to avoid dark-mode conversion issues
+- **Email**: Apply the 12-hour or 24-hour time format preference consistently across calendar and email surfaces
+- **Identity**: Add identity refresh behavior in the identity manager so server-side changes stay in sync after edits
+- **UI**: Add configurable sidebar apps with custom icons plus inline or new-tab launch modes
+- **Branding**: Add runtime branding options for custom favicon, sidebar logos, and login logos
+- **Deployment**: Add configurable server listen address support via `HOSTNAME`, including IPv6 and dual-stack guidance
+
+### Fixes
+
+- **Calendar**: Improve all-day event handling
+- **Calendar**: Validate and default persisted calendar view mode values
+- **UI**: Use configured app names more consistently in metadata and login branding surfaces
+- **Docker**: Correct `HOSTNAME` formatting in the Docker Compose example
+- **Metadata**: Correct package author and container vendor metadata
+
 ## 1.3.0 (2026-03-16)
 
 ### Features

Dockerfile

@@ -13,7 +13,7 @@ LABEL org.opencontainers.image.description="Modern webmail client built with Nex
 LABEL org.opencontainers.image.source="https://github.com/bulwarkmail/webmail"
 LABEL org.opencontainers.image.url="https://github.com/bulwarkmail/webmail"
 LABEL org.opencontainers.image.licenses="AGPL-3.0-only"
-LABEL org.opencontainers.image.vendor="root.cloud"
+LABEL org.opencontainers.image.vendor="rbm.systems"
 
 WORKDIR /app
 ENV NODE_ENV=production

README.md

@@ -12,7 +12,7 @@ A modern, self-hosted webmail client for [Stalwart Mail Server](https://stalw.ar
 Built with Next.js and the JMAP protocol.
 
 [![License: AGPL v3](https://img.shields.io/badge/license-AGPL%20v3-blue.svg)](LICENSE)
-[![Version](https://img.shields.io/badge/version-1.2.4-green.svg)](CHANGELOG.md)
+[![Version](https://img.shields.io/badge/version-1.4.3-green.svg)](CHANGELOG.md)
 [![Docker](https://img.shields.io/badge/docker-ghcr.io%2Fbulwarkmail%2Fwebmail-blue)](https://ghcr.io/bulwarkmail/webmail)
 
 </div>
@@ -99,12 +99,14 @@ Built with Next.js and the JMAP protocol.
 - **Attachments** — upload, download, and inline preview
 - **Search** — full-text with JMAP filter panel, search chips, cross-mailbox queries, wildcard support, and OR conditions
 - **Batch operations** — multi-select with checkboxes, archive, delete, move, tag
+- **Archive modes** — archive directly or organize archived mail by year or month
 - **Print** emails directly from the viewer
 - **Color tags/labels** and star/unstar
 - **Virtual scrolling** for large mailboxes
 - **Quick reply** from the viewer
 - **Sender avatars** — favicon-based with negative caching for performance
 - **Recipient popover** for quick contact interaction
+- **TNEF support** — extract Outlook `winmail.dat` message bodies and attachments automatically
 - **Folder management** — create, rename, delete folders with icon picker and subfolder support
 - **Tag counts** — unread and total counts displayed in sidebar
 
@@ -151,6 +153,7 @@ Built with Next.js and the JMAP protocol.
 
 - **External content blocked** by default — trusted senders list for auto-load
 - **HTML sanitization** via DOMPurify with XSS prevention
+- **S/MIME** — manage certificates, sign outgoing mail, encrypt to recipients, decrypt messages, and verify signatures
 - **SPF/DKIM/DMARC** status indicators
 - **OAuth2/OIDC with PKCE** for SSO (Keycloak, Authentik, or built-in), with OAuth-only mode
 - **TOTP two-factor authentication**
@@ -163,12 +166,13 @@ Built with Next.js and the JMAP protocol.
 
 - **Three-pane layout** — sidebar, email list, viewer with resizable columns
 - **Dark and light themes** with intelligent email color transformation
+- **Always-light email rendering** option for problematic HTML messages in dark theme
 - **Responsive** — desktop sidebar + mobile bottom tab bar with tablet support
 - **Keyboard shortcuts** — full navigation without a mouse
 - **Drag-and-drop** email organization between mailboxes and tag assignment
 - **Right-click context menus**, toast notifications with undo, form validation with shake feedback
-- **Customizable toolbar** position and login page branding
+- **Customizable toolbar** position, custom favicon, sidebar/login logos, and login page branding
-- **Configurable logo** with light/dark mode variants
+- **Sidebar apps** — pin custom tools to the navigation rail and open them inline or in a new tab
 - **Settings sync** — preferences synchronized with the server (encrypted)
 - **Storage quota** display
 - **Shared folders** — multi-account access
@@ -183,6 +187,7 @@ Automatic browser detection with persistent preference.
 ### Identity Management
 
 - **Multiple sender identities** with per-identity signatures
+- **Identity refresh** — keep the identity manager aligned with server-side changes after edits
 - **Sub-addressing** — `user+tag@domain.com` with contextual tag suggestions
 - **Identity badges** in viewer and email list
 
@@ -243,6 +248,16 @@ APP_NAME=My Webmail
 
 All variables are **runtime** — Docker deployments can be configured without rebuilding.
 
+<details>
+<summary>Server Listen Address</summary>
+
+```env
+HOSTNAME=0.0.0.0    # Default; use "::" for IPv6
+PORT=3000            # Default listen port
+```
+
+</details>
+
 <details>
 <summary>OAuth2/OIDC (SSO)</summary>
 

ROADMAP.md

@@ -1,301 +0,0 @@
-<div align="center">
-
-<picture>
-  <source media="(prefers-color-scheme: dark)" srcset="public/branding/Bulwark%20Logo%20with%20Lettering%20White%20and%20Color.svg" />
-  <source media="(prefers-color-scheme: light)" srcset="public/branding/Bulwark%20Logo%20with%20Lettering%20Dark%20Color.svg" />
-  <img src="public/branding/Bulwark%20Logo%20with%20Lettering%20Dark%20Color.svg" alt="Bulwark Webmail" width="220" />
-</picture>
-
-</div>
-
-# Bulwark Webmail - Roadmap
-
-This document tracks the development status and planned features for Bulwark Webmail.
-
-## Completed Features
-
-### Core Infrastructure
-
-- [x] Next.js 16 with TypeScript and App Router
-- [x] Tailwind CSS v4 with Oxide engine
-- [x] Zustand state management
-- [x] Custom JMAP client implementation (RFC 8620)
-
-### Authentication
-
-- [x] Login with JMAP server authentication
-- [x] Session management (no password storage for security)
-- [x] Username autocomplete with history
-- [x] Logout functionality
-- [x] Authentication error handling
-- [x] JMAP identities for sender address
-- [x] TOTP two-factor authentication (Stalwart-compatible)
-- [x] OAuth2/OIDC with PKCE (opt-in SSO, session persistence, RP-initiated logout)
-- [x] External IdP support via explicit issuer URL (Keycloak, Authentik, etc.)
-- [x] "Remember me" session persistence for Basic Auth (AES-256-GCM encrypted httpOnly cookie)
-
-### JMAP Server Connection
-
-- [x] Session establishment and keep-alive
-- [x] Connection error handling and retries
-- [x] CORS error detection with actionable user guidance
-- [x] Session URL origin rewriting (fixes Docker/reverse proxy deployments where server returns internal hostname)
-- [x] Storage quota display
-- [x] Server capability detection
-- [x] Shared folders support (multi-account access)
-
-### Email Operations
-
-- [x] Email fetching and display
-- [x] Full HTML email rendering
-- [x] Compose, reply, reply-all, forward
-- [x] Draft auto-save with discard confirmation
-- [x] Mark as read/unread
-- [x] Star/unstar emails
-- [x] Delete and archive
-- [x] Color tags/labels
-- [x] Full-text search
-- [x] Advanced search with JMAP filter panel, search chips, and cross-mailbox queries
-- [x] Attachment upload and download
-- [x] Batch operations (multi-select)
-- [x] Quick reply form
-- [x] Email threading (Gmail-style inline expansion)
-
-### Real-time Updates
-
-- [x] EventSource for JMAP push notifications
-- [x] State synchronization
-- [x] Email arrival notifications
-- [x] Real-time unread counts
-- [x] Mailbox change handling
-
-### User Interface
-
-- [x] Three-pane layout (sidebar, list, viewer)
-- [x] Minimalist design system
-- [x] Dark and light theme support
-- [x] Custom scrollbars
-- [x] Mobile responsive design
-- [x] Keyboard shortcuts
-- [x] Drag-and-drop email organization
-- [x] Right-click context menus
-- [x] Hierarchical mailbox display
-- [x] Email list with avatars and visual hierarchy
-- [x] Expandable email headers
-- [x] External content warning banner
-- [x] SPF/DKIM/DMARC status indicators
-- [x] Loading states and skeletons
-- [x] Smooth transitions and animations
-- [x] Infinite scroll pagination
-- [x] Virtual scrolling for large email lists
-- [x] Error boundaries
-- [x] Settings page with preferences
-- [x] Navigation rail (desktop vertical icon sidebar + mobile bottom tab bar)
-- [x] Welcome banner for first-time users (one-time display, localStorage persistence)
-- [x] Confirmation dialog component with promise-based useConfirmDialog hook
-- [x] Toast notifications with undo action support and typed durations
-- [x] Inline form validation with shake animation (email composer, contact form)
-- [x] Login UX polish (error shake, discreet 2FA toggle, password visibility toggle, session expired banner)
-- [x] Empty state patterns for contacts (distinct "no data" vs "no search results" with contextual actions)
-- [x] WCAG AA reduced-motion media query (global animation/transition reset)
-- [x] Safe area inset utilities for notched devices
-- [x] Screen reader live region announcements (sr-only)
-
-### Internationalization
-
-- [x] English language support
-- [x] French language support
-- [x] Japanese language support
-- [x] Spanish language support
-- [x] Italian language support
-- [x] German language support
-- [x] Dutch language support
-- [x] Portuguese language support
-- [x] Automatic browser language detection
-- [x] Language preference persistence
-
-### Security & Accessibility
-
-- [x] External content blocked by default
-- [x] HTML sanitization with DOMPurify
-- [x] User control for loading external content
-- [x] Trusted senders list for automatic image loading
-- [x] Dark mode email readability (intelligent color transformation)
-- [x] WCAG 2.0 Level AA color contrast compliance
-- [x] Newsletter unsubscribe support (RFC 2369)
-- [x] XSS attack prevention with comprehensive validation
-- [x] CSP Report-Only headers with per-request nonce
-- [x] Security headers (X-Content-Type-Options, X-Frame-Options, Referrer-Policy, Permissions-Policy)
-- [x] Reusable focus trap hook (Tab cycling, Escape handling, focus restore)
-- [x] WCAG AA prefers-reduced-motion support (global animation/transition reset)
-- [x] Safe area insets for notched mobile devices
-- [x] Screen reader sr-only live region for dynamic announcements
-
-### Identity Management
-
-- [x] Multiple sender identities (name, email, signature)
-- [x] Sub-addressing support (user+tag@domain.com)
-- [x] Per-identity signatures
-- [x] Identity badges in email viewer and list
-- [x] Tag suggestions based on context
-- [x] Display name included in From header (recipients see name, not just email)
-- [x] Primary identity (matching login) selected by default in composer
-
-### Address Book & Contacts
-
-- [x] Contact store with JMAP sync and local fallback
-- [x] Contact CRUD operations (create, read, update, delete)
-- [x] Contacts list view with search/filter
-- [x] Contact details view/edit form
-- [x] JMAP contacts sync (RFC 9553/9610 ContactCard/AddressBook)
-- [x] Email autocomplete from contacts
-- [x] Contacts integration in email composer (To/Cc/Bcc)
-- [x] Contact groups/lists management with JMAP members map
-- [x] vCard import/export (RFC 6350 parser/generator, duplicate detection)
-- [x] Bulk contact operations (multi-select, delete, group add, export)
-- [x] i18n support for contacts (all 8 languages)
-
-### Vacation Responder
-
-- [x] JMAP VacationResponse singleton management
-- [x] Settings tab with date range and message configuration
-- [x] Sidebar indicator when vacation auto-reply is active
-- [x] i18n support (all 8 languages)
-
-### Calendar Integration
-
-- [x] JMAP Calendar types (RFC 8984) and client methods
-- [x] Calendar capability detection (urn:ietf:params:jmap:calendars)
-- [x] Calendar store with Zustand (persist middleware)
-- [x] Month, week, day, and agenda views
-- [x] Event modal (create/edit/delete with recurrence, reminders)
-- [x] Mini-calendar sidebar with calendar visibility toggles
-- [x] Calendar settings (default view, week start, time format)
-- [x] Multi-day event spanning across all covered days
-- [x] Column-based overlap layout for concurrent events
-- [x] Locale-aware date formatting via next-intl
-- [x] First day of week and time format settings wired to views
-- [x] Push notification handling for calendar state changes
-- [x] Calendar page capability check (redirect if unsupported)
-- [x] Error handling with toast feedback on event CRUD
-- [x] Timezone auto-detection on event creation
-- [x] Input validation, color sanitization, focus trap
-- [x] ARIA grid roles and event card accessible labels
-- [x] Mobile touch targets (44px minimum)
-- [x] Calendar keyboard shortcuts (m/w/d/a views, t today, n new event)
-- [x] i18n support with ICU pluralization (all 8 languages)
-- [x] Drag-and-drop event rescheduling (week/day time snap, month date move)
-- [x] iCalendar (.ics) file import via CalendarEvent/parse with preview and bulk create
-- [x] Event notifications with client-side alert evaluation and toast display
-- [x] Notification sound, acknowledged alert persistence (localStorage), proactive 24h event fetch
-- [x] Configurable notification settings (enable/disable, sound toggle)
-- [x] Participant scheduling with iTIP invitations (organizer/attendee UI, RSVP buttons, contact autocomplete)
-- [x] Inline calendar invitation banner in email viewer (auto-detect .ics attachments, RSVP, import to calendar, cancellation display)
-- [x] Scheduling message support (sendSchedulingMessages flag for create/update/delete)
-- [x] Click-drag to create events (pointer-based time range selection, 15-min snap, visual overlay)
-- [x] Event resize by dragging bottom edge handle (15-min snap, optimistic JMAP update)
-- [x] Recurring event edit/delete scope dialog (this event / this and following / all events)
-- [x] Double-click quick event creation (inline title input, PT1H default)
-- [x] Event duplication button in modal (clones event +1 day, opens for editing)
-
-### Email Filters
-
-- [x] JMAP Sieve Scripts (RFC 9661) with capability detection
-- [x] Visual rule builder (conditions: From/To/Cc/Subject/Header/Size/Body, actions: Move/Copy/Forward/Mark read/Star/Label/Discard/Reject/Keep/Stop)
-- [x] Raw Sieve script editor with syntax validation
-- [x] Sieve generator and parser with JSON metadata round-trip
-- [x] Filter store with CRUD, reorder, toggle, auto-save with rollback
-- [x] Opaque script detection with reset to visual builder option
-- [x] Focus trap accessibility in modals
-- [x] Toast validation feedback for empty rules
-- [x] Push notification handling for SieveScript state changes
-- [x] i18n support (all 8 languages)
-
-### Email Templates
-
-- [x] Reusable email templates with local storage persistence
-- [x] Category organization (General, Business, Personal, Support, Follow-up, custom)
-- [x] Dynamic placeholder variables with auto-fill from composer context
-- [x] Template manager modal (create, edit, duplicate, delete)
-- [x] Template picker in composer toolbar with search and category filter
-- [x] Custom placeholder prompt on template insertion
-- [x] Settings tab for template management
-- [x] Keyboard shortcut (Ctrl+Shift+T to insert template)
-- [x] i18n support (all 8 languages)
-
-### Email Display
-
-- [x] Proper email layout without horizontal scroll or clipping
-- [x] Blocked image container collapsing (no empty spaces in newsletters)
-
-### Testing
-
-- [x] Unit tests for validation utilities (57 tests)
-- [x] Unit tests for email sanitization (27 tests)
-- [x] Unit tests for color transformation (40 tests)
-- [x] Unit tests for contact store (56 tests)
-- [x] Unit tests for JMAP contact client (41 tests)
-- [x] Unit tests for vCard parser (18 tests)
-- [x] Unit tests for thread utilities (20 tests)
-- [x] Unit tests for email headers (39 tests)
-- [x] Component tests (contacts, UI components — 41 tests)
-- [x] JMAP client method tests (identity: 20, contacts: 41)
-- [x] Unit tests for Sieve generator (50 tests)
-- [x] Unit tests for Sieve parser (14 tests)
-- [x] Unit tests for calendar alerts (36 tests)
-- [x] Unit tests for calendar notification store (8 tests)
-- [x] Unit tests for calendar invitation parsing (25 tests)
-- [x] Unit tests for calendar participants (26 tests)
-- [x] Unit tests for template utilities (48 tests)
-- [x] Unit tests for OAuth PKCE and discovery (14 tests)
-- [x] XSS attack vector testing
-- [x] Playwright E2E framework setup
-
-### Deployment
-
-- [x] Runtime environment variables (Docker-friendly configuration)
-- [x] Health check endpoint
-- [x] Docker support (multi-stage build, docker-compose, standalone output)
-- [x] Structured server-side logger (text/JSON format, configurable level)
-- [x] Pre-built Docker image on [Docker Hub](https://hub.docker.com/r/bulwarkmail/webmail) and [GHCR](https://ghcr.io/bulwarkmail/webmail) with multi-arch support (amd64/arm64)
-- [x] GitHub Actions CI/CD for automated image publishing on releases
-- [x] CVE remediation: remove npm from production image, upgrade Alpine packages
-- [x] Server-side update check (logs newer version availability on startup)
-
-## Planned Features
-
-### Advanced Features
-
-- [ ] Free/busy queries (Principal/getAvailability)
-- [ ] Calendar sharing UI (JMAP Sharing RFC 9670)
-- [ ] Email encryption (PGP/GPG)
-
-### Performance Optimizations
-
-- [ ] Email content caching
-- [ ] Bundle size optimization
-- [ ] Service worker for offline support
-- [ ] Lazy loading for attachments
-
-### Testing (Remaining)
-
-- [ ] E2E tests with real JMAP server
-- [ ] Accessibility testing
-- [ ] Performance testing
-
-### Deployment
-
-- [ ] Production build optimizations
-- [ ] Monitoring and logging
-
-### Security Enhancements
-
-- [ ] Rate limiting
-
-## Known Issues
-
-- [ ] Next.js workspace root warning (cosmetic)
-
-## Contributing
-
-Want to help implement a feature? Check out our [CONTRIBUTING.md](CONTRIBUTING.md) guide!

VERSION

@@ -1 +1 @@
-1.3.0
+1.4.4

app/[locale]/auth/callback/page.tsx

@@ -53,6 +53,7 @@ function OAuthCallbackInner() {
           sessionStorage.removeItem("oauth_state");
           sessionStorage.removeItem("oauth_code_verifier");
           sessionStorage.removeItem("oauth_server_url");
+          sessionStorage.removeItem("oauth_add_account_mode");
           let redirectTo = `/${params.locale}`;
           try {
             const saved = sessionStorage.getItem('redirect_after_login');

app/[locale]/calendar/page.tsx

@@ -10,6 +10,7 @@ import {
   format, parseISO,
 } from "date-fns";
 import { useCalendarStore } from "@/stores/calendar-store";
+import { isCalendarViewMode } from "@/stores/calendar-store";
 import { useAuthStore } from "@/stores/auth-store";
 import { useEmailStore } from "@/stores/email-store";
 import { useSettingsStore } from "@/stores/settings-store";
@@ -30,6 +31,9 @@ import { ICalImportModal } from "@/components/calendar/ical-import-modal";
 import { ICalSubscriptionModal } from "@/components/calendar/ical-subscription-modal";
 import { RecurrenceScopeDialog, type RecurrenceEditScope } from "@/components/calendar/recurrence-scope-dialog";
 import { NavigationRail } from "@/components/layout/navigation-rail";
+import { SidebarAppsModal } from "@/components/layout/sidebar-apps-modal";
+import { InlineAppView } from "@/components/layout/inline-app-view";
+import { useSidebarApps } from "@/hooks/use-sidebar-apps";
 import { ResizeHandle } from "@/components/layout/resize-handle";
 import { cn } from "@/lib/utils";
 import type { CalendarEvent, CalendarParticipant } from "@/lib/jmap/types";
@@ -48,6 +52,7 @@ export default function CalendarPage() {
   const router = useRouter();
   const t = useTranslations("calendar");
   const isMobile = useIsMobile();
+  const { showAppsModal, inlineApp, loadedApps, handleManageApps, handleInlineApp, closeInlineApp, closeAppsModal } = useSidebarApps();
   const { client, isAuthenticated, logout, checkAuth, isLoading: authLoading } = useAuthStore();
   const [initialCheckDone, setInitialCheckDone] = useState(() => useAuthStore.getState().isAuthenticated && !!useAuthStore.getState().client);
   const { quota, isPushConnected } = useEmailStore();
@@ -60,6 +65,7 @@ export default function CalendarPage() {
   } = useCalendarStore();
   const { firstDayOfWeek, timeFormat } = useSettingsStore();
   const { identities } = useIdentityStore();
+  const normalizedViewMode = isCalendarViewMode(viewMode) ? viewMode : "month";
 
   const currentUserEmails = useMemo(() =>
     identities.map(id => id.email).filter(Boolean),
@@ -129,7 +135,7 @@ export default function CalendarPage() {
 
   const dateRange = useMemo(() => {
     const d = selectedDate;
-    switch (viewMode) {
+    switch (normalizedViewMode) {
       case "month": {
         const ms = startOfMonth(d);
         const me = endOfMonth(d);
@@ -156,17 +162,17 @@ export default function CalendarPage() {
           end: format(addDays(d, 30), "yyyy-MM-dd'T'23:59:59"),
         };
     }
-  }, [selectedDate, viewMode, firstDayOfWeek]);
+  }, [selectedDate, normalizedViewMode, firstDayOfWeek]);
 
   useEffect(() => {
-    if (client && calendars.length > 0) {
+    if (client && calendars.length > 0 && dateRange) {
       fetchEvents(client, dateRange.start, dateRange.end);
     }
   }, [client, calendars.length, dateRange, fetchEvents]);
 
   const navigatePrev = useCallback(() => {
     let next: Date;
-    switch (viewMode) {
+    switch (normalizedViewMode) {
       case "month": next = subMonths(selectedDate, 1); break;
       case "week": next = subWeeks(selectedDate, 1); break;
       case "day": next = subDays(selectedDate, 1); break;
@@ -174,11 +180,11 @@ export default function CalendarPage() {
     }
     setSelectedDate(next);
     setMiniMonth(next);
-  }, [viewMode, selectedDate, setSelectedDate]);
+  }, [normalizedViewMode, selectedDate, setSelectedDate]);
 
   const navigateNext = useCallback(() => {
     let next: Date;
-    switch (viewMode) {
+    switch (normalizedViewMode) {
       case "month": next = addMonths(selectedDate, 1); break;
       case "week": next = addWeeks(selectedDate, 1); break;
       case "day": next = addDays(selectedDate, 1); break;
@@ -186,7 +192,7 @@ export default function CalendarPage() {
     }
     setSelectedDate(next);
     setMiniMonth(next);
-  }, [viewMode, selectedDate, setSelectedDate]);
+  }, [normalizedViewMode, selectedDate, setSelectedDate]);
 
   const goToToday = useCallback(() => {
     setSelectedDate(new Date());
@@ -218,10 +224,10 @@ export default function CalendarPage() {
     setSelectedDate(date);
     setMiniMonth(date);
     // On mobile month view, tapping a date switches to day view
-    if (isMobile && viewMode === "month") {
+    if (isMobile && normalizedViewMode === "month") {
       setViewMode("day");
     }
-  }, [setSelectedDate, isMobile, viewMode, setViewMode]);
+  }, [setSelectedDate, isMobile, normalizedViewMode, setViewMode]);
 
   const handleMiniMonthChange = useCallback((date: Date) => {
     setMiniMonth(date);
@@ -230,10 +236,12 @@ export default function CalendarPage() {
 
   const openCreateModal = useCallback((date?: Date, endDate?: Date) => {
     setEditEvent(null);
-    setDefaultModalDate(date || selectedDate);
+    const d = date || selectedDate;
+    setDefaultModalDate(d);
     setDefaultModalEndDate(endDate);
+    setSelectedDate(d);
     setShowEventModal(true);
-  }, [selectedDate]);
+  }, [selectedDate, setSelectedDate]);
 
   const openEditModal = useCallback((event: CalendarEvent) => {
     setEditEvent(event);
@@ -603,6 +611,7 @@ export default function CalendarPage() {
 
   const visibleEvents = useMemo(() =>
     events.filter((e) => {
+      if (!e.calendarIds) return false;
       const calIds = Object.keys(e.calendarIds);
       return calIds.some((id) => selectedCalendarIds.includes(id));
     }),
@@ -621,7 +630,7 @@ export default function CalendarPage() {
     }
 
     const viewContent = (() => {
-      switch (viewMode) {
+      switch (normalizedViewMode) {
         case "month":
           return (
             <CalendarMonthView
@@ -632,6 +641,7 @@ export default function CalendarPage() {
               onSelectEvent={handleSelectEvent}
               onHoverEvent={handleHoverEvent}
               onHoverLeave={handleHoverLeave}
+              onCreateAtTime={openCreateModal}
               firstDayOfWeek={firstDayOfWeek}
               isMobile={isMobile}
             />
@@ -684,7 +694,7 @@ export default function CalendarPage() {
     return (
       <div className="relative flex-1 flex flex-col overflow-hidden">
         {viewContent}
-        {isLoadingEvents && calendars.length > 0 && (
+        {isLoadingEvents && calendars.length > 0 && events.length === 0 && (
           <div className="absolute inset-0 bg-background/50 flex items-center justify-center pointer-events-none">
             <div className="h-5 w-5 border-2 border-primary border-t-transparent rounded-full animate-spin" />
           </div>
@@ -702,13 +712,21 @@ export default function CalendarPage() {
             collapsed
             quota={quota}
             isPushConnected={isPushConnected}
-            onLogout={() => { logout(); router.push('/login'); }}
+            onLogout={() => { logout(); if (!useAuthStore.getState().isAuthenticated) router.push('/login'); }}
+            onManageApps={handleManageApps}
+            onInlineApp={handleInlineApp}
+            onCloseInlineApp={closeInlineApp}
+            activeAppId={inlineApp?.id ?? null}
           />
         </div>
       )}
 
+      {inlineApp && (
+        <InlineAppView apps={loadedApps} activeAppId={inlineApp!.id} onClose={closeInlineApp} className="flex-1" />
+      )}
+
       {/* Sidebar - full height */}
-      {!isMobile && (
+      {!isMobile && !inlineApp && (
         <>
           <div
             className={cn(
@@ -748,10 +766,11 @@ export default function CalendarPage() {
         </>
       )}
 
+      {!inlineApp && (
       <div className="flex flex-col flex-1 min-w-0">
         <CalendarToolbar
           selectedDate={selectedDate}
-          viewMode={viewMode}
+          viewMode={normalizedViewMode}
           onPrev={navigatePrev}
           onNext={navigateNext}
           onToday={goToToday}
@@ -776,6 +795,7 @@ export default function CalendarPage() {
           {!isMobile && showEventModal && (
             <div className="w-[400px] border-l border-border flex-shrink-0 overflow-hidden">
               <EventModal
+                key={editEvent?.id ?? 'new'}
                 event={editEvent}
                 calendars={calendars}
                 defaultDate={defaultModalDate}
@@ -802,12 +822,19 @@ export default function CalendarPage() {
             </Button>
           )}
         </div>
-
-        {/* Mobile Bottom Navigation */}
-        {isMobile && (
-          <NavigationRail orientation="horizontal" />
-        )}
       </div>
+      )}
+
+      {/* Mobile Bottom Navigation */}
+      {isMobile && (
+        <NavigationRail
+          orientation="horizontal"
+          onManageApps={handleManageApps}
+          onInlineApp={handleInlineApp}
+          onCloseInlineApp={closeInlineApp}
+          activeAppId={inlineApp?.id ?? null}
+        />
+      )}
 
       {detailEvent && detailAnchorRect && (
         <EventDetailPopover
@@ -830,6 +857,7 @@ export default function CalendarPage() {
 
       {showEventModal && isMobile && (
         <EventModal
+          key={editEvent?.id ?? 'new'}
           event={editEvent}
           calendars={calendars}
           defaultDate={defaultModalDate}
@@ -859,6 +887,7 @@ export default function CalendarPage() {
         />
       )}
 
+      <SidebarAppsModal isOpen={showAppsModal} onClose={closeAppsModal} />
       <RecurrenceScopeDialog
         isOpen={!!pendingScopeAction}
         actionType={pendingScopeAction?.type || "edit"}

app/[locale]/contacts/page.tsx

@@ -13,6 +13,7 @@ import { ContactForm } from "@/components/contacts/contact-form";
 import { ContactGroupForm } from "@/components/contacts/contact-group-form";
 import { ContactGroupDetail } from "@/components/contacts/contact-group-detail";
 import { ContactsSidebar, type ContactCategory } from "@/components/contacts/contacts-sidebar";
+import { ContactImportDialog } from "@/components/contacts/contact-import-dialog";
 import { exportContacts } from "@/components/contacts/contact-export";
 import { useContactStore, getContactDisplayName } from "@/stores/contact-store";
 import { useAuthStore } from "@/stores/auth-store";
@@ -20,9 +21,12 @@ import { useEmailStore } from "@/stores/email-store";
 import { toast } from "@/stores/toast-store";
 import { cn } from "@/lib/utils";
 import { NavigationRail } from "@/components/layout/navigation-rail";
+import { SidebarAppsModal } from "@/components/layout/sidebar-apps-modal";
+import { InlineAppView } from "@/components/layout/inline-app-view";
+import { useSidebarApps } from "@/hooks/use-sidebar-apps";
 import { ResizeHandle } from "@/components/layout/resize-handle";
 import { useIsMobile } from "@/hooks/use-media-query";
-import type { ContactCard } from "@/lib/jmap/types";
+import type { ContactCard, AddressBook } from "@/lib/jmap/types";
 
 type View =
   | "list"
@@ -38,10 +42,12 @@ export default function ContactsPage() {
   const router = useRouter();
   const t = useTranslations("contacts");
   const { client, isAuthenticated, logout, checkAuth, isLoading: authLoading } = useAuthStore();
+  const { showAppsModal, inlineApp, loadedApps, handleManageApps, handleInlineApp, closeInlineApp, closeAppsModal } = useSidebarApps();
   const [initialCheckDone, setInitialCheckDone] = useState(() => useAuthStore.getState().isAuthenticated && !!useAuthStore.getState().client);
   const { quota, isPushConnected } = useEmailStore();
   const {
     contacts,
+    addressBooks,
     selectedContactId,
     searchQuery,
     supportsSync,
@@ -67,10 +73,13 @@ export default function ContactsPage() {
     clearSelection,
     bulkDeleteContacts,
     bulkAddToGroup,
+    moveContactToAddressBook,
+    importContacts,
   } = useContactStore();
 
   const [view, setView] = useState<View>("list");
   const [activeCategory, setActiveCategory] = useState<ContactCategory>("all");
+  const [showImportDialog, setShowImportDialog] = useState(false);
   const [selectedGroupId, setSelectedGroupId] = useState<string | null>(null);
   const hasFetched = useRef(false);
   const { dialogProps: confirmDialogProps, confirm: confirmDialog } = useConfirmDialog();
@@ -78,10 +87,10 @@ export default function ContactsPage() {
 
   // Panel resize state - sidebar (categories)
   const [sidebarWidth, setSidebarWidth] = useState(() => {
-    try { const v = localStorage.getItem("contacts-sidebar-width"); return v ? Number(v) : 180; } catch { return 180; }
+    try { const v = localStorage.getItem("contacts-sidebar-width"); return v ? Number(v) : 256; } catch { return 256; }
   });
   const [isSidebarResizing, setIsSidebarResizing] = useState(false);
-  const sidebarDragStartWidth = useRef(180);
+  const sidebarDragStartWidth = useRef(256);
 
   // Panel resize state - contact list
   const [listWidth, setListWidth] = useState(() => {
@@ -120,6 +129,16 @@ export default function ContactsPage() {
   // Contacts to display based on active category
   const displayedContacts = useMemo(() => {
     if (activeCategory === "all") return individuals;
+    if ("addressBookId" in activeCategory) {
+      const bookId = activeCategory.addressBookId;
+      return individuals.filter(c => {
+        if (!c.addressBookIds) return false;
+        return c.addressBookIds[bookId] === true;
+      });
+    }
+    if ("keyword" in activeCategory) {
+      return individuals.filter(c => c.keywords?.[activeCategory.keyword]);
+    }
     // Show members of the selected group
     return getGroupMembers(activeCategory.groupId);
   }, [activeCategory, individuals, getGroupMembers]);
@@ -127,20 +146,49 @@ export default function ContactsPage() {
   // Label for the current category
   const categoryLabel = useMemo(() => {
     if (activeCategory === "all") return t("tabs.all");
+    if ("addressBookId" in activeCategory) {
+      const book = addressBooks.find(b => b.id === activeCategory.addressBookId);
+      return book?.name || t("tabs.all");
+    }
+    if ("keyword" in activeCategory) {
+      return activeCategory.keyword;
+    }
     const group = contacts.find(c => c.id === activeCategory.groupId);
     return group ? getContactDisplayName(group) : t("tabs.all");
-  }, [activeCategory, contacts, t]);
+  }, [activeCategory, contacts, addressBooks, t]);
 
   const handleSelectCategory = useCallback((category: ContactCategory) => {
     setActiveCategory(category);
     clearSelection();
-    if (typeof category === "object") {
+    if (typeof category === "object" && "groupId" in category) {
       setSelectedGroupId(category.groupId);
+      setView("group-detail");
     } else {
       setSelectedGroupId(null);
     }
   }, [clearSelection]);
 
+  const handleDropContacts = useCallback(async (contactIds: string[], addressBook: AddressBook) => {
+    if (!client) return;
+    try {
+      await moveContactToAddressBook(client, contactIds, addressBook);
+      const msg = contactIds.length === 1
+        ? t("address_books.moved", { name: addressBook.name })
+        : t("address_books.moved_plural", { count: contactIds.length, name: addressBook.name });
+      toast.success(msg);
+    } catch (error) {
+      console.error('Failed to move contacts:', error);
+      toast.error(t("address_books.move_failed"));
+    }
+  }, [client, moveContactToAddressBook, t]);
+
+  const handleImportContacts = useCallback(async (importedContacts: ContactCard[]) => {
+    return importContacts(
+      supportsSync && client ? client : null,
+      importedContacts
+    );
+  }, [supportsSync, client, importContacts]);
+
   const handleSelectContact = (id: string) => {
     setSelectedContact(id);
     clearSelection();
@@ -235,6 +283,35 @@ export default function ContactsPage() {
     setView("group-edit");
   };
 
+  const handleEditGroupFromSidebar = useCallback((groupId: string) => {
+    setSelectedGroupId(groupId);
+    setActiveCategory({ groupId });
+    setView("group-edit");
+  }, []);
+
+  const handleDeleteGroupFromSidebar = useCallback(async (groupId: string) => {
+    const confirmed = await confirmDialog({
+      title: t("groups.delete_confirm_title"),
+      message: t("groups.delete_confirm"),
+      confirmText: t("form.delete"),
+      variant: "destructive",
+    });
+    if (!confirmed) return;
+
+    try {
+      await deleteGroup(supportsSync && client ? client : null, groupId);
+      toast.success(t("toast.deleted"));
+      if (selectedGroupId === groupId) {
+        setSelectedGroupId(null);
+        setActiveCategory("all");
+        setView("list");
+      }
+    } catch (error) {
+      console.error('Failed to delete group:', error);
+      toast.error(t("toast.error_delete"));
+    }
+  }, [confirmDialog, deleteGroup, supportsSync, client, selectedGroupId, t]);
+
   const handleDeleteGroup = async () => {
     if (!selectedGroup) return;
 
@@ -353,13 +430,14 @@ export default function ContactsPage() {
   const renderRightPanel = () => {
     switch (view) {
       case "create":
-        return <ContactForm onSave={handleSaveNew} onCancel={handleCancel} />;
+        return <ContactForm addressBooks={addressBooks} onSave={handleSaveNew} onCancel={handleCancel} />;
 
       case "edit":
         if (!selectedContact) return null;
         return (
           <ContactForm
             contact={selectedContact}
+            addressBooks={addressBooks}
             onSave={handleSaveEdit}
             onCancel={handleCancel}
           />
@@ -377,7 +455,6 @@ export default function ContactsPage() {
             isMobile={isMobile}
             onSelectMember={(id) => {
               setSelectedContact(id);
-              setActiveCategory("all");
               setView("detail");
             }}
           />
@@ -475,13 +552,20 @@ export default function ContactsPage() {
             collapsed
             quota={quota}
             isPushConnected={isPushConnected}
-            onLogout={() => { logout(); router.push('/login'); }}
+            onLogout={() => { logout(); if (!useAuthStore.getState().isAuthenticated) router.push('/login'); }}
+            onManageApps={handleManageApps}
+            onInlineApp={handleInlineApp}
+            onCloseInlineApp={closeInlineApp}
+            activeAppId={inlineApp?.id ?? null}
           />
         </div>
       )}
 
       <div className="flex flex-col flex-1 min-w-0">
-        <div className="flex flex-1 min-h-0">
+        {inlineApp && (
+          <InlineAppView apps={loadedApps} activeAppId={inlineApp!.id} onClose={closeInlineApp} />
+        )}
+        <div className={cn("flex flex-1 min-h-0", inlineApp && "hidden")}>
           {showListPanel && (
             <>
               {/* Panel 1: Categories sidebar */}
@@ -497,20 +581,25 @@ export default function ContactsPage() {
                     <ContactsSidebar
                       groups={groups}
                       individuals={individuals}
+                      addressBooks={addressBooks}
                       activeCategory={activeCategory}
                       onSelectCategory={handleSelectCategory}
                       onCreateGroup={handleCreateGroup}
                       onCreateContact={handleCreateNew}
+                      onImport={() => setShowImportDialog(true)}
+                      onEditGroup={handleEditGroupFromSidebar}
+                      onDeleteGroup={handleDeleteGroupFromSidebar}
+                      onDropContacts={handleDropContacts}
                     />
                   </div>
                   <ResizeHandle
                     onResizeStart={() => { sidebarDragStartWidth.current = sidebarWidth; setIsSidebarResizing(true); }}
-                    onResize={(delta) => setSidebarWidth(Math.max(140, Math.min(300, sidebarDragStartWidth.current + delta)))}
+                    onResize={(delta) => setSidebarWidth(Math.max(180, Math.min(400, sidebarDragStartWidth.current + delta)))}
                     onResizeEnd={() => {
                       setIsSidebarResizing(false);
                       localStorage.setItem("contacts-sidebar-width", String(sidebarWidth));
                     }}
-                    onDoubleClick={() => { setSidebarWidth(180); localStorage.setItem("contacts-sidebar-width", "180"); }}
+                    onDoubleClick={() => { setSidebarWidth(256); localStorage.setItem("contacts-sidebar-width", "256"); }}
                   />
                 </>
               )}
@@ -582,11 +671,29 @@ export default function ContactsPage() {
         </div>
 
         {isMobile && (
-          <NavigationRail orientation="horizontal" />
+          <NavigationRail
+            orientation="horizontal"
+            onManageApps={handleManageApps}
+            onInlineApp={handleInlineApp}
+            onCloseInlineApp={closeInlineApp}
+            activeAppId={inlineApp?.id ?? null}
+          />
         )}
       </div>
 
+      <SidebarAppsModal isOpen={showAppsModal} onClose={closeAppsModal} />
       <ConfirmDialog {...confirmDialogProps} />
+      {showImportDialog && (
+        <div className="fixed inset-0 bg-black/50 z-50 flex items-center justify-center p-4">
+          <div className="bg-background rounded-lg border border-border shadow-xl w-full max-w-2xl max-h-[80vh] overflow-hidden">
+            <ContactImportDialog
+              existingContacts={contacts}
+              onImport={handleImportContacts}
+              onClose={() => setShowImportDialog(false)}
+            />
+          </div>
+        </div>
+      )}
     </div>
   );
 }

app/[locale]/files/page.tsx

@@ -13,6 +13,9 @@ import { useFileStore } from "@/stores/file-store";
 import { toast } from "@/stores/toast-store";
 import { cn } from "@/lib/utils";
 import { NavigationRail } from "@/components/layout/navigation-rail";
+import { SidebarAppsModal } from "@/components/layout/sidebar-apps-modal";
+import { InlineAppView } from "@/components/layout/inline-app-view";
+import { useSidebarApps } from "@/hooks/use-sidebar-apps";
 import { useIsMobile } from "@/hooks/use-media-query";
 import { FileBrowser } from "@/components/files/file-browser";
 import { ImagePreviewModal } from "@/components/files/image-preview-modal";
@@ -24,6 +27,7 @@ export default function FilesPage() {
   const router = useRouter();
   const t = useTranslations("files");
   const { isAuthenticated, logout, checkAuth, isLoading: authLoading, client } = useAuthStore();
+  const { showAppsModal, inlineApp, loadedApps, handleManageApps, handleInlineApp, closeInlineApp, closeAppsModal } = useSidebarApps();
   const [initialCheckDone, setInitialCheckDone] = useState(() => useAuthStore.getState().isAuthenticated && !!useAuthStore.getState().client);
   const { quota, isPushConnected } = useEmailStore();
   const {
@@ -353,13 +357,20 @@ export default function FilesPage() {
             collapsed
             quota={quota}
             isPushConnected={isPushConnected}
-            onLogout={() => { logout(); router.push('/login'); }}
+            onLogout={() => { logout(); if (!useAuthStore.getState().isAuthenticated) router.push('/login'); }}
+            onManageApps={handleManageApps}
+            onInlineApp={handleInlineApp}
+            onCloseInlineApp={closeInlineApp}
+            activeAppId={inlineApp?.id ?? null}
           />
         </div>
       )}
 
       <div className="flex flex-col flex-1 min-w-0">
-        <div className="flex flex-1 min-h-0">
+        {inlineApp && (
+          <InlineAppView apps={loadedApps} activeAppId={inlineApp!.id} onClose={closeInlineApp} />
+        )}
+        <div className={cn("flex flex-1 min-h-0", inlineApp && "hidden")}>
           <div className="flex-1 min-w-0 flex flex-col">
             {folderLayout !== "sidebar" && (
               <div className={cn("p-4 border-b border-border", isMobile && "px-3 py-3")}>
@@ -433,7 +444,13 @@ export default function FilesPage() {
         </div>
 
         {isMobile && (
-          <NavigationRail orientation="horizontal" />
+          <NavigationRail
+            orientation="horizontal"
+            onManageApps={handleManageApps}
+            onInlineApp={handleInlineApp}
+            onCloseInlineApp={closeInlineApp}
+            activeAppId={inlineApp?.id ?? null}
+          />
         )}
       </div>
 
@@ -457,6 +474,7 @@ export default function FilesPage() {
         />
       )}
 
+      <SidebarAppsModal isOpen={showAppsModal} onClose={closeAppsModal} />
       <ConfirmDialog {...confirmDialogProps} />
     </div>
   );

app/[locale]/login/page.tsx

@@ -2,7 +2,7 @@
 
 import { useState, useEffect, useRef, useCallback } from "react";
 import { useRouter } from "@/i18n/navigation";
-import { useParams } from "next/navigation";
+import { useParams, useSearchParams } from "next/navigation";
 import { useTranslations } from "next-intl";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
@@ -16,7 +16,7 @@ import { discoverOAuth, type OAuthMetadata } from "@/lib/oauth/discovery";
 import { generateCodeVerifier, generateCodeChallenge, generateState } from "@/lib/oauth/pkce";
 import { OAUTH_SCOPES } from "@/lib/oauth/tokens";
 
-const APP_VERSION = "1.2.4";
+const APP_VERSION = "1.4.3";
 
 const THEME_OPTIONS = [
   { value: "light" as const, icon: Sun, label: "Light" },
@@ -28,6 +28,8 @@ export default function LoginPage() {
   const router = useRouter();
   const t = useTranslations("login");
   const params = useParams();
+  const searchParams = useSearchParams();
+  const isAddAccountMode = searchParams.get("mode") === "add-account";
   const { login, isLoading, error, clearError, isAuthenticated } = useAuthStore();
   const { theme, setTheme, initializeTheme } = useThemeStore(useShallow((s) => ({ theme: s.theme, setTheme: s.setTheme, initializeTheme: s.initializeTheme })));
   const { appName, jmapServerUrl: serverUrl, oauthEnabled, oauthOnly, oauthClientId, oauthIssuerUrl, rememberMeEnabled, devMode, loginLogoLightUrl, loginLogoDarkUrl, loginCompanyName, loginImprintUrl, loginPrivacyPolicyUrl, loginWebsiteUrl, isLoading: configLoading, error: configError } = useConfig();
@@ -102,7 +104,7 @@ export default function LoginPage() {
   }, [serverUrl]);
 
   useEffect(() => {
-    if (isAuthenticated) {
+    if (isAuthenticated && !isAddAccountMode) {
       let redirectTo = '/';
       try {
         const saved = sessionStorage.getItem('redirect_after_login');
@@ -113,7 +115,7 @@ export default function LoginPage() {
       } catch { /* ignore */ }
       router.push(redirectTo);
     }
-  }, [isAuthenticated, router]);
+  }, [isAuthenticated, router, isAddAccountMode]);
 
   useEffect(() => {
     clearError();
@@ -303,6 +305,9 @@ export default function LoginPage() {
     sessionStorage.setItem("oauth_code_verifier", verifier);
     sessionStorage.setItem("oauth_state", state);
     sessionStorage.setItem("oauth_server_url", serverUrl!);
+    if (isAddAccountMode) {
+      sessionStorage.setItem("oauth_add_account_mode", "true");
+    }
 
     const authUrl = new URL(oauthMetadata.authorization_endpoint);
     authUrl.searchParams.set("response_type", "code");
@@ -329,15 +334,7 @@ export default function LoginPage() {
 
     if (success) {
       saveUsername(formData.username);
-      let redirectTo = '/';
+      router.push('/');
-      try {
-        const saved = sessionStorage.getItem('redirect_after_login');
-        if (saved) {
-          sessionStorage.removeItem('redirect_after_login');
-          redirectTo = saved;
-        }
-      } catch { /* ignore */ }
-      router.push(redirectTo);
     }
   };
 
@@ -426,10 +423,10 @@ export default function LoginPage() {
               />
             </div>
             <h1 className="text-2xl font-semibold text-foreground tracking-tight">
-              {appName}
+              {isAddAccountMode ? t("add_account_title") : appName}
             </h1>
             <p className="text-sm text-muted-foreground mt-1.5">
-              {t("title") !== appName ? t("title") : "Sign in to your account"}
+              {isAddAccountMode ? t("add_account_subtitle") : (t("title") !== appName ? t("title") : "Sign in to your account")}
             </p>
           </div>
 
@@ -737,6 +734,19 @@ export default function LoginPage() {
                 )}
               </form>
             )}
+
+            {isAddAccountMode && (
+              <div className="mt-4">
+                <Button
+                  type="button"
+                  variant="ghost"
+                  className="w-full h-10 text-sm text-muted-foreground hover:text-foreground"
+                  onClick={() => router.push('/')}
+                >
+                  {t("cancel")}
+                </Button>
+              </div>
+            )}
           </div>
         </div>
 

app/[locale]/page.tsx

@@ -35,22 +35,29 @@ import { DragDropProvider } from "@/contexts/drag-drop-context";
 import { isFilterEmpty, activeFilterCount } from "@/lib/jmap/search-utils";
 import { WelcomeBanner } from "@/components/ui/welcome-banner";
 import { NavigationRail } from "@/components/layout/navigation-rail";
+import { SidebarAppsModal } from "@/components/layout/sidebar-apps-modal";
+import { InlineAppView } from "@/components/layout/inline-app-view";
+import { useSidebarApps } from "@/hooks/use-sidebar-apps";
 import { Input } from "@/components/ui/input";
 import { FilePreviewModal } from "@/components/files/file-preview-modal";
 import { isFilePreviewable } from "@/lib/file-preview";
+import { appendPlainTextSignature } from "@/lib/signature-utils";
 import { Search, Filter, ChevronDown, X, Paperclip, Star, Mail, MailOpen, RotateCcw, PenSquare, PenLine, CheckSquare, Square } from "lucide-react";
 import { ResizeHandle } from "@/components/layout/resize-handle";
 import { Button } from "@/components/ui/button";
+import { useConfig } from "@/hooks/use-config";
 
 export default function Home() {
   const router = useRouter();
   const t = useTranslations();
   const tCommon = useTranslations('common');
+  const { appName } = useConfig();
   const [showComposer, setShowComposer] = useState(false);
   const [composerMode, setComposerMode] = useState<'compose' | 'reply' | 'replyAll' | 'forward'>('compose');
   const [composerDraftText, setComposerDraftText] = useState("");
   const [pendingDraft, setPendingDraft] = useState<ComposerDraftData | null>(null);
   const { dialogProps: confirmDialogProps, confirm: confirmDialog } = useConfirmDialog();
+  const { showAppsModal, inlineApp, loadedApps, handleManageApps, handleInlineApp, closeInlineApp, closeAppsModal } = useSidebarApps();
   const [initialCheckDone, setInitialCheckDone] = useState(() => useAuthStore.getState().isAuthenticated && !!useAuthStore.getState().client);
   const [showShortcutsModal, setShowShortcutsModal] = useState(false);
   const [showAdvancedFields, setShowAdvancedFields] = useState(false);
@@ -224,7 +231,7 @@ export default function Home() {
 
   // Update page title based on context
   useEffect(() => {
-    let title = tCommon('app_title');
+    let title = appName;
 
     if (showComposer) {
       // Composing email
@@ -234,11 +241,11 @@ export default function Home() {
         replyAll: t('email_composer.reply_all'),
         forward: t('email_composer.forward'),
       }[composerMode] || t('email_composer.new_message');
-      title = `${modeText} - ${tCommon('app_title')}`;
+      title = `${modeText} - ${appName}`;
     } else if (selectedEmail) {
       // Reading email
       const subject = selectedEmail.subject || t('email_viewer.no_subject');
-      title = `${subject} - ${tCommon('app_title')}`;
+      title = `${subject} - ${appName}`;
     } else if (selectedMailbox && mailboxes.length > 0) {
       // Mailbox view
       const mailbox = mailboxes.find(mb => mb.id === selectedMailbox);
@@ -246,13 +253,13 @@ export default function Home() {
         const mailboxName = mailbox.name;
         const unreadCount = mailbox.unreadEmails || 0;
         title = unreadCount > 0
-          ? `${mailboxName} (${unreadCount}) - ${tCommon('app_title')}`
+          ? `${mailboxName} (${unreadCount}) - ${appName}`
-          : `${mailboxName} - ${tCommon('app_title')}`;
+          : `${mailboxName} - ${appName}`;
       }
     }
 
     document.title = title;
-  }, [showComposer, composerMode, selectedEmail, selectedMailbox, mailboxes, t, tCommon]);
+  }, [showComposer, composerMode, selectedEmail, selectedMailbox, mailboxes, t, appName]);
 
   // Check auth on mount
   useEffect(() => {
@@ -431,11 +438,12 @@ export default function Home() {
     fromEmail?: string;
     fromName?: string;
     identityId?: string;
+    attachments?: Array<{ blobId: string; name: string; type: string; size: number }>;
   }) => {
     if (!client) return;
 
     try {
-      await sendEmail(client, data.to, data.subject, data.body, data.cc, data.bcc, data.identityId, data.fromEmail, data.draftId, data.fromName, data.htmlBody);
+      await sendEmail(client, data.to, data.subject, data.body, data.cc, data.bcc, data.identityId, data.fromEmail, data.draftId, data.fromName, data.htmlBody, data.attachments);
       setShowComposer(false);
 
       // Refresh the current mailbox to update the UI
@@ -462,6 +470,33 @@ export default function Home() {
     if (isMobile) setActiveView('viewer');
   };
 
+  const handleEditDraft = (email?: Email) => {
+    const draft = email || selectedEmail;
+    if (!draft) return;
+    const bodyText = draft.bodyValues
+      ? Object.values(draft.bodyValues).map(v => v.value).join('\n')
+      : '';
+    const htmlBody = draft.htmlBody?.[0]?.partId && draft.bodyValues?.[draft.htmlBody[0].partId]
+      ? draft.bodyValues[draft.htmlBody[0].partId].value
+      : undefined;
+    setPendingDraft({
+      to: draft.to?.map(a => a.email).filter(Boolean).join(', ') || '',
+      cc: draft.cc?.map(a => a.email).filter(Boolean).join(', ') || '',
+      bcc: draft.bcc?.map(a => a.email).filter(Boolean).join(', ') || '',
+      subject: draft.subject || '',
+      body: htmlBody || bodyText,
+      showCc: (draft.cc?.length || 0) > 0,
+      showBcc: (draft.bcc?.length || 0) > 0,
+      selectedIdentityId: null,
+      subAddressTag: '',
+      mode: 'compose',
+      draftId: draft.id,
+    });
+    setComposerMode('compose');
+    setShowComposer(true);
+    if (isMobile) setActiveView('viewer');
+  };
+
   const handleReplyAll = () => {
     setComposerMode('replyAll');
     setShowComposer(true);
@@ -516,12 +551,46 @@ export default function Home() {
 
     // Find archive mailbox
     const archiveMailbox = mailboxes.find(m => m.role === "archive" || m.name.toLowerCase() === "archive");
-    if (archiveMailbox) {
+    if (!archiveMailbox) return;
-      try {
+
+    const { archiveMode } = useSettingsStore.getState();
+
+    try {
+      if (archiveMode === 'single') {
         await moveToMailbox(client, selectedEmail.id, archiveMailbox.id);
-      } catch (error) {
+      } else {
-        console.error("Failed to archive email:", error);
+        // Determine year/month from the email's received date
+        const emailDate = new Date(selectedEmail.receivedAt);
+        const year = emailDate.getFullYear().toString();
+        const month = (emailDate.getMonth() + 1).toString().padStart(2, '0');
+        const archiveId = archiveMailbox.originalId || archiveMailbox.id;
+
+        // Find or create year subfolder under archive
+        let yearMailbox = mailboxes.find(
+          m => m.name === year && m.parentId === archiveId
+        );
+        if (!yearMailbox) {
+          yearMailbox = await client.createMailbox(year, archiveId);
+          await fetchMailboxes(client);
+        }
+
+        if (archiveMode === 'year') {
+          await moveToMailbox(client, selectedEmail.id, yearMailbox.id);
+        } else {
+          // archiveMode === 'month' — find or create month subfolder under year
+          const yearId = yearMailbox.originalId || yearMailbox.id;
+          let monthMailbox = mailboxes.find(
+            m => m.name === month && m.parentId === yearId
+          );
+          if (!monthMailbox) {
+            monthMailbox = await client.createMailbox(month, yearId);
+            await fetchMailboxes(client);
+          }
+          await moveToMailbox(client, selectedEmail.id, monthMailbox.id);
+        }
       }
+    } catch (error) {
+      console.error("Failed to archive email:", error);
     }
   };
 
@@ -701,7 +770,9 @@ export default function Home() {
 
   const handleLogout = () => {
     logout();
-    router.push('/login');
+    if (!useAuthStore.getState().isAuthenticated) {
+      router.push('/login');
+    }
   };
 
   const handleSearch = async (query: string) => {
@@ -792,10 +863,7 @@ export default function Home() {
     const primaryIdentity = identities[0];
 
     // Append signature from the primary identity
-    let finalBody = body;
+    const finalBody = appendPlainTextSignature(body, primaryIdentity);
-    if (primaryIdentity?.textSignature) {
-      finalBody = body + '\n\n-- \n' + primaryIdentity.textSignature;
-    }
 
     // Send reply with just the body text
     await sendEmail(
@@ -952,6 +1020,10 @@ export default function Home() {
     </button>
   );
 
+  if (!isAuthenticated) {
+    return null;
+  }
+
   return (
     <DragDropProvider>
       <div className="flex flex-col h-dvh bg-background overflow-hidden">
@@ -971,12 +1043,20 @@ export default function Home() {
               isPushConnected={isPushConnected}
               onLogout={handleLogout}
               onShowShortcuts={() => setShowShortcutsModal(true)}
+              onManageApps={handleManageApps}
+              onInlineApp={handleInlineApp}
+              onCloseInlineApp={closeInlineApp}
+              activeAppId={inlineApp?.id ?? null}
             />
           </div>
         )}
 
+        {inlineApp && (
+          <InlineAppView apps={loadedApps} activeAppId={inlineApp!.id} onClose={closeInlineApp} className="flex-1" />
+        )}
+
         {/* Mobile/Tablet Sidebar Overlay Backdrop */}
-        {(isMobile || isTablet) && sidebarOpen && (
+        {(isMobile || isTablet) && sidebarOpen && !inlineApp && (
           <div
             className="fixed inset-0 bg-black/50 z-40 lg:hidden"
             onClick={() => setSidebarOpen(false)}
@@ -993,7 +1073,8 @@ export default function Home() {
             "max-lg:transform max-lg:transition-transform max-lg:duration-300 max-lg:ease-in-out",
             !sidebarOpen && "max-lg:-translate-x-full",
             // Desktop: normal flow
-            "lg:relative lg:translate-x-0"
+            "lg:relative lg:translate-x-0",
+            inlineApp && "hidden"
           )}
           style={!isMobile && !isTablet ? { width: sidebarCollapsed ? 64 : sidebarWidth } : undefined}
         >
@@ -1019,7 +1100,7 @@ export default function Home() {
         </div>
 
         {/* Sidebar resize handle (desktop only, hidden when collapsed) */}
-        {!isMobile && !isTablet && !sidebarCollapsed && (
+        {!isMobile && !isTablet && !sidebarCollapsed && !inlineApp && (
           <ResizeHandle
             onResizeStart={() => { dragStartWidth.current = sidebarWidth; setIsResizing(true); }}
             onResize={(delta) => setSidebarWidth(dragStartWidth.current + delta)}
@@ -1029,7 +1110,7 @@ export default function Home() {
         )}
 
         {/* Main Content Area */}
-        <div className="flex flex-col flex-1 min-w-0 h-full">
+        <div className={cn("flex flex-col flex-1 min-w-0 h-full", inlineApp && "hidden")}>
           <div className="flex flex-1 min-h-0">
           {/* Email List - full width on mobile, fixed width on tablet/desktop */}
           <div
@@ -1321,6 +1402,9 @@ export default function Home() {
                   selectEmail(email);
                   await handleUndoSpam();
                 }}
+                onEditDraft={(email) => {
+                  handleEditDraft(email);
+                }}
                 className="flex-1 min-h-0"
               />
             </ErrorBoundary>
@@ -1494,6 +1578,7 @@ export default function Home() {
                     onNavigateNext={handleNavigateNext}
                     onNavigatePrev={handleNavigatePrev}
                     onShowShortcuts={() => setShowShortcutsModal(true)}
+                    onEditDraft={handleEditDraft}
                     currentUserEmail={client?.["username"]}
                     currentUserName={client?.["username"]?.split("@")[0]}
                     currentMailboxRole={mailboxes.find(m => m.id === selectedMailbox)?.role}
@@ -1516,7 +1601,13 @@ export default function Home() {
 
           {/* Bottom Navigation - mobile and tablet */}
           {(isMobile || isTablet) && activeView !== "viewer" && (
-            <NavigationRail orientation="horizontal" />
+            <NavigationRail
+              orientation="horizontal"
+              onManageApps={handleManageApps}
+              onInlineApp={handleInlineApp}
+              onCloseInlineApp={closeInlineApp}
+              activeAppId={inlineApp?.id ?? null}
+            />
           )}
         </div>
         </div>
@@ -1539,6 +1630,7 @@ export default function Home() {
         {/* Screen reader live region for dynamic status announcements */}
         <div className="sr-only" aria-live="polite" aria-atomic="true" id="sr-status" />
 
+        <SidebarAppsModal isOpen={showAppsModal} onClose={closeAppsModal} />
         <ConfirmDialog {...confirmDialogProps} />
       </div>
     </DragDropProvider>

app/[locale]/settings/page.tsx

@@ -22,6 +22,8 @@ import {
   HardDrive,
   Wrench,
   BookUser,
+  KeyRound,
+  PanelLeftClose,
   type LucideIcon,
 } from 'lucide-react';
 import { Button } from '@/components/ui/button';
@@ -40,15 +42,20 @@ import { KeywordSettings } from '@/components/settings/keyword-settings';
 import { AccountSecuritySettings } from '@/components/settings/account-security-settings';
 import { FilesSettingsComponent } from '@/components/settings/files-settings';
 import { ContactsSettings } from '@/components/settings/contacts-settings';
+import { SmimeSettings } from '@/components/settings/smime-settings';
+import { SidebarAppsSettings } from '@/components/settings/sidebar-apps-settings';
 import { useAuthStore } from '@/stores/auth-store';
 import { useEmailStore } from '@/stores/email-store';
 import { useIsDesktop } from '@/hooks/use-media-query';
 import { NavigationRail } from '@/components/layout/navigation-rail';
+import { SidebarAppsModal } from '@/components/layout/sidebar-apps-modal';
+import { InlineAppView } from '@/components/layout/inline-app-view';
+import { useSidebarApps } from '@/hooks/use-sidebar-apps';
 import { ResizeHandle } from '@/components/layout/resize-handle';
 import { useConfig } from '@/hooks/use-config';
 import { cn } from '@/lib/utils';
 
-type Tab = 'appearance' | 'email' | 'account' | 'security' | 'identities' | 'vacation' | 'calendar' | 'contacts' | 'filters' | 'templates' | 'folders' | 'keywords' | 'files' | 'advanced';
+type Tab = 'appearance' | 'email' | 'account' | 'security' | 'identities' | 'encryption' | 'vacation' | 'calendar' | 'contacts' | 'filters' | 'templates' | 'folders' | 'keywords' | 'files' | 'sidebar_apps' | 'advanced';
 type TabGroup = 'general' | 'account' | 'organization' | 'apps' | 'system';
 
 interface TabDef {
@@ -64,6 +71,7 @@ const tabIcons: Record<Tab, LucideIcon> = {
   account: User,
   security: Shield,
   identities: UserPen,
+  encryption: KeyRound,
   vacation: PalmtreeIcon,
   calendar: Calendar,
   contacts: BookUser,
@@ -72,6 +80,7 @@ const tabIcons: Record<Tab, LucideIcon> = {
   folders: FolderOpen,
   keywords: Tags,
   files: HardDrive,
+  sidebar_apps: PanelLeftClose,
   advanced: Wrench,
 };
 
@@ -82,6 +91,7 @@ export default function SettingsPage() {
   const t = useTranslations('settings');
   const tSidebar = useTranslations('sidebar');
   const { client, isAuthenticated, logout, checkAuth, isLoading: authLoading } = useAuthStore();
+  const { showAppsModal, inlineApp, loadedApps, handleManageApps, handleInlineApp, closeInlineApp, closeAppsModal } = useSidebarApps();
   const [initialCheckDone, setInitialCheckDone] = useState(() => useAuthStore.getState().isAuthenticated && !!useAuthStore.getState().client);
   const { quota, isPushConnected } = useEmailStore();
   const { stalwartFeaturesEnabled } = useConfig();
@@ -131,6 +141,7 @@ export default function SettingsPage() {
     { id: 'account', label: t('tabs.account'), icon: tabIcons.account, group: 'account' },
     ...(stalwartFeaturesEnabled ? [{ id: 'security' as Tab, label: t('tabs.security'), icon: tabIcons.security, group: 'account' as TabGroup }] : []),
     { id: 'identities', label: t('tabs.identities'), icon: tabIcons.identities, group: 'account' },
+    { id: 'encryption', label: t('tabs.encryption'), icon: tabIcons.encryption, group: 'account' },
     ...(supportsVacation ? [{ id: 'vacation' as Tab, label: t('tabs.vacation'), icon: tabIcons.vacation, group: 'account' as TabGroup }] : []),
     ...(supportsSieve ? [{ id: 'filters' as Tab, label: t('tabs.filters'), icon: tabIcons.filters, group: 'organization' as TabGroup }] : []),
     { id: 'templates', label: t('tabs.templates'), icon: tabIcons.templates, group: 'organization' },
@@ -139,6 +150,7 @@ export default function SettingsPage() {
     ...(supportsCalendar ? [{ id: 'calendar' as Tab, label: t('tabs.calendar'), icon: tabIcons.calendar, group: 'apps' as TabGroup }] : []),
     { id: 'contacts', label: t('tabs.contacts'), icon: tabIcons.contacts, group: 'apps' },
     ...(supportsFiles ? [{ id: 'files' as Tab, label: t('tabs.files'), icon: tabIcons.files, group: 'apps' as TabGroup }] : []),
+    { id: 'sidebar_apps', label: t('tabs.sidebar_apps'), icon: tabIcons.sidebar_apps, group: 'apps' },
     { id: 'advanced', label: t('tabs.advanced'), icon: tabIcons.advanced, group: 'system' },
   ];
 
@@ -168,6 +180,7 @@ export default function SettingsPage() {
       {activeTab === 'account' && <AccountSettings />}
       {activeTab === 'security' && <AccountSecuritySettings />}
       {activeTab === 'identities' && <IdentitySettings />}
+      {activeTab === 'encryption' && <SmimeSettings />}
       {activeTab === 'vacation' && <VacationSettings />}
       {activeTab === 'calendar' && <><CalendarSettings /><div className="mt-8"><CalendarManagementSettings /></div></>}
       {activeTab === 'contacts' && <ContactsSettings />}
@@ -176,6 +189,7 @@ export default function SettingsPage() {
       {activeTab === 'folders' && <FolderSettings />}
       {activeTab === 'keywords' && <KeywordSettings />}
       {activeTab === 'files' && <FilesSettingsComponent />}
+      {activeTab === 'sidebar_apps' && <SidebarAppsSettings />}
       {activeTab === 'advanced' && <AdvancedSettings />}
     </>
   );
@@ -207,7 +221,14 @@ export default function SettingsPage() {
           </div>
 
           {/* Bottom Navigation */}
-          <NavigationRail orientation="horizontal" />
+          <NavigationRail
+            orientation="horizontal"
+            onManageApps={handleManageApps}
+            onInlineApp={handleInlineApp}
+            onCloseInlineApp={closeInlineApp}
+            activeAppId={inlineApp?.id ?? null}
+          />
+          <SidebarAppsModal isOpen={showAppsModal} onClose={closeAppsModal} />
         </div>
       );
     }
@@ -265,7 +286,7 @@ export default function SettingsPage() {
           {/* Logout */}
           <div className="border-t border-border px-5 py-3">
             <button
-              onClick={() => { logout(); router.push('/login'); }}
+              onClick={() => { logout(); if (!useAuthStore.getState().isAuthenticated) router.push('/login'); }}
               className="w-full flex items-center gap-3 py-2.5 text-sm text-destructive hover:bg-muted rounded-md px-2 transition-colors duration-150"
             >
               <LogOut className="w-4 h-4" />
@@ -275,7 +296,14 @@ export default function SettingsPage() {
         </div>
 
         {/* Bottom Navigation */}
-        <NavigationRail orientation="horizontal" />
+        <NavigationRail
+          orientation="horizontal"
+          onManageApps={handleManageApps}
+          onInlineApp={handleInlineApp}
+          onCloseInlineApp={closeInlineApp}
+          activeAppId={inlineApp?.id ?? null}
+        />
+        <SidebarAppsModal isOpen={showAppsModal} onClose={closeAppsModal} />
       </div>
     );
   }
@@ -289,10 +317,19 @@ export default function SettingsPage() {
           collapsed
           quota={quota}
           isPushConnected={isPushConnected}
-          onLogout={() => { logout(); router.push('/login'); }}
+          onLogout={() => { logout(); if (!useAuthStore.getState().isAuthenticated) router.push('/login'); }}
+          onManageApps={handleManageApps}
+          onInlineApp={handleInlineApp}
+          onCloseInlineApp={closeInlineApp}
+          activeAppId={inlineApp?.id ?? null}
         />
       </div>
 
+      {inlineApp && (
+        <InlineAppView apps={loadedApps} activeAppId={inlineApp!.id} onClose={closeInlineApp} className="flex-1" />
+      )}
+      {!inlineApp && (
+      <>
       {/* Settings Sidebar */}
       <div
         className={cn(
@@ -380,6 +417,9 @@ export default function SettingsPage() {
           </div>
         </div>
       </div>
+      </>
+      )}
+      <SidebarAppsModal isOpen={showAppsModal} onClose={closeAppsModal} />
     </div>
   );
 }

app/api/auth/session/route.ts

@@ -2,7 +2,7 @@ import { NextRequest, NextResponse } from 'next/server';
 import { cookies } from 'next/headers';
 import { logger } from '@/lib/logger';
 import { encryptSession, decryptSession } from '@/lib/auth/crypto';
-import { SESSION_COOKIE, SESSION_COOKIE_MAX_AGE } from '@/lib/auth/session-cookie';
+import { SESSION_COOKIE_MAX_AGE, sessionCookieName } from '@/lib/auth/session-cookie';
 
 const COOKIE_OPTIONS = {
   httpOnly: true,
@@ -12,20 +12,30 @@ const COOKIE_OPTIONS = {
   maxAge: SESSION_COOKIE_MAX_AGE,
 };
 
+function getSlot(request: NextRequest): number {
+  const raw = request.nextUrl.searchParams.get('slot');
+  if (raw === null) return 0;
+  const slot = parseInt(raw, 10);
+  if (isNaN(slot) || slot < 0 || slot > 4) return 0;
+  return slot;
+}
+
 export async function POST(request: NextRequest) {
   try {
     if (process.env.OAUTH_ENABLED === 'true' && process.env.OAUTH_ONLY === 'true') {
       return NextResponse.json({ error: 'Basic authentication is disabled' }, { status: 403 });
     }
 
-    const { serverUrl, username, password } = await request.json();
+    const { serverUrl, username, password, slot: bodySlot } = await request.json();
     if (!serverUrl || !username || !password) {
       return NextResponse.json({ error: 'Missing required fields' }, { status: 400 });
     }
 
+    const slot = typeof bodySlot === 'number' && bodySlot >= 0 && bodySlot <= 4 ? bodySlot : getSlot(request);
+    const cookieName = sessionCookieName(slot);
     const token = encryptSession(serverUrl, username, password);
     const cookieStore = await cookies();
-    cookieStore.set(SESSION_COOKIE, token, COOKIE_OPTIONS);
+    cookieStore.set(cookieName, token, COOKIE_OPTIONS);
 
     return NextResponse.json({ ok: true });
   } catch (error) {
@@ -34,10 +44,12 @@ export async function POST(request: NextRequest) {
   }
 }
 
-export async function GET() {
+export async function GET(request: NextRequest) {
   try {
+    const slot = getSlot(request);
+    const cookieName = sessionCookieName(slot);
     const cookieStore = await cookies();
-    const token = cookieStore.get(SESSION_COOKIE)?.value;
+    const token = cookieStore.get(cookieName)?.value;
 
     if (!token) {
       return NextResponse.json({ error: 'No session' }, { status: 401 });
@@ -45,7 +57,7 @@ export async function GET() {
 
     const credentials = decryptSession(token);
     if (!credentials) {
-      cookieStore.delete(SESSION_COOKIE);
+      cookieStore.delete(cookieName);
       return NextResponse.json({ error: 'Invalid session' }, { status: 401 });
     }
 
@@ -58,10 +70,21 @@ export async function GET() {
   }
 }
 
-export async function DELETE() {
+export async function DELETE(request: NextRequest) {
   try {
     const cookieStore = await cookies();
-    cookieStore.delete(SESSION_COOKIE);
+    const all = request.nextUrl.searchParams.get('all') === 'true';
+
+    if (all) {
+      // Delete all session cookies (slots 0-4)
+      for (let i = 0; i <= 4; i++) {
+        cookieStore.delete(sessionCookieName(i));
+      }
+    } else {
+      const slot = getSlot(request);
+      cookieStore.delete(sessionCookieName(slot));
+    }
+
     return NextResponse.json({ ok: true });
   } catch (error) {
     logger.error('Session clear error', { error: error instanceof Error ? error.message : 'Unknown error' });

app/api/auth/token/route.ts

@@ -2,7 +2,7 @@ import { NextRequest, NextResponse } from 'next/server';
 import { cookies } from 'next/headers';
 import { logger } from '@/lib/logger';
 import { discoverOAuth } from '@/lib/oauth/discovery';
-import { REFRESH_TOKEN_COOKIE } from '@/lib/oauth/tokens';
+import { refreshTokenCookieName } from '@/lib/oauth/tokens';
 
 const CLIENT_SECRET = process.env.OAUTH_CLIENT_SECRET || '';
 
@@ -14,6 +14,15 @@ const COOKIE_OPTIONS = {
   maxAge: 30 * 24 * 60 * 60,
 };
 
+function getSlot(request: NextRequest): number {
+  const raw = request.nextUrl.searchParams.get('slot');
+  if (raw === null) return 0;
+  const slot = parseInt(raw, 10);
+  if (isNaN(slot) || slot < 0 || slot > 4) return 0;
+  return slot;
+}
+
+
 function getRequiredConfig() {
   const clientId = process.env.OAUTH_CLIENT_ID;
   const serverUrl = process.env.JMAP_SERVER_URL || process.env.NEXT_PUBLIC_JMAP_SERVER_URL;
@@ -53,12 +62,13 @@ function buildOAuthParams(base: Record<string, string>): URLSearchParams {
 
 export async function POST(request: NextRequest) {
   try {
-    const { code, code_verifier, redirect_uri } = await request.json();
+    const { code, code_verifier, redirect_uri, slot: bodySlot } = await request.json();
 
     if (!code || !code_verifier || !redirect_uri) {
       return NextResponse.json({ error: 'Missing required parameters' }, { status: 400 });
     }
 
+    const slot = typeof bodySlot === 'number' && bodySlot >= 0 && bodySlot <= 4 ? bodySlot : getSlot(request);
     const tokenEndpoint = await getTokenEndpoint();
 
     const params = buildOAuthParams({
@@ -93,8 +103,9 @@ export async function POST(request: NextRequest) {
     });
 
     if (tokens.refresh_token) {
+      const cookieName = refreshTokenCookieName(slot);
       const cookieStore = await cookies();
-      cookieStore.set(REFRESH_TOKEN_COOKIE, tokens.refresh_token, COOKIE_OPTIONS);
+      cookieStore.set(cookieName, tokens.refresh_token, COOKIE_OPTIONS);
     }
 
     return response;
@@ -104,10 +115,12 @@ export async function POST(request: NextRequest) {
   }
 }
 
-export async function PUT() {
+export async function PUT(request: NextRequest) {
   try {
+    const slot = getSlot(request);
+    const cookieName = refreshTokenCookieName(slot);
     const cookieStore = await cookies();
-    const refreshToken = cookieStore.get(REFRESH_TOKEN_COOKIE)?.value;
+    const refreshToken = cookieStore.get(cookieName)?.value;
 
     if (!refreshToken) {
       return NextResponse.json({ error: 'No refresh token' }, { status: 401 });
@@ -129,7 +142,7 @@ export async function PUT() {
     if (!tokenResponse.ok) {
       const errorText = await tokenResponse.text();
       logger.error('Token refresh failed', { status: tokenResponse.status, error: errorText });
-      cookieStore.delete(REFRESH_TOKEN_COOKIE);
+      cookieStore.delete(cookieName);
       return NextResponse.json({ error: 'Refresh failed' }, { status: 401 });
     }
 
@@ -141,7 +154,7 @@ export async function PUT() {
     }
 
     if (tokens.refresh_token) {
-      cookieStore.set(REFRESH_TOKEN_COOKIE, tokens.refresh_token, COOKIE_OPTIONS);
+      cookieStore.set(cookieName, tokens.refresh_token, COOKIE_OPTIONS);
     }
 
     return NextResponse.json({
@@ -154,10 +167,39 @@ export async function PUT() {
   }
 }
 
-export async function DELETE() {
+export async function DELETE(request: NextRequest) {
   try {
+    const all = request.nextUrl.searchParams.get('all') === 'true';
+
+    if (all) {
+      // Revoke and delete all refresh token cookies (slots 0-4)
+      const cookieStore = await cookies();
+      for (let i = 0; i <= 4; i++) {
+        const name = refreshTokenCookieName(i);
+        const token = cookieStore.get(name)?.value;
+        if (token) {
+          // Best-effort revocation
+          try {
+            const metadata = await getMetadata().catch(() => null);
+            if (metadata?.revocation_endpoint) {
+              const params = buildOAuthParams({ token, token_type_hint: 'refresh_token' });
+              await fetch(metadata.revocation_endpoint, {
+                method: 'POST',
+                headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
+                body: params.toString(),
+              }).catch(() => {});
+            }
+          } catch { /* best effort */ }
+          cookieStore.delete(name);
+        }
+      }
+      return NextResponse.json({ ok: true });
+    }
+
+    const slot = getSlot(request);
+    const cookieName = refreshTokenCookieName(slot);
     const cookieStore = await cookies();
-    const refreshToken = cookieStore.get(REFRESH_TOKEN_COOKIE)?.value;
+    const refreshToken = cookieStore.get(cookieName)?.value;
     const metadata = await getMetadata().catch((err) => {
       logger.warn('Failed to discover OAuth metadata during logout', {
         error: err instanceof Error ? err.message : 'Unknown error',
@@ -186,7 +228,7 @@ export async function DELETE() {
         }
       }
 
-      cookieStore.delete(REFRESH_TOKEN_COOKIE);
+      cookieStore.delete(cookieName);
     }
 
     let end_session_url: string | undefined;

app/api/caldav/discover/route.ts

@@ -0,0 +1,103 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { logger } from '@/lib/logger';
+import { getStalwartCredentials } from '@/lib/stalwart/credentials';
+
+interface DiscoveryAccountRequest {
+  key: string;
+  candidates: string[];
+}
+
+interface DiscoveryResult {
+  url: string | null;
+  resolvedAccount: string | null;
+}
+
+function buildPublicUrl(serverUrl: string, path: string): string {
+  return new URL(path, serverUrl).toString();
+}
+
+async function probeCalendarHome(serverUrl: string, authHeader: string, accountName: string): Promise<string | null> {
+  const targetUrl = buildPublicUrl(serverUrl, `/dav/cal/${encodeURIComponent(accountName)}`);
+  const response = await fetch(targetUrl, {
+    method: 'PROPFIND',
+    headers: {
+      Authorization: authHeader,
+      Depth: '0',
+      'Content-Type': 'application/xml; charset=utf-8',
+    },
+    body: `<?xml version="1.0" encoding="utf-8"?>
+<D:propfind xmlns:D="DAV:">
+  <D:prop>
+    <D:resourcetype/>
+    <D:displayname/>
+  </D:prop>
+</D:propfind>`,
+    redirect: 'manual',
+  });
+
+  if (response.status === 207) {
+    return targetUrl;
+  }
+
+  if (response.status >= 300 && response.status < 400) {
+    const location = response.headers.get('Location');
+    if (location) {
+      return new URL(location, targetUrl).toString();
+    }
+  }
+
+  return null;
+}
+
+export async function POST(request: NextRequest) {
+  try {
+    const creds = await getStalwartCredentials(request);
+    if (!creds) {
+      return NextResponse.json({ error: 'Not authenticated' }, { status: 401 });
+    }
+
+    const body = await request.json().catch(() => ({}));
+    const accounts = Array.isArray(body.accounts) ? body.accounts as DiscoveryAccountRequest[] : [];
+    const wellKnownUrl = buildPublicUrl(creds.serverUrl, '/.well-known/caldav');
+    const discovered: Record<string, DiscoveryResult> = {};
+
+    for (const account of accounts) {
+      if (!account?.key) continue;
+
+      const candidates = Array.from(new Set(
+        (account.candidates || [])
+          .map((candidate) => candidate?.trim())
+          .filter((candidate): candidate is string => Boolean(candidate))
+      ));
+
+      let url: string | null = null;
+      let resolvedAccount: string | null = null;
+
+      for (const candidate of candidates) {
+        try {
+          url = await probeCalendarHome(creds.serverUrl, creds.authHeader, candidate);
+          if (url) {
+            resolvedAccount = candidate;
+            break;
+          }
+        } catch (error) {
+          logger.warn('CalDAV discovery probe failed', {
+            accountKey: account.key,
+            candidate,
+            error: error instanceof Error ? error.message : 'Unknown',
+          });
+        }
+      }
+
+      discovered[account.key] = { url, resolvedAccount };
+    }
+
+    return NextResponse.json({
+      wellKnownUrl,
+      accounts: discovered,
+    });
+  } catch (error) {
+    logger.error('CalDAV discovery failed', { error: error instanceof Error ? error.message : 'Unknown' });
+    return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
+  }
+}

app/api/config/route.ts

@@ -26,6 +26,9 @@ export async function GET() {
     settingsSyncEnabled: process.env.SETTINGS_SYNC_ENABLED === 'true' && !!process.env.SESSION_SECRET,
     stalwartFeaturesEnabled: process.env.STALWART_FEATURES !== 'false',
     devMode: process.env.DEV_MOCK_JMAP === 'true',
+    faviconUrl: process.env.FAVICON_URL || '/branding/Bulwark_Favicon.svg',
+    appLogoLightUrl: process.env.APP_LOGO_LIGHT_URL || '',
+    appLogoDarkUrl: process.env.APP_LOGO_DARK_URL || '',
     loginLogoLightUrl: process.env.LOGIN_LOGO_LIGHT_URL || '/branding/Bulwark_Logo_Color.svg',
     loginLogoDarkUrl: process.env.LOGIN_LOGO_DARK_URL || '/branding/Bulwark_Logo_White.svg',
     loginCompanyName: process.env.LOGIN_COMPANY_NAME || '',

app/api/settings/route.ts

@@ -47,7 +47,9 @@ export async function GET(request: NextRequest) {
     }
     return NextResponse.json({ settings });
   } catch (error) {
-    logger.error('Settings load error', { error: error instanceof Error ? error.message : 'Unknown error' });
+    const message = error instanceof Error ? error.message : 'Unknown error';
+    const code = (error as NodeJS.ErrnoException).code;
+    logger.error('Settings load error', { error: message, code });
     return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
   }
 }
@@ -74,7 +76,9 @@ export async function POST(request: NextRequest) {
     await saveUserSettings(username, serverUrl, settings);
     return NextResponse.json({ ok: true });
   } catch (error) {
-    logger.error('Settings save error', { error: error instanceof Error ? error.message : 'Unknown error' });
+    const message = error instanceof Error ? error.message : 'Unknown error';
+    const code = (error as NodeJS.ErrnoException).code;
+    logger.error('Settings save error', { error: message, code });
     return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
   }
 }

app/layout.tsx

@@ -14,10 +14,15 @@ const geistMono = Geist_Mono({
   subsets: ["latin"],
 });
 
-export const metadata: Metadata = {
+export async function generateMetadata(): Promise<Metadata> {
-  title: "Bulwark Webmail",
+  const faviconUrl = process.env.FAVICON_URL;
-  description: "Minimalist webmail client using JMAP protocol",
+
-};
+  return {
+    title: process.env.APP_NAME || process.env.NEXT_PUBLIC_APP_NAME || "Webmail",
+    description: "Minimalist webmail client using JMAP protocol",
+    ...(faviconUrl ? { icons: { icon: faviconUrl } } : {}),
+  };
+}
 
 export default async function RootLayout({
   children,

components/calendar/calendar-agenda-view.tsx

@@ -6,7 +6,7 @@ import { format, parseISO, isToday, isTomorrow } from "date-fns";
 import { Calendar as CalendarIcon, MapPin, Users } from "lucide-react";
 import { cn } from "@/lib/utils";
 import { parseDuration, getEventColor } from "./event-card";
-import { getEventDayBounds } from "@/lib/calendar-utils";
+import { getEventDayBounds, getPrimaryCalendarId } from "@/lib/calendar-utils";
 import { getParticipantCount } from "@/lib/calendar-participants";
 import type { CalendarEvent, Calendar } from "@/lib/jmap/types";
 
@@ -113,8 +113,8 @@ export function CalendarAgendaView({
 
           <div className="divide-y divide-border">
             {group.events.map((ev) => {
-              const calId = Object.keys(ev.calendarIds)[0];
+              const calId = getPrimaryCalendarId(ev);
-              const calendar = calendarMap.get(calId);
+              const calendar = calId ? calendarMap.get(calId) : undefined;
               const color = getEventColor(ev, calendar);
               const start = parseISO(ev.start);
               const durMin = parseDuration(ev.duration);

components/calendar/calendar-day-view.tsx

@@ -6,7 +6,7 @@ import { format, isToday, parseISO } from "date-fns";
 import { cn } from "@/lib/utils";
 import { EventCard, parseDuration } from "./event-card";
 import { QuickEventInput } from "./quick-event-input";
-import { getEventDayBounds, layoutOverlappingEvents, formatSnapTime } from "@/lib/calendar-utils";
+import { formatSnapTime, getEventDayBounds, getPrimaryCalendarId, layoutOverlappingEvents } from "@/lib/calendar-utils";
 import type { CalendarEvent, Calendar } from "@/lib/jmap/types";
 import { useTimeGridInteractions } from "@/hooks/use-time-grid-interactions";
 
@@ -127,12 +127,12 @@ export function CalendarDayView({
           <div className="text-[10px] text-muted-foreground mb-1">{t("events.all_day")}</div>
           <div className="space-y-1">
             {allDayEvents.map((ev) => {
-              const calId = Object.keys(ev.calendarIds)[0];
+              const calId = getPrimaryCalendarId(ev);
               return (
                 <EventCard
                   key={ev.id}
                   event={ev}
-                  calendar={calendarMap.get(calId)}
+                  calendar={calId ? calendarMap.get(calId) : undefined}
                   variant="chip"
                   onClick={(rect) => onSelectEvent(ev, rect)}
                   onMouseEnter={(rect) => onHoverEvent?.(ev, rect)}
@@ -192,7 +192,7 @@ export function CalendarDayView({
               const top = (startMin / 60) * HOUR_HEIGHT;
               const baseHeight = Math.max(24, (durMin / 60) * HOUR_HEIGHT);
               const height = resizeVisual?.eventId === ev.id ? resizeVisual.heightPx : baseHeight;
-              const calId = Object.keys(ev.calendarIds)[0];
+              const calId = getPrimaryCalendarId(ev);
               const leftPct = (column / totalColumns) * 100;
               const widthPct = (1 / totalColumns) * 100;
 
@@ -205,7 +205,7 @@ export function CalendarDayView({
                 >
                   <EventCard
                     event={ev}
-                    calendar={calendarMap.get(calId)}
+                    calendar={calId ? calendarMap.get(calId) : undefined}
                     variant="block"
                     onClick={(rect) => onSelectEvent(ev, rect)}
                     onMouseEnter={(rect) => onHoverEvent?.(ev, rect)}

components/calendar/calendar-month-view.tsx

@@ -8,7 +8,7 @@ import {
 } from "date-fns";
 import { cn } from "@/lib/utils";
 import { EventCard } from "./event-card";
-import { buildWeekSegments, getEventDayBounds } from "@/lib/calendar-utils";
+import { buildWeekSegments, getEventDayBounds, getPrimaryCalendarId } from "@/lib/calendar-utils";
 import type { CalendarEvent, Calendar } from "@/lib/jmap/types";
 import { useAuthStore } from "@/stores/auth-store";
 import { useCalendarStore } from "@/stores/calendar-store";
@@ -22,6 +22,7 @@ interface CalendarMonthViewProps {
   onSelectEvent: (event: CalendarEvent, anchorRect: DOMRect) => void;
   onHoverEvent?: (event: CalendarEvent, anchorRect: DOMRect) => void;
   onHoverLeave?: () => void;
+  onCreateAtTime?: (date: Date) => void;
   firstDayOfWeek?: number;
   isMobile?: boolean;
 }
@@ -34,6 +35,7 @@ export function CalendarMonthView({
   onSelectEvent,
   onHoverEvent,
   onHoverLeave,
+  onCreateAtTime,
   firstDayOfWeek = 1,
   isMobile,
 }: CalendarMonthViewProps) {
@@ -165,6 +167,7 @@ export function CalendarMonthView({
                   aria-selected={selected}
                   aria-label={fullDateLabel}
                   onClick={() => onSelectDate(day)}
+                  onDoubleClick={() => onCreateAtTime?.(day)}
                   onDragOver={(e) => handleCellDragOver(e, key)}
                   onDragLeave={handleCellDragLeave}
                   onDrop={(e) => handleCellDrop(e, day)}
@@ -194,8 +197,8 @@ export function CalendarMonthView({
                     dayEvents.length > 0 && (
                       <div className="flex items-center justify-center gap-0.5 flex-wrap">
                         {dayEvents.slice(0, 3).map((ev) => {
-                          const calId = Object.keys(ev.calendarIds)[0];
+                          const calId = getPrimaryCalendarId(ev);
-                          const cal = calendarMap.get(calId);
+                          const cal = calId ? calendarMap.get(calId) : undefined;
                           const evColor = ev.color || cal?.color || "#3b82f6";
                           return (
                             <span
@@ -219,7 +222,7 @@ export function CalendarMonthView({
             {!isMobile && segments.length > 0 && (
               <div className="absolute inset-x-0 pointer-events-none" style={{ top: 30 }}>
                 {segments.map((segment) => {
-                  const calId = Object.keys(segment.event.calendarIds)[0];
+                  const calId = getPrimaryCalendarId(segment.event);
                   return (
                     <div
                       key={`${segment.event.id}-${segment.startIndex}-${segment.row}`}
@@ -233,7 +236,7 @@ export function CalendarMonthView({
                     >
                       <EventCard
                         event={segment.event}
-                        calendar={calendarMap.get(calId)}
+                        calendar={calId ? calendarMap.get(calId) : undefined}
                         variant="span"
                         continuesBefore={segment.continuesBefore}
                         continuesAfter={segment.continuesAfter}

components/calendar/calendar-sidebar-panel.tsx

@@ -1,12 +1,13 @@
 "use client";
 
-import { useState, useRef, useEffect } from "react";
+import { useState, useRef, useEffect, useMemo } from "react";
 import { useTranslations } from "next-intl";
-import { Globe, Plus, RefreshCw, Trash2 } from "lucide-react";
+import { Globe, Plus, RefreshCw, Share2, Trash2 } from "lucide-react";
-import { cn } from "@/lib/utils";
+import { cn, formatDateTime } from "@/lib/utils";
 import type { Calendar } from "@/lib/jmap/types";
 import { CalendarColorPicker } from "@/components/settings/calendar-management-settings";
 import { useCalendarStore } from "@/stores/calendar-store";
+import { useSettingsStore } from "@/stores/settings-store";
 import { toast } from "@/stores/toast-store";
 import type { JMAPClient } from "@/lib/jmap/client";
 
@@ -33,6 +34,7 @@ export function CalendarSidebarPanel({
   const icalSubscriptions = useCalendarStore((s) => s.icalSubscriptions);
   const refreshICalSubscription = useCalendarStore((s) => s.refreshICalSubscription);
   const removeICalSubscription = useCalendarStore((s) => s.removeICalSubscription);
+  const timeFormat = useSettingsStore((s) => s.timeFormat);
 
   const [colorPickerId, setColorPickerId] = useState<string | null>(null);
   const [contextMenuCalId, setContextMenuCalId] = useState<string | null>(null);
@@ -40,6 +42,20 @@ export function CalendarSidebarPanel({
   const colorPickerRef = useRef<HTMLDivElement>(null);
   const contextMenuRef = useRef<HTMLDivElement>(null);
 
+  const personalCalendars = useMemo(() => calendars.filter(c => !c.isShared), [calendars]);
+  const sharedAccountGroups = useMemo(() => {
+    const shared = calendars.filter(c => c.isShared);
+    const groups = new Map<string, { accountName: string; calendars: Calendar[] }>();
+    for (const cal of shared) {
+      const key = cal.accountId || cal.accountName || cal.id;
+      if (!groups.has(key)) {
+        groups.set(key, { accountName: cal.accountName || key, calendars: [] });
+      }
+      groups.get(key)!.calendars.push(cal);
+    }
+    return Array.from(groups.values());
+  }, [calendars]);
+
   useEffect(() => {
     if (!colorPickerId && !contextMenuCalId) return;
     const handleClick = (e: MouseEvent) => {
@@ -95,108 +111,122 @@ export function CalendarSidebarPanel({
 
   if (calendars.length === 0 && !onSubscribe) return null;
 
+  const renderCalendarItem = (cal: Calendar) => {
+    const isVisible = selectedCalendarIds.includes(cal.id);
+    const color = cal.color || "#3b82f6";
+
+    return (
+      <div key={cal.id} className="relative">
+        <button
+          onClick={() => onToggleVisibility(cal.id)}
+          onContextMenu={(e) => {
+            e.preventDefault();
+            if (isSubscriptionCalendar(cal.id) && client) {
+              setContextMenuCalId(contextMenuCalId === cal.id ? null : cal.id);
+              setColorPickerId(null);
+            } else if (onColorChange) {
+              setColorPickerId(colorPickerId === cal.id ? null : cal.id);
+              setContextMenuCalId(null);
+            }
+          }}
+          className={cn(
+            "flex items-center gap-2 w-full px-1.5 py-1 rounded-md text-sm transition-colors duration-150",
+            "hover:bg-muted"
+          )}
+        >
+          <span
+            className={cn(
+              "w-3 h-3 rounded-sm border-2 flex-shrink-0 transition-colors",
+              isVisible ? "border-transparent" : "border-muted-foreground/40 bg-transparent"
+            )}
+            style={isVisible ? { backgroundColor: color, borderColor: color } : undefined}
+          />
+          <span className={cn("truncate", !isVisible && "text-muted-foreground")}>
+            {cal.name}
+          </span>
+          {isSubscriptionCalendar(cal.id) && (
+            <>
+              <Globe className="w-3 h-3 text-muted-foreground flex-shrink-0" />
+              {refreshingSubId === getSubscriptionForCalendar(cal.id)?.id && (
+                <RefreshCw className="w-3 h-3 text-muted-foreground flex-shrink-0 animate-spin" />
+              )}
+            </>
+          )}
+        </button>
+
+        {/* Subscription context menu on right-click */}
+        {contextMenuCalId === cal.id && isSubscriptionCalendar(cal.id) && client && (() => {
+          const sub = getSubscriptionForCalendar(cal.id);
+          if (!sub) return null;
+          return (
+            <div
+              ref={contextMenuRef}
+              className="absolute left-6 top-full mt-1 z-50 bg-background border border-border rounded-lg shadow-lg py-1 w-48"
+            >
+              <button
+                onClick={() => handleRefreshSubscription(sub.id)}
+                className="flex items-center gap-2 w-full px-3 py-1.5 text-sm hover:bg-muted transition-colors"
+              >
+                <RefreshCw className="w-3.5 h-3.5" />
+                {tSub('refresh')}
+              </button>
+              <button
+                onClick={() => handleUnsubscribe(sub.id)}
+                className="flex items-center gap-2 w-full px-3 py-1.5 text-sm text-destructive hover:bg-destructive/10 transition-colors"
+              >
+                <Trash2 className="w-3.5 h-3.5" />
+                {tSub('unsubscribe')}
+              </button>
+              {sub.lastRefreshed && (
+                <div className="px-3 py-1.5 text-xs text-muted-foreground border-t border-border mt-1 pt-1">
+                  {tSub('last_refreshed', { time: formatDateTime(sub.lastRefreshed, timeFormat, { month: 'short', day: 'numeric', year: 'numeric' }) })}
+                </div>
+              )}
+            </div>
+          );
+        })()}
+
+        {/* Color picker popover on right-click */}
+        {colorPickerId === cal.id && onColorChange && (
+          <div
+            ref={colorPickerRef}
+            className="absolute left-6 top-full mt-1 z-50 bg-background border border-border rounded-lg shadow-lg p-3 w-56"
+          >
+            <p className="text-xs font-medium text-muted-foreground mb-2">{t("management.change_color")}</p>
+            <CalendarColorPicker
+              value={color}
+              onChange={(c) => {
+                onColorChange(cal.id, c);
+                setColorPickerId(null);
+              }}
+              allowCustom
+            />
+          </div>
+        )}
+      </div>
+    );
+  };
+
   return (
     <div className="mt-4">
       <h3 className="text-xs font-medium text-muted-foreground uppercase tracking-wider mb-2 px-1">
         {t("my_calendars")}
       </h3>
       <div className="space-y-0.5">
-        {calendars.map((cal) => {
+        {personalCalendars.map(renderCalendarItem)}
-          const isVisible = selectedCalendarIds.includes(cal.id);
-          const color = cal.color || "#3b82f6";
-
-          return (
-            <div key={cal.id} className="relative">
-              <button
-                onClick={() => onToggleVisibility(cal.id)}
-                onContextMenu={(e) => {
-                  e.preventDefault();
-                  if (isSubscriptionCalendar(cal.id) && client) {
-                    setContextMenuCalId(contextMenuCalId === cal.id ? null : cal.id);
-                    setColorPickerId(null);
-                  } else if (onColorChange) {
-                    setColorPickerId(colorPickerId === cal.id ? null : cal.id);
-                    setContextMenuCalId(null);
-                  }
-                }}
-                className={cn(
-                  "flex items-center gap-2 w-full px-1.5 py-1 rounded-md text-sm transition-colors duration-150",
-                  "hover:bg-muted"
-                )}
-              >
-                <span
-                  className={cn(
-                    "w-3 h-3 rounded-sm border-2 flex-shrink-0 transition-colors",
-                    isVisible ? "border-transparent" : "border-muted-foreground/40 bg-transparent"
-                  )}
-                  style={isVisible ? { backgroundColor: color, borderColor: color } : undefined}
-                />
-                <span className={cn("truncate", !isVisible && "text-muted-foreground")}>
-                  {cal.name}
-                </span>
-                {isSubscriptionCalendar(cal.id) && (
-                  <>
-                    <Globe className="w-3 h-3 text-muted-foreground flex-shrink-0" />
-                    {refreshingSubId === getSubscriptionForCalendar(cal.id)?.id && (
-                      <RefreshCw className="w-3 h-3 text-muted-foreground flex-shrink-0 animate-spin" />
-                    )}
-                  </>
-                )}
-              </button>
-
-              {/* Subscription context menu on right-click */}
-              {contextMenuCalId === cal.id && isSubscriptionCalendar(cal.id) && client && (() => {
-                const sub = getSubscriptionForCalendar(cal.id);
-                if (!sub) return null;
-                return (
-                  <div
-                    ref={contextMenuRef}
-                    className="absolute left-6 top-full mt-1 z-50 bg-background border border-border rounded-lg shadow-lg py-1 w-48"
-                  >
-                    <button
-                      onClick={() => handleRefreshSubscription(sub.id)}
-                      className="flex items-center gap-2 w-full px-3 py-1.5 text-sm hover:bg-muted transition-colors"
-                    >
-                      <RefreshCw className="w-3.5 h-3.5" />
-                      {tSub('refresh')}
-                    </button>
-                    <button
-                      onClick={() => handleUnsubscribe(sub.id)}
-                      className="flex items-center gap-2 w-full px-3 py-1.5 text-sm text-destructive hover:bg-destructive/10 transition-colors"
-                    >
-                      <Trash2 className="w-3.5 h-3.5" />
-                      {tSub('unsubscribe')}
-                    </button>
-                    {sub.lastRefreshed && (
-                      <div className="px-3 py-1.5 text-xs text-muted-foreground border-t border-border mt-1 pt-1">
-                        {tSub('last_refreshed', { time: new Date(sub.lastRefreshed).toLocaleString() })}
-                      </div>
-                    )}
-                  </div>
-                );
-              })()}
-
-              {/* Color picker popover on right-click */}
-              {colorPickerId === cal.id && onColorChange && (
-                <div
-                  ref={colorPickerRef}
-                  className="absolute left-6 top-full mt-1 z-50 bg-background border border-border rounded-lg shadow-lg p-3 w-56"
-                >
-                  <p className="text-xs font-medium text-muted-foreground mb-2">{t("management.change_color")}</p>
-                  <CalendarColorPicker
-                    value={color}
-                    onChange={(c) => {
-                      onColorChange(cal.id, c);
-                      setColorPickerId(null);
-                    }}
-                    allowCustom
-                  />
-                </div>
-              )}
-            </div>
-          );
-        })}
       </div>
+
+      {sharedAccountGroups.map((group) => (
+        <div key={group.accountName} className="mt-4">
+          <h3 className="text-xs font-medium text-muted-foreground uppercase tracking-wider mb-2 px-1 flex items-center gap-1.5">
+            <Share2 className="w-3 h-3" />
+            {group.accountName}
+          </h3>
+          <div className="space-y-0.5">
+            {group.calendars.map(renderCalendarItem)}
+          </div>
+        </div>
+      ))}
     </div>
   );
 }

components/calendar/calendar-toolbar.tsx

@@ -153,7 +153,7 @@ export function CalendarToolbar({
                 {t("my_calendars")}
               </h3>
               <div className="space-y-0.5">
-                {calendars.map((cal) => {
+                {calendars.filter(c => !c.isShared).map((cal) => {
                   const isVisible = selectedCalendarIds.includes(cal.id);
                   const color = cal.color || "#3b82f6";
                   return (
@@ -179,6 +179,49 @@ export function CalendarToolbar({
                   );
                 })}
               </div>
+              {(() => {
+                const shared = calendars.filter(c => c.isShared);
+                const groups = new Map<string, { accountName: string; cals: typeof shared }>();
+                for (const c of shared) {
+                  const key = c.accountId || c.accountName || c.id;
+                  if (!groups.has(key)) groups.set(key, { accountName: c.accountName || key, cals: [] });
+                  groups.get(key)!.cals.push(c);
+                }
+                return Array.from(groups.values()).map((group) => (
+                  <div key={group.accountName} className="mt-2">
+                    <h3 className="text-xs font-medium text-muted-foreground uppercase tracking-wider mb-1 px-1">
+                      {group.accountName}
+                    </h3>
+                    <div className="space-y-0.5">
+                      {group.cals.map((cal) => {
+                        const isVisible = selectedCalendarIds.includes(cal.id);
+                        const color = cal.color || "#3b82f6";
+                        return (
+                          <button
+                            key={cal.id}
+                            onClick={() => onToggleVisibility(cal.id)}
+                            className={cn(
+                              "flex items-center gap-2 w-full px-2 py-2 rounded-md text-sm transition-colors duration-150 touch-manipulation",
+                              "hover:bg-muted"
+                            )}
+                          >
+                            <span
+                              className={cn(
+                                "w-3.5 h-3.5 rounded-sm border-2 flex-shrink-0 transition-colors",
+                                isVisible ? "border-transparent" : "border-muted-foreground/40 bg-transparent"
+                              )}
+                              style={isVisible ? { backgroundColor: color, borderColor: color } : undefined}
+                            />
+                            <span className={cn("truncate", !isVisible && "text-muted-foreground")}>
+                              {cal.name}
+                            </span>
+                          </button>
+                        );
+                      })}
+                    </div>
+                  </div>
+                ));
+              })()}
             </div>
           )}
         </div>

components/calendar/calendar-week-view.tsx

@@ -8,7 +8,7 @@ import {
 import { cn } from "@/lib/utils";
 import { EventCard, parseDuration } from "./event-card";
 import { QuickEventInput } from "./quick-event-input";
-import { buildWeekSegments, getEventDayBounds, layoutOverlappingEvents, formatSnapTime } from "@/lib/calendar-utils";
+import { buildWeekSegments, formatSnapTime, getEventDayBounds, getPrimaryCalendarId, layoutOverlappingEvents } from "@/lib/calendar-utils";
 import type { CalendarEvent, Calendar } from "@/lib/jmap/types";
 import { useTimeGridInteractions } from "@/hooks/use-time-grid-interactions";
 
@@ -162,7 +162,7 @@ export function CalendarWeekView({
 
             <div className="absolute inset-0 pointer-events-none">
               {allDaySegments.map((segment) => {
-                const calId = Object.keys(segment.event.calendarIds)[0];
+                const calId = getPrimaryCalendarId(segment.event);
                 return (
                   <div
                     key={`${segment.event.id}-${segment.startIndex}-${segment.row}`}
@@ -176,7 +176,7 @@ export function CalendarWeekView({
                   >
                     <EventCard
                       event={segment.event}
-                      calendar={calendarMap.get(calId)}
+                      calendar={calId ? calendarMap.get(calId) : undefined}
                       variant="span"
                       continuesBefore={segment.continuesBefore}
                       continuesAfter={segment.continuesAfter}
@@ -284,7 +284,7 @@ export function CalendarWeekView({
                     const top = (startMin / 60) * HOUR_HEIGHT;
                     const baseHeight = Math.max(20, (durMin / 60) * HOUR_HEIGHT);
                     const height = resizeVisual?.eventId === ev.id ? resizeVisual.heightPx : baseHeight;
-                    const calId = Object.keys(ev.calendarIds)[0];
+                    const calId = getPrimaryCalendarId(ev);
                     const leftPct = (column / totalColumns) * 100;
                     const widthPct = (1 / totalColumns) * 100;
 
@@ -297,7 +297,7 @@ export function CalendarWeekView({
                       >
                         <EventCard
                           event={ev}
-                          calendar={calendarMap.get(calId)}
+                          calendar={calId ? calendarMap.get(calId) : undefined}
                           variant="block"
                           onClick={(rect) => onSelectEvent(ev, rect)}
                           onMouseEnter={(rect) => onHoverEvent?.(ev, rect)}

components/calendar/event-card.tsx

@@ -7,6 +7,7 @@ import type { CalendarEvent, Calendar } from "@/lib/jmap/types";
 import { format, parseISO } from "date-fns";
 import { Users } from "lucide-react";
 import { getParticipantCount } from "@/lib/calendar-participants";
+import { useSettingsStore } from "@/stores/settings-store";
 
 interface EventCardProps {
   event: CalendarEvent;
@@ -68,11 +69,13 @@ export function EventCard({ event, calendar, variant, onClick, onMouseEnter, onM
   const [isBeingDragged, setIsBeingDragged] = useState(false);
   const color = getEventColor(event, calendar);
   const startDate = parseISO(event.start);
+  const timeFormat = useSettingsStore((state) => state.timeFormat);
+  const timeFmt = timeFormat === "12h" ? "h:mm a" : "HH:mm";
 
   const calendarName = calendar?.name || "";
   const durationMinutes = parseDuration(event.duration);
   const endTime = new Date(startDate.getTime() + durationMinutes * 60000);
-  const timeString = `${format(startDate, "HH:mm")} – ${format(endTime, "HH:mm")}`;
+  const timeString = `${format(startDate, timeFmt)} – ${format(endTime, timeFmt)}`;
   const ariaLabel = `${event.title || t("events.no_title")}, ${timeString}${calendarName ? `, ${calendarName}` : ""}`;
 
   const handleDragStart = useCallback((e: DragEvent) => {

components/calendar/event-modal.tsx

@@ -8,7 +8,7 @@ import { X, Trash2, Check, Users, CalendarDays, Copy, Pencil, Clock, MapPin, Vid
 import { format, parseISO, addHours, addDays } from "date-fns";
 import type { CalendarEvent, Calendar, CalendarParticipant } from "@/lib/jmap/types";
 import { parseDuration, getEventColor } from "./event-card";
-import { buildAllDayDuration, getEventDisplayEndDate } from "@/lib/calendar-utils";
+import { buildAllDayDuration, getEventDisplayEndDate, getPrimaryCalendarId } from "@/lib/calendar-utils";
 import { ParticipantInput } from "./participant-input";
 import {
   isOrganizer,
@@ -18,13 +18,14 @@ import {
   getStatusCounts,
   buildParticipantMap,
 } from "@/lib/calendar-participants";
+import { useSettingsStore } from "@/stores/settings-store";
 
 interface EventModalProps {
   event?: CalendarEvent | null;
   calendars: Calendar[];
   defaultDate?: Date;
   defaultEndDate?: Date;
-  onSave: (data: Partial<CalendarEvent>, sendSchedulingMessages?: boolean) => void;
+  onSave: (data: Partial<CalendarEvent>, sendSchedulingMessages?: boolean) => void | Promise<void>;
   onDelete?: (id: string, sendSchedulingMessages?: boolean) => void;
   onDuplicate?: (data: Partial<CalendarEvent>) => void;
   onRsvp?: (eventId: string, participantId: string, status: CalendarParticipant['participationStatus']) => void;
@@ -108,6 +109,8 @@ export function EventModal({
   isMobile = false,
 }: EventModalProps) {
   const t = useTranslations("calendar");
+  const timeFormat = useSettingsStore((s) => s.timeFormat);
+  const timeDisplayFmt = timeFormat === "12h" ? "h:mm a" : "HH:mm";
   const isEdit = !!event;
   const [mode, setMode] = useState<"view" | "edit">(isEdit ? "view" : "edit");
 
@@ -181,7 +184,7 @@ export function EventModal({
   const [endTime, setEndTime] = useState(formatTimeInput(getInitialEnd()));
   const [allDay, setAllDay] = useState(event?.showWithoutTime || false);
   const [calendarId, setCalendarId] = useState<string>(() => {
-    if (event?.calendarIds) return Object.keys(event.calendarIds)[0] || calendars[0]?.id || "";
+    if (event?.calendarIds) return getPrimaryCalendarId(event) || calendars[0]?.id || "";
     const defaultCal = calendars.find(c => c.isDefault);
     return defaultCal?.id || calendars[0]?.id || "";
   });
@@ -206,6 +209,7 @@ export function EventModal({
     return "none";
   });
   const [showDeleteConfirm, setShowDeleteConfirm] = useState(false);
+  const [isSaving, setIsSaving] = useState(false);
 
   const [attendees, setAttendees] = useState<{ name: string; email: string }[]>(() => {
     if (!event?.participants) return [];
@@ -228,9 +232,9 @@ export function EventModal({
     setAttendees(prev => prev.filter(a => a.email.toLowerCase() !== email.toLowerCase()));
   }, []);
 
-  const handleSave = useCallback(() => {
+  const handleSave = useCallback(async () => {
     const trimmedTitle = title.trim();
-    if (!trimmedTitle) return;
+    if (!trimmedTitle || isSaving) return;
     if (trimmedTitle.length > 500 || description.trim().length > 10000 || location.trim().length > 500) return;
 
     const startStr = allDay
@@ -340,8 +344,13 @@ export function EventModal({
     }
 
     const shouldSendScheduling = attendees.length > 0 && sendInvitations;
-    onSave(data, shouldSendScheduling);
+    setIsSaving(true);
-  }, [title, description, location, startDate, startTime, endDate, endTime, allDay, calendarId, recurrence, alert, attendees, sendInvitations, currentUserEmails, existingParticipants, event, onSave]);
+    try {
+      await onSave(data, shouldSendScheduling);
+    } finally {
+      setIsSaving(false);
+    }
+  }, [title, description, location, startDate, startTime, endDate, endTime, allDay, calendarId, recurrence, alert, attendees, sendInvitations, currentUserEmails, existingParticipants, event, onSave, isSaving]);
 
   const handleRsvp = useCallback((status: CalendarParticipant['participationStatus']) => {
     if (!event || !userParticipantId || !onRsvp) return;
@@ -452,7 +461,7 @@ export function EventModal({
               <span className="font-medium">{format(startD, "EEE, MMM d, yyyy")}</span>
               {!event.showWithoutTime && (
                 <span className="text-muted-foreground ml-2">
-                  {format(startD, "HH:mm")} – {format(endD, "HH:mm")}
+                  {format(startD, timeDisplayFmt)} – {format(endD, timeDisplayFmt)}
                 </span>
               )}
             </div>
@@ -576,7 +585,7 @@ export function EventModal({
                   <span className="text-muted-foreground ml-1.5">{t("events.all_day")}</span>
                 ) : (
                   <div className="text-muted-foreground">
-                    {format(startD, "HH:mm")} – {format(endD, "HH:mm")}
+                    {format(startD, timeDisplayFmt)} – {format(endD, timeDisplayFmt)}
                     <span className="ml-1.5 text-xs">({formatDurationDisplay(durMin)})</span>
                   </div>
                 )}
@@ -942,7 +951,7 @@ export function EventModal({
             <Button variant="outline" onClick={isEdit ? () => setMode("view") : onClose}>
               {t("form.cancel")}
             </Button>
-            <Button onClick={handleSave} disabled={!title.trim()}>
+            <Button onClick={handleSave} disabled={!title.trim() || isSaving}>
               {t("form.save")}
             </Button>
           </div>

components/calendar/ical-import-modal.tsx

@@ -8,6 +8,7 @@ import { format, parseISO } from "date-fns";
 import type { CalendarEvent, Calendar } from "@/lib/jmap/types";
 import type { JMAPClient } from "@/lib/jmap/client";
 import { useCalendarStore } from "@/stores/calendar-store";
+import { useSettingsStore } from "@/stores/settings-store";
 import { toast } from "@/stores/toast-store";
 
 interface ICalImportModalProps {
@@ -28,6 +29,7 @@ export function ICalImportModal({ calendars, client, onClose }: ICalImportModalP
   const tCommon = useTranslations("common");
   const tForm = useTranslations("calendar.form");
   const importEvents = useCalendarStore((s) => s.importEvents);
+  const timeFormat = useSettingsStore((s) => s.timeFormat);
 
   const [step, setStep] = useState<ImportStep>("select");
   const [parsedEvents, setParsedEvents] = useState<Partial<CalendarEvent>[]>([]);
@@ -194,9 +196,10 @@ export function ICalImportModal({ calendars, client, onClose }: ICalImportModalP
     if (!event.start) return "";
     try {
       const date = parseISO(event.start);
+      const timeFmt = timeFormat === "12h" ? "h:mm a" : "HH:mm";
       return event.showWithoutTime
         ? format(date, "MMM d, yyyy")
-        : format(date, "MMM d, yyyy HH:mm");
+        : format(date, `MMM d, yyyy ${timeFmt}`);
     } catch {
       return event.start;
     }

components/calendar/task-list-view.tsx

@@ -0,0 +1,203 @@
+"use client";
+
+import { useMemo, useCallback } from "react";
+import { useTranslations } from "next-intl";
+import { format, parseISO, isPast, isToday, isTomorrow } from "date-fns";
+import { Check, Circle, Flag, CalendarDays, ListTodo } from "lucide-react";
+import { cn } from "@/lib/utils";
+import type { CalendarTask, Calendar } from "@/lib/jmap/types";
+import type { TaskViewFilter } from "@/stores/task-store";
+import { useSettingsStore } from "@/stores/settings-store";
+
+interface TaskListViewProps {
+  tasks: CalendarTask[];
+  calendars: Calendar[];
+  selectedCalendarIds: string[];
+  filter: TaskViewFilter;
+  showCompleted: boolean;
+  onSelectTask: (task: CalendarTask) => void;
+  onToggleComplete: (task: CalendarTask) => void;
+  selectedTaskId?: string | null;
+}
+
+function getTaskPriorityIcon(priority: number) {
+  if (priority >= 1 && priority <= 4) return <Flag className="h-3.5 w-3.5 text-red-500" />;
+  if (priority === 5) return <Flag className="h-3.5 w-3.5 text-orange-500" />;
+  if (priority >= 6 && priority <= 9) return <Flag className="h-3.5 w-3.5 text-gray-400" />;
+  return null;
+}
+
+function getDueDateLabel(due: string, showWithoutTime: boolean, t: ReturnType<typeof useTranslations>, timeFormat: string): { label: string; className: string } {
+  const dueDate = parseISO(due);
+  const overdue = isPast(dueDate) && !isToday(dueDate);
+
+  if (isToday(dueDate)) {
+    return {
+      label: t("tasks.due_today"),
+      className: "text-blue-600 dark:text-blue-400",
+    };
+  }
+  if (isTomorrow(dueDate)) {
+    return {
+      label: t("tasks.due_tomorrow"),
+      className: "text-muted-foreground",
+    };
+  }
+  if (overdue) {
+    return {
+      label: t("tasks.overdue"),
+      className: "text-red-600 dark:text-red-400",
+    };
+  }
+
+  const formatted = showWithoutTime
+    ? format(dueDate, "MMM d")
+    : format(dueDate, timeFormat === "12h" ? "MMM d, h:mm a" : "MMM d, HH:mm");
+
+  return {
+    label: formatted,
+    className: "text-muted-foreground",
+  };
+}
+
+export function TaskListView({
+  tasks,
+  calendars,
+  selectedCalendarIds,
+  filter,
+  showCompleted,
+  onSelectTask,
+  onToggleComplete,
+  selectedTaskId,
+}: TaskListViewProps) {
+  const t = useTranslations("calendar");
+  const timeFormat = useSettingsStore((s) => s.timeFormat);
+
+  const filteredTasks = useMemo(() => {
+    let result = tasks.filter(task => {
+      const calIds = Object.keys(task.calendarIds);
+      return calIds.some(id => selectedCalendarIds.includes(id));
+    });
+
+    if (!showCompleted) {
+      result = result.filter(task => task.progress !== "completed" && task.progress !== "cancelled");
+    }
+
+    switch (filter) {
+      case "pending":
+        result = result.filter(task => task.progress === "needs-action" || task.progress === "in-process");
+        break;
+      case "completed":
+        result = result.filter(task => task.progress === "completed");
+        break;
+      case "overdue":
+        result = result.filter(task => {
+          if (!task.due || task.progress === "completed" || task.progress === "cancelled") return false;
+          return isPast(parseISO(task.due)) && !isToday(parseISO(task.due));
+        });
+        break;
+    }
+
+    // Sort: overdue first, then by due date (no due date last), then by priority
+    result.sort((a, b) => {
+      // Completed tasks at the bottom
+      if (a.progress === "completed" && b.progress !== "completed") return 1;
+      if (a.progress !== "completed" && b.progress === "completed") return -1;
+
+      // Tasks with due dates before those without
+      if (a.due && !b.due) return -1;
+      if (!a.due && b.due) return 1;
+      if (a.due && b.due) {
+        const dateCompare = new Date(a.due).getTime() - new Date(b.due).getTime();
+        if (dateCompare !== 0) return dateCompare;
+      }
+
+      // Higher priority first (lower number = higher priority, but 0 = no priority goes last)
+      const aPri = a.priority || 10;
+      const bPri = b.priority || 10;
+      return aPri - bPri;
+    });
+
+    return result;
+  }, [tasks, selectedCalendarIds, filter, showCompleted]);
+
+  const handleToggle = useCallback((e: React.MouseEvent, task: CalendarTask) => {
+    e.stopPropagation();
+    onToggleComplete(task);
+  }, [onToggleComplete]);
+
+  if (filteredTasks.length === 0) {
+    return (
+      <div className="flex flex-col items-center justify-center flex-1 text-muted-foreground py-12">
+        <ListTodo className="h-12 w-12 mb-3 opacity-30" />
+        <p className="text-sm">{t("tasks.no_tasks")}</p>
+      </div>
+    );
+  }
+
+  return (
+    <div className="flex-1 overflow-y-auto">
+      <div className="divide-y divide-border">
+        {filteredTasks.map(task => {
+          const cal = calendars.find(c => task.calendarIds[c.id]);
+          const isCompleted = task.progress === "completed";
+          const priorityIcon = getTaskPriorityIcon(task.priority);
+          const dueDateInfo = task.due ? getDueDateLabel(task.due, task.showWithoutTime, t, timeFormat) : null;
+
+          return (
+            <div
+              key={task.id}
+              onClick={() => onSelectTask(task)}
+              className={cn(
+                "flex items-start gap-3 px-4 py-3 cursor-pointer hover:bg-muted/50 transition-colors",
+                selectedTaskId === task.id && "bg-muted",
+              )}
+            >
+              {/* Checkbox */}
+              <button
+                onClick={(e) => handleToggle(e, task)}
+                className={cn(
+                  "mt-0.5 flex-shrink-0 w-5 h-5 rounded-full border-2 flex items-center justify-center transition-colors",
+                  isCompleted
+                    ? "bg-green-500 border-green-500 text-white"
+                    : "border-muted-foreground/40 hover:border-primary"
+                )}
+                aria-label={isCompleted ? t("tasks.mark_incomplete") : t("tasks.mark_complete")}
+              >
+                {isCompleted && <Check className="h-3 w-3" />}
+              </button>
+
+              {/* Content */}
+              <div className="flex-1 min-w-0">
+                <div className="flex items-center gap-1.5">
+                  <span className={cn(
+                    "text-sm font-medium truncate",
+                    isCompleted && "line-through text-muted-foreground"
+                  )}>
+                    {task.title || t("tasks.no_title")}
+                  </span>
+                  {priorityIcon}
+                </div>
+
+                <div className="flex items-center gap-2 mt-0.5">
+                  {dueDateInfo && (
+                    <span className={cn("text-xs flex items-center gap-1", dueDateInfo.className)}>
+                      <CalendarDays className="h-3 w-3" />
+                      {dueDateInfo.label}
+                    </span>
+                  )}
+                  {cal && (
+                    <span className="text-xs text-muted-foreground flex items-center gap-1">
+                      <span className="w-2 h-2 rounded-full flex-shrink-0" style={{ backgroundColor: cal.color || "#3b82f6" }} />
+                      {cal.name}
+                    </span>
+                  )}
+                </div>
+              </div>
+            </div>
+          );
+        })}
+      </div>
+    </div>
+  );
+}

components/contacts/__tests__/contact-list-item.test.tsx

@@ -30,6 +30,7 @@ describe('ContactListItem', () => {
     density: 'regular' as const,
     onClick: vi.fn(),
     onCheckboxClick: vi.fn(),
+    selectedContactIds: new Set<string>(),
   };
 
   it('renders contact name and email', () => {

components/contacts/contact-detail.tsx

@@ -1,12 +1,16 @@
 "use client";
 
+import { useState, useEffect } from "react";
 import { useTranslations } from "next-intl";
-import { Mail, Phone, Building, MapPin, StickyNote, Pencil, Trash2, BookUser, Copy, Send, Globe, Cake, Tag, KeyRound, Link, Users, Briefcase, Heart, Languages, MessageCircle, User, Calendar, UserCircle } from "lucide-react";
+import { Mail, Phone, Building, MapPin, StickyNote, Pencil, Trash2, BookUser, Copy, Send, Globe, Cake, Tag, KeyRound, Link, Users, Briefcase, Heart, Languages, MessageCircle, User, Calendar, UserCircle, ShieldCheck, ShieldAlert, Download } from "lucide-react";
 import { Avatar } from "@/components/ui/avatar";
 import { Button } from "@/components/ui/button";
 import { cn } from "@/lib/utils";
-import type { ContactCard } from "@/lib/jmap/types";
+import type { ContactCard, AnniversaryDate, PartialDate } from "@/lib/jmap/types";
 import { getContactDisplayName, getContactPrimaryEmail } from "@/stores/contact-store";
+import { useSmimeStore } from "@/stores/smime-store";
+import { parseCertificatePemOrDer, extractCertificateInfo } from "@/lib/smime/certificate-utils";
+import type { CertificateInfo } from "@/lib/smime/types";
 import { toast } from "@/stores/toast-store";
 
 interface ContactDetailProps {
@@ -22,12 +26,23 @@ function formatPhoneFeatures(features?: Record<string, boolean>): string {
   return Object.keys(features).filter(k => features[k]).join(", ");
 }
 
-function formatDate(dateInput: string | Record<string, unknown>): string {
+function formatDate(dateInput: AnniversaryDate): string {
   // Handle RFC 9553 PartialDate objects: { year?, month?, day?, calendarScale? }
+  // Handle RFC 9553 Timestamp objects: { "@type": "Timestamp", utc: "..." }
   if (typeof dateInput === 'object' && dateInput !== null) {
-    const year = dateInput.year as number | undefined;
+    if (dateInput['@type'] === 'Timestamp' && typeof dateInput.utc === 'string') {
-    const month = dateInput.month as number | undefined;
+      try {
-    const day = dateInput.day as number | undefined;
+        const d = new Date(dateInput.utc as string);
+        if (!isNaN(d.getTime())) {
+          return d.toLocaleDateString(undefined, { year: "numeric", month: "long", day: "numeric" });
+        }
+      } catch { /* fallback */ }
+      return String(dateInput.utc);
+    }
+    const pd = dateInput as PartialDate;
+    const year = pd.year;
+    const month = pd.month;
+    const day = pd.day;
     const monthNames = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"];
     const parts: string[] = [];
     if (month && monthNames[month - 1]) parts.push(monthNames[month - 1]);
@@ -56,6 +71,50 @@ function formatDate(dateInput: string | Record<string, unknown>): string {
 
 export function ContactDetail({ contact, onEdit, onDelete, isMobile, className }: ContactDetailProps) {
   const t = useTranslations("contacts");
+  const smimeStore = useSmimeStore();
+  const [parsedCerts, setParsedCerts] = useState<Map<number, CertificateInfo>>(new Map());
+
+  const cryptoKeys = contact?.cryptoKeys ? Object.values(contact.cryptoKeys) : [];
+
+  useEffect(() => {
+    if (!contact) return;
+    let cancelled = false;
+    const parseCerts = async () => {
+      const results = new Map<number, CertificateInfo>();
+      for (let i = 0; i < cryptoKeys.length; i++) {
+        const key = cryptoKeys[i];
+        if (typeof key.uri !== 'string') continue;
+        try {
+          let derBytes: ArrayBuffer | string | null = null;
+          if (key.uri.startsWith('data:')) {
+            // data URI — extract base64 content
+            const commaIdx = key.uri.indexOf(',');
+            if (commaIdx === -1) continue;
+            const b64 = key.uri.substring(commaIdx + 1);
+            const binary = atob(b64);
+            const bytes = new Uint8Array(binary.length);
+            for (let j = 0; j < binary.length; j++) bytes[j] = binary.charCodeAt(j);
+            derBytes = bytes.buffer;
+          } else if (key.uri.startsWith('-----BEGIN')) {
+            // PEM-encoded certificate inline
+            derBytes = key.uri;
+          }
+          if (!derBytes) continue;
+          const cert = parseCertificatePemOrDer(derBytes);
+          const der = typeof derBytes === 'string' ? cert.toSchema(true).toBER(false) : derBytes;
+          const info = await extractCertificateInfo(cert, der);
+          if (!cancelled) results.set(i, info);
+        } catch { /* skip unparseable keys */ }
+      }
+      if (!cancelled) setParsedCerts(results);
+    };
+    if (cryptoKeys.length > 0) {
+      parseCerts();
+    } else {
+      setParsedCerts(new Map());
+    }
+    return () => { cancelled = true; };
+  }, [contact?.id]); // eslint-disable-line react-hooks/exhaustive-deps
 
   if (!contact) {
     return (
@@ -79,7 +138,31 @@ export function ContactDetail({ contact, onEdit, onDelete, isMobile, className }
   const onlineServices = contact.onlineServices ? Object.values(contact.onlineServices) : [];
   const anniversaries = contact.anniversaries ? Object.values(contact.anniversaries) : [];
   const keywords = contact.keywords ? Object.keys(contact.keywords).filter(k => contact.keywords![k]) : [];
-  const cryptoKeys = contact.cryptoKeys ? Object.values(contact.cryptoKeys) : [];
+
+  const handleImportContactCert = async (keyIndex: number) => {
+    const key = cryptoKeys[keyIndex];
+    if (!key?.uri || typeof key.uri !== 'string') return;
+    try {
+      let derBytes: ArrayBuffer | string;
+      if (key.uri.startsWith('data:')) {
+        const commaIdx = key.uri.indexOf(',');
+        if (commaIdx === -1) return;
+        const b64 = key.uri.substring(commaIdx + 1);
+        const binary = atob(b64);
+        const bytes = new Uint8Array(binary.length);
+        for (let j = 0; j < binary.length; j++) bytes[j] = binary.charCodeAt(j);
+        derBytes = bytes.buffer;
+      } else if (key.uri.startsWith('-----BEGIN')) {
+        derBytes = key.uri;
+      } else {
+        return;
+      }
+      await smimeStore.importPublicCert(derBytes, 'contact', contact.id);
+      toast.success(t("detail.cert_imported"));
+    } catch (err) {
+      toast.error(err instanceof Error ? err.message : t("detail.cert_import_failed"));
+    }
+  };
   const relatedTo = contact.relatedTo ? Object.entries(contact.relatedTo) : [];
   const preferredLanguages = contact.preferredLanguages ? Object.values(contact.preferredLanguages) : [];
   const personalInfo = contact.personalInfo ? Object.values(contact.personalInfo) : [];
@@ -210,9 +293,11 @@ export function ContactDetail({ contact, onEdit, onDelete, isMobile, className }
                   {addresses.map((a, i) => (
                     <div key={i} className="text-sm space-y-0.5 rounded-md border border-border/60 bg-muted/30 p-3">
                       <div>
-                        {a.fullAddress
+                        {a.full || a.fullAddress
-                          ? a.fullAddress
+                          ? (a.full || a.fullAddress)
-                          : [a.street, a.locality, a.region, a.postcode, a.country].filter(Boolean).join(", ")}
+                          : a.components && a.components.length > 0
+                            ? a.components.filter(c => c.kind !== 'separator').map(c => c.value).filter(Boolean).join(", ")
+                            : [a.street, a.locality, a.region, a.postcode, a.country].filter(Boolean).join(", ")}
                         {a.contexts && <ContextBadge contexts={a.contexts} />}
                       </div>
                       {a.timeZone && (
@@ -279,13 +364,16 @@ export function ContactDetail({ contact, onEdit, onDelete, isMobile, className }
             </Section>
           )}
 
-          {contact.gender && (contact.gender.sex || contact.gender.identity) && (
+          {contact.speakToAs && (contact.speakToAs.grammaticalGender || contact.speakToAs.pronouns) && (
             <Section icon={UserCircle} title={t("detail.gender")} category="personal">
               <div className="text-sm">
-                {contact.gender.sex && <span>{t(`detail.gender_${contact.gender.sex.toUpperCase()}`, { defaultValue: contact.gender.sex })}</span>}
+                {contact.speakToAs.grammaticalGender && <span>{t(`detail.gender_${contact.speakToAs.grammaticalGender}`, { defaultValue: contact.speakToAs.grammaticalGender })}</span>}
-                {contact.gender.identity && (
+                {contact.speakToAs.pronouns && (() => {
-                  <span className="text-muted-foreground">{contact.gender.sex ? " — " : ""}{contact.gender.identity}</span>
+                  const firstPronoun = Object.values(contact.speakToAs!.pronouns!)[0]?.pronouns;
-                )}
+                  return firstPronoun ? (
+                    <span className="text-muted-foreground">{contact.speakToAs!.grammaticalGender ? " — " : ""}{firstPronoun}</span>
+                  ) : null;
+                })()}
               </div>
             </Section>
           )}
@@ -331,17 +419,63 @@ export function ContactDetail({ contact, onEdit, onDelete, isMobile, className }
 
           {cryptoKeys.length > 0 && (
             <Section icon={KeyRound} title={t("detail.crypto_keys")} category="digital">
-              {cryptoKeys.map((key, i) => (
+              {cryptoKeys.map((key, i) => {
-                <div key={i} className="text-sm break-all">
+                const certInfo = parsedCerts.get(i);
-                  {typeof key.uri === 'string' && key.uri.startsWith("http") ? (
+                const isExpired = certInfo ? new Date(certInfo.notAfter) < new Date() : false;
-                    <a href={key.uri} target="_blank" rel="noopener noreferrer" className="text-primary hover:underline">
+                const alreadyImported = certInfo?.emailAddresses?.[0]
-                      {key.uri}
+                  ? !!smimeStore.getPublicCertForEmail(certInfo.emailAddresses[0])
-                    </a>
+                  : false;
-                  ) : (
+
-                    <span className="text-muted-foreground">{typeof key.uri === 'string' ? `${key.uri.substring(0, 80)}${key.uri.length > 80 ? "…" : ""}` : String(key.uri ?? '')}</span>
+                return (
-                  )}
+                  <div key={i} className="p-3 rounded-lg border border-border space-y-1">
-                </div>
+                    {certInfo ? (
-              ))}
+                      <>
+                        <div className="flex items-center gap-2">
+                          {isExpired ? (
+                            <ShieldAlert className="w-4 h-4 text-destructive flex-shrink-0" />
+                          ) : (
+                            <ShieldCheck className="w-4 h-4 text-primary flex-shrink-0" />
+                          )}
+                          <span className="text-sm font-medium truncate">{certInfo.subject}</span>
+                        </div>
+                        <div className="text-xs text-muted-foreground space-y-0.5 pl-6">
+                          <p>{t("detail.cert_issuer")}: {certInfo.issuer}</p>
+                          <p>
+                            {t("detail.cert_expires")}: {new Date(certInfo.notAfter).toLocaleDateString()}
+                            {isExpired && <span className="text-destructive ml-1">({t("detail.cert_expired")})</span>}
+                          </p>
+                          <p>{t("detail.cert_fingerprint")}: {certInfo.fingerprint.substring(0, 20)}...</p>
+                          {certInfo.algorithm && <p>{t("detail.cert_algorithm")}: {certInfo.algorithm}</p>}
+                        </div>
+                        {!alreadyImported && (
+                          <Button
+                            variant="ghost"
+                            size="sm"
+                            className="ml-4 mt-1"
+                            onClick={() => handleImportContactCert(i)}
+                          >
+                            <Download className="w-3 h-3 mr-1" />
+                            {t("detail.import_to_smime")}
+                          </Button>
+                        )}
+                        {alreadyImported && (
+                          <p className="text-xs text-green-600 pl-6 mt-1">{t("detail.cert_already_imported")}</p>
+                        )}
+                      </>
+                    ) : (
+                      <div className="text-sm break-all">
+                        {typeof key.uri === 'string' && key.uri.startsWith("http") ? (
+                          <a href={key.uri} target="_blank" rel="noopener noreferrer" className="text-primary hover:underline">
+                            {key.uri}
+                          </a>
+                        ) : (
+                          <span className="text-muted-foreground">{typeof key.uri === 'string' ? `${key.uri.substring(0, 80)}${key.uri.length > 80 ? "…" : ""}` : String(key.uri ?? '')}</span>
+                        )}
+                      </div>
+                    )}
+                  </div>
+                );
+              })}
             </Section>
           )}
 

components/contacts/contact-form.tsx

@@ -1,12 +1,12 @@
 "use client";
 
-import { useState } from "react";
+import { useState, useMemo } from "react";
 import { useTranslations } from "next-intl";
-import { X, Plus, ChevronDown, ChevronRight, User, Building, MapPin, Globe, Cake, Heart, Tag, StickyNote, Mail, Phone, Calendar, UserCircle } from "lucide-react";
+import { X, Plus, ChevronDown, ChevronRight, User, Building, MapPin, Globe, Cake, Heart, Tag, StickyNote, Mail, Phone, Calendar, UserCircle, Book } from "lucide-react";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { cn } from "@/lib/utils";
-import type { ContactCard, ContactOnlineService, ContactAnniversary, ContactPersonalInfo } from "@/lib/jmap/types";
+import type { ContactCard, ContactOnlineService, ContactAnniversary, ContactPersonalInfo, AddressBook, AnniversaryDate, PartialDate, ContactAddress } from "@/lib/jmap/types";
 
 interface EmailEntry {
   address: string;
@@ -47,6 +47,7 @@ interface AddressEntry {
 
 interface ContactFormProps {
   contact?: ContactCard | null;
+  addressBooks?: AddressBook[];
   onSave: (data: Partial<ContactCard>) => Promise<void>;
   onCancel: () => void;
 }
@@ -122,12 +123,73 @@ function Select({ value, onChange, children, className }: {
   );
 }
 
-export function ContactForm({ contact, onSave, onCancel }: ContactFormProps) {
+export function ContactForm({ contact, addressBooks, onSave, onCancel }: ContactFormProps) {
   const t = useTranslations("contacts.form");
   const isEditing = !!contact;
 
   const findComponent = (kind: string) => contact?.name?.components?.find(c => c.kind === kind)?.value || "";
 
+  // Convert RFC 9553 AnniversaryDate to ISO date string for HTML date input
+  function anniversaryDateToString(date: AnniversaryDate): string {
+    if (typeof date === 'string') return date;
+    if (date && typeof date === 'object') {
+      if ('@type' in date && date['@type'] === 'Timestamp' && 'utc' in date) {
+        return (date as { utc: string }).utc.split('T')[0];
+      }
+      const pd = date as PartialDate;
+      if (pd.year && pd.month && pd.day) {
+        return `${String(pd.year).padStart(4, '0')}-${String(pd.month).padStart(2, '0')}-${String(pd.day).padStart(2, '0')}`;
+      }
+      if (pd.month && pd.day) {
+        return `--${String(pd.month).padStart(2, '0')}-${String(pd.day).padStart(2, '0')}`;
+      }
+      if (pd.year && pd.month) {
+        return `${String(pd.year).padStart(4, '0')}-${String(pd.month).padStart(2, '0')}`;
+      }
+      if (pd.year) return String(pd.year);
+    }
+    return String(date);
+  }
+
+  // Convert ISO date string back to RFC 9553 PartialDate for the server
+  function stringToPartialDate(str: string): PartialDate {
+    if (str.startsWith('--')) {
+      const parts = str.substring(2).split('-');
+      const pd: PartialDate = { month: parseInt(parts[0], 10) };
+      if (parts[1]) pd.day = parseInt(parts[1], 10);
+      return pd;
+    }
+    const parts = str.split('-');
+    const pd: PartialDate = {};
+    if (parts[0]) pd.year = parseInt(parts[0], 10);
+    if (parts[1]) pd.month = parseInt(parts[1], 10);
+    if (parts[2]) pd.day = parseInt(parts[2], 10);
+    return pd;
+  }
+
+  // Extract flat address fields from RFC 9553 components format
+  function addressToFlat(a: ContactAddress): AddressEntry {
+    if (a.components && a.components.length > 0) {
+      const findComp = (kind: string) => a.components!.filter(c => c.kind === kind).map(c => c.value).join(' ');
+      return {
+        street: findComp('name') || findComp('number') ? [findComp('number'), findComp('name')].filter(Boolean).join(' ') : '',
+        locality: findComp('locality'),
+        region: findComp('region'),
+        postcode: findComp('postcode'),
+        country: findComp('country'),
+        context: a.contexts?.work ? 'work' : a.contexts?.private ? 'private' : '',
+      };
+    }
+    return {
+      street: a.street || '',
+      locality: a.locality || '',
+      region: a.region || '',
+      postcode: a.postcode || '',
+      country: a.country || '',
+      context: a.contexts?.work ? 'work' : a.contexts?.private ? 'private' : '',
+    };
+  }
+
   const [prefix, setPrefix] = useState(findComponent("prefix"));
   const [givenName, setGivenName] = useState(findComponent("given"));
   const [additionalName, setAdditionalName] = useState(findComponent("additional"));
@@ -183,14 +245,7 @@ export function ContactForm({ contact, onSave, onCancel }: ContactFormProps) {
 
   const [addresses, setAddresses] = useState<AddressEntry[]>(() => {
     if (contact?.addresses) {
-      return Object.values(contact.addresses).map(a => ({
+      return Object.values(contact.addresses).map(a => addressToFlat(a));
-        street: a.street || "",
-        locality: a.locality || "",
-        region: a.region || "",
-        postcode: a.postcode || "",
-        country: a.country || "",
-        context: a.contexts?.work ? "work" : a.contexts?.private ? "private" : "",
-      }));
     }
     return [];
   });
@@ -209,7 +264,7 @@ export function ContactForm({ contact, onSave, onCancel }: ContactFormProps) {
   const [anniversaries, setAnniversaries] = useState<AnniversaryEntry[]>(() => {
     if (contact?.anniversaries) {
       return Object.values(contact.anniversaries).map(a => ({
-        date: a.date,
+        date: anniversaryDateToString(a.date),
         kind: a.kind,
       }));
     }
@@ -235,12 +290,31 @@ export function ContactForm({ contact, onSave, onCancel }: ContactFormProps) {
     contact?.notes ? Object.values(contact.notes)[0]?.note || "" : ""
   );
 
-  const [genderSex, setGenderSex] = useState(contact?.gender?.sex || "");
+  const [genderSex, setGenderSex] = useState(contact?.speakToAs?.grammaticalGender || "");
-  const [genderIdentity, setGenderIdentity] = useState(contact?.gender?.identity || "");
+  const [genderIdentity, setGenderIdentity] = useState(
+    contact?.speakToAs?.pronouns ? Object.values(contact.speakToAs.pronouns)[0]?.pronouns || "" : ""
+  );
   const [calendarUri, setCalendarUri] = useState(contact?.calendarUri || "");
   const [schedulingUri, setSchedulingUri] = useState(contact?.schedulingUri || "");
   const [freeBusyUri, setFreeBusyUri] = useState(contact?.freeBusyUri || "");
 
+  // Address book selection
+  const currentBookId = useMemo(() => {
+    if (contact?.addressBookIds) {
+      const ids = Object.keys(contact.addressBookIds).filter(k => contact.addressBookIds[k]);
+      if (ids.length > 0) {
+        // For shared contacts, the addressBookIds uses the original (non-namespaced) id
+        // but we need the namespaced id to match addressBooks entries
+        if (contact.isShared && contact.accountId) {
+          return `${contact.accountId}:${ids[0]}`;
+        }
+        return ids[0];
+      }
+    }
+    return "";
+  }, [contact]);
+  const [selectedBookId, setSelectedBookId] = useState(currentBookId);
+
   const [isSaving, setIsSaving] = useState(false);
   const [error, setError] = useState<string | null>(null);
   const [emailErrors, setEmailErrors] = useState<Record<number, string>>({});
@@ -316,12 +390,13 @@ export function ContactForm({ contact, onSave, onCancel }: ContactFormProps) {
 
     const addressesMap: Record<string, ContactCard["addresses"] extends Record<string, infer V> ? V : never> = {};
     addresses.filter(a => a.street.trim() || a.locality.trim() || a.country.trim()).forEach((a, i) => {
-      const obj: Record<string, unknown> = {};
+      const components: Array<{ kind: string; value: string }> = [];
-      if (a.street.trim()) obj.street = a.street.trim();
+      if (a.street.trim()) components.push({ kind: "name", value: a.street.trim() });
-      if (a.locality.trim()) obj.locality = a.locality.trim();
+      if (a.locality.trim()) components.push({ kind: "locality", value: a.locality.trim() });
-      if (a.region.trim()) obj.region = a.region.trim();
+      if (a.region.trim()) components.push({ kind: "region", value: a.region.trim() });
-      if (a.postcode.trim()) obj.postcode = a.postcode.trim();
+      if (a.postcode.trim()) components.push({ kind: "postcode", value: a.postcode.trim() });
-      if (a.country.trim()) obj.country = a.country.trim();
+      if (a.country.trim()) components.push({ kind: "country", value: a.country.trim() });
+      const obj: Record<string, unknown> = { components, isOrdered: true, defaultSeparator: ", " };
       if (a.context) obj.contexts = { [a.context]: true };
       // @ts-expect-error - dynamic build
       addressesMap[`a${i}`] = obj;
@@ -337,7 +412,7 @@ export function ContactForm({ contact, onSave, onCancel }: ContactFormProps) {
 
     const anniversariesMap: Record<string, ContactAnniversary> = {};
     anniversaries.filter(a => a.date.trim()).forEach((a, i) => {
-      anniversariesMap[`an${i}`] = { date: a.date.trim(), kind: a.kind };
+      anniversariesMap[`an${i}`] = { date: stringToPartialDate(a.date.trim()), kind: a.kind };
     });
 
     const personalInfoMap: Record<string, ContactPersonalInfo> = {};
@@ -371,12 +446,16 @@ export function ContactForm({ contact, onSave, onCancel }: ContactFormProps) {
       notes: note.trim()
         ? { n0: { note: note.trim() } }
         : undefined,
-      gender: (genderSex.trim() || genderIdentity.trim())
+      speakToAs: (genderSex.trim() || genderIdentity.trim())
-        ? { sex: genderSex.trim() || undefined, identity: genderIdentity.trim() || undefined }
+        ? {
+            grammaticalGender: genderSex.trim() || undefined,
+            pronouns: genderIdentity.trim() ? { p0: { pronouns: genderIdentity.trim() } } : undefined,
+          }
         : undefined,
       calendarUri: calendarUri.trim() || undefined,
       schedulingUri: schedulingUri.trim() || undefined,
       freeBusyUri: freeBusyUri.trim() || undefined,
+      ...(selectedBookId ? { addressBookIds: { [selectedBookId]: true } } : {}),
     };
 
     setIsSaving(true);
@@ -410,6 +489,26 @@ export function ContactForm({ contact, onSave, onCancel }: ContactFormProps) {
 
           <div className="grid grid-cols-1 md:grid-cols-2 xl:grid-cols-3 gap-4">
 
+          {/* Address Book Selector */}
+          {addressBooks && addressBooks.length > 1 && (
+            <div className="md:col-span-2 xl:col-span-3">
+              <FormSection icon={Book} title={t("section_address_book") || "Directory"} category="contact">
+                <select
+                  value={selectedBookId}
+                  onChange={(e) => setSelectedBookId(e.target.value)}
+                  className="w-full px-3 py-2 rounded-md border border-border bg-background text-sm focus:outline-none focus:ring-2 focus:ring-primary/50"
+                >
+                  <option value="">{t("select_address_book") || "Select a directory..."}</option>
+                  {addressBooks.map((book) => (
+                    <option key={book.id} value={book.id}>
+                      {book.accountName ? `${book.name} (${book.accountName})` : book.name}
+                    </option>
+                  ))}
+                </select>
+              </FormSection>
+            </div>
+          )}
+
           {/* Name & Identity — full width */}
           <div className="md:col-span-2 xl:col-span-3">
           <FormSection icon={User} title={t("section_identity")} category="contact">
@@ -737,11 +836,11 @@ export function ContactForm({ contact, onSave, onCancel }: ContactFormProps) {
                 <label className="text-xs text-muted-foreground mb-1 block">{t("gender_sex")}</label>
                 <Select value={genderSex} onChange={(e) => setGenderSex(e.target.value)} className="w-full">
                   <option value="">—</option>
-                  <option value="M">{t("gender_male")}</option>
+                  <option value="masculine">{t("gender_male")}</option>
-                  <option value="F">{t("gender_female")}</option>
+                  <option value="feminine">{t("gender_female")}</option>
-                  <option value="O">{t("gender_other")}</option>
+                  <option value="other">{t("gender_other")}</option>
-                  <option value="N">{t("gender_none")}</option>
+                  <option value="none">{t("gender_none")}</option>
-                  <option value="U">{t("gender_unknown")}</option>
+                  <option value="unknown">{t("gender_unknown")}</option>
                 </Select>
               </div>
               <div>

components/contacts/contact-list-item.tsx

@@ -1,5 +1,6 @@
 "use client";
 
+import { useCallback, type DragEvent } from "react";
 import { Avatar } from "@/components/ui/avatar";
 import { cn } from "@/lib/utils";
 import type { ContactCard } from "@/lib/jmap/types";
@@ -13,19 +14,47 @@ interface ContactListItemProps {
   isChecked: boolean;
   hasSelection: boolean;
   density: Density;
+  selectedContactIds: Set<string>;
   onClick: (e: React.MouseEvent) => void;
   onCheckboxClick: (e: React.MouseEvent) => void;
 }
 
-export function ContactListItem({ contact, isSelected, isChecked, hasSelection, density, onClick, onCheckboxClick }: ContactListItemProps) {
+export function ContactListItem({ contact, isSelected, isChecked, hasSelection, density, selectedContactIds, onClick, onCheckboxClick }: ContactListItemProps) {
   const name = getContactDisplayName(contact);
   const email = getContactPrimaryEmail(contact);
   const org = contact.organizations
     ? Object.values(contact.organizations)[0]?.name
     : undefined;
 
+  const handleDragStart = useCallback((e: DragEvent<HTMLDivElement>) => {
+    // Drag all selected contacts if this one is selected, otherwise just this one
+    const ids = selectedContactIds.has(contact.id)
+      ? Array.from(selectedContactIds)
+      : [contact.id];
+
+    e.dataTransfer.effectAllowed = "move";
+    e.dataTransfer.setData("application/x-contact-ids", JSON.stringify(ids));
+    e.dataTransfer.setData("text/plain", name || email || contact.id);
+
+    // Custom drag preview
+    const preview = document.createElement("div");
+    preview.style.cssText = `
+      position: fixed; top: -9999px; left: 0;
+      padding: 8px 16px; background-color: var(--color-primary, #3b82f6);
+      color: var(--color-primary-foreground, #ffffff); border-radius: 8px;
+      box-shadow: 0 4px 12px rgba(0,0,0,0.15); font-size: 14px; font-weight: 500;
+      z-index: 9999; white-space: nowrap; pointer-events: none;
+    `;
+    preview.textContent = ids.length === 1 ? (name || "1 contact") : `${ids.length} contacts`;
+    document.body.appendChild(preview);
+    e.dataTransfer.setDragImage(preview, 0, 0);
+    requestAnimationFrame(() => preview.remove());
+  }, [contact.id, name, email, selectedContactIds]);
+
   return (
     <div
+      draggable
+      onDragStart={handleDragStart}
       onClick={onClick}
       className={cn(
         "w-full flex items-center cursor-pointer select-none transition-all duration-200 border-b border-border",

components/contacts/contact-list.tsx

@@ -193,6 +193,7 @@ export function ContactList({
                 isChecked={selectedContactIds.has(contact.id)}
                 hasSelection={hasSelection}
                 density={density}
+                selectedContactIds={selectedContactIds}
                 onClick={(e) => {
                   if (e.ctrlKey || e.metaKey) {
                     e.preventDefault();

components/contacts/contacts-sidebar.tsx

@@ -1,35 +1,93 @@
 "use client";
 
-import { useMemo } from "react";
+import { useMemo, useState, useCallback, useEffect, useRef, type DragEvent } from "react";
 import { useTranslations } from "next-intl";
-import { BookUser, Users, Plus, UserPlus } from "lucide-react";
+import { BookUser, Users, Plus, Share2, Book, ChevronRight, ChevronDown, UserPlus, UsersRound, Upload, Tag, Pencil, Trash2 } from "lucide-react";
 import { Button } from "@/components/ui/button";
+import { ContextMenu, ContextMenuItem, ContextMenuSeparator } from "@/components/ui/context-menu";
+import { useContextMenu } from "@/hooks/use-context-menu";
 import { cn } from "@/lib/utils";
-import type { ContactCard } from "@/lib/jmap/types";
+import type { ContactCard, AddressBook } from "@/lib/jmap/types";
 import { getContactDisplayName } from "@/stores/contact-store";
 
-export type ContactCategory = "all" | { groupId: string };
+export type ContactCategory = "all" | { groupId: string } | { addressBookId: string } | { keyword: string };
 
 interface ContactsSidebarProps {
   groups: ContactCard[];
   individuals: ContactCard[];
+  addressBooks: AddressBook[];
   activeCategory: ContactCategory;
   onSelectCategory: (category: ContactCategory) => void;
   onCreateGroup: () => void;
   onCreateContact: () => void;
+  onImport?: () => void;
+  onEditGroup?: (groupId: string) => void;
+  onDeleteGroup?: (groupId: string) => void;
+  onDropContacts?: (contactIds: string[], addressBook: AddressBook) => void;
   className?: string;
 }
 
+const COLLAPSED_KEY = "contacts-sidebar-collapsed";
+
+function loadCollapsed(): Record<string, boolean> {
+  try {
+    const v = localStorage.getItem(COLLAPSED_KEY);
+    return v ? JSON.parse(v) : {};
+  } catch {
+    return {};
+  }
+}
+
+function saveCollapsed(state: Record<string, boolean>) {
+  try {
+    localStorage.setItem(COLLAPSED_KEY, JSON.stringify(state));
+  } catch { /* ignore */ }
+}
+
 export function ContactsSidebar({
   groups,
   individuals,
+  addressBooks,
   activeCategory,
   onSelectCategory,
   onCreateGroup,
   onCreateContact,
+  onImport,
+  onEditGroup,
+  onDeleteGroup,
+  onDropContacts,
   className,
 }: ContactsSidebarProps) {
   const t = useTranslations("contacts");
+  const { contextMenu: groupContextMenu, openContextMenu: openGroupContextMenu, closeContextMenu: closeGroupContextMenu, menuRef: groupMenuRef } = useContextMenu<ContactCard>();
+
+  const [collapsed, setCollapsed] = useState<Record<string, boolean>>(loadCollapsed);
+  const [showMenu, setShowMenu] = useState(false);
+  const menuRef = useRef<HTMLDivElement>(null);
+  const menuBtnRef = useRef<HTMLButtonElement>(null);
+
+  const toggleSection = useCallback((key: string) => {
+    setCollapsed(prev => {
+      const next = { ...prev, [key]: !prev[key] };
+      saveCollapsed(next);
+      return next;
+    });
+  }, []);
+
+  // Close dropdown on outside click
+  useEffect(() => {
+    if (!showMenu) return;
+    const handler = (e: MouseEvent) => {
+      if (
+        menuRef.current && !menuRef.current.contains(e.target as Node) &&
+        menuBtnRef.current && !menuBtnRef.current.contains(e.target as Node)
+      ) {
+        setShowMenu(false);
+      }
+    };
+    document.addEventListener("mousedown", handler);
+    return () => document.removeEventListener("mousedown", handler);
+  }, [showMenu]);
 
   const sortedGroups = useMemo(() => {
     return [...groups].sort((a, b) =>
@@ -39,17 +97,126 @@ export function ContactsSidebar({
 
   const isAllActive = activeCategory === "all";
 
+  // Group address books: personal vs shared accounts
+  const personalBooks = useMemo(() =>
+    addressBooks.filter(b => !b.isShared),
+  [addressBooks]);
+
+  const sharedBookGroups = useMemo(() => {
+    const map = new Map<string, { accountId: string; accountName: string; books: AddressBook[] }>();
+    for (const book of addressBooks) {
+      if (!book.isShared || !book.accountId) continue;
+      const existing = map.get(book.accountId);
+      if (existing) {
+        existing.books.push(book);
+      } else {
+        map.set(book.accountId, {
+          accountId: book.accountId,
+          accountName: book.accountName || book.accountId,
+          books: [book],
+        });
+      }
+    }
+    return Array.from(map.values());
+  }, [addressBooks]);
+
+  // Count contacts per address book
+  const contactCountByBook = useMemo(() => {
+    const counts: Record<string, number> = {};
+    for (const contact of individuals) {
+      if (!contact.addressBookIds) continue;
+      for (const bookId of Object.keys(contact.addressBookIds)) {
+        if (!contact.addressBookIds[bookId]) continue;
+        counts[bookId] = (counts[bookId] || 0) + 1;
+      }
+    }
+    return counts;
+  }, [individuals]);
+
+  // Auto-collect keywords from all contacts
+  const allKeywords = useMemo(() => {
+    const counts: Record<string, number> = {};
+    for (const contact of individuals) {
+      if (!contact.keywords) continue;
+      for (const [kw, active] of Object.entries(contact.keywords)) {
+        if (!active) continue;
+        counts[kw] = (counts[kw] || 0) + 1;
+      }
+    }
+    return Object.entries(counts).sort(([a], [b]) => a.localeCompare(b));
+  }, [individuals]);
+
+  // Resolve actual group member counts against living contacts
+  const memberCountByGroup = useMemo(() => {
+    const counts: Record<string, number> = {};
+    for (const group of groups) {
+      if (!group.members) {
+        counts[group.id] = 0;
+        continue;
+      }
+      const memberKeys = Object.keys(group.members).filter(k => group.members![k]);
+      const normalizedKeys = memberKeys.map(k => k.startsWith('urn:uuid:') ? k.slice(9) : k);
+      counts[group.id] = individuals.filter(c => {
+        if (memberKeys.includes(c.id) || normalizedKeys.includes(c.id)) return true;
+        if (c.uid) {
+          const bareUid = c.uid.startsWith('urn:uuid:') ? c.uid.slice(9) : c.uid;
+          return memberKeys.includes(c.uid) || normalizedKeys.includes(bareUid);
+        }
+        return false;
+      }).length;
+    }
+    return counts;
+  }, [groups, individuals]);
+
   return (
     <div className={cn("flex flex-col h-full bg-secondary", className)}>
       {/* Header */}
       <div className="px-3 border-b border-border flex items-center justify-between" style={{ paddingBlock: 'var(--density-header-py)' }}>
         <span className="text-sm font-semibold truncate">{t("title")}</span>
-        <Button size="icon" variant="ghost" onClick={onCreateContact} className="h-7 w-7 flex-shrink-0">
+        <div className="relative flex-shrink-0">
-          <UserPlus className="w-4 h-4" />
+          <Button
-        </Button>
+            ref={menuBtnRef}
+            size="icon"
+            variant="ghost"
+            onClick={() => setShowMenu(v => !v)}
+            className="h-7 w-7"
+          >
+            <Plus className="w-4 h-4" />
+          </Button>
+          {showMenu && (
+            <div
+              ref={menuRef}
+              className="absolute right-0 top-full mt-1 w-44 rounded-md border border-border bg-background text-foreground shadow-md z-50 py-1"
+            >
+              <button
+                className="w-full flex items-center gap-2 px-3 py-1.5 text-sm hover:bg-accent transition-colors text-left"
+                onClick={() => { setShowMenu(false); onCreateContact(); }}
+              >
+                <UserPlus className="w-4 h-4" />
+                {t("create_new")}
+              </button>
+              <button
+                className="w-full flex items-center gap-2 px-3 py-1.5 text-sm hover:bg-accent transition-colors text-left"
+                onClick={() => { setShowMenu(false); onCreateGroup(); }}
+              >
+                <UsersRound className="w-4 h-4" />
+                {t("groups.create")}
+              </button>
+              {onImport && (
+                <button
+                  className="w-full flex items-center gap-2 px-3 py-1.5 text-sm hover:bg-accent transition-colors text-left"
+                  onClick={() => { setShowMenu(false); onImport(); }}
+                >
+                  <Upload className="w-4 h-4" />
+                  {t("import.title")}
+                </button>
+              )}
+            </div>
+          )}
+        </div>
       </div>
 
-      {/* Categories */}
+      {/* Navigation */}
       <div className="flex-1 overflow-y-auto py-1">
         {/* All contacts */}
         <button
@@ -69,30 +236,63 @@ export function ContactsSidebar({
           </span>
         </button>
 
-        {/* Groups section */}
+        {/* My Address Books */}
-        {(sortedGroups.length > 0) && (
+        {personalBooks.length > 0 && (
           <div className="mt-2">
-            <div className="flex items-center justify-between px-3 py-1">
+            <button
+              onClick={() => toggleSection("addressBooks")}
+              className="flex items-center gap-1 px-3 py-1 w-full text-left group"
+            >
+              {collapsed.addressBooks ? (
+                <ChevronRight className="w-3 h-3 text-muted-foreground" />
+              ) : (
+                <ChevronDown className="w-3 h-3 text-muted-foreground" />
+              )}
+              <span className="text-xs font-medium text-muted-foreground uppercase tracking-wider">
+                {t("address_books.title")}
+              </span>
+            </button>
+            {!collapsed.addressBooks && personalBooks.map((book) => (
+              <AddressBookItem
+                key={book.id}
+                book={book}
+                isActive={typeof activeCategory === "object" && "addressBookId" in activeCategory && activeCategory.addressBookId === book.id}
+                contactCount={contactCountByBook[book.id] || 0}
+                onSelect={() => onSelectCategory({ addressBookId: book.id })}
+                onDropContacts={onDropContacts}
+              />
+            ))}
+          </div>
+        )}
+
+        {/* Groups section */}
+        {sortedGroups.length > 0 && (
+          <div className="mt-2">
+            <button
+              onClick={() => toggleSection("groups")}
+              className="flex items-center gap-1 px-3 py-1 w-full text-left group"
+            >
+              {collapsed.groups ? (
+                <ChevronRight className="w-3 h-3 text-muted-foreground" />
+              ) : (
+                <ChevronDown className="w-3 h-3 text-muted-foreground" />
+              )}
               <span className="text-xs font-medium text-muted-foreground uppercase tracking-wider">
                 {t("tabs.groups")}
               </span>
-              <Button size="icon" variant="ghost" onClick={onCreateGroup} className="h-5 w-5">
+            </button>
-                <Plus className="w-3 h-3" />
-              </Button>
-            </div>
 
-            {sortedGroups.map((group) => {
+            {!collapsed.groups && sortedGroups.map((group) => {
-              const isActive = typeof activeCategory === "object" && activeCategory.groupId === group.id;
+              const isActive = typeof activeCategory === "object" && "groupId" in activeCategory && activeCategory.groupId === group.id;
-              const memberCount = group.members
+              const memberCount = memberCountByGroup[group.id] || 0;
-                ? Object.values(group.members).filter(Boolean).length
-                : 0;
 
               return (
                 <button
                   key={group.id}
                   onClick={() => onSelectCategory({ groupId: group.id })}
+                  onContextMenu={(e) => openGroupContextMenu(e, group)}
                   className={cn(
-                    "w-full flex items-center gap-2 px-3 text-sm transition-colors",
+                    "w-full flex items-center gap-2 pl-5 pr-3 text-sm transition-colors",
                     isActive
                       ? "bg-accent text-accent-foreground font-medium"
                       : "text-foreground/80 hover:bg-muted"
@@ -110,25 +310,172 @@ export function ContactsSidebar({
           </div>
         )}
 
-        {sortedGroups.length === 0 && (
+        {/* Categories section (from contact keywords) */}
-          <div className="mt-2 px-3">
+        {allKeywords.length > 0 && (
-            <div className="flex items-center justify-between py-1">
+          <div className="mt-2">
-              <span className="text-xs font-medium text-muted-foreground uppercase tracking-wider">
+            <button
-                {t("tabs.groups")}
+              onClick={() => toggleSection("categories")}
-              </span>
+              className="flex items-center gap-1 px-3 py-1 w-full text-left group"
-            </div>
-            <Button
-              size="sm"
-              variant="ghost"
-              onClick={onCreateGroup}
-              className="w-full justify-start text-xs text-muted-foreground h-7"
             >
-              <Plus className="w-3 h-3 mr-1.5" />
+              {collapsed.categories ? (
-              {t("groups.create")}
+                <ChevronRight className="w-3 h-3 text-muted-foreground" />
-            </Button>
+              ) : (
+                <ChevronDown className="w-3 h-3 text-muted-foreground" />
+              )}
+              <span className="text-xs font-medium text-muted-foreground uppercase tracking-wider">
+                {t("detail.categories")}
+              </span>
+            </button>
+
+            {!collapsed.categories && allKeywords.map(([keyword, count]) => {
+              const isActive = typeof activeCategory === "object" && "keyword" in activeCategory && activeCategory.keyword === keyword;
+              return (
+                <button
+                  key={keyword}
+                  onClick={() => onSelectCategory({ keyword })}
+                  className={cn(
+                    "w-full flex items-center gap-2 pl-5 pr-3 text-sm transition-colors",
+                    isActive
+                      ? "bg-accent text-accent-foreground font-medium"
+                      : "text-foreground/80 hover:bg-muted"
+                  )}
+                  style={{ paddingBlock: 'var(--density-sidebar-py, 4px)', minHeight: '32px' }}
+                >
+                  <Tag className="w-3.5 h-3.5 flex-shrink-0" />
+                  <span className="truncate">{keyword}</span>
+                  <span className="ml-auto text-xs text-muted-foreground tabular-nums">
+                    {count}
+                  </span>
+                </button>
+              );
+            })}
           </div>
         )}
+
+        {/* Shared accounts with address books */}
+        {sharedBookGroups.map((group) => (
+          <div key={group.accountId} className="mt-2">
+            <button
+              onClick={() => toggleSection(`shared-${group.accountId}`)}
+              className="flex items-center gap-1 px-3 py-1 w-full text-left group"
+            >
+              {collapsed[`shared-${group.accountId}`] ? (
+                <ChevronRight className="w-3 h-3 text-muted-foreground" />
+              ) : (
+                <ChevronDown className="w-3 h-3 text-muted-foreground" />
+              )}
+              <Share2 className="w-3 h-3 text-muted-foreground" />
+              <span className="text-xs font-medium text-muted-foreground uppercase tracking-wider truncate">
+                {t("address_books.shared_prefix", { name: group.accountName })}
+              </span>
+            </button>
+            {!collapsed[`shared-${group.accountId}`] && group.books.map((book) => (
+              <AddressBookItem
+                key={book.id}
+                book={book}
+                isActive={typeof activeCategory === "object" && "addressBookId" in activeCategory && activeCategory.addressBookId === book.id}
+                contactCount={contactCountByBook[book.id] || 0}
+                onSelect={() => onSelectCategory({ addressBookId: book.id })}
+                onDropContacts={onDropContacts}
+              />
+            ))}
+          </div>
+        ))}
       </div>
+
+      {/* Group context menu */}
+      {groupContextMenu.data && (
+        <ContextMenu
+          ref={groupMenuRef}
+          isOpen={groupContextMenu.isOpen}
+          position={groupContextMenu.position}
+          onClose={closeGroupContextMenu}
+        >
+          <ContextMenuItem
+            icon={Pencil}
+            label={t("groups.edit")}
+            onClick={() => {
+              closeGroupContextMenu();
+              onEditGroup?.(groupContextMenu.data!.id);
+            }}
+          />
+          <ContextMenuSeparator />
+          <ContextMenuItem
+            icon={Trash2}
+            label={t("form.delete")}
+            onClick={() => {
+              closeGroupContextMenu();
+              onDeleteGroup?.(groupContextMenu.data!.id);
+            }}
+            destructive
+          />
+        </ContextMenu>
+      )}
     </div>
   );
 }
+
+function AddressBookItem({
+  book,
+  isActive,
+  contactCount,
+  onSelect,
+  onDropContacts,
+}: {
+  book: AddressBook;
+  isActive: boolean;
+  contactCount: number;
+  onSelect: () => void;
+  onDropContacts?: (contactIds: string[], addressBook: AddressBook) => void;
+}) {
+  const [isDragOver, setIsDragOver] = useState(false);
+
+  const handleDragOver = useCallback((e: DragEvent<HTMLButtonElement>) => {
+    if (!e.dataTransfer.types.includes("application/x-contact-ids")) return;
+    e.preventDefault();
+    e.dataTransfer.dropEffect = "move";
+    setIsDragOver(true);
+  }, []);
+
+  const handleDragLeave = useCallback(() => {
+    setIsDragOver(false);
+  }, []);
+
+  const handleDrop = useCallback((e: DragEvent<HTMLButtonElement>) => {
+    e.preventDefault();
+    setIsDragOver(false);
+    const data = e.dataTransfer.getData("application/x-contact-ids");
+    if (!data || !onDropContacts) return;
+    try {
+      const contactIds = JSON.parse(data) as string[];
+      if (contactIds.length > 0) {
+        onDropContacts(contactIds, book);
+      }
+    } catch {
+      // ignore invalid data
+    }
+  }, [book, onDropContacts]);
+
+  return (
+    <button
+      onClick={onSelect}
+      onDragOver={handleDragOver}
+      onDragLeave={handleDragLeave}
+      onDrop={handleDrop}
+      className={cn(
+        "w-full flex items-center gap-2 pl-5 pr-3 text-sm transition-colors",
+        isActive
+          ? "bg-accent text-accent-foreground font-medium"
+          : "text-foreground/80 hover:bg-muted",
+        isDragOver && "bg-primary/20 ring-2 ring-primary/50"
+      )}
+      style={{ paddingBlock: 'var(--density-sidebar-py, 4px)', minHeight: '32px' }}
+    >
+      <Book className="w-4 h-4 flex-shrink-0" />
+      <span className="truncate">{book.name}</span>
+      <span className="ml-auto text-xs text-muted-foreground tabular-nums">
+        {contactCount}
+      </span>
+    </button>
+  );
+}

components/email/calendar-invitation-banner.tsx

@@ -360,6 +360,7 @@ export function CalendarInvitationBanner({ email }: CalendarInvitationBannerProp
   const client = useAuthStore((s) => s.client);
   const currentUserEmail = useAuthStore((s) => s.primaryIdentity?.email);
   const calendarInvitationParsingEnabled = useSettingsStore((s) => s.calendarInvitationParsingEnabled);
+  const timeFormat = useSettingsStore((s) => s.timeFormat);
   const { calendars, supportsCalendar, importEvents, rsvpEvent, updateEvent, events: storeEvents, setSelectedDate } = useCalendarStore();
 
   const [state, setState] = useState<BannerState>('loading');
@@ -544,6 +545,7 @@ export function CalendarInvitationBanner({ email }: CalendarInvitationBannerProp
           dtStart: parsedEvent.start || undefined,
           dtEnd: summary?.end || undefined,
           timeZone: parsedEvent.timeZone || undefined,
+          isAllDay: parsedEvent.showWithoutTime || false,
           sequence: parsedEvent.sequence,
           status: imipStatus,
         });
@@ -659,16 +661,26 @@ export function CalendarInvitationBanner({ email }: CalendarInvitationBannerProp
     }
   };
 
+  const isAllDayEvent = parsedEvent?.showWithoutTime ?? false;
+
   const formatDateTime = (dateStr: string | null) => {
     if (!dateStr) return '';
     const date = new Date(dateStr);
     if (isNaN(date.getTime())) return dateStr;
+    if (isAllDayEvent) {
+      return format.dateTime(date, {
+        weekday: 'short',
+        month: 'short',
+        day: 'numeric',
+      });
+    }
     return format.dateTime(date, {
       weekday: 'short',
       month: 'short',
       day: 'numeric',
       hour: 'numeric',
       minute: '2-digit',
+      hour12: timeFormat === '12h',
     });
   };
 

components/email/email-composer.tsx

@@ -5,13 +5,20 @@ import { useFocusTrap } from "@/hooks/use-focus-trap";
 import { useTranslations } from "next-intl";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
-import { X, Paperclip, Send, Save, Check, Loader2, AlertCircle, FileText, BookmarkPlus } from "lucide-react";
+import { X, Paperclip, Send, Save, Check, Loader2, AlertCircle, FileText, BookmarkPlus, ShieldCheck, Lock } from "lucide-react";
-import { cn, formatFileSize } from "@/lib/utils";
+import { cn, formatFileSize, formatDateTime } from "@/lib/utils";
 import { debug } from "@/lib/debug";
 import { toast } from "@/stores/toast-store";
 import { sanitizeEmailHtml } from "@/lib/email-sanitization";
 import { useAuthStore } from "@/stores/auth-store";
 import { useIdentityStore } from "@/stores/identity-store";
+import { useSmimeStore } from "@/stores/smime-store";
+import { useEmailStore } from "@/stores/email-store";
+import { useSettingsStore } from "@/stores/settings-store";
+import { buildMimeMessage, wrapCmsAsSmimeMessage } from "@/lib/smime/mime-builder";
+import type { MimeAttachment } from "@/lib/smime/mime-builder";
+import { smimeSign } from "@/lib/smime/smime-sign";
+import { smimeEncrypt } from "@/lib/smime/smime-encrypt";
 import { useContactStore } from "@/stores/contact-store";
 import { useTemplateStore } from "@/stores/template-store";
 import { SubAddressHelper } from "@/components/identity/sub-address-helper";
@@ -20,6 +27,7 @@ import { substitutePlaceholders } from "@/lib/template-utils";
 import { TemplatePicker } from "@/components/templates/template-picker";
 import { TemplateForm } from "@/components/templates/template-form";
 import type { EmailTemplate } from "@/lib/template-types";
+import { appendPlainTextSignature, getPlainTextSignature } from "@/lib/signature-utils";
 
 export interface ComposerDraftData {
   to: string;
@@ -48,6 +56,7 @@ interface EmailComposerProps {
     fromEmail?: string;
     fromName?: string;
     identityId?: string;
+    attachments?: Array<{ blobId: string; name: string; type: string; size: number }>;
   }) => void | Promise<void>;
   onClose?: () => void;
   onDiscardDraft?: (draftId: string) => void;
@@ -80,6 +89,7 @@ export function EmailComposer({
 }: EmailComposerProps) {
   const t = useTranslations('email_composer');
   const tCommon = useTranslations('common');
+  const timeFormat = useSettingsStore((state) => state.timeFormat);
 
   // Initialize with reply/forward data if provided
   const getInitialTo = () => {
@@ -118,7 +128,7 @@ export function EmailComposer({
     const prefix = initialDraftText || "";
     if (!replyTo?.body && !replyTo?.htmlBody) return prefix;
 
-    const date = replyTo.receivedAt ? new Date(replyTo.receivedAt).toLocaleString() : "";
+    const date = replyTo.receivedAt ? formatDateTime(replyTo.receivedAt, timeFormat, { weekday: 'short', year: 'numeric', month: 'short', day: 'numeric' }) : "";
     const from = replyTo.from?.[0];
     const fromStr = from ? `${from.name || from.email}` : tCommon('unknown');
 
@@ -169,6 +179,11 @@ export function EmailComposer({
   const [showSaveAsTemplate, setShowSaveAsTemplate] = useState(false);
   const [showCloseDialog, setShowCloseDialog] = useState(false);
   const [showAllAttachments, setShowAllAttachments] = useState(false);
+  const [smimeSign_, setSmimeSign] = useState(false);
+  const [smimeEncrypt_, setSmimeEncrypt] = useState(false);
+  const [smimePassphrasePrompt, setSmimePassphrasePrompt] = useState<{ keyId: string; resolve: (passphrase: string) => void; reject: () => void } | null>(null);
+  const [smimePassphraseInput, setSmimePassphraseInput] = useState('');
+  const [smimePassphraseError, setSmimePassphraseError] = useState('');
 
   const saveTemplateModalRef = useFocusTrap({
     isActive: showSaveAsTemplate,
@@ -185,8 +200,43 @@ export function EmailComposer({
   const { client } = useAuthStore();
   const identities = useIdentityStore((s) => s.identities);
   const primaryIdentity = identities[0] ?? null;
+  const currentIdentity = selectedIdentityId
+    ? identities.find((identity) => identity.id === selectedIdentityId) || primaryIdentity
+    : primaryIdentity;
+  const composerSignatureHtml = currentIdentity?.htmlSignature
+    ? `<div>${sanitizeEmailHtml(currentIdentity.htmlSignature)}</div>`
+    : currentIdentity?.textSignature
+      ? `<div>${getPlainTextSignature(currentIdentity).replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/\n/g, '<br>')}</div>`
+      : '';
   const getAutocomplete = useContactStore((s) => s.getAutocomplete);
   const addTemplate = useTemplateStore((s) => s.addTemplate);
+  const sendRawEmail = useEmailStore((s) => s.sendRawEmail);
+  const smimeStore = useSmimeStore();
+
+  // Determine S/MIME availability for the selected identity
+  const currentSmimeIdentityId = selectedIdentityId || primaryIdentity?.id;
+  const smimeKeyRecord = currentSmimeIdentityId ? smimeStore.getKeyRecordForIdentity(currentSmimeIdentityId) : undefined;
+  const canSmimeSign = !!smimeKeyRecord;
+  const canSmimeEncrypt = (() => {
+    if (!smimeKeyRecord) return false;
+    const toAddrs = to.split(',').map(e => e.trim()).filter(Boolean);
+    const ccAddrs = cc.split(',').map(e => e.trim()).filter(Boolean);
+    const bccAddrs = bcc.split(',').map(e => e.trim()).filter(Boolean);
+    const allRecipients = [...toAddrs, ...ccAddrs, ...bccAddrs];
+    if (allRecipients.length === 0) return false;
+    const { missing } = smimeStore.getRecipientCerts(allRecipients);
+    return missing.length === 0;
+  })();
+
+  // Initialize S/MIME defaults from store when identity changes
+  useEffect(() => {
+    if (currentSmimeIdentityId) {
+      setSmimeSign(!!smimeStore.defaultSignIdentity[currentSmimeIdentityId] && canSmimeSign);
+    }
+    setSmimeEncrypt(smimeStore.defaultEncrypt && canSmimeEncrypt);
+  // Only run when identity changes, not on every recipient edit
+  // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [currentSmimeIdentityId]);
 
   // Keep a ref to current state for the unmount save
   const stateRef = useRef({ to, cc, bcc, subject, body, showCc, showBcc, selectedIdentityId, subAddressTag, draftId });
@@ -486,10 +536,6 @@ export function EmailComposer({
     setSaveStatus('saving');
 
     // Get the selected identity or primary identity
-    const currentIdentity = selectedIdentityId
-      ? identities.find(id => id.id === selectedIdentityId)
-      : primaryIdentity;
-
     // Generate sub-addressed email if tag is set
     const fromEmail = currentIdentity?.email
       ? subAddressTag
@@ -608,10 +654,6 @@ export function EmailComposer({
       }
     }
 
-    const currentIdentity = selectedIdentityId
-      ? identities.find(id => id.id === selectedIdentityId)
-      : primaryIdentity;
-
     const fromEmail = currentIdentity?.email
       ? subAddressTag
         ? generateSubAddress(currentIdentity.email, subAddressTag)
@@ -619,19 +661,43 @@ export function EmailComposer({
       : undefined;
 
     // Append signature from the selected identity
-    let finalBody = body;
+    let finalBody = appendPlainTextSignature(body, currentIdentity);
-    if (currentIdentity?.textSignature) {
+
-      finalBody = body + '\n\n-- \n' + currentIdentity.textSignature;
+    // Append quoted original text for the plain text part in reply/forward
+    if (replyTo && (mode === 'reply' || mode === 'replyAll' || mode === 'forward')) {
+      const originalText = replyTo.body || '';
+      if (originalText) {
+        const date = replyTo.receivedAt ? formatDateTime(replyTo.receivedAt, timeFormat, { weekday: 'short', year: 'numeric', month: 'short', day: 'numeric' }) : '';
+        const fromAddr = replyTo.from?.[0];
+        const fromStr = fromAddr ? `${fromAddr.name || fromAddr.email}` : tCommon('unknown');
+
+        if (mode === 'forward') {
+          finalBody += `\n\n---------- ${t('prefix.forward')} ----------\nFrom: ${fromStr}\nDate: ${date}\nSubject: ${replyTo.subject || ''}\n\n${originalText}`;
+        } else {
+          finalBody += `\n\nOn ${date}, ${fromStr} wrote:\n> ${originalText.split('\n').join('\n> ')}`;
+        }
+      }
     }
 
-    // Build HTML body when replying/forwarding with original HTML content
+    // Build HTML signature block (prefer htmlSignature, fall back to escaped textSignature)
+    const buildSignatureHtml = (): string => {
+      if (currentIdentity?.htmlSignature) {
+        return `<br><br>-- <br>${sanitizeEmailHtml(currentIdentity.htmlSignature)}`;
+      }
+      if (currentIdentity?.textSignature) {
+        return `<br><br>-- <br>${currentIdentity.textSignature.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/\n/g, '<br>')}`;
+      }
+      return '';
+    };
+
+    // Build HTML body
     let finalHtmlBody: string | undefined;
+    const signatureHtml = buildSignatureHtml();
+
     if (replyTo?.htmlBody && (mode === 'reply' || mode === 'replyAll' || mode === 'forward')) {
+      // Reply/forward with original HTML content
       const escapedBody = body.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/\n/g, '<br>');
-      const signatureHtml = currentIdentity?.textSignature
+      const date = replyTo.receivedAt ? formatDateTime(replyTo.receivedAt, timeFormat, { weekday: 'short', year: 'numeric', month: 'short', day: 'numeric' }) : '';
-        ? `<br><br>-- <br>${currentIdentity.textSignature.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/\n/g, '<br>')}`
-        : '';
-      const date = replyTo.receivedAt ? new Date(replyTo.receivedAt).toLocaleString() : '';
       const fromAddr = replyTo.from?.[0];
       const fromStr = fromAddr ? `${fromAddr.name || fromAddr.email}` : tCommon('unknown');
       const quoteHeader = mode === 'forward'
@@ -639,21 +705,129 @@ export function EmailComposer({
         : `On ${date}, ${fromStr} wrote:<br>`;
 
       finalHtmlBody = `<div>${escapedBody}</div>${signatureHtml}<br><div><div>${quoteHeader}</div><blockquote style="margin:0 0 0 0.8ex;border-left:2px solid #ccc;padding-left:1ex">${replyTo.htmlBody}</blockquote></div>`;
+    } else if (signatureHtml) {
+      // New compose or plain-text reply — include HTML body with signature
+      const escapedBody = body.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/\n/g, '<br>');
+      finalHtmlBody = `<div>${escapedBody}</div>${signatureHtml}`;
     }
 
     try {
-      await onSend?.({
+      // S/MIME send pipeline: build raw MIME → sign → encrypt → sendRawEmail
-        to: toAddresses,
+      if ((smimeSign_ || smimeEncrypt_) && client && currentIdentity?.id) {
-        cc: ccAddresses,
+        // 1. Resolve S/MIME key
-        bcc: bccAddresses,
+        if (smimeSign_ && !smimeKeyRecord) {
-        subject,
+          throw new Error('No S/MIME key bound to this identity');
-        body: finalBody,
+        }
-        htmlBody: finalHtmlBody,
+
-        draftId: finalDraftId || undefined,
+        // 2. Ensure key is unlocked for signing
-        fromEmail,
+        if (smimeSign_ && smimeKeyRecord && !smimeStore.isKeyUnlocked(smimeKeyRecord.id)) {
-        fromName: currentIdentity?.name || undefined,
+          const passphrase = await new Promise<string>((resolve, reject) => {
-        identityId: currentIdentity?.id,
+            setSmimePassphrasePrompt({ keyId: smimeKeyRecord.id, resolve, reject });
-      });
+          });
+          try {
+            await smimeStore.unlockKey(smimeKeyRecord.id, passphrase);
+          } finally {
+            setSmimePassphrasePrompt(null);
+            setSmimePassphraseInput('');
+            setSmimePassphraseError('');
+          }
+        }
+
+        // 3. Resolve attachments as ArrayBuffers
+        const mimeAttachments: MimeAttachment[] = [];
+        for (const att of attachments) {
+          if (att.error || att.uploading) continue;
+          let content: ArrayBuffer;
+          if (att.file.size > 0) {
+            content = await att.file.arrayBuffer();
+          } else if (att.blobId && client) {
+            content = await client.fetchBlobArrayBuffer(att.blobId, att.file.name, att.file.type);
+          } else {
+            continue;
+          }
+          mimeAttachments.push({
+            filename: att.file.name,
+            contentType: att.file.type || 'application/octet-stream',
+            content,
+          });
+        }
+
+        // 4. Build canonical MIME
+        const mimeBytes = buildMimeMessage({
+          from: { name: currentIdentity.name || undefined, email: fromEmail || currentIdentity.email },
+          to: toAddresses.map(e => ({ email: e })),
+          cc: ccAddresses.length > 0 ? ccAddresses.map(e => ({ email: e })) : undefined,
+          bcc: bccAddresses.length > 0 ? bccAddresses.map(e => ({ email: e })) : undefined,
+          subject,
+          textBody: finalBody,
+          htmlBody: finalHtmlBody,
+          attachments: mimeAttachments.length > 0 ? mimeAttachments : undefined,
+        });
+
+        let payload: Blob = new Blob([mimeBytes.buffer as ArrayBuffer], { type: 'message/rfc822' });
+
+        const smimeHeaders = {
+          from: { name: currentIdentity.name || undefined, email: fromEmail || currentIdentity.email },
+          to: toAddresses.map(e => ({ email: e })),
+          cc: ccAddresses.length > 0 ? ccAddresses.map(e => ({ email: e })) : undefined,
+          subject,
+        };
+
+        // 5. Sign if enabled
+        if (smimeSign_ && smimeKeyRecord) {
+          const privateKey = smimeStore.getUnlockedKey(smimeKeyRecord.id);
+          if (!privateKey) throw new Error('S/MIME key is not unlocked');
+          const cmsBlob = await smimeSign(
+            mimeBytes,
+            privateKey,
+            smimeKeyRecord.certificate,
+            smimeKeyRecord.certificateChain || [],
+          );
+          const cmsBytes = new Uint8Array(await cmsBlob.arrayBuffer());
+          payload = wrapCmsAsSmimeMessage(cmsBytes, { ...smimeHeaders, smimeType: 'signed-data' });
+        }
+
+        // 6. Encrypt if enabled
+        if (smimeEncrypt_ && smimeKeyRecord) {
+          const allRecipients = [...toAddresses, ...ccAddresses, ...bccAddresses];
+          const { found, missing } = smimeStore.getRecipientCerts(allRecipients);
+          if (missing.length > 0) {
+            throw new Error(`Missing certificates for: ${missing.join(', ')}`);
+          }
+          const recipientCertsDer = found.map(c => c.certificate instanceof ArrayBuffer ? c.certificate : new Uint8Array(c.certificate as ArrayBuffer).buffer);
+          const payloadBytes = new Uint8Array(await payload.arrayBuffer());
+          const cmsBlob = await smimeEncrypt(
+            payloadBytes,
+            recipientCertsDer,
+            smimeKeyRecord.certificate,
+          );
+          const cmsBytes = new Uint8Array(await cmsBlob.arrayBuffer());
+          payload = wrapCmsAsSmimeMessage(cmsBytes, { ...smimeHeaders, smimeType: 'enveloped-data' });
+        }
+
+        // 7. Send via raw email path
+        await sendRawEmail(client, payload, currentIdentity.id);
+      } else {
+        // Standard JMAP send path
+        // Collect uploaded attachment blobIds for the send request
+        const uploadedAttachments = attachments
+          .filter(att => att.blobId && !att.uploading && !att.error)
+          .map(att => ({ blobId: att.blobId!, name: att.file.name, type: att.file.type || 'application/octet-stream', size: att.file.size }));
+
+        await onSend?.({
+          to: toAddresses,
+          cc: ccAddresses,
+          bcc: bccAddresses,
+          subject,
+          body: finalBody,
+          htmlBody: finalHtmlBody,
+          draftId: finalDraftId || undefined,
+          fromEmail,
+          fromName: currentIdentity?.name || undefined,
+          identityId: currentIdentity?.id,
+          attachments: uploadedAttachments.length > 0 ? uploadedAttachments : undefined,
+        });
+      }
 
       setTo("");
       setCc("");
@@ -950,13 +1124,20 @@ export function EmailComposer({
           />
         </div>
 
+        {composerSignatureHtml && (
+          <div
+            className="px-4 pb-3 text-sm leading-6 text-foreground break-words [&_a]:text-primary [&_a]:underline-offset-2 [&_a:hover]:underline"
+            dangerouslySetInnerHTML={{ __html: `<div>-- </div>${composerSignatureHtml}` }}
+          />
+        )}
+
         {/* Quoted original HTML */}
         {replyTo?.htmlBody && (mode === 'reply' || mode === 'replyAll' || mode === 'forward') && (
           <div className="border-t border-border">
             <div className="px-4 py-2 text-xs text-muted-foreground">
               {mode === 'forward'
                 ? `---------- ${t('prefix.forward')} ----------`
-                : `${replyTo.receivedAt ? new Date(replyTo.receivedAt).toLocaleString() : ''}, ${replyTo.from?.[0]?.name || replyTo.from?.[0]?.email || tCommon('unknown')}:`
+                : `${replyTo.receivedAt ? formatDateTime(replyTo.receivedAt, timeFormat, { weekday: 'short', year: 'numeric', month: 'short', day: 'numeric' }) : ''}, ${replyTo.from?.[0]?.name || replyTo.from?.[0]?.email || tCommon('unknown')}:`
               }
             </div>
             <div
@@ -1059,6 +1240,32 @@ export function EmailComposer({
             >
               <BookmarkPlus className="w-4 h-4" />
             </Button>
+
+            {/* S/MIME toggles */}
+            {canSmimeSign && (
+              <>
+                <div className="w-px h-5 bg-border mx-1" />
+                <Button
+                  variant="ghost"
+                  size="icon"
+                  onClick={() => setSmimeSign(v => !v)}
+                  className={cn("h-9 w-9", smimeSign_ && "bg-primary/10 text-primary")}
+                  title={smimeSign_ ? t('smime_sign_on') : t('smime_sign_off')}
+                >
+                  <ShieldCheck className="w-4 h-4" />
+                </Button>
+                <Button
+                  variant="ghost"
+                  size="icon"
+                  onClick={() => setSmimeEncrypt(v => !v)}
+                  disabled={!canSmimeEncrypt}
+                  className={cn("h-9 w-9", smimeEncrypt_ && "bg-primary/10 text-primary")}
+                  title={smimeEncrypt_ ? t('smime_encrypt_on') : canSmimeEncrypt ? t('smime_encrypt_off') : t('smime_encrypt_unavailable')}
+                >
+                  <Lock className="w-4 h-4" />
+                </Button>
+              </>
+            )}
           </div>
 
           {/* Right side - Discard + Send (desktop) */}
@@ -1117,6 +1324,60 @@ export function EmailComposer({
         </div>
       )}
 
+      {/* S/MIME passphrase prompt */}
+      {smimePassphrasePrompt && (
+        <div
+          className="fixed inset-0 bg-black/50 backdrop-blur-[1px] flex items-center justify-center z-[60] p-4 animate-in fade-in duration-150"
+        >
+          <div
+            role="dialog"
+            aria-modal="true"
+            onClick={(e) => e.stopPropagation()}
+            className="bg-background border border-border rounded-lg shadow-xl w-full max-w-sm animate-in zoom-in-95 duration-200"
+          >
+            <div className="p-6">
+              <h2 className="text-lg font-semibold text-foreground">{t('smime_unlock_title')}</h2>
+              <p className="mt-2 text-sm text-muted-foreground">{t('smime_unlock_message')}</p>
+              <input
+                type="password"
+                autoFocus
+                value={smimePassphraseInput}
+                onChange={(e) => {
+                  setSmimePassphraseInput(e.target.value);
+                  setSmimePassphraseError('');
+                }}
+                onKeyDown={(e) => {
+                  if (e.key === 'Enter' && smimePassphraseInput) {
+                    smimePassphrasePrompt.resolve(smimePassphraseInput);
+                  }
+                }}
+                placeholder={t('smime_passphrase_placeholder')}
+                className="mt-3 w-full px-3 py-2 border border-border rounded-md text-sm bg-background text-foreground outline-none focus:ring-2 focus:ring-primary"
+              />
+              {smimePassphraseError && (
+                <p className="mt-1 text-xs text-red-500">{smimePassphraseError}</p>
+              )}
+            </div>
+            <div className="flex items-center justify-end gap-3 px-6 pb-6">
+              <Button variant="outline" onClick={() => {
+                smimePassphrasePrompt.reject();
+                setSmimePassphrasePrompt(null);
+                setSmimePassphraseInput('');
+                setSmimePassphraseError('');
+              }}>
+                {t('cancel')}
+              </Button>
+              <Button
+                disabled={!smimePassphraseInput}
+                onClick={() => smimePassphrasePrompt.resolve(smimePassphraseInput)}
+              >
+                {t('smime_unlock_button')}
+              </Button>
+            </div>
+          </div>
+        </div>
+      )}
+
       {showCloseDialog && (
         <div
           className="fixed inset-0 bg-black/50 backdrop-blur-[1px] flex items-center justify-center z-[60] p-4 animate-in fade-in duration-150"

components/email/email-context-menu.tsx

@@ -28,6 +28,7 @@ import {
   Folder,
   ShieldAlert,
   ShieldCheck,
+  EditIcon,
 } from "lucide-react";
 import { cn, buildMailboxTree, MailboxNode } from "@/lib/utils";
 import { useSettingsStore, KEYWORD_PALETTE } from "@/stores/settings-store";
@@ -60,6 +61,7 @@ interface EmailContextMenuProps {
   onMoveToMailbox?: (mailboxId: string) => void;
   onMarkAsSpam?: () => void;
   onUndoSpam?: () => void;
+  onEditDraft?: () => void;
   // Batch actions
   onBatchMarkAsRead?: (read: boolean) => void;
   onBatchDelete?: () => void;
@@ -126,12 +128,14 @@ export function EmailContextMenu({
   onBatchMoveToMailbox,
   onBatchMarkAsSpam,
   onBatchUndoSpam,
+  onEditDraft,
 }: EmailContextMenuProps) {
   const t = useTranslations("context_menu");
   const tColor = useTranslations("email_viewer.color_tag");
   const emailKeywords = useSettingsStore((state) => state.emailKeywords);
   const isUnread = !email.keywords?.$seen;
   const isStarred = email.keywords?.$flagged;
+  const isDraft = email.keywords?.['$draft'] === true;
   const currentColor = getCurrentColor(email.keywords);
   const showBatchActions = isMultiSelect && selectedCount > 1;
   const isInJunkFolder = currentMailboxRole === 'junk';
@@ -188,6 +192,18 @@ export function EmailContextMenu({
         </ContextMenuHeader>
       )}
 
+      {/* Edit Draft - only for single draft emails */}
+      {!showBatchActions && isDraft && onEditDraft && (
+        <>
+          <ContextMenuItem
+            icon={EditIcon}
+            label={t("edit_draft")}
+            onClick={() => handleAction(onEditDraft)}
+          />
+          <ContextMenuSeparator />
+        </>
+      )}
+
       {/* Single email actions - Reply, Reply All, Forward */}
       {!showBatchActions && (
         <>

components/email/email-list.tsx

@@ -37,6 +37,7 @@ interface EmailListProps {
   onMoveToMailbox?: (emailId: string, mailboxId: string) => void;
   onMarkAsSpam?: (email: Email) => void;
   onUndoSpam?: (email: Email) => void;
+  onEditDraft?: (email: Email) => void;
 }
 
 export function EmailList({
@@ -57,6 +58,7 @@ export function EmailList({
   onMarkAsSpam,
   onUndoSpam,
   onMoveToMailbox,
+  onEditDraft,
 }: EmailListProps) {
   const t = useTranslations('email_list');
   const { client } = useAuthStore();
@@ -467,6 +469,7 @@ export function EmailList({
           onMoveToMailbox={(mailboxId) => onMoveToMailbox?.(contextMenu.data!.id, mailboxId)}
           onMarkAsSpam={() => onMarkAsSpam?.(contextMenu.data!)}
           onUndoSpam={() => onUndoSpam?.(contextMenu.data!)}
+          onEditDraft={() => onEditDraft?.(contextMenu.data!)}
           onBatchMarkAsRead={(read) => client && batchMarkAsRead(client, read)}
           onBatchDelete={() => client && batchDelete(client)}
           onBatchMoveToMailbox={(mailboxId) => client && batchMoveToMailbox(client, mailboxId)}

components/email/smime-status-banner.tsx

@@ -0,0 +1,116 @@
+"use client";
+
+import React from "react";
+import { ShieldCheck, ShieldAlert, ShieldX, Lock, LockOpen, AlertTriangle, Info } from "lucide-react";
+import { cn } from "@/lib/utils";
+import { useTranslations } from "next-intl";
+import type { SmimeStatus } from "@/lib/smime/types";
+
+interface SmimeStatusBannerProps {
+  status: SmimeStatus;
+  onUnlockKey?: () => void;
+  className?: string;
+}
+
+export function SmimeStatusBanner({ status, onUnlockKey, className }: SmimeStatusBannerProps) {
+  const t = useTranslations('smime');
+
+  const items: Array<{
+    icon: React.ReactNode;
+    text: string;
+    variant: 'success' | 'warning' | 'error' | 'info';
+  }> = [];
+
+  // Encryption status
+  if (status.isEncrypted) {
+    if (status.decryptionError) {
+      if (status.decryptionError === 'locked') {
+        items.push({
+          icon: <Lock className="w-4 h-4" />,
+          text: t('unlock_key_desc'),
+          variant: 'warning',
+        });
+      } else {
+        items.push({
+          icon: <ShieldX className="w-4 h-4" />,
+          text: t('status_encrypted_failed'),
+          variant: 'error',
+        });
+      }
+    } else {
+      items.push({
+        icon: <LockOpen className="w-4 h-4" />,
+        text: t('status_encrypted_ok'),
+        variant: 'success',
+      });
+    }
+  }
+
+  // Signature status
+  if (status.isSigned) {
+    if (status.signatureValid === true) {
+      if (status.signerEmailMatch === false) {
+        items.push({
+          icon: <AlertTriangle className="w-4 h-4" />,
+          text: t('status_signed_mismatch'),
+          variant: 'warning',
+        });
+      } else {
+        items.push({
+          icon: <ShieldCheck className="w-4 h-4" />,
+          text: t('status_signed_valid'),
+          variant: 'success',
+        });
+      }
+    } else if (status.signatureValid === false) {
+      items.push({
+        icon: <ShieldAlert className="w-4 h-4" />,
+        text: status.signatureError || t('status_signed_invalid'),
+        variant: 'error',
+      });
+    }
+  }
+
+  // Unsupported S/MIME
+  if (status.unsupportedReason) {
+    items.push({
+      icon: <Info className="w-4 h-4" />,
+      text: t('status_unsupported'),
+      variant: 'info',
+    });
+  }
+
+  if (items.length === 0) return null;
+
+  const variantStyles = {
+    success: 'bg-green-50 dark:bg-green-950/30 text-green-700 dark:text-green-400 border-green-200 dark:border-green-800',
+    warning: 'bg-yellow-50 dark:bg-yellow-950/30 text-yellow-700 dark:text-yellow-400 border-yellow-200 dark:border-yellow-800',
+    error: 'bg-red-50 dark:bg-red-950/30 text-red-700 dark:text-red-400 border-red-200 dark:border-red-800',
+    info: 'bg-blue-50 dark:bg-blue-950/30 text-blue-700 dark:text-blue-400 border-blue-200 dark:border-blue-800',
+  };
+
+  return (
+    <div className={cn("flex flex-col gap-1.5 py-1", className)}>
+      {items.map((item, i) => (
+        <div
+          key={i}
+          className={cn(
+            "flex items-center gap-2 px-3 py-1.5 rounded-md text-sm border",
+            variantStyles[item.variant],
+          )}
+        >
+          {item.icon}
+          <span className="flex-1">{item.text}</span>
+          {item.variant === 'warning' && status.decryptionError === 'locked' && onUnlockKey && (
+            <button
+              onClick={onUnlockKey}
+              className="text-xs font-medium underline hover:no-underline"
+            >
+              {t('unlock_key')}
+            </button>
+          )}
+        </div>
+      ))}
+    </div>
+  );
+}

components/email/thread-conversation-view.tsx

@@ -4,6 +4,7 @@ import { useState, useEffect, useMemo } from "react";
 import DOMPurify from "dompurify";
 import { Email, ThreadGroup } from "@/lib/jmap/types";
 import { EMAIL_SANITIZE_CONFIG, collapseBlockedImageContainers } from "@/lib/email-sanitization";
+import { hasMeaningfulHtmlBody } from "@/lib/signature-utils";
 import { transformInlineStyles, transformColorForDarkMode, transformBgColorForDarkMode } from "@/lib/color-transform";
 import { useThemeStore } from "@/stores/theme-store";
 import { Avatar } from "@/components/ui/avatar";
@@ -225,6 +226,7 @@ function EmailCard({
   const resolvedTheme = useThemeStore((state) => state.resolvedTheme);
   const density = useSettingsStore((state) => state.density);
   const mailAttachmentAction = useSettingsStore((state) => state.mailAttachmentAction);
+  const emailAlwaysLightMode = useSettingsStore((state) => state.emailAlwaysLightMode);
   const sender = email.from?.[0];
   const isUnread = !email.keywords?.$seen;
   const isStarred = email.keywords?.$flagged;
@@ -315,7 +317,14 @@ function EmailCard({
 
       if (email.htmlBody?.[0]?.partId && email.bodyValues[email.htmlBody[0].partId]) {
         htmlContent = email.bodyValues[email.htmlBody[0].partId].value;
-        useHtmlVersion = !!htmlContent;
+        // Prefer textBody when HTML is auto-generated minimal wrapper (no rich formatting).
+        // Server-generated HTML from text/plain emails often lacks <br> tags, collapsing newlines.
+        const hasTextBody = email.textBody?.[0]?.partId && email.bodyValues[email.textBody[0].partId];
+        if (hasTextBody && htmlContent) {
+          useHtmlVersion = hasMeaningfulHtmlBody(htmlContent);
+        } else {
+          useHtmlVersion = !!htmlContent;
+        }
       }
 
       if (useHtmlVersion && htmlContent) {
@@ -363,7 +372,7 @@ function EmailCard({
             node.setAttribute('rel', 'noopener noreferrer');
           }
 
-          if (resolvedTheme === 'dark') {
+          if (resolvedTheme === 'dark' && !emailAlwaysLightMode) {
             if (htmlNode.style) {
               const originalStyles = htmlNode.style.cssText;
               const transformedStyles = transformInlineStyles(originalStyles, 'dark');
@@ -403,7 +412,6 @@ function EmailCard({
           .replace(/&/g, '&amp;')
           .replace(/</g, '&lt;')
           .replace(/>/g, '&gt;')
-          .replace(/\n/g, '<br>')
           .replace(/(https?:\/\/[^\s<]+)/g, '<a href="$1" target="_blank" rel="noopener noreferrer" class="text-primary hover:underline">$1</a>');
         return { html: htmlEscaped, isHtml: false };
       }
@@ -411,11 +419,15 @@ function EmailCard({
 
     // Fallback to preview
     if (email.preview) {
-      return { html: email.preview.replace(/\n/g, '<br>'), isHtml: false };
+      const previewHtml = email.preview
+        .replace(/&/g, '&amp;')
+        .replace(/</g, '&lt;')
+        .replace(/>/g, '&gt;');
+      return { html: previewHtml, isHtml: false };
     }
 
     return { html: "", isHtml: false };
-  }, [email, allowExternal, resolvedTheme, cidBlobUrls]);
+  }, [email, allowExternal, resolvedTheme, emailAlwaysLightMode, cidBlobUrls]);
 
   return (
     <div className={cn(
@@ -513,12 +525,14 @@ function EmailCard({
           <div style={{ padding: 'var(--density-card-p)' }}>
             <div
               className={cn(
-                "prose prose-sm max-w-none dark:prose-invert",
+                "prose prose-sm max-w-none",
+                !emailAlwaysLightMode && "dark:prose-invert",
                 "prose-p:my-2 prose-headings:my-3",
                 "prose-a:text-primary prose-a:no-underline hover:prose-a:underline",
                 "[&_table]:border-collapse [&_td]:p-2 [&_th]:p-2",
                 "[&_img]:max-w-full [&_img]:h-auto"
               )}
+              style={!emailContent.isHtml ? { whiteSpace: 'pre-wrap', fontFamily: 'ui-monospace, "SF Mono", Consolas, monospace', fontSize: '13px' } : undefined}
               dangerouslySetInnerHTML={{ __html: emailContent.html }}
             />
           </div>

components/identity/identity-manager-modal.tsx

@@ -2,7 +2,7 @@
 
 import { useEffect, useState, useCallback } from 'react';
 import { useTranslations } from 'next-intl';
-import { X, Mail, Pencil, Trash2, Plus, AlertTriangle } from 'lucide-react';
+import { X, Mail, Pencil, Trash2, Plus, AlertTriangle, Star } from 'lucide-react';
 import { cn } from '@/lib/utils';
 import { Button } from '@/components/ui/button';
 import { ConfirmDialog } from '@/components/ui/confirm-dialog';
@@ -19,6 +19,12 @@ import { toast } from '@/stores/toast-store';
 import { useFocusTrap } from '@/hooks/use-focus-trap';
 import { useConfirmDialog } from '@/hooks/use-confirm-dialog';
 
+function emailMatchesUsername(email: string, username: string): boolean {
+  if (email === username) return true;
+  if (!username.includes('@') && email.split('@')[0] === username) return true;
+  return false;
+}
+
 interface IdentityFormData {
   name: string;
   email: string;
@@ -38,7 +44,9 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
   const tNotif = useTranslations('notifications');
 
   const client = useAuthStore((state) => state.client);
-  const { identities, addIdentity, updateIdentityLocal, removeIdentity } = useIdentityStore();
+  const identities = useIdentityStore((state) => state.identities);
+  const preferredPrimaryId = useIdentityStore((state) => state.preferredPrimaryId);
+  const setPreferredPrimary = useIdentityStore((state) => state.setPreferredPrimary);
   const syncIdentities = useSyncIdentities();
 
   const [editingId, setEditingId] = useState<string | null>(null);
@@ -46,6 +54,40 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
   const [deletingId, setDeletingId] = useState<string | null>(null);
   const { dialogProps: confirmDialogProps, confirm: confirmDialog } = useConfirmDialog();
 
+  // Re-fetch all identities from server and update stores
+  const refreshIdentities = useCallback(async () => {
+    if (!client) return;
+    try {
+      const serverIdentities = await client.getIdentities();
+      const username = useAuthStore.getState().username;
+      const preferredPrimaryId = useIdentityStore.getState().preferredPrimaryId;
+      const sorted = [...serverIdentities].sort((a, b) => {
+        const aMatch = emailMatchesUsername(a.email, username || '');
+        const bMatch = emailMatchesUsername(b.email, username || '');
+        if (aMatch && !bMatch) return -1;
+        if (!aMatch && bMatch) return 1;
+        if (aMatch && bMatch) {
+          if (!a.mayDelete && b.mayDelete) return -1;
+          if (a.mayDelete && !b.mayDelete) return 1;
+        }
+        return 0;
+      });
+      // Move preferred primary to front if set
+      if (preferredPrimaryId) {
+        const idx = sorted.findIndex((id) => id.id === preferredPrimaryId);
+        if (idx > 0) {
+          const [preferred] = sorted.splice(idx, 1);
+          sorted.unshift(preferred);
+        }
+      }
+      useIdentityStore.getState().setIdentities(sorted);
+      syncIdentities();
+    } catch (error) {
+      const message = error instanceof Error ? error.message : 'Failed to refresh identities';
+      toast.error(message);
+    }
+  }, [client, syncIdentities]);
+
   // Focus trap with Escape handling
   const modalRef = useFocusTrap({
     isActive: isOpen,
@@ -60,9 +102,10 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
     restoreFocus: true,
   });
 
-  // Close on click outside
+  // Close on click outside (but not when ConfirmDialog is open)
   useEffect(() => {
     const handleClickOutside = (e: MouseEvent) => {
+      if (confirmDialogProps.isOpen) return;
       if (modalRef.current && !modalRef.current.contains(e.target as Node)) {
         onClose();
       }
@@ -72,13 +115,13 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
       document.addEventListener('mousedown', handleClickOutside);
       return () => document.removeEventListener('mousedown', handleClickOutside);
     }
-  }, [isOpen, onClose, modalRef]);
+  }, [isOpen, onClose, modalRef, confirmDialogProps.isOpen]);
 
   const handleCreate = useCallback(async (data: IdentityFormData) => {
     if (!client) return;
 
     try {
-      const newIdentity = await client.createIdentity(
+      await client.createIdentity(
         data.name,
         data.email,
         data.replyTo,
@@ -87,8 +130,7 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
         data.htmlSignature
       );
 
-      addIdentity(newIdentity);
+      await refreshIdentities();
-      syncIdentities();
       setIsCreating(false);
       toast.success(tNotif('identity_created'));
     } catch (error) {
@@ -96,7 +138,7 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
       toast.error(tNotif('identity_create_failed', { error: message }));
       throw error;
     }
-  }, [client, addIdentity, t, tNotif]);
+  }, [client, refreshIdentities, t, tNotif]);
 
   const handleUpdate = useCallback(async (identity: Identity, data: IdentityFormData) => {
     if (!client) return;
@@ -110,8 +152,7 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
         htmlSignature: data.htmlSignature,
       });
 
-      updateIdentityLocal(identity.id, data);
+      await refreshIdentities();
-      syncIdentities();
       setEditingId(null);
       toast.success(tNotif('identity_updated'));
     } catch (error) {
@@ -119,7 +160,7 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
       toast.error(tNotif('identity_update_failed', { error: message }));
       throw error;
     }
-  }, [client, updateIdentityLocal, t, tNotif]);
+  }, [client, refreshIdentities, t, tNotif]);
 
   const handleDelete = useCallback(async (identity: Identity) => {
     if (!client) return;
@@ -140,8 +181,7 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
 
     try {
       await client.deleteIdentity(identity.id);
-      removeIdentity(identity.id);
+      await refreshIdentities();
-      syncIdentities();
       toast.success(tNotif('identity_deleted'));
     } catch (error) {
       const message = error instanceof Error ? error.message : t('validation_errors.unknown_error');
@@ -149,7 +189,16 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
     } finally {
       setDeletingId(null);
     }
-  }, [client, removeIdentity, t, tNotif, confirmDialog]);
+  }, [client, refreshIdentities, t, tNotif, confirmDialog]);
+
+  const handleSetPrimary = useCallback((identity: Identity) => {
+    setPreferredPrimary(identity.id);
+    // Re-sort: move the preferred identity to the front
+    const reordered = [identity, ...identities.filter((id) => id.id !== identity.id)];
+    useIdentityStore.getState().setIdentities(reordered);
+    syncIdentities();
+    toast.success(tNotif('identity_set_primary'));
+  }, [identities, setPreferredPrimary, syncIdentities, tNotif]);
 
   if (!isOpen) return null;
 
@@ -264,6 +313,17 @@ export function IdentityManagerModal({ isOpen, onClose }: IdentityManagerModalPr
 
                       {/* Actions */}
                       <div className="flex items-center gap-2">
+                        {identities[0]?.id !== identity.id && identities.length > 1 && (
+                          <Button
+                            variant="ghost"
+                            size="sm"
+                            onClick={() => handleSetPrimary(identity)}
+                            disabled={!!editingId || isCreating}
+                            title={t('set_as_primary')}
+                          >
+                            <Star className="w-4 h-4" />
+                          </Button>
+                        )}
                         <Button
                           variant="ghost"
                           size="sm"

components/identity/sub-address-helper.tsx

@@ -135,7 +135,7 @@ export function SubAddressHelper({
         <div
           ref={popoverRef}
           className={cn(
-            'absolute top-full left-0 mt-1 z-50',
+            'absolute top-full right-0 mt-1 z-50',
             'bg-background border border-border rounded-lg shadow-lg',
             'w-80 p-4 animate-in fade-in zoom-in-95 duration-150'
           )}

components/layout/account-switcher.tsx

@@ -0,0 +1,273 @@
+"use client";
+
+import { useState, useRef, useEffect, useCallback } from "react";
+import { createPortal } from "react-dom";
+import { Check, Plus, LogOut, Star, ChevronDown, AlertCircle } from "lucide-react";
+import { useTranslations } from "next-intl";
+import { useAccountStore, type AccountEntry } from "@/stores/account-store";
+import { useAuthStore } from "@/stores/auth-store";
+import { getInitials, MAX_ACCOUNTS } from "@/lib/account-utils";
+import { cn } from "@/lib/utils";
+import { useRouter } from "@/i18n/navigation";
+
+interface AccountSwitcherProps {
+  /** "rail" = small avatar only (NavigationRail), "expanded" = avatar + name + email (Sidebar) */
+  variant?: "rail" | "expanded";
+  className?: string;
+}
+
+function AccountAvatar({ account, size = "sm" }: { account: AccountEntry; size?: "sm" | "md" }) {
+  const initials = getInitials(account.displayName || account.label, account.email || account.username);
+  const sizeClasses = size === "sm" ? "w-8 h-8 text-xs" : "w-9 h-9 text-sm";
+
+  return (
+    <div
+      className={cn("rounded-full flex items-center justify-center text-white font-medium flex-shrink-0", sizeClasses)}
+      style={{ backgroundColor: account.avatarColor }}
+      title={account.label}
+    >
+      {initials}
+    </div>
+  );
+}
+
+export function AccountSwitcher({ variant = "rail", className }: AccountSwitcherProps) {
+  const t = useTranslations("sidebar");
+  const router = useRouter();
+  const [open, setOpen] = useState(false);
+  const buttonRef = useRef<HTMLButtonElement>(null);
+  const popoverRef = useRef<HTMLDivElement>(null);
+  const [popoverStyle, setPopoverStyle] = useState<React.CSSProperties>({});
+
+  const accounts = useAccountStore((s) => s.accounts);
+  const activeAccountId = useAccountStore((s) => s.activeAccountId);
+  const setDefaultAccount = useAccountStore((s) => s.setDefaultAccount);
+  const activeAccount = accounts.find((a) => a.id === activeAccountId);
+  const switchAccount = useAuthStore((s) => s.switchAccount);
+  const logout = useAuthStore((s) => s.logout);
+  const logoutAll = useAuthStore((s) => s.logoutAll);
+  const primaryIdentity = useAuthStore((s) => s.primaryIdentity);
+
+  const updatePosition = useCallback(() => {
+    if (!buttonRef.current) return;
+    const rect = buttonRef.current.getBoundingClientRect();
+    if (variant === "rail") {
+      setPopoverStyle({
+        position: "fixed",
+        left: rect.right + 8,
+        bottom: Math.max(8, window.innerHeight - rect.bottom),
+      });
+    } else {
+      setPopoverStyle({
+        position: "fixed",
+        left: rect.left,
+        top: rect.bottom + 4,
+      });
+    }
+  }, [variant]);
+
+  useEffect(() => {
+    if (!open) return;
+    updatePosition();
+    const handleClickOutside = (e: MouseEvent) => {
+      if (
+        buttonRef.current?.contains(e.target as Node) ||
+        popoverRef.current?.contains(e.target as Node)
+      ) return;
+      setOpen(false);
+    };
+    const handleEscape = (e: KeyboardEvent) => {
+      if (e.key === "Escape") setOpen(false);
+    };
+    document.addEventListener("mousedown", handleClickOutside);
+    document.addEventListener("keydown", handleEscape);
+    return () => {
+      document.removeEventListener("mousedown", handleClickOutside);
+      document.removeEventListener("keydown", handleEscape);
+    };
+  }, [open, updatePosition]);
+
+  const handleSwitch = async (accountId: string) => {
+    if (accountId === activeAccountId) return;
+    setOpen(false);
+    await switchAccount(accountId);
+  };
+
+  const handleAddAccount = () => {
+    setOpen(false);
+    router.push(`/login?mode=add-account` as never);
+  };
+
+  const handleLogout = () => {
+    setOpen(false);
+    logout();
+    if (useAccountStore.getState().accounts.length === 0) {
+      router.push("/login" as never);
+    }
+  };
+
+  const handleLogoutAll = () => {
+    setOpen(false);
+    logoutAll();
+    router.push("/login" as never);
+  };
+
+  const handleSetDefault = (accountId: string) => {
+    setDefaultAccount(accountId);
+  };
+
+  // Display name for the active account
+  const displayName = primaryIdentity?.name || activeAccount?.displayName || activeAccount?.label || "";
+  const displayEmail = primaryIdentity?.email || activeAccount?.email || activeAccount?.username || "";
+
+  return (
+    <>
+      <button
+        ref={buttonRef}
+        onClick={() => setOpen(!open)}
+        className={cn(
+          "flex items-center gap-2 rounded-md transition-colors",
+          variant === "rail"
+            ? "justify-center w-10 h-10 hover:bg-muted"
+            : "w-full px-2 py-1.5 hover:bg-muted text-left min-w-0",
+          className
+        )}
+        title={variant === "rail" ? (displayName || displayEmail) : undefined}
+        aria-expanded={open}
+        aria-haspopup="true"
+      >
+        {activeAccount ? (
+          <>
+            <AccountAvatar account={activeAccount} size={variant === "rail" ? "sm" : "md"} />
+            {variant === "expanded" && (
+              <>
+                <div className="min-w-0 flex-1">
+                  <p className="text-sm font-medium text-foreground truncate">{displayName}</p>
+                  <p className="text-xs text-muted-foreground truncate">{displayEmail}</p>
+                </div>
+                <ChevronDown className={cn("w-3.5 h-3.5 text-muted-foreground flex-shrink-0 transition-transform", open && "rotate-180")} />
+              </>
+            )}
+          </>
+        ) : (
+          <div className={cn(
+            "rounded-full bg-muted flex items-center justify-center text-muted-foreground",
+            variant === "rail" ? "w-8 h-8 text-xs" : "w-9 h-9 text-sm"
+          )}>
+            ?
+          </div>
+        )}
+      </button>
+
+      {open && createPortal(
+        <div
+          ref={popoverRef}
+          style={popoverStyle}
+          className="w-72 rounded-lg border border-border bg-background text-foreground shadow-lg z-50 overflow-hidden"
+          role="menu"
+        >
+          {/* Account List */}
+          <div className="py-1 max-h-64 overflow-y-auto">
+            {accounts.map((account) => {
+              const isActive = account.id === activeAccountId;
+              return (
+                <button
+                  key={account.id}
+                  onClick={() => handleSwitch(account.id)}
+                  className={cn(
+                    "w-full flex items-start gap-3 px-3 py-2.5 text-left transition-colors",
+                    isActive ? "bg-accent/50" : "hover:bg-muted"
+                  )}
+                  role="menuitem"
+                  disabled={isActive}
+                >
+                  <div className="relative flex-shrink-0">
+                    <AccountAvatar account={account} size="md" />
+                    {isActive && (
+                      <div className="absolute -bottom-0.5 -right-0.5 w-4 h-4 rounded-full bg-primary flex items-center justify-center">
+                        <Check className="w-2.5 h-2.5 text-primary-foreground" />
+                      </div>
+                    )}
+                  </div>
+                  <div className="min-w-0 flex-1">
+                    <div className="flex items-center gap-1">
+                      <span className="text-sm font-medium truncate">
+                        {account.displayName || account.label}
+                      </span>
+                      {account.isDefault && (
+                        <Star className="w-3 h-3 text-amber-500 flex-shrink-0 fill-amber-500" />
+                      )}
+                    </div>
+                    <p className="text-xs text-muted-foreground truncate">
+                      {account.email || account.username}
+                    </p>
+                    <div className="flex items-center gap-1 mt-0.5">
+                      {account.hasError ? (
+                        <AlertCircle className="w-3 h-3 text-destructive" />
+                      ) : (
+                        <span className={cn(
+                          "w-1.5 h-1.5 rounded-full",
+                          account.isConnected ? "bg-green-500" : "bg-muted-foreground/40"
+                        )} />
+                      )}
+                      <span className="text-[10px] text-muted-foreground truncate">
+                        {new URL(account.serverUrl).hostname}
+                      </span>
+                    </div>
+                  </div>
+                </button>
+              );
+            })}
+          </div>
+
+          {/* Separator + Add Account */}
+          {accounts.length < MAX_ACCOUNTS && (
+            <div className="border-t border-border">
+              <button
+                onClick={handleAddAccount}
+                className="w-full flex items-center gap-2 px-3 py-2 text-sm text-foreground hover:bg-muted transition-colors"
+                role="menuitem"
+              >
+                <Plus className="w-4 h-4" />
+                {t("add_account")}
+              </button>
+            </div>
+          )}
+
+          {/* Separator + Actions */}
+          <div className="border-t border-border">
+            {activeAccount && !activeAccount.isDefault && accounts.length > 1 && (
+              <button
+                onClick={() => handleSetDefault(activeAccount.id)}
+                className="w-full flex items-center gap-2 px-3 py-2 text-sm text-foreground hover:bg-muted transition-colors"
+                role="menuitem"
+              >
+                <Star className="w-4 h-4" />
+                {t("set_as_default")}
+              </button>
+            )}
+            <button
+              onClick={handleLogout}
+              className="w-full flex items-center gap-2 px-3 py-2 text-sm text-foreground hover:bg-muted transition-colors"
+              role="menuitem"
+            >
+              <LogOut className="w-4 h-4" />
+              {t("sign_out_of", { account: displayEmail })}
+            </button>
+            {accounts.length > 1 && (
+              <button
+                onClick={handleLogoutAll}
+                className="w-full flex items-center gap-2 px-3 py-2 text-sm text-destructive hover:bg-muted transition-colors"
+                role="menuitem"
+              >
+                <LogOut className="w-4 h-4" />
+                {t("sign_out_all")}
+              </button>
+            )}
+          </div>
+        </div>,
+        document.body
+      )}
+    </>
+  );
+}

components/layout/icon-picker.tsx

@@ -0,0 +1,149 @@
+'use client';
+
+import { useState, useMemo, useRef, useEffect, useCallback } from 'react';
+import { useTranslations } from 'next-intl';
+import { icons as lucideIcons, type LucideIcon } from 'lucide-react';
+import { Search, X } from 'lucide-react';
+import { cn } from '@/lib/utils';
+import { Input } from '@/components/ui/input';
+
+// Curated list of commonly useful icons, organized by category
+const POPULAR_ICONS = [
+  // Communication
+  'Globe', 'Rss', 'Radio', 'Podcast', 'MessageCircle', 'MessageSquare', 'MessagesSquare',
+  'Phone', 'Video', 'Webcam', 'Headphones', 'Mic',
+  // Productivity
+  'FileText', 'FileSpreadsheet', 'Notebook', 'BookOpen', 'ClipboardList',
+  'ListTodo', 'CheckSquare', 'SquareKanban', 'Kanban', 'Trello',
+  'PenLine', 'Pencil', 'Edit', 'NotebookPen',
+  // Dev / Tech
+  'Code', 'Terminal', 'Braces', 'Bug', 'Database', 'Server', 'Cpu',
+  'HardDrive', 'Monitor', 'Laptop', 'Smartphone', 'Tablet',
+  'Wifi', 'Cloud', 'CloudDownload', 'CloudUpload',
+  // Social / People
+  'Users', 'UserPlus', 'UserCircle', 'Contact', 'PersonStanding',
+  'Heart', 'ThumbsUp', 'Star', 'Award', 'Trophy', 'Crown',
+  // Media
+  'Image', 'Camera', 'Film', 'Music', 'Play', 'Tv', 'Youtube', 'Clapperboard',
+  'Palette', 'Paintbrush', 'Brush',
+  // Navigation / Location
+  'Map', 'MapPin', 'Navigation', 'Compass', 'Home', 'Building', 'Building2',
+  'Landmark', 'Store', 'Warehouse',
+  // Finance
+  'DollarSign', 'Euro', 'CreditCard', 'Wallet', 'Receipt', 'PiggyBank',
+  'TrendingUp', 'BarChart', 'BarChart3', 'LineChart', 'PieChart',
+  // Security
+  'Shield', 'ShieldCheck', 'Lock', 'Unlock', 'Key', 'Fingerprint', 'Eye',
+  // Science / Health
+  'Beaker', 'Atom', 'Dna', 'Microscope', 'Stethoscope', 'HeartPulse', 'Pill',
+  'Syringe', 'Thermometer',
+  // Nature
+  'Sun', 'Moon', 'CloudSun', 'Snowflake', 'Zap', 'Flame',
+  'TreePine', 'Flower', 'Leaf', 'Mountain', 'Waves',
+  // Tools
+  'Wrench', 'Hammer', 'Scissors', 'Ruler', 'Magnet',
+  'Package', 'Gift', 'Box', 'Archive',
+  // Transport
+  'Car', 'Bike', 'Bus', 'Train', 'Plane', 'Ship', 'Rocket',
+  // Food
+  'Coffee', 'Wine', 'Beer', 'Pizza', 'Apple', 'Cake', 'CookingPot',
+  // Misc
+  'Gamepad2', 'Dice5', 'Puzzle', 'Sparkles', 'Wand2', 'Bot', 'BrainCircuit',
+  'Lightbulb', 'Bookmark', 'Flag', 'Bell', 'Clock', 'Timer',
+  'Link', 'ExternalLink', 'QrCode', 'Scan', 'LayoutGrid', 'Layers',
+  'Aperture', 'CircleDot', 'Target', 'Crosshair',
+];
+
+interface IconPickerProps {
+  value: string;
+  onChange: (iconName: string) => void;
+  className?: string;
+}
+
+export function IconPicker({ value, onChange, className }: IconPickerProps) {
+  const t = useTranslations('sidebar_apps');
+  const [search, setSearch] = useState('');
+  const [showAll, setShowAll] = useState(false);
+  const gridRef = useRef<HTMLDivElement>(null);
+
+  // Get all available icon names
+  const allIconNames = useMemo(() => {
+    return Object.keys(lucideIcons).filter(
+      k => /^[A-Z]/.test(k) && k !== 'createLucideIcon' && k !== 'Icon'
+    ).sort();
+  }, []);
+
+  const filteredIcons = useMemo(() => {
+    const source = showAll ? allIconNames : POPULAR_ICONS.filter(name => name in lucideIcons);
+    if (!search.trim()) return source;
+    const q = search.toLowerCase();
+    return source.filter(name => name.toLowerCase().includes(q));
+  }, [search, showAll, allIconNames]);
+
+  const renderIcon = useCallback((name: string) => {
+    const IconComponent = lucideIcons[name as keyof typeof lucideIcons] as LucideIcon | undefined;
+    if (!IconComponent) return null;
+    return <IconComponent className="w-5 h-5" />;
+  }, []);
+
+  return (
+    <div className={cn('space-y-2', className)}>
+      <div className="flex items-center gap-2">
+        <div className="relative flex-1">
+          <Search className="absolute left-2.5 top-1/2 -translate-y-1/2 w-3.5 h-3.5 text-muted-foreground" />
+          <Input
+            value={search}
+            onChange={(e) => setSearch(e.target.value)}
+            placeholder={t('search_icons')}
+            className="pl-8 h-8 text-xs"
+          />
+          {search && (
+            <button
+              onClick={() => setSearch('')}
+              className="absolute right-2 top-1/2 -translate-y-1/2 text-muted-foreground hover:text-foreground"
+            >
+              <X className="w-3 h-3" />
+            </button>
+          )}
+        </div>
+        <button
+          onClick={() => setShowAll(!showAll)}
+          className={cn(
+            'text-xs px-2 py-1 rounded-md border transition-colors whitespace-nowrap',
+            showAll
+              ? 'bg-primary/10 text-primary border-primary/30'
+              : 'bg-muted text-muted-foreground border-border hover:text-foreground'
+          )}
+        >
+          {showAll ? t('show_popular') : t('show_all')}
+        </button>
+      </div>
+      <div
+        ref={gridRef}
+        className="grid grid-cols-8 gap-1 max-h-[200px] overflow-y-auto p-1 border rounded-md bg-muted/30"
+      >
+        {filteredIcons.map(name => (
+          <button
+            key={name}
+            type="button"
+            onClick={() => onChange(name)}
+            title={name}
+            className={cn(
+              'flex items-center justify-center w-8 h-8 rounded-md transition-colors',
+              value === name
+                ? 'bg-primary text-primary-foreground'
+                : 'hover:bg-muted text-muted-foreground hover:text-foreground'
+            )}
+          >
+            {renderIcon(name)}
+          </button>
+        ))}
+        {filteredIcons.length === 0 && (
+          <p className="col-span-8 py-4 text-center text-xs text-muted-foreground">
+            {t('no_icons_found')}
+          </p>
+        )}
+      </div>
+    </div>
+  );
+}

components/layout/inline-app-view.tsx

@@ -0,0 +1,49 @@
+'use client';
+
+import { X } from 'lucide-react';
+import { cn } from '@/lib/utils';
+import type { InlineAppState } from '@/hooks/use-sidebar-apps';
+
+interface InlineAppViewProps {
+  apps: InlineAppState[];
+  activeAppId: string;
+  onClose: () => void;
+  className?: string;
+}
+
+export function InlineAppView({ apps, activeAppId, onClose, className }: InlineAppViewProps) {
+  const activeApp = apps.find((a) => a.id === activeAppId);
+
+  return (
+    <div className={cn('flex flex-col h-full bg-background', className)}>
+      {/* Header bar */}
+      <div className="flex items-center justify-between px-4 py-2 border-b border-border bg-secondary/50 flex-shrink-0">
+        <h3 className="text-sm font-medium truncate">{activeApp?.name}</h3>
+        <button
+          onClick={onClose}
+          className="p-1 rounded-md hover:bg-muted transition-colors text-muted-foreground hover:text-foreground"
+          aria-label="Close"
+        >
+          <X className="w-4 h-4" />
+        </button>
+      </div>
+      {/* Iframes - active one visible, rest hidden but alive */}
+      <div className="flex-1 relative">
+        {apps.map((app) => (
+          <iframe
+            key={app.id}
+            src={app.url}
+            title={app.name}
+            className={cn(
+              'absolute inset-0 w-full h-full border-0',
+              app.id !== activeAppId && 'hidden'
+            )}
+            sandbox="allow-scripts allow-same-origin allow-forms allow-popups allow-popups-to-escape-sandbox"
+            referrerPolicy="no-referrer"
+            loading="lazy"
+          />
+        ))}
+      </div>
+    </div>
+  );
+}

components/layout/navigation-rail.tsx

@@ -2,12 +2,15 @@
 
 import { useState, useRef, useEffect, useCallback } from "react";
 import { createPortal } from "react-dom";
-import { Mail, Calendar, BookUser, HardDrive, Settings, LogOut, Keyboard } from "lucide-react";
+import { Mail, Calendar, BookUser, HardDrive, Settings, LogOut, Keyboard, Plus } from "lucide-react";
+import { AccountSwitcher } from "./account-switcher";
+import { icons as lucideIcons, type LucideIcon } from "lucide-react";
 import { usePathname, Link } from "@/i18n/navigation";
 import { useTranslations } from "next-intl";
 import { useCalendarStore } from "@/stores/calendar-store";
 import { useEmailStore } from "@/stores/email-store";
 import { useWebDAVStore } from "@/stores/webdav-store";
+import { useSettingsStore } from "@/stores/settings-store";
 import { cn, formatFileSize } from "@/lib/utils";
 
 interface NavItem {
@@ -27,6 +30,10 @@ interface NavigationRailProps {
   isPushConnected?: boolean;
   onLogout?: () => void;
   onShowShortcuts?: () => void;
+  onManageApps?: () => void;
+  onInlineApp?: (appId: string, url: string, name: string) => void;
+  onCloseInlineApp?: () => void;
+  activeAppId?: string | null;
 }
 
 function StorageQuotaCircle({ quota, usagePercent }: { quota: { used: number; total: number }; usagePercent: number }) {
@@ -138,12 +145,17 @@ export function NavigationRail({
   isPushConnected,
   onLogout,
   onShowShortcuts,
+  onManageApps,
+  onInlineApp,
+  onCloseInlineApp,
+  activeAppId,
 }: NavigationRailProps) {
   const t = useTranslations("sidebar");
   const pathname = usePathname();
   const { supportsCalendar } = useCalendarStore();
   const { mailboxes } = useEmailStore();
   const { supportsWebDAV } = useWebDAVStore();
+  const sidebarApps = useSettingsStore((s) => s.sidebarApps);
   const inboxUnread = mailboxes.find(m => m.role === "inbox")?.unreadEmails || 0;
 
   const navItems: NavItem[] = [
@@ -151,12 +163,14 @@ export function NavigationRail({
     { id: "calendar", icon: Calendar, labelKey: "calendar", href: "/calendar", hidden: !supportsCalendar },
     { id: "contacts", icon: BookUser, labelKey: "contacts", href: "/contacts" },
     { id: "files", icon: HardDrive, labelKey: "files", href: "/files", hidden: supportsWebDAV === false },
-    { id: "settings", icon: Settings, labelKey: "settings", href: "/settings" },
   ];
 
+  const isSettingsActive = !activeAppId && pathname.startsWith("/settings");
+
   const visibleItems = navItems.filter((item) => !item.hidden);
 
   const getIsActive = (href: string) => {
+    if (activeAppId) return false;
     if (href === "/") {
       return pathname === "/" || pathname === "";
     }
@@ -177,6 +191,7 @@ export function NavigationRail({
             <Link
               key={item.id}
               href={item.href}
+              onClick={activeAppId ? () => onCloseInlineApp?.() : undefined}
               className={cn(
                 "flex flex-col items-center justify-center gap-1 py-2 px-3 min-w-[64px] min-h-[44px]",
                 "transition-colors duration-150",
@@ -201,6 +216,52 @@ export function NavigationRail({
             </Link>
           );
         })}
+
+        {/* Custom sidebar apps */}
+        {sidebarApps.map((app) => {
+          const AppIcon = lucideIcons[app.icon as keyof typeof lucideIcons] as LucideIcon | undefined;
+          const isActive = activeAppId === app.id;
+          return (
+            <button
+              key={app.id}
+              onClick={() => {
+                if (isActive) {
+                  onCloseInlineApp?.();
+                } else if (app.openMode === 'tab') {
+                  window.open(app.url, '_blank', 'noopener,noreferrer');
+                } else {
+                  onInlineApp?.(app.id, app.url, app.name);
+                }
+              }}
+              className={cn(
+                "flex flex-col items-center justify-center gap-1 py-2 px-3 min-w-[64px] min-h-[44px]",
+                "transition-colors duration-150",
+                isActive
+                  ? "text-primary"
+                  : "text-muted-foreground hover:text-foreground"
+              )}
+            >
+              <div className="relative">
+                {AppIcon ? <AppIcon className="w-5 h-5" /> : null}
+                {isActive && (
+                  <span className="absolute -bottom-1 left-1/2 -translate-x-1/2 w-4 h-0.5 rounded-full bg-primary" />
+                )}
+              </div>
+              <span className="text-[10px] font-medium leading-tight truncate max-w-[64px]">{app.name}</span>
+            </button>
+          );
+        })}
+
+        {/* Manage apps button */}
+        {onManageApps && (
+          <button
+            onClick={onManageApps}
+            className="flex flex-col items-center justify-center gap-1 py-2 px-3 min-w-[64px] min-h-[44px] transition-colors duration-150 text-muted-foreground hover:text-foreground"
+          >
+            <Plus className="w-5 h-5" />
+            <span className="text-[10px] font-medium leading-tight">{t("add_app")}</span>
+          </button>
+        )}
       </nav>
     );
   }
@@ -230,6 +291,7 @@ export function NavigationRail({
             <Link
               key={item.id}
               href={item.href}
+              onClick={activeAppId ? () => onCloseInlineApp?.() : undefined}
               className={cn(
                 "relative flex items-center gap-2.5 rounded-md transition-colors duration-150",
                 collapsed
@@ -257,13 +319,90 @@ export function NavigationRail({
             </Link>
           );
         })}
+
+        {/* Custom sidebar apps */}
+        {sidebarApps.length > 0 && (
+          <div
+            className={cn(
+              "border-t",
+              collapsed ? "w-8 mx-auto my-1 pt-1" : "mx-2 my-0.5 pt-0.5"
+            )}
+            style={{ borderColor: 'rgba(128, 128, 128, 0.3)' }}
+          />
+        )}
+        {sidebarApps.map((app) => {
+          const AppIcon = lucideIcons[app.icon as keyof typeof lucideIcons] as LucideIcon | undefined;
+          const isActive = activeAppId === app.id;
+          return (
+            <button
+              key={app.id}
+              onClick={() => {
+                if (isActive) {
+                  onCloseInlineApp?.();
+                } else if (app.openMode === 'tab') {
+                  window.open(app.url, '_blank', 'noopener,noreferrer');
+                } else {
+                  onInlineApp?.(app.id, app.url, app.name);
+                }
+              }}
+              className={cn(
+                "relative flex items-center gap-2.5 rounded-md transition-colors duration-150",
+                collapsed
+                  ? "justify-center w-10 h-10"
+                  : "px-2.5 text-sm",
+                "max-lg:min-h-[44px]",
+                isActive
+                  ? "bg-primary/10 text-primary font-medium"
+                  : "text-muted-foreground hover:bg-muted hover:text-foreground"
+              )}
+              title={collapsed ? app.name : undefined}
+              style={collapsed ? undefined : { paddingBlock: 'var(--density-sidebar-py)' }}
+            >
+              {AppIcon ? <AppIcon className={cn("w-[18px] h-[18px] flex-shrink-0", isActive && "text-primary")} /> : null}
+              {!collapsed && <span className="truncate">{app.name}</span>}
+            </button>
+          );
+        })}
+
+        {/* Manage apps button */}
+        {onManageApps && (
+          <button
+            onClick={onManageApps}
+            className={cn(
+              "relative flex items-center gap-2.5 rounded-md transition-colors duration-150",
+              collapsed
+                ? "justify-center w-10 h-10"
+                : "px-2.5 text-sm",
+              "max-lg:min-h-[44px]",
+              "text-muted-foreground hover:bg-muted hover:text-foreground"
+            )}
+            title={collapsed ? t("add_app") : undefined}
+            style={collapsed ? undefined : { paddingBlock: 'var(--density-sidebar-py)' }}
+          >
+            <Plus className="w-[18px] h-[18px] flex-shrink-0" />
+            {!collapsed && <span className="truncate">{t("add_app")}</span>}
+          </button>
+        )}
       </nav>
 
-      {/* Footer: Storage Quota + Sign Out + Push Status */}
+      {/* Footer: Settings + Help + Storage Quota + Sign Out + Push Status */}
-      <div className="mt-auto flex flex-col items-center gap-2 pb-3 px-1 border-t border-border pt-2">
+      <div className="mt-auto flex flex-col items-center gap-2 pb-3 px-1">
-        {quota && quota.total > 0 && (
+        <Link
-          <StorageQuotaCircle quota={quota} usagePercent={quotaUsagePercent} />
+          href="/settings"
-        )}
+          onClick={activeAppId ? () => onCloseInlineApp?.() : undefined}
+          className={cn(
+            "flex items-center justify-center w-10 h-10 rounded-md transition-colors",
+            isSettingsActive
+              ? "bg-primary/10 text-primary"
+              : "text-muted-foreground hover:text-foreground hover:bg-muted"
+          )}
+          title={t("settings")}
+          aria-current={isSettingsActive ? "page" : undefined}
+        >
+          <Settings className="w-[18px] h-[18px]" />
+        </Link>
+
+        <div className="w-8 border-t" style={{ borderColor: 'rgba(128, 128, 128, 0.3)' }} />
 
         {onShowShortcuts && (
           <button
@@ -275,6 +414,10 @@ export function NavigationRail({
           </button>
         )}
 
+        {quota && quota.total > 0 && (
+          <StorageQuotaCircle quota={quota} usagePercent={quotaUsagePercent} />
+        )}
+
         {isPushConnected != null && (
           <span
             className="relative group"
@@ -290,13 +433,7 @@ export function NavigationRail({
         )}
 
         {onLogout && (
-          <button
+          <AccountSwitcher variant="rail" />
-            onClick={onLogout}
-            className="flex items-center justify-center w-10 h-10 rounded-md text-muted-foreground hover:text-foreground hover:bg-muted transition-colors"
-            title={t("sign_out")}
-          >
-            <LogOut className="w-[18px] h-[18px]" />
-          </button>
         )}
       </div>
     </div>

components/layout/sidebar-apps-modal.tsx

@@ -0,0 +1,355 @@
+'use client';
+
+import { useState, useCallback } from 'react';
+import { useTranslations } from 'next-intl';
+import { X, Plus, Pencil, Trash2, GripVertical, ExternalLink, PanelRight } from 'lucide-react';
+import { icons as lucideIcons, type LucideIcon } from 'lucide-react';
+import { cn } from '@/lib/utils';
+import { Button } from '@/components/ui/button';
+import { Input } from '@/components/ui/input';
+import { IconPicker } from './icon-picker';
+import { useSettingsStore, type SidebarApp } from '@/stores/settings-store';
+import { useFocusTrap } from '@/hooks/use-focus-trap';
+import { useConfirmDialog } from '@/hooks/use-confirm-dialog';
+import { ConfirmDialog } from '@/components/ui/confirm-dialog';
+
+interface SidebarAppFormData {
+  name: string;
+  url: string;
+  icon: string;
+  openMode: 'tab' | 'inline';
+}
+
+function SidebarAppForm({
+  app,
+  onSave,
+  onCancel,
+}: {
+  app?: SidebarApp;
+  onSave: (data: SidebarAppFormData) => void;
+  onCancel: () => void;
+}) {
+  const t = useTranslations('sidebar_apps');
+  const isEditing = !!app;
+
+  const [formData, setFormData] = useState<SidebarAppFormData>({
+    name: app?.name || '',
+    url: app?.url || '',
+    icon: app?.icon || 'Globe',
+    openMode: app?.openMode || 'tab',
+  });
+  const [errors, setErrors] = useState<Record<string, string>>({});
+
+  const validate = (): boolean => {
+    const newErrors: Record<string, string> = {};
+    if (!formData.name.trim()) {
+      newErrors.name = t('name_required');
+    }
+    if (!formData.url.trim()) {
+      newErrors.url = t('url_required');
+    } else {
+      try {
+        const parsed = new URL(formData.url);
+        if (!['http:', 'https:'].includes(parsed.protocol)) {
+          newErrors.url = t('url_invalid');
+        }
+      } catch {
+        newErrors.url = t('url_invalid');
+      }
+    }
+    if (!formData.icon) {
+      newErrors.icon = t('icon_required');
+    }
+    setErrors(newErrors);
+    return Object.keys(newErrors).length === 0;
+  };
+
+  const handleSubmit = (e: React.FormEvent) => {
+    e.preventDefault();
+    if (!validate()) return;
+    onSave(formData);
+  };
+
+  const SelectedIcon = formData.icon
+    ? (lucideIcons[formData.icon as keyof typeof lucideIcons] as LucideIcon | undefined)
+    : null;
+
+  return (
+    <form onSubmit={handleSubmit} className="space-y-4">
+      {/* Name */}
+      <div>
+        <label htmlFor="app-name" className="block text-sm font-medium mb-1">
+          {t('name_label')} <span className="text-destructive">*</span>
+        </label>
+        <Input
+          id="app-name"
+          type="text"
+          maxLength={50}
+          value={formData.name}
+          onChange={(e) => setFormData({ ...formData, name: e.target.value })}
+          placeholder={t('name_placeholder')}
+          className={errors.name ? 'border-destructive' : ''}
+        />
+        {errors.name && (
+          <p className="text-sm text-destructive mt-1">{errors.name}</p>
+        )}
+      </div>
+
+      {/* URL */}
+      <div>
+        <label htmlFor="app-url" className="block text-sm font-medium mb-1">
+          {t('url_label')} <span className="text-destructive">*</span>
+        </label>
+        <Input
+          id="app-url"
+          type="url"
+          maxLength={2048}
+          value={formData.url}
+          onChange={(e) => setFormData({ ...formData, url: e.target.value })}
+          placeholder="https://example.com"
+          className={errors.url ? 'border-destructive' : ''}
+        />
+        {errors.url && (
+          <p className="text-sm text-destructive mt-1">{errors.url}</p>
+        )}
+      </div>
+
+      {/* Open Mode */}
+      <div>
+        <label className="block text-sm font-medium mb-2">{t('open_mode_label')}</label>
+        <div className="flex gap-2">
+          <button
+            type="button"
+            onClick={() => setFormData({ ...formData, openMode: 'tab' })}
+            className={cn(
+              'flex items-center gap-2 px-3 py-2 rounded-md border text-sm transition-colors flex-1',
+              formData.openMode === 'tab'
+                ? 'bg-primary/10 border-primary/30 text-primary'
+                : 'border-border text-muted-foreground hover:text-foreground hover:border-muted-foreground'
+            )}
+          >
+            <ExternalLink className="w-4 h-4" />
+            {t('open_new_tab')}
+          </button>
+          <button
+            type="button"
+            onClick={() => setFormData({ ...formData, openMode: 'inline' })}
+            className={cn(
+              'flex items-center gap-2 px-3 py-2 rounded-md border text-sm transition-colors flex-1',
+              formData.openMode === 'inline'
+                ? 'bg-primary/10 border-primary/30 text-primary'
+                : 'border-border text-muted-foreground hover:text-foreground hover:border-muted-foreground'
+            )}
+          >
+            <PanelRight className="w-4 h-4" />
+            {t('open_inline')}
+          </button>
+        </div>
+      </div>
+
+      {/* Icon Picker */}
+      <div>
+        <label className="block text-sm font-medium mb-2">
+          {t('icon_label')} <span className="text-destructive">*</span>
+          {SelectedIcon && (
+            <span className="inline-flex items-center gap-1.5 ml-2 text-muted-foreground font-normal">
+              — <SelectedIcon className="w-4 h-4" /> {formData.icon}
+            </span>
+          )}
+        </label>
+        <IconPicker
+          value={formData.icon}
+          onChange={(icon) => setFormData({ ...formData, icon })}
+        />
+        {errors.icon && (
+          <p className="text-sm text-destructive mt-1">{errors.icon}</p>
+        )}
+      </div>
+
+      {/* Actions */}
+      <div className="flex justify-end gap-2 pt-2">
+        <Button type="button" variant="outline" onClick={onCancel}>
+          {t('cancel')}
+        </Button>
+        <Button type="submit">
+          {isEditing ? t('update') : t('add')}
+        </Button>
+      </div>
+    </form>
+  );
+}
+
+interface SidebarAppsModalProps {
+  isOpen: boolean;
+  onClose: () => void;
+}
+
+export function SidebarAppsModal({ isOpen, onClose }: SidebarAppsModalProps) {
+  const t = useTranslations('sidebar_apps');
+  const { sidebarApps, addSidebarApp, updateSidebarApp, removeSidebarApp } = useSettingsStore();
+  const [editingId, setEditingId] = useState<string | null>(null);
+  const [isCreating, setIsCreating] = useState(false);
+  const { dialogProps: confirmDialogProps, confirm: confirmDialog } = useConfirmDialog();
+
+  const modalRef = useFocusTrap({
+    isActive: isOpen,
+    onEscape: () => {
+      if (isCreating || editingId) {
+        setIsCreating(false);
+        setEditingId(null);
+      } else {
+        onClose();
+      }
+    },
+    restoreFocus: true,
+  });
+
+  const handleCreate = useCallback((data: SidebarAppFormData) => {
+    const id = `app-${Date.now()}-${Math.random().toString(36).slice(2, 7)}`;
+    addSidebarApp({ id, ...data });
+    setIsCreating(false);
+  }, [addSidebarApp]);
+
+  const handleUpdate = useCallback((id: string, data: SidebarAppFormData) => {
+    updateSidebarApp(id, data);
+    setEditingId(null);
+  }, [updateSidebarApp]);
+
+  const handleDelete = useCallback(async (app: SidebarApp) => {
+    const confirmed = await confirmDialog({
+      title: t('delete_confirm_title'),
+      message: t('delete_confirm', { name: app.name }),
+      confirmText: t('delete'),
+      variant: 'destructive',
+    });
+    if (!confirmed) return;
+    removeSidebarApp(app.id);
+  }, [removeSidebarApp, confirmDialog, t]);
+
+  if (!isOpen) return null;
+
+  return (
+    <div className="fixed inset-0 bg-black/50 backdrop-blur-[1px] flex items-center justify-center z-50 p-4 animate-in fade-in duration-150">
+      <div
+        ref={modalRef}
+        role="dialog"
+        aria-modal="true"
+        aria-labelledby="sidebar-apps-modal-title"
+        className={cn(
+          'bg-background border border-border rounded-lg shadow-xl',
+          'w-full max-w-2xl max-h-[90vh] overflow-hidden',
+          'animate-in zoom-in-95 duration-200'
+        )}
+      >
+        {/* Header */}
+        <div className="flex items-center justify-between px-6 py-4 border-b border-border">
+          <h2 id="sidebar-apps-modal-title" className="text-lg font-semibold text-foreground">
+            {t('modal_title')}
+          </h2>
+          <button
+            onClick={onClose}
+            className="p-1.5 rounded-md hover:bg-muted transition-colors text-muted-foreground hover:text-foreground"
+          >
+            <X className="w-5 h-5" />
+          </button>
+        </div>
+
+        {/* Content */}
+        <div className="p-6 overflow-y-auto max-h-[calc(90vh-80px)]">
+          {/* Create form */}
+          {isCreating && (
+            <div className="mb-6 p-4 border border-border rounded-lg bg-muted/30">
+              <h3 className="text-sm font-semibold mb-4">{t('add_new')}</h3>
+              <SidebarAppForm
+                onSave={handleCreate}
+                onCancel={() => setIsCreating(false)}
+              />
+            </div>
+          )}
+
+          {/* Add button */}
+          {!isCreating && !editingId && (
+            <Button
+              onClick={() => setIsCreating(true)}
+              className="mb-6 w-full sm:w-auto"
+            >
+              <Plus className="w-4 h-4 mr-2" />
+              {t('add_new')}
+            </Button>
+          )}
+
+          {/* Apps list */}
+          <div className="space-y-3">
+            {sidebarApps.map((app) => {
+              const AppIcon = lucideIcons[app.icon as keyof typeof lucideIcons] as LucideIcon | undefined;
+
+              if (editingId === app.id) {
+                return (
+                  <div key={app.id} className="p-4 border border-border rounded-lg bg-muted/30">
+                    <h3 className="text-sm font-semibold mb-4">{t('edit_app')}</h3>
+                    <SidebarAppForm
+                      app={app}
+                      onSave={(data) => handleUpdate(app.id, data)}
+                      onCancel={() => setEditingId(null)}
+                    />
+                  </div>
+                );
+              }
+
+              return (
+                <div
+                  key={app.id}
+                  className="flex items-center gap-3 p-3 border border-border rounded-lg"
+                >
+                  <div className="flex items-center justify-center w-9 h-9 rounded-md bg-muted">
+                    {AppIcon ? <AppIcon className="w-5 h-5 text-muted-foreground" /> : null}
+                  </div>
+                  <div className="flex-1 min-w-0">
+                    <p className="font-medium text-sm truncate">{app.name}</p>
+                    <p className="text-xs text-muted-foreground truncate">{app.url}</p>
+                  </div>
+                  <span className={cn(
+                    'text-[10px] px-1.5 py-0.5 rounded-full font-medium',
+                    app.openMode === 'inline'
+                      ? 'bg-blue-100 text-blue-700 dark:bg-blue-950/40 dark:text-blue-400'
+                      : 'bg-gray-100 text-gray-700 dark:bg-gray-800 dark:text-gray-400'
+                  )}>
+                    {app.openMode === 'inline' ? t('inline_badge') : t('tab_badge')}
+                  </span>
+                  <div className="flex items-center gap-1">
+                    <Button
+                      variant="ghost"
+                      size="sm"
+                      onClick={() => setEditingId(app.id)}
+                      disabled={!!editingId || isCreating}
+                    >
+                      <Pencil className="w-4 h-4" />
+                    </Button>
+                    <Button
+                      variant="ghost"
+                      size="sm"
+                      onClick={() => handleDelete(app)}
+                      disabled={!!editingId || isCreating}
+                    >
+                      <Trash2 className="w-4 h-4 text-destructive" />
+                    </Button>
+                  </div>
+                </div>
+              );
+            })}
+
+            {sidebarApps.length === 0 && !isCreating && (
+              <div className="text-center py-12 text-muted-foreground">
+                <Plus className="w-12 h-12 mx-auto mb-3 opacity-50" />
+                <p className="text-sm">{t('no_apps')}</p>
+                <p className="text-xs mt-1">{t('no_apps_hint')}</p>
+              </div>
+            )}
+          </div>
+        </div>
+      </div>
+
+      <ConfirmDialog {...confirmDialogProps} />
+    </div>
+  );
+}

components/layout/sidebar.tsx

@@ -37,6 +37,9 @@ import { useSettingsStore, KEYWORD_PALETTE, KeywordDefinition } from "@/stores/s
 import { useEmailStore } from "@/stores/email-store";
 import { toast } from "@/stores/toast-store";
 import { debug } from "@/lib/debug";
+import { useConfig } from "@/hooks/use-config";
+import { useThemeStore } from "@/stores/theme-store";
+import { AccountSwitcher } from "./account-switcher";
 
 interface SidebarProps {
   mailboxes: Mailbox[];
@@ -361,6 +364,8 @@ export function Sidebar({
 }: SidebarProps) {
   const { sidebarCollapsed: isCollapsed, toggleSidebarCollapsed } = useUIStore();
   const { primaryIdentity } = useAuthStore();
+  const { appLogoLightUrl, appLogoDarkUrl } = useConfig();
+  const resolvedTheme = useThemeStore((s) => s.resolvedTheme);
   const [expandedFolders, setExpandedFolders] = useState<Set<string>>(new Set());
   const [tagsExpanded, setTagsExpanded] = useState(() => {
     try {
@@ -460,6 +465,17 @@ export function Sidebar({
           <X className="w-5 h-5" />
         </Button>
 
+        {(() => {
+          const logoUrl = resolvedTheme === 'dark' ? (appLogoDarkUrl || appLogoLightUrl) : (appLogoLightUrl || appLogoDarkUrl);
+          return logoUrl ? (
+            <img
+              src={logoUrl}
+              alt=""
+              className={cn("object-contain flex-shrink-0", isCollapsed ? "w-6 h-6" : "w-6 h-6")}
+            />
+          ) : null;
+        })()}
+
         <Button
           variant="ghost"
           size="icon"
@@ -470,15 +486,8 @@ export function Sidebar({
           {isCollapsed ? <ChevronsRight className="w-4 h-4" /> : <ChevronsLeft className="w-4 h-4" />}
         </Button>
 
-        {!isCollapsed && primaryIdentity && (
+        {!isCollapsed && (
-          <div className="min-w-0">
+          <AccountSwitcher variant="expanded" className="flex-1" />
-            <p className="text-sm font-medium text-foreground truncate" title={primaryIdentity.name}>
-              {primaryIdentity.name}
-            </p>
-            <p className="text-xs text-muted-foreground truncate" title={primaryIdentity.email}>
-              {primaryIdentity.email}
-            </p>
-          </div>
         )}
       </div>
 

components/settings/calendar-management-settings.tsx

@@ -7,9 +7,10 @@ import { useAuthStore } from '@/stores/auth-store';
 import { toast } from '@/stores/toast-store';
 import { SettingsSection } from './settings-section';
 import { Plus, Pencil, Trash2, Check, X, Calendar as CalendarIcon, Copy, Link, Upload, Globe, RefreshCw, Eraser } from 'lucide-react';
-import { cn } from '@/lib/utils';
+import { cn, formatDateTime } from '@/lib/utils';
 import { ICalImportModal } from '@/components/calendar/ical-import-modal';
 import { ICalSubscriptionModal } from '@/components/calendar/ical-subscription-modal';
+import { useSettingsStore } from '@/stores/settings-store';
 
 const CALENDAR_COLORS = [
   "#3b82f6", // blue
@@ -152,6 +153,9 @@ export function CalendarManagementSettings() {
   const { client, serverUrl, username } = useAuthStore();
   const { calendars, updateCalendar, createCalendar, removeCalendar, clearCalendarEvents, fetchCalendars, icalSubscriptions, removeICalSubscription, refreshICalSubscription, isSubscriptionCalendar } = useCalendarStore();
 
+  const [discoveredCalDavUrls, setDiscoveredCalDavUrls] = useState<Record<string, string | null>>({});
+  const [wellKnownCalDavUrl, setWellKnownCalDavUrl] = useState<string | null>(null);
+
   const [isCreating, setIsCreating] = useState(false);
   const [editingId, setEditingId] = useState<string | null>(null);
   const [deletingId, setDeletingId] = useState<string | null>(null);
@@ -164,6 +168,7 @@ export function CalendarManagementSettings() {
   const [refreshingSubId, setRefreshingSubId] = useState<string | null>(null);
   const tImport = useTranslations('calendar.import');
   const tSub = useTranslations('calendar.subscription');
+  const timeFormat = useSettingsStore((s) => s.timeFormat);
   const colorPickerRef = useRef<HTMLDivElement>(null);
 
   // Load calendars if not yet loaded
@@ -173,6 +178,60 @@ export function CalendarManagementSettings() {
     }
   }, [client, calendars.length, fetchCalendars]);
 
+  useEffect(() => {
+    if (!client || !serverUrl || !username) {
+      setDiscoveredCalDavUrls({});
+      setWellKnownCalDavUrl(null);
+      return;
+    }
+
+    const primaryKey = username;
+    const accounts = new Map<string, string[]>();
+    accounts.set(primaryKey, [username]);
+
+    for (const calendar of calendars) {
+      if (!calendar.isShared) continue;
+      const key = calendar.accountId || calendar.accountName || calendar.id;
+      const candidates = accounts.get(key) || [];
+      if (calendar.accountId) candidates.push(calendar.accountId);
+      if (calendar.accountName) candidates.push(calendar.accountName);
+      accounts.set(key, candidates);
+    }
+
+    const controller = new AbortController();
+
+    fetch('/api/caldav/discover', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({
+        accounts: Array.from(accounts.entries()).map(([key, candidates]) => ({ key, candidates })),
+      }),
+      signal: controller.signal,
+    })
+      .then(async (response) => {
+        if (!response.ok) throw new Error(`CalDAV discovery failed: ${response.status}`);
+        return response.json() as Promise<{
+          wellKnownUrl?: string;
+          accounts?: Record<string, { url: string | null }>;
+        }>;
+      })
+      .then((payload) => {
+        setWellKnownCalDavUrl(payload.wellKnownUrl || null);
+        const next: Record<string, string | null> = {};
+        for (const [key, value] of Object.entries(payload.accounts || {})) {
+          next[key] = value?.url || null;
+        }
+        setDiscoveredCalDavUrls(next);
+      })
+      .catch(() => {
+        const fallbackWellKnown = new URL('/.well-known/caldav', serverUrl).toString();
+        setDiscoveredCalDavUrls({});
+        setWellKnownCalDavUrl(fallbackWellKnown);
+      });
+
+    return () => controller.abort();
+  }, [client, calendars, serverUrl, username]);
+
   const handleRefreshSubscription = async (subId: string) => {
     if (!client) return;
     setRefreshingSubId(subId);
@@ -293,8 +352,10 @@ export function CalendarManagementSettings() {
 
   const buildCalDavUrl = (calendarId: string) => {
     if (!serverUrl || !username) return null;
-    const base = serverUrl.replace(/\/$/, '');
+    const calendar = calendars.find((entry) => entry.id === calendarId);
-    return `${base}/dav/calendars/user/${encodeURIComponent(username)}/${encodeURIComponent(calendarId)}/`;
+    if (!calendar) return null;
+    const accountKey = calendar.isShared ? (calendar.accountId || calendar.accountName || calendar.id) : username;
+    return discoveredCalDavUrls[accountKey] || wellKnownCalDavUrl;
   };
 
   const handleCopyUrl = async (url: string) => {
@@ -563,7 +624,7 @@ export function CalendarManagementSettings() {
                   </span>
                   {sub.lastRefreshed && (
                     <span className="text-xs text-muted-foreground">
-                      {tSub('last_refreshed', { time: new Date(sub.lastRefreshed).toLocaleString() })}
+                      {tSub('last_refreshed', { time: formatDateTime(sub.lastRefreshed, timeFormat, { month: 'short', day: 'numeric', year: 'numeric' }) })}
                     </span>
                   )}
                 </div>

components/settings/email-settings.tsx

@@ -3,13 +3,18 @@
 import { useState } from 'react';
 import { useTranslations } from 'next-intl';
 import { useSettingsStore } from '@/stores/settings-store';
+import type { ArchiveMode } from '@/stores/settings-store';
+import { useAuthStore } from '@/stores/auth-store';
+import { useEmailStore } from '@/stores/email-store';
 import { SettingsSection, SettingItem, Select, ToggleSwitch } from './settings-section';
 import { TrustedSendersModal } from '@/components/trusted-senders-modal';
-import { ChevronRight, AlertTriangle } from 'lucide-react';
+import { ChevronRight, AlertTriangle, FolderSync, Loader2 } from 'lucide-react';
 
 export function EmailSettings() {
   const t = useTranslations('settings.email_behavior');
   const [showTrustedModal, setShowTrustedModal] = useState(false);
+  const [isReorganizing, setIsReorganizing] = useState(false);
+  const [reorganizeResult, setReorganizeResult] = useState<string | null>(null);
 
   const {
     markAsReadDelay,
@@ -19,6 +24,8 @@ export function EmailSettings() {
     emailsPerPage,
     externalContentPolicy,
     mailAttachmentAction,
+    emailAlwaysLightMode,
+    archiveMode,
     trustedSenders,
     updateSetting,
   } = useSettingsStore();
@@ -31,6 +38,69 @@ export function EmailSettings() {
     return t('trusted_senders.count_other', { count });
   };
 
+  const handleReorganizeArchive = async () => {
+    const { client } = useAuthStore.getState();
+    const { mailboxes, fetchMailboxes } = useEmailStore.getState();
+    if (!client) return;
+
+    const archiveMailbox = mailboxes.find(m => m.role === 'archive' || m.name.toLowerCase() === 'archive');
+    if (!archiveMailbox) return;
+
+    setIsReorganizing(true);
+    setReorganizeResult(null);
+
+    try {
+      const archiveId = archiveMailbox.originalId || archiveMailbox.id;
+
+      // Fetch all emails in the root archive mailbox
+      const emails = await client.getEmailsInMailbox(archiveId);
+      let movedCount = 0;
+
+      for (const email of emails) {
+        const emailDate = new Date(email.receivedAt);
+        const year = emailDate.getFullYear().toString();
+        const month = (emailDate.getMonth() + 1).toString().padStart(2, '0');
+
+        // Re-read mailboxes from store each iteration in case new ones were created
+        let currentMailboxes = useEmailStore.getState().mailboxes;
+
+        // Find or create year subfolder
+        let yearMailbox = currentMailboxes.find(
+          m => m.name === year && m.parentId === archiveId
+        );
+        if (!yearMailbox) {
+          yearMailbox = await client.createMailbox(year, archiveId);
+          await fetchMailboxes(client);
+          currentMailboxes = useEmailStore.getState().mailboxes;
+        }
+
+        if (archiveMode === 'year') {
+          await client.moveEmail(email.id, yearMailbox.id);
+          movedCount++;
+        } else {
+          // month mode
+          const yearId = yearMailbox.originalId || yearMailbox.id;
+          let monthMailbox = currentMailboxes.find(
+            m => m.name === month && m.parentId === yearId
+          );
+          if (!monthMailbox) {
+            monthMailbox = await client.createMailbox(month, yearId);
+            await fetchMailboxes(client);
+          }
+          await client.moveEmail(email.id, monthMailbox.id);
+          movedCount++;
+        }
+      }
+
+      setReorganizeResult(t('archive_mode.reorganize_success', { count: movedCount }));
+    } catch (error) {
+      console.error('Failed to reorganize archive:', error);
+      setReorganizeResult(t('archive_mode.reorganize_error'));
+    } finally {
+      setIsReorganizing(false);
+    }
+  };
+
   return (
     <SettingsSection title={t('title')} description={t('description')}>
       {/* Mark as Read */}
@@ -67,6 +137,40 @@ export function EmailSettings() {
         </div>
       </SettingItem>
 
+      {/* Archive Mode */}
+      <SettingItem label={t('archive_mode.label')} description={t('archive_mode.description')}>
+        <div className="flex flex-col gap-2">
+          <Select
+            value={archiveMode}
+            onChange={(value) => updateSetting('archiveMode', value as ArchiveMode)}
+            options={[
+              { value: 'single', label: t('archive_mode.single') },
+              { value: 'year', label: t('archive_mode.year') },
+              { value: 'month', label: t('archive_mode.month') },
+            ]}
+          />
+          {archiveMode !== 'single' && (
+            <div className="flex flex-col gap-2">
+              <button
+                onClick={handleReorganizeArchive}
+                disabled={isReorganizing}
+                className="flex items-center gap-2 px-3 py-1.5 bg-muted hover:bg-accent rounded-md transition-colors text-sm disabled:opacity-50"
+              >
+                {isReorganizing ? (
+                  <Loader2 className="w-4 h-4 animate-spin" />
+                ) : (
+                  <FolderSync className="w-4 h-4" />
+                )}
+                <span>{t('archive_mode.reorganize')}</span>
+              </button>
+              {reorganizeResult && (
+                <p className="text-xs text-muted-foreground">{reorganizeResult}</p>
+              )}
+            </div>
+          )}
+        </div>
+      </SettingItem>
+
       {/* Permanently Delete Junk */}
       <SettingItem label={t('permanently_delete_junk.label')} description={t('permanently_delete_junk.description')}>
         <ToggleSwitch
@@ -104,6 +208,14 @@ export function EmailSettings() {
         />
       </SettingItem>
 
+      {/* Always Light Mode for Emails */}
+      <SettingItem label={t('always_light_mode.label')} description={t('always_light_mode.description')}>
+        <ToggleSwitch
+          checked={emailAlwaysLightMode}
+          onChange={(checked) => updateSetting('emailAlwaysLightMode', checked)}
+        />
+      </SettingItem>
+
       {/* External Content */}
       <SettingItem label={t('external_content.label')} description={t('external_content.description')}>
         <Select

components/settings/folder-settings.tsx

@@ -490,21 +490,34 @@ export function FolderSettings() {
 
       {/* Standard Folder Roles — advanced section */}
       <SettingsSection title={t('standard_roles')} description={t('standard_roles_description')}>
-        {STANDARD_ROLES.map((role) => (
+        {STANDARD_ROLES.map((role) => {
-          <SettingItem key={role} label={t(`role_${role}`)}>
+          // Disambiguate duplicate folder names by appending parent path
-            <Select
+          const nameCounts = new Map<string, number>();
-              value={getRoleMailboxId(role)}
+          ownMailboxes.forEach(mb => nameCounts.set(mb.name, (nameCounts.get(mb.name) || 0) + 1));
-              onChange={(value) => handleRoleChange(role, value)}
+          const getParentPath = (mb: { parentId?: string; name: string }) => {
-              options={[
+            if (!mb.parentId) return '';
-                { value: '', label: t('role_none') },
+            const parent = ownMailboxes.find(p => p.id === mb.parentId);
-                ...ownMailboxes.map(mb => ({
+            return parent ? `${parent.name}/` : '';
-                  value: mb.id,
+          };
-                  label: mb.name,
+
-                })),
+          return (
-              ]}
+            <SettingItem key={role} label={t(`role_${role}`)}>
-            />
+              <Select
-          </SettingItem>
+                value={getRoleMailboxId(role)}
-        ))}
+                onChange={(value) => handleRoleChange(role, value)}
+                options={[
+                  { value: '', label: t('role_none') },
+                  ...ownMailboxes.map(mb => ({
+                    value: mb.id,
+                    label: (nameCounts.get(mb.name) || 0) > 1
+                      ? `${getParentPath(mb)}${mb.name} (${mb.id.slice(-6)})`
+                      : mb.name,
+                  })),
+                ]}
+              />
+            </SettingItem>
+          );
+        })}
       </SettingsSection>
     </div>
   );

components/settings/sidebar-apps-settings.tsx

@@ -0,0 +1,280 @@
+"use client";
+
+import { useState, useCallback } from "react";
+import { useTranslations } from "next-intl";
+import { Plus, Pencil, Trash2, ExternalLink, PanelRight, GripVertical } from "lucide-react";
+import { icons as lucideIcons, type LucideIcon } from "lucide-react";
+import { Button } from "@/components/ui/button";
+import { Input } from "@/components/ui/input";
+import { SettingsSection, SettingItem, ToggleSwitch } from "./settings-section";
+import { IconPicker } from "@/components/layout/icon-picker";
+import { useSettingsStore, type SidebarApp } from "@/stores/settings-store";
+import { useConfirmDialog } from "@/hooks/use-confirm-dialog";
+import { ConfirmDialog } from "@/components/ui/confirm-dialog";
+import { cn } from "@/lib/utils";
+
+interface SidebarAppFormData {
+  name: string;
+  url: string;
+  icon: string;
+  openMode: "tab" | "inline";
+}
+
+function AppForm({
+  app,
+  onSave,
+  onCancel,
+}: {
+  app?: SidebarApp;
+  onSave: (data: SidebarAppFormData) => void;
+  onCancel: () => void;
+}) {
+  const t = useTranslations("sidebar_apps");
+  const isEditing = !!app;
+
+  const [formData, setFormData] = useState<SidebarAppFormData>({
+    name: app?.name || "",
+    url: app?.url || "",
+    icon: app?.icon || "Globe",
+    openMode: app?.openMode || "tab",
+  });
+  const [errors, setErrors] = useState<Record<string, string>>({});
+
+  const validate = (): boolean => {
+    const newErrors: Record<string, string> = {};
+    if (!formData.name.trim()) {
+      newErrors.name = t("name_required");
+    }
+    if (!formData.url.trim()) {
+      newErrors.url = t("url_required");
+    } else {
+      try {
+        const parsed = new URL(formData.url);
+        if (!["http:", "https:"].includes(parsed.protocol)) {
+          newErrors.url = t("url_invalid");
+        }
+      } catch {
+        newErrors.url = t("url_invalid");
+      }
+    }
+    if (!formData.icon) {
+      newErrors.icon = t("icon_required");
+    }
+    setErrors(newErrors);
+    return Object.keys(newErrors).length === 0;
+  };
+
+  const handleSubmit = (e: React.FormEvent) => {
+    e.preventDefault();
+    if (!validate()) return;
+    onSave(formData);
+  };
+
+  const SelectedIcon = formData.icon
+    ? (lucideIcons[formData.icon as keyof typeof lucideIcons] as LucideIcon | undefined)
+    : null;
+
+  return (
+    <form onSubmit={handleSubmit} className="space-y-4 p-4 border border-border rounded-lg bg-secondary/30">
+      <div>
+        <label className="text-sm font-medium">{t("name_label")}</label>
+        <Input
+          value={formData.name}
+          onChange={(e) => setFormData({ ...formData, name: e.target.value })}
+          placeholder={t("name_placeholder")}
+          className="mt-1"
+        />
+        {errors.name && <p className="text-xs text-destructive mt-1">{errors.name}</p>}
+      </div>
+
+      <div>
+        <label className="text-sm font-medium">{t("url_label")}</label>
+        <Input
+          value={formData.url}
+          onChange={(e) => setFormData({ ...formData, url: e.target.value })}
+          placeholder="https://example.com"
+          className="mt-1"
+        />
+        {errors.url && <p className="text-xs text-destructive mt-1">{errors.url}</p>}
+      </div>
+
+      <div>
+        <label className="text-sm font-medium block mb-1">{t("icon_label")}</label>
+        <div className="flex items-center gap-2 mb-2">
+          {SelectedIcon && (
+            <div className="w-8 h-8 rounded-md bg-muted flex items-center justify-center">
+              <SelectedIcon className="w-4 h-4" />
+            </div>
+          )}
+          <span className="text-sm text-muted-foreground">{formData.icon}</span>
+        </div>
+        <IconPicker value={formData.icon} onChange={(icon) => setFormData({ ...formData, icon })} />
+        {errors.icon && <p className="text-xs text-destructive mt-1">{errors.icon}</p>}
+      </div>
+
+      <div>
+        <label className="text-sm font-medium block mb-2">{t("open_mode_label")}</label>
+        <div className="flex gap-2">
+          <button
+            type="button"
+            onClick={() => setFormData({ ...formData, openMode: "tab" })}
+            className={cn(
+              "flex items-center gap-2 px-3 py-2 rounded-md text-sm border transition-colors",
+              formData.openMode === "tab"
+                ? "border-primary bg-primary/10 text-primary"
+                : "border-border hover:bg-muted"
+            )}
+          >
+            <ExternalLink className="w-4 h-4" />
+            {t("open_new_tab")}
+          </button>
+          <button
+            type="button"
+            onClick={() => setFormData({ ...formData, openMode: "inline" })}
+            className={cn(
+              "flex items-center gap-2 px-3 py-2 rounded-md text-sm border transition-colors",
+              formData.openMode === "inline"
+                ? "border-primary bg-primary/10 text-primary"
+                : "border-border hover:bg-muted"
+            )}
+          >
+            <PanelRight className="w-4 h-4" />
+            {t("open_inline")}
+          </button>
+        </div>
+      </div>
+
+      <div className="flex gap-2 justify-end">
+        <Button type="button" variant="ghost" size="sm" onClick={onCancel}>
+          {t("cancel")}
+        </Button>
+        <Button type="submit" size="sm">
+          {isEditing ? t("update") : t("add")}
+        </Button>
+      </div>
+    </form>
+  );
+}
+
+export function SidebarAppsSettings() {
+  const t = useTranslations("settings.sidebar_apps");
+  const tApps = useTranslations("sidebar_apps");
+  const { sidebarApps, keepAppsLoaded, addSidebarApp, updateSidebarApp, removeSidebarApp, updateSetting } = useSettingsStore();
+  const [editingApp, setEditingApp] = useState<string | null>(null);
+  const [showAddForm, setShowAddForm] = useState(false);
+  const { dialogProps: confirmDialogProps, confirm: confirmDialog } = useConfirmDialog();
+
+  const handleAdd = useCallback((data: SidebarAppFormData) => {
+    const id = `app-${Date.now()}-${Math.random().toString(36).slice(2, 7)}`;
+    addSidebarApp({ id, ...data });
+    setShowAddForm(false);
+  }, [addSidebarApp]);
+
+  const handleUpdate = useCallback((id: string, data: SidebarAppFormData) => {
+    updateSidebarApp(id, data);
+    setEditingApp(null);
+  }, [updateSidebarApp]);
+
+  const handleDelete = useCallback(async (app: SidebarApp) => {
+    const confirmed = await confirmDialog({
+      title: tApps("delete_confirm_title"),
+      message: tApps("delete_confirm", { name: app.name }),
+      confirmText: tApps("delete"),
+      variant: 'destructive',
+    });
+    if (!confirmed) return;
+    removeSidebarApp(app.id);
+  }, [confirmDialog, tApps, removeSidebarApp]);
+
+  return (
+    <>
+      <SettingsSection title={t("title")} description={t("description")}>
+        <SettingItem label={t("keep_loaded")} description={t("keep_loaded_description")}>
+          <ToggleSwitch
+            checked={keepAppsLoaded}
+            onChange={(v) => updateSetting("keepAppsLoaded", v)}
+          />
+        </SettingItem>
+      </SettingsSection>
+
+      <SettingsSection title={t("manage_title")} description={t("manage_description")}>
+        <div className="space-y-3">
+          {sidebarApps.length === 0 && !showAddForm && (
+            <p className="text-sm text-muted-foreground py-4 text-center">{tApps("no_apps_hint")}</p>
+          )}
+
+          {sidebarApps.map((app) => {
+            if (editingApp === app.id) {
+              return (
+                <AppForm
+                  key={app.id}
+                  app={app}
+                  onSave={(data) => handleUpdate(app.id, data)}
+                  onCancel={() => setEditingApp(null)}
+                />
+              );
+            }
+
+            const AppIcon = lucideIcons[app.icon as keyof typeof lucideIcons] as LucideIcon | undefined;
+            return (
+              <div
+                key={app.id}
+                className="flex items-center gap-3 p-3 border border-border rounded-lg hover:bg-muted/50 transition-colors"
+              >
+                <GripVertical className="w-4 h-4 text-muted-foreground/50 flex-shrink-0" />
+                <div className="w-8 h-8 rounded-md bg-muted flex items-center justify-center flex-shrink-0">
+                  {AppIcon ? <AppIcon className="w-4 h-4" /> : null}
+                </div>
+                <div className="flex-1 min-w-0">
+                  <div className="text-sm font-medium truncate">{app.name}</div>
+                  <div className="text-xs text-muted-foreground truncate">{app.url}</div>
+                </div>
+                <span className={cn(
+                  "text-[10px] px-1.5 py-0.5 rounded-full flex-shrink-0",
+                  app.openMode === "inline"
+                    ? "bg-blue-500/10 text-blue-600 dark:text-blue-400"
+                    : "bg-muted text-muted-foreground"
+                )}>
+                  {app.openMode === "inline" ? tApps("inline_badge") : tApps("tab_badge")}
+                </span>
+                <button
+                  onClick={() => setEditingApp(app.id)}
+                  className="p-1.5 rounded-md hover:bg-muted text-muted-foreground hover:text-foreground transition-colors"
+                >
+                  <Pencil className="w-3.5 h-3.5" />
+                </button>
+                <button
+                  onClick={() => handleDelete(app)}
+                  className="p-1.5 rounded-md hover:bg-destructive/10 text-muted-foreground hover:text-destructive transition-colors"
+                >
+                  <Trash2 className="w-3.5 h-3.5" />
+                </button>
+              </div>
+            );
+          })}
+
+          {showAddForm && (
+            <AppForm
+              onSave={handleAdd}
+              onCancel={() => setShowAddForm(false)}
+            />
+          )}
+
+          {!showAddForm && !editingApp && (
+            <Button
+              variant="outline"
+              size="sm"
+              onClick={() => setShowAddForm(true)}
+              className="w-full"
+            >
+              <Plus className="w-4 h-4 mr-2" />
+              {tApps("add_new")}
+            </Button>
+          )}
+        </div>
+      </SettingsSection>
+
+      <ConfirmDialog {...confirmDialogProps} />
+    </>
+  );
+}

components/settings/smime-certificate-modal.tsx

@@ -0,0 +1,117 @@
+"use client";
+
+import { useId } from "react";
+import { useFocusTrap } from "@/hooks/use-focus-trap";
+import { useTranslations } from "next-intl";
+import { Button } from "@/components/ui/button";
+import { ShieldCheck, X } from "lucide-react";
+import type { SmimeKeyRecord, SmimePublicCert } from "@/lib/smime/types";
+
+interface SmimeCertificateModalProps {
+  isOpen: boolean;
+  onClose: () => void;
+  record: SmimeKeyRecord | SmimePublicCert | null;
+  type: "private" | "public";
+}
+
+export function SmimeCertificateModal({
+  isOpen,
+  onClose,
+  record,
+  type,
+}: SmimeCertificateModalProps) {
+  const t = useTranslations("smime");
+  const id = useId();
+
+  const dialogRef = useFocusTrap({
+    isActive: isOpen,
+    onEscape: onClose,
+    restoreFocus: true,
+  });
+
+  if (!isOpen || !record) return null;
+
+  const isExpired = new Date(record.notAfter) < new Date();
+  const isNotYetValid = new Date(record.notBefore) > new Date();
+
+  const rows: { label: string; value: string }[] = [
+    { label: t("cert_subject"), value: record.subject ?? "" },
+    { label: t("cert_issuer"), value: record.issuer ?? "" },
+    { label: t("cert_email"), value: record.email },
+    {
+      label: t("cert_validity"),
+      value: `${new Date(record.notBefore).toLocaleDateString()} — ${new Date(record.notAfter).toLocaleDateString()}`,
+    },
+    { label: t("cert_fingerprint"), value: record.fingerprint },
+  ];
+
+  if ("serialNumber" in record) {
+    rows.splice(2, 0, { label: t("cert_serial"), value: record.serialNumber });
+  }
+
+  if ("algorithm" in record) {
+    rows.push({ label: t("cert_algorithm"), value: record.algorithm });
+  }
+
+  if ("capabilities" in record) {
+    const caps: string[] = [];
+    if (record.capabilities.canSign) caps.push(t("cap_sign"));
+    if (record.capabilities.canEncrypt) caps.push(t("cap_encrypt"));
+    rows.push({ label: t("cert_capabilities"), value: caps.join(", ") || t("cap_none") });
+  }
+
+  if ("source" in record) {
+    rows.push({ label: t("cert_source"), value: record.source });
+  }
+
+  return (
+    <div className="fixed inset-0 bg-black/50 backdrop-blur-[1px] flex items-center justify-center z-[60] p-4 animate-in fade-in duration-150">
+      <div
+        ref={dialogRef}
+        role="dialog"
+        aria-modal="true"
+        aria-labelledby={`${id}-title`}
+        className="bg-background border border-border rounded-lg shadow-xl w-full max-w-lg animate-in zoom-in-95 duration-200"
+      >
+        <div className="flex items-center justify-between p-6 pb-4 border-b border-border">
+          <div className="flex items-center gap-3">
+            <div className="w-9 h-9 rounded-full bg-primary/10 flex items-center justify-center">
+              <ShieldCheck className="w-5 h-5 text-primary" />
+            </div>
+            <h2 id={`${id}-title`} className="text-lg font-semibold text-foreground">
+              {t("certificate_details")}
+            </h2>
+          </div>
+          <Button variant="ghost" size="icon" onClick={onClose}>
+            <X className="w-4 h-4" />
+          </Button>
+        </div>
+
+        <div className="p-6 space-y-3 max-h-[60vh] overflow-y-auto">
+          {(isExpired || isNotYetValid) && (
+            <div className="px-3 py-2 rounded-md bg-destructive/10 text-destructive text-sm">
+              {isExpired ? t("cert_expired") : t("cert_not_yet_valid")}
+            </div>
+          )}
+
+          {rows.map(({ label, value }) => (
+            <div key={label}>
+              <dt className="text-xs font-medium text-muted-foreground uppercase tracking-wide">
+                {label}
+              </dt>
+              <dd className="text-sm text-foreground mt-0.5 break-all font-mono">
+                {value}
+              </dd>
+            </div>
+          ))}
+        </div>
+
+        <div className="flex justify-end px-6 pb-6">
+          <Button variant="ghost" onClick={onClose}>
+            {t("close")}
+          </Button>
+        </div>
+      </div>
+    </div>
+  );
+}

components/settings/smime-passphrase-dialog.tsx

@@ -0,0 +1,169 @@
+"use client";
+
+import { useState, useId } from "react";
+import { useFocusTrap } from "@/hooks/use-focus-trap";
+import { useTranslations } from "next-intl";
+import { Button } from "@/components/ui/button";
+import { Input } from "@/components/ui/input";
+import { KeyRound, Eye, EyeOff } from "lucide-react";
+
+interface SmimePassphraseDialogProps {
+  isOpen: boolean;
+  onClose: () => void;
+  onSubmit: (passphrase: string) => void | Promise<void>;
+  title: string;
+  description?: string;
+  submitText?: string;
+  error?: string | null;
+  /** Show a second passphrase field for import/export confirmation. */
+  showConfirm?: boolean;
+}
+
+export function SmimePassphraseDialog({
+  isOpen,
+  onClose,
+  onSubmit,
+  title,
+  description,
+  submitText,
+  error,
+  showConfirm = false,
+}: SmimePassphraseDialogProps) {
+  const t = useTranslations("smime");
+  const id = useId();
+  const [passphrase, setPassphrase] = useState("");
+  const [confirm, setConfirm] = useState("");
+  const [showPassword, setShowPassword] = useState(false);
+  const [isSubmitting, setIsSubmitting] = useState(false);
+
+  const dialogRef = useFocusTrap({
+    isActive: isOpen,
+    onEscape: onClose,
+    restoreFocus: true,
+  });
+
+  if (!isOpen) return null;
+
+  const mismatch = showConfirm && passphrase !== confirm && confirm.length > 0;
+
+  const handleSubmit = async (e: React.FormEvent) => {
+    e.preventDefault();
+    if (!passphrase || (showConfirm && passphrase !== confirm)) return;
+    setIsSubmitting(true);
+    try {
+      await onSubmit(passphrase);
+    } finally {
+      setIsSubmitting(false);
+    }
+  };
+
+  const handleClose = () => {
+    setPassphrase("");
+    setConfirm("");
+    setShowPassword(false);
+    onClose();
+  };
+
+  return (
+    <div className="fixed inset-0 bg-black/50 backdrop-blur-[1px] flex items-center justify-center z-[60] p-4 animate-in fade-in duration-150">
+      <div
+        ref={dialogRef}
+        role="dialog"
+        aria-modal="true"
+        aria-labelledby={`${id}-title`}
+        aria-describedby={description ? `${id}-desc` : undefined}
+        className="bg-background border border-border rounded-lg shadow-xl w-full max-w-md animate-in zoom-in-95 duration-200"
+      >
+        <form onSubmit={handleSubmit}>
+          <div className="p-6">
+            <div className="flex items-start gap-4">
+              <div className="flex-shrink-0 w-10 h-10 rounded-full bg-primary/10 flex items-center justify-center">
+                <KeyRound className="w-5 h-5 text-primary" />
+              </div>
+              <div className="flex-1 min-w-0">
+                <h2
+                  id={`${id}-title`}
+                  className="text-lg font-semibold text-foreground"
+                >
+                  {title}
+                </h2>
+                {description && (
+                  <p
+                    id={`${id}-desc`}
+                    className="text-sm text-muted-foreground mt-1"
+                  >
+                    {description}
+                  </p>
+                )}
+              </div>
+            </div>
+
+            <div className="mt-4 space-y-3">
+              <div className="relative">
+                <Input
+                  type={showPassword ? "text" : "password"}
+                  value={passphrase}
+                  onChange={(e) => setPassphrase(e.target.value)}
+                  placeholder={t("passphrase_placeholder")}
+                  autoFocus
+                  className="pr-10"
+                  autoComplete="off"
+                />
+                <button
+                  type="button"
+                  onClick={() => setShowPassword(!showPassword)}
+                  className="absolute right-2 top-1/2 -translate-y-1/2 p-1 text-muted-foreground hover:text-foreground"
+                  aria-label={showPassword ? t("hide_passphrase") : t("show_passphrase")}
+                >
+                  {showPassword ? (
+                    <EyeOff className="w-4 h-4" />
+                  ) : (
+                    <Eye className="w-4 h-4" />
+                  )}
+                </button>
+              </div>
+
+              {showConfirm && (
+                <div>
+                  <Input
+                    type={showPassword ? "text" : "password"}
+                    value={confirm}
+                    onChange={(e) => setConfirm(e.target.value)}
+                    placeholder={t("confirm_passphrase_placeholder")}
+                    autoComplete="off"
+                  />
+                  {mismatch && (
+                    <p className="text-xs text-destructive mt-1">
+                      {t("passphrase_mismatch")}
+                    </p>
+                  )}
+                </div>
+              )}
+
+              {error && (
+                <p className="text-sm text-destructive">{error}</p>
+              )}
+            </div>
+          </div>
+
+          <div className="flex justify-end gap-2 px-6 pb-6">
+            <Button
+              type="button"
+              variant="ghost"
+              onClick={handleClose}
+              disabled={isSubmitting}
+            >
+              {t("cancel")}
+            </Button>
+            <Button
+              type="submit"
+              disabled={!passphrase || isSubmitting || (showConfirm && passphrase !== confirm)}
+            >
+              {isSubmitting ? t("processing") : (submitText ?? t("unlock"))}
+            </Button>
+          </div>
+        </form>
+      </div>
+    </div>
+  );
+}

components/settings/smime-settings.tsx

@@ -0,0 +1,559 @@
+"use client";
+
+import { useState, useEffect, useRef } from "react";
+import { useTranslations } from "next-intl";
+import {
+  Upload,
+  Trash2,
+  Eye,
+  Lock,
+  Unlock,
+  Download,
+  ShieldCheck,
+  ShieldAlert,
+  Users,
+} from "lucide-react";
+import { Button } from "@/components/ui/button";
+import { SettingsSection, SettingItem, ToggleSwitch } from "@/components/settings/settings-section";
+import { SmimePassphraseDialog } from "@/components/settings/smime-passphrase-dialog";
+import { SmimeCertificateModal } from "@/components/settings/smime-certificate-modal";
+import { useSmimeStore } from "@/stores/smime-store";
+import { useIdentityStore } from "@/stores/identity-store";
+import { exportPkcs12, downloadPkcs12 } from "@/lib/smime/pkcs12-export";
+import type { SmimeKeyRecord, SmimePublicCert } from "@/lib/smime/types";
+
+export function SmimeSettings() {
+  const t = useTranslations("smime");
+  const {
+    keyRecords,
+    publicCerts,
+    identityKeyBindings,
+    defaultSignIdentity,
+    defaultEncrypt,
+    rememberUnlockedKeys,
+    autoImportSignerCerts,
+    isLoading,
+    error,
+    load,
+    importPKCS12,
+    removeKeyRecord,
+    removePublicCert,
+    bindIdentityToKey,
+    unlockKey,
+    lockKey,
+    setSignDefault,
+    setEncryptDefault,
+    setRememberUnlockedKeys,
+    setAutoImportSignerCerts,
+    isKeyUnlocked,
+    setError,
+  } = useSmimeStore();
+
+  const { identities } = useIdentityStore();
+
+  // Local UI state
+  const [importDialogOpen, setImportDialogOpen] = useState(false);
+  const [unlockDialogOpen, setUnlockDialogOpen] = useState(false);
+  const [unlockTargetId, setUnlockTargetId] = useState<string | null>(null);
+  const [certModalRecord, setCertModalRecord] = useState<SmimeKeyRecord | SmimePublicCert | null>(null);
+  const [certModalType, setCertModalType] = useState<"private" | "public">("private");
+  const [importError, setImportError] = useState<string | null>(null);
+  const [unlockError, setUnlockError] = useState<string | null>(null);
+  const [pendingFile, setPendingFile] = useState<ArrayBuffer | null>(null);
+  const [pendingP12Pass, setPendingP12Pass] = useState("");
+  const fileInputRef = useRef<HTMLInputElement>(null);
+  const pubCertInputRef = useRef<HTMLInputElement>(null);
+
+  // State for the two-step PKCS#12 flow
+  const [importStep, setImportStep] = useState<"p12" | "storage">("p12");
+
+  // Export flow state
+  const [exportDialogOpen, setExportDialogOpen] = useState(false);
+  const [exportTargetRecord, setExportTargetRecord] = useState<SmimeKeyRecord | null>(null);
+  const [exportStep, setExportStep] = useState<"storage" | "export">("storage");
+  const [exportStoragePass, setExportStoragePass] = useState("");
+  const [exportError, setExportError] = useState<string | null>(null);
+
+  useEffect(() => {
+    load();
+  }, [load]);
+
+  // ── PKCS#12 import flow ────────────────────────────────────────
+
+  const handleFileSelect = (e: React.ChangeEvent<HTMLInputElement>) => {
+    const file = e.target.files?.[0];
+    if (!file) return;
+    const reader = new FileReader();
+    reader.onload = () => {
+      setPendingFile(reader.result as ArrayBuffer);
+      setImportStep("p12");
+      setImportError(null);
+      setImportDialogOpen(true);
+    };
+    reader.readAsArrayBuffer(file);
+    // Reset so same file can be re-selected
+    e.target.value = "";
+  };
+
+  const handleImportSubmit = async (passphrase: string) => {
+    if (importStep === "p12") {
+      setPendingP12Pass(passphrase);
+      setImportStep("storage");
+      setImportError(null);
+      return;
+    }
+
+    // Storage passphrase step
+    if (!pendingFile) return;
+    try {
+      await importPKCS12(pendingFile, pendingP12Pass, passphrase);
+      setImportDialogOpen(false);
+      setPendingFile(null);
+      setPendingP12Pass("");
+      setImportError(null);
+    } catch (err) {
+      setImportError(err instanceof Error ? err.message : "Import failed");
+    }
+  };
+
+  // ── Public cert import ─────────────────────────────────────────
+
+  const handlePublicCertFile = (e: React.ChangeEvent<HTMLInputElement>) => {
+    const file = e.target.files?.[0];
+    if (!file) return;
+    const reader = new FileReader();
+    reader.onload = async () => {
+      try {
+        const store = useSmimeStore.getState();
+        await store.importPublicCert(reader.result as ArrayBuffer, "manual");
+      } catch (err) {
+        setError(err instanceof Error ? err.message : "Failed to import certificate");
+      }
+    };
+    reader.readAsArrayBuffer(file);
+    e.target.value = "";
+  };
+
+  // ── Unlock ─────────────────────────────────────────────────────
+
+  const handleUnlockRequest = (id: string) => {
+    setUnlockTargetId(id);
+    setUnlockError(null);
+    setUnlockDialogOpen(true);
+  };
+
+  const handleUnlockSubmit = async (passphrase: string) => {
+    if (!unlockTargetId) return;
+    try {
+      await unlockKey(unlockTargetId, passphrase);
+      setUnlockDialogOpen(false);
+      setUnlockTargetId(null);
+      setUnlockError(null);
+    } catch (err) {
+      setUnlockError(err instanceof Error ? err.message : "Unlock failed");
+    }
+  };
+
+  // ── Export flow ────────────────────────────────────────────────
+
+  const handleExportRequest = (record: SmimeKeyRecord) => {
+    setExportTargetRecord(record);
+    setExportStep("storage");
+    setExportStoragePass("");
+    setExportError(null);
+    setExportDialogOpen(true);
+  };
+
+  const handleExportSubmit = async (passphrase: string) => {
+    if (!exportTargetRecord) return;
+
+    if (exportStep === "storage") {
+      // Verify storage passphrase by attempting to decrypt
+      try {
+        const { decryptPrivateKeyBytes } = await import("@/lib/smime/pkcs12-import");
+        await decryptPrivateKeyBytes(exportTargetRecord, passphrase);
+        setExportStoragePass(passphrase);
+        setExportStep("export");
+        setExportError(null);
+      } catch {
+        setExportError(t("incorrect_passphrase"));
+      }
+      return;
+    }
+
+    // Export passphrase step
+    try {
+      const p12Bytes = await exportPkcs12(exportTargetRecord, exportStoragePass, passphrase);
+      const filename = `${exportTargetRecord.email.replace(/[^a-zA-Z0-9.-]/g, '_')}.p12`;
+      downloadPkcs12(p12Bytes, filename);
+      setExportDialogOpen(false);
+      setExportTargetRecord(null);
+      setExportStoragePass("");
+      setExportError(null);
+    } catch (err) {
+      setExportError(err instanceof Error ? err.message : "Export failed");
+    }
+  };
+
+  // ── Helpers ────────────────────────────────────────────────────
+
+  const isExpired = (dateStr: string) => new Date(dateStr) < new Date();
+
+  const formatDate = (dateStr: string) => {
+    try {
+      return new Date(dateStr).toLocaleDateString();
+    } catch {
+      return dateStr;
+    }
+  };
+
+  const getBoundIdentityNames = (keyId: string): string[] => {
+    return Object.entries(identityKeyBindings)
+      .filter(([, kId]) => kId === keyId)
+      .map(([identityId]) => {
+        const identity = identities.find((i) => i.id === identityId);
+        return identity?.email ?? identityId;
+      });
+  };
+
+  return (
+    <div className="space-y-8">
+      {error && (
+        <div className="px-4 py-3 rounded-md bg-destructive/10 text-destructive text-sm">
+          {error}
+        </div>
+      )}
+
+      {/* ── Your Certificates ──────────────────────────────────── */}
+      <SettingsSection
+        title={t("your_certificates")}
+        description={t("your_certificates_desc")}
+      >
+        <div className="space-y-2">
+          {keyRecords.map((record) => {
+            const expired = isExpired(record.notAfter);
+            const unlocked = isKeyUnlocked(record.id);
+            const boundIdentities = getBoundIdentityNames(record.id);
+
+            return (
+              <div
+                key={record.id}
+                className="flex items-center justify-between p-3 rounded-lg border border-border"
+              >
+                <div className="flex items-center gap-3 min-w-0 flex-1">
+                  <div className={`w-8 h-8 rounded-full flex items-center justify-center ${expired ? "bg-destructive/10" : "bg-primary/10"}`}>
+                    {expired ? (
+                      <ShieldAlert className="w-4 h-4 text-destructive" />
+                    ) : (
+                      <ShieldCheck className="w-4 h-4 text-primary" />
+                    )}
+                  </div>
+                  <div className="min-w-0">
+                    <p className="text-sm font-medium text-foreground truncate">
+                      {record.email || record.subject}
+                    </p>
+                    <p className="text-xs text-muted-foreground">
+                      {record.issuer} · {t("expires")} {formatDate(record.notAfter)}
+                      {expired && <span className="text-destructive ml-1">({t("expired")})</span>}
+                    </p>
+                    {boundIdentities.length > 0 && (
+                      <p className="text-xs text-muted-foreground">
+                        {t("bound_to")}: {boundIdentities.join(", ")}
+                      </p>
+                    )}
+                  </div>
+                </div>
+                <div className="flex items-center gap-1">
+                  {unlocked ? (
+                    <Button
+                      variant="ghost"
+                      size="icon"
+                      onClick={() => lockKey(record.id)}
+                      title={t("lock")}
+                    >
+                      <Unlock className="w-4 h-4 text-green-600" />
+                    </Button>
+                  ) : (
+                    <Button
+                      variant="ghost"
+                      size="icon"
+                      onClick={() => handleUnlockRequest(record.id)}
+                      title={t("unlock")}
+                    >
+                      <Lock className="w-4 h-4" />
+                    </Button>
+                  )}
+                  <Button
+                    variant="ghost"
+                    size="icon"
+                    onClick={() => {
+                      setCertModalRecord(record);
+                      setCertModalType("private");
+                    }}
+                    title={t("details")}
+                  >
+                    <Eye className="w-4 h-4" />
+                  </Button>
+                  <Button
+                    variant="ghost"
+                    size="icon"
+                    onClick={() => handleExportRequest(record)}
+                    title={t("export")}
+                  >
+                    <Download className="w-4 h-4" />
+                  </Button>
+                  <Button
+                    variant="ghost"
+                    size="icon"
+                    onClick={() => removeKeyRecord(record.id)}
+                    title={t("delete")}
+                  >
+                    <Trash2 className="w-4 h-4 text-destructive" />
+                  </Button>
+                </div>
+              </div>
+            );
+          })}
+
+          {keyRecords.length === 0 && !isLoading && (
+            <p className="text-sm text-muted-foreground py-4 text-center">
+              {t("no_certificates")}
+            </p>
+          )}
+        </div>
+
+        <input
+          ref={fileInputRef}
+          type="file"
+          accept=".p12,.pfx"
+          className="hidden"
+          onChange={handleFileSelect}
+        />
+        <Button
+          variant="outline"
+          onClick={() => fileInputRef.current?.click()}
+          disabled={isLoading}
+          className="mt-2"
+        >
+          <Upload className="w-4 h-4 mr-2" />
+          {t("import_pkcs12")}
+        </Button>
+      </SettingsSection>
+
+      {/* ── Recipient Certificates ─────────────────────────────── */}
+      <SettingsSection
+        title={t("recipient_certificates")}
+        description={t("recipient_certificates_desc")}
+      >
+        <div className="space-y-2">
+          {publicCerts.map((cert) => {
+            const expired = isExpired(cert.notAfter);
+
+            return (
+              <div
+                key={cert.id}
+                className="flex items-center justify-between p-3 rounded-lg border border-border"
+              >
+                <div className="flex items-center gap-3 min-w-0 flex-1">
+                  <div className="w-8 h-8 rounded-full bg-muted flex items-center justify-center">
+                    <Users className="w-4 h-4 text-muted-foreground" />
+                  </div>
+                  <div className="min-w-0">
+                    <p className="text-sm font-medium text-foreground truncate">
+                      {cert.email || cert.subject}
+                    </p>
+                    <p className="text-xs text-muted-foreground">
+                      {cert.issuer} · {cert.source}
+                      {expired && <span className="text-destructive ml-1">({t("expired")})</span>}
+                    </p>
+                  </div>
+                </div>
+                <div className="flex items-center gap-1">
+                  <Button
+                    variant="ghost"
+                    size="icon"
+                    onClick={() => {
+                      setCertModalRecord(cert);
+                      setCertModalType("public");
+                    }}
+                    title={t("details")}
+                  >
+                    <Eye className="w-4 h-4" />
+                  </Button>
+                  <Button
+                    variant="ghost"
+                    size="icon"
+                    onClick={() => removePublicCert(cert.id)}
+                    title={t("delete")}
+                  >
+                    <Trash2 className="w-4 h-4 text-destructive" />
+                  </Button>
+                </div>
+              </div>
+            );
+          })}
+
+          {publicCerts.length === 0 && !isLoading && (
+            <p className="text-sm text-muted-foreground py-4 text-center">
+              {t("no_recipient_certs")}
+            </p>
+          )}
+        </div>
+
+        <input
+          ref={pubCertInputRef}
+          type="file"
+          accept=".pem,.cer,.crt,.der"
+          className="hidden"
+          onChange={handlePublicCertFile}
+        />
+        <Button
+          variant="outline"
+          onClick={() => pubCertInputRef.current?.click()}
+          disabled={isLoading}
+          className="mt-2"
+        >
+          <Upload className="w-4 h-4 mr-2" />
+          {t("import_public_cert")}
+        </Button>
+      </SettingsSection>
+
+      {/* ── Identity Bindings ──────────────────────────────────── */}
+      {identities.length > 0 && keyRecords.length > 0 && (
+        <SettingsSection
+          title={t("identity_bindings")}
+          description={t("identity_bindings_desc")}
+        >
+          {identities.map((identity) => {
+            const boundKeyId = identityKeyBindings[identity.id];
+            return (
+              <SettingItem key={identity.id} label={identity.email}>
+                <select
+                  value={boundKeyId ?? ""}
+                  onChange={(e) =>
+                    bindIdentityToKey(identity.id, e.target.value || null)
+                  }
+                  className="text-sm bg-background border border-border rounded-md px-2 py-1"
+                >
+                  <option value="">{t("no_key_bound")}</option>
+                  {keyRecords.map((kr) => (
+                    <option key={kr.id} value={kr.id}>
+                      {kr.email} ({kr.algorithm})
+                    </option>
+                  ))}
+                </select>
+              </SettingItem>
+            );
+          })}
+        </SettingsSection>
+      )}
+
+      {/* ── Defaults ───────────────────────────────────────────── */}
+      <SettingsSection
+        title={t("defaults_title")}
+        description={t("defaults_desc")}
+      >
+        <SettingItem
+          label={t("encrypt_by_default")}
+          description={t("encrypt_by_default_desc")}
+        >
+          <ToggleSwitch
+            checked={defaultEncrypt}
+            onChange={setEncryptDefault}
+          />
+        </SettingItem>
+
+        <SettingItem
+          label={t("remember_unlocked")}
+          description={t("remember_unlocked_desc")}
+        >
+          <ToggleSwitch
+            checked={rememberUnlockedKeys}
+            onChange={setRememberUnlockedKeys}
+          />
+        </SettingItem>
+
+        <SettingItem
+          label={t("auto_import_signer_certs")}
+          description={t("auto_import_signer_certs_desc")}
+        >
+          <ToggleSwitch
+            checked={autoImportSignerCerts}
+            onChange={setAutoImportSignerCerts}
+          />
+        </SettingItem>
+
+        {identities.map((identity) => {
+          const bound = identityKeyBindings[identity.id];
+          if (!bound) return null;
+          return (
+            <SettingItem
+              key={identity.id}
+              label={`${t("sign_default_for")} ${identity.email}`}
+            >
+              <ToggleSwitch
+                checked={defaultSignIdentity[identity.id] ?? false}
+                onChange={(v) => setSignDefault(identity.id, v)}
+              />
+            </SettingItem>
+          );
+        })}
+      </SettingsSection>
+
+      {/* ── Dialogs ────────────────────────────────────────────── */}
+      <SmimePassphraseDialog
+        isOpen={importDialogOpen}
+        onClose={() => {
+          setImportDialogOpen(false);
+          setPendingFile(null);
+          setPendingP12Pass("");
+          setImportError(null);
+          setImportStep("p12");
+        }}
+        onSubmit={handleImportSubmit}
+        title={importStep === "p12" ? t("enter_p12_passphrase") : t("enter_storage_passphrase")}
+        description={importStep === "p12" ? t("p12_passphrase_desc") : t("storage_passphrase_desc")}
+        submitText={importStep === "p12" ? t("next") : t("import")}
+        error={importError}
+        showConfirm={importStep === "storage"}
+      />
+
+      <SmimePassphraseDialog
+        isOpen={unlockDialogOpen}
+        onClose={() => {
+          setUnlockDialogOpen(false);
+          setUnlockTargetId(null);
+          setUnlockError(null);
+        }}
+        onSubmit={handleUnlockSubmit}
+        title={t("unlock_key")}
+        description={t("unlock_key_desc")}
+        error={unlockError}
+      />
+
+      <SmimeCertificateModal
+        isOpen={!!certModalRecord}
+        onClose={() => setCertModalRecord(null)}
+        record={certModalRecord}
+        type={certModalType}
+      />
+
+      <SmimePassphraseDialog
+        isOpen={exportDialogOpen}
+        onClose={() => {
+          setExportDialogOpen(false);
+          setExportTargetRecord(null);
+          setExportStoragePass("");
+          setExportError(null);
+          setExportStep("storage");
+        }}
+        onSubmit={handleExportSubmit}
+        title={exportStep === "storage" ? t("enter_storage_passphrase") : t("enter_export_passphrase")}
+        description={exportStep === "storage" ? t("export_storage_desc") : t("export_passphrase_desc")}
+        submitText={exportStep === "storage" ? t("next") : t("export")}
+        error={exportError}
+        showConfirm={exportStep === "export"}
+      />
+    </div>
+  );
+}

docker-compose.yml

@@ -3,6 +3,9 @@ services:
     image: ghcr.io/bulwarkmail/webmail:latest
     ports:
       - "3000:3000"
+    environment:
+      - HOSTNAME=0.0.0.0 # Use "::" for IPv6
+      - PORT=3000
     env_file:
       - .env.local
     healthcheck:

eslint.config.mjs

@@ -70,6 +70,7 @@ export default [
       "*.config.js",
       "*.config.mjs",
       "e2e/**",
+      "local-data/**/*.mjs",
     ],
   },
 ];

hooks/use-config.ts

@@ -13,6 +13,9 @@ interface ConfigData {
   settingsSyncEnabled: boolean;
   stalwartFeaturesEnabled: boolean;
   devMode: boolean;
+  faviconUrl: string;
+  appLogoLightUrl: string;
+  appLogoDarkUrl: string;
   loginLogoLightUrl: string;
   loginLogoDarkUrl: string;
   loginCompanyName: string;
@@ -79,6 +82,9 @@ export function useConfig(): AppConfig {
     settingsSyncEnabled: configCache?.settingsSyncEnabled || false,
     stalwartFeaturesEnabled: configCache?.stalwartFeaturesEnabled ?? true,
     devMode: configCache?.devMode || false,
+    faviconUrl: configCache?.faviconUrl || '/branding/Bulwark_Favicon.svg',
+    appLogoLightUrl: configCache?.appLogoLightUrl || '',
+    appLogoDarkUrl: configCache?.appLogoDarkUrl || '',
     loginLogoLightUrl: configCache?.loginLogoLightUrl || '/branding/Bulwark_Logo_Color.svg',
     loginLogoDarkUrl: configCache?.loginLogoDarkUrl || '/branding/Bulwark_Logo_White.svg',
     loginCompanyName: configCache?.loginCompanyName || '',
@@ -103,6 +109,9 @@ export function useConfig(): AppConfig {
         settingsSyncEnabled: configCache.settingsSyncEnabled,
         stalwartFeaturesEnabled: configCache.stalwartFeaturesEnabled,
         devMode: configCache.devMode,
+        faviconUrl: configCache.faviconUrl,
+        appLogoLightUrl: configCache.appLogoLightUrl,
+        appLogoDarkUrl: configCache.appLogoDarkUrl,
         loginLogoLightUrl: configCache.loginLogoLightUrl,
         loginLogoDarkUrl: configCache.loginLogoDarkUrl,
         loginCompanyName: configCache.loginCompanyName,
@@ -128,6 +137,9 @@ export function useConfig(): AppConfig {
           settingsSyncEnabled: data.settingsSyncEnabled,
           stalwartFeaturesEnabled: data.stalwartFeaturesEnabled,
           devMode: data.devMode,
+          faviconUrl: data.faviconUrl,
+          appLogoLightUrl: data.appLogoLightUrl,
+          appLogoDarkUrl: data.appLogoDarkUrl,
           loginLogoLightUrl: data.loginLogoLightUrl,
           loginLogoDarkUrl: data.loginLogoDarkUrl,
           loginCompanyName: data.loginCompanyName,

hooks/use-sidebar-apps.ts

@@ -0,0 +1,49 @@
+import { useState, useCallback } from 'react';
+import { useSettingsStore } from '@/stores/settings-store';
+
+export interface InlineAppState {
+  id: string;
+  url: string;
+  name: string;
+}
+
+export function useSidebarApps() {
+  const [showAppsModal, setShowAppsModal] = useState(false);
+  const [inlineApp, setInlineApp] = useState<InlineAppState | null>(null);
+  const [loadedApps, setLoadedApps] = useState<InlineAppState[]>([]);
+  const keepAppsLoaded = useSettingsStore((s) => s.keepAppsLoaded);
+
+  const handleManageApps = useCallback(() => {
+    setShowAppsModal(true);
+  }, []);
+
+  const handleInlineApp = useCallback((appId: string, url: string, name: string) => {
+    const app = { id: appId, url, name };
+    setInlineApp(app);
+    setLoadedApps((prev) => {
+      if (prev.some((a) => a.id === appId)) return prev;
+      return [...prev, app];
+    });
+  }, []);
+
+  const closeInlineApp = useCallback(() => {
+    if (!keepAppsLoaded) {
+      setLoadedApps((prev) => prev.filter((a) => a.id !== inlineApp?.id));
+    }
+    setInlineApp(null);
+  }, [keepAppsLoaded, inlineApp]);
+
+  const closeAppsModal = useCallback(() => {
+    setShowAppsModal(false);
+  }, []);
+
+  return {
+    showAppsModal,
+    inlineApp,
+    loadedApps: keepAppsLoaded ? loadedApps : (inlineApp ? [inlineApp] : []),
+    handleManageApps,
+    handleInlineApp,
+    closeInlineApp,
+    closeAppsModal,
+  };
+}

hooks/use-time-grid-interactions.ts

@@ -239,9 +239,10 @@ export function useTimeGridInteractions({
       clearTimeout(clickTimerRef.current);
       clickTimerRef.current = null;
     }
-    const key = format(day, "yyyy-MM-dd");
+    const d = new Date(day);
-    setQuickCreate({ dayKey: key, day, hour, top: hour * hourHeight });
+    d.setHours(hour, 0, 0, 0);
-  }, [hourHeight]);
+    onCreateRange(d);
+  }, [onCreateRange]);
 
   const handleQuickCreateSubmit = useCallback(async (title: string) => {
     if (!quickCreate) return;

lib/__tests__/calendar-invitation.test.ts

@@ -335,10 +335,7 @@ describe('formatEventSummary', () => {
       duration: 'PT1H30M',
     });
     expect(summary.start).toBe('2026-02-17T10:00:00');
-    expect(summary.end).toBeTruthy();
+    expect(summary.end).toBe('2026-02-17T11:30:00');
-    const endDate = new Date(summary.end!);
-    expect(endDate.getHours()).toBe(new Date('2026-02-17T10:00:00').getHours() + 1);
-    expect(endDate.getMinutes()).toBe(new Date('2026-02-17T10:00:00').getMinutes() + 30);
   });
 
   it('uses utcStart and utcEnd when available', () => {
@@ -349,6 +346,38 @@ describe('formatEventSummary', () => {
     });
     expect(summary.start).toBe('2026-02-17T15:00:00Z');
     expect(summary.end).toBe('2026-02-17T16:00:00Z');
+    expect(summary.isAllDay).toBe(false);
+  });
+
+  it('prefers local start over utcStart for all-day events', () => {
+    const summary = formatEventSummary({
+      utcStart: '2026-03-16T00:00:00Z',
+      utcEnd: '2026-03-17T00:00:00Z',
+      start: '2026-03-16T00:00:00',
+      showWithoutTime: true,
+    });
+    expect(summary.start).toBe('2026-03-16T00:00:00');
+    expect(summary.end).toBe('2026-03-17T00:00:00Z');
+    expect(summary.isAllDay).toBe(true);
+  });
+
+  it('computes all-day end in local format when utcEnd is missing', () => {
+    const summary = formatEventSummary({
+      start: '2026-03-16T00:00:00',
+      duration: 'P1D',
+      showWithoutTime: true,
+    });
+    expect(summary.start).toBe('2026-03-16T00:00:00');
+    expect(summary.end).toBe('2026-03-17T00:00:00');
+    expect(summary.isAllDay).toBe(true);
+  });
+
+  it('returns local format end for timed events with local start', () => {
+    const summary = formatEventSummary({
+      start: '2026-02-17T10:00:00',
+      duration: 'PT1H30M',
+    });
+    expect(summary.end).toBe('2026-02-17T11:30:00');
   });
 });
 

lib/__tests__/config-route.test.ts

@@ -27,6 +27,9 @@ describe('config API route', () => {
     delete process.env.SETTINGS_SYNC_ENABLED;
     delete process.env.STALWART_FEATURES;
     delete process.env.DEV_MOCK_JMAP;
+    delete process.env.FAVICON_URL;
+    delete process.env.APP_LOGO_LIGHT_URL;
+    delete process.env.APP_LOGO_DARK_URL;
     delete process.env.LOGIN_COMPANY_NAME;
     delete process.env.LOGIN_IMPRINT_URL;
     delete process.env.LOGIN_PRIVACY_POLICY_URL;
@@ -60,6 +63,9 @@ describe('config API route', () => {
     expect(config.loginImprintUrl).toBe('');
     expect(config.loginPrivacyPolicyUrl).toBe('');
     expect(config.loginWebsiteUrl).toBe('');
+    expect(config.faviconUrl).toBe('/branding/Bulwark_Favicon.svg');
+    expect(config.appLogoLightUrl).toBe('');
+    expect(config.appLogoDarkUrl).toBe('');
   });
 
   it('should use runtime env vars over defaults', async () => {
@@ -142,4 +148,16 @@ describe('config API route', () => {
 
     expect(config.stalwartFeaturesEnabled).toBe(false);
   });
+
+  it('should return custom favicon and app logo URLs', async () => {
+    process.env.FAVICON_URL = '/branding/custom-favicon.svg';
+    process.env.APP_LOGO_LIGHT_URL = '/branding/my-logo.svg';
+    process.env.APP_LOGO_DARK_URL = '/branding/my-logo-white.svg';
+
+    const config = await getConfig();
+
+    expect(config.faviconUrl).toBe('/branding/custom-favicon.svg');
+    expect(config.appLogoLightUrl).toBe('/branding/my-logo.svg');
+    expect(config.appLogoDarkUrl).toBe('/branding/my-logo-white.svg');
+  });
 });

lib/__tests__/signature-utils.test.ts

@@ -0,0 +1,39 @@
+import { describe, expect, it } from 'vitest';
+
+import {
+  appendPlainTextSignature,
+  getPlainTextSignature,
+  hasMeaningfulHtmlBody,
+} from '../signature-utils';
+
+describe('signature-utils', () => {
+  describe('getPlainTextSignature', () => {
+    it('prefers text signatures when present', () => {
+      expect(getPlainTextSignature({ textSignature: 'Regards,\nAlice', htmlSignature: '<p>Ignored</p>' })).toBe('Regards,\nAlice');
+    });
+
+    it('converts html-only signatures into plain text', () => {
+      expect(getPlainTextSignature({ htmlSignature: '<p>Alice Example<br><a href="mailto:alice@example.com">alice@example.com</a></p>' })).toBe('Alice Example\nalice@example.com');
+    });
+  });
+
+  describe('appendPlainTextSignature', () => {
+    it('appends a converted html signature to the text body', () => {
+      expect(appendPlainTextSignature('Hello there', { htmlSignature: '<p>Alice<br>Engineering</p>' })).toBe('Hello there\n\n-- \nAlice\nEngineering');
+    });
+
+    it('leaves the body untouched when no signature exists', () => {
+      expect(appendPlainTextSignature('Hello there', {})).toBe('Hello there');
+    });
+  });
+
+  describe('hasMeaningfulHtmlBody', () => {
+    it('prefers html bodies that preserve signature formatting', () => {
+      expect(hasMeaningfulHtmlBody('<div>Hello</div><br><p>Alice</p>')).toBe(true);
+    });
+
+    it('ignores minimal wrapper html with a single block', () => {
+      expect(hasMeaningfulHtmlBody('<div>Hello world</div>')).toBe(false);
+    });
+  });
+});

lib/__tests__/translations.test.ts

@@ -1,3 +1,4 @@
+// @vitest-environment node
 import fs from 'fs';
 import path from 'path';
 import { describe, expect, it } from 'vitest';
@@ -87,6 +88,22 @@ function extractUsedKeys(filePath: string): string[] {
   return [...new Set(keys)];
 }
 
+function collectUsedKeysByFile(files: string[]): Map<string, string[]> {
+  const keyToFiles = new Map<string, string[]>();
+
+  for (const filePath of files) {
+    for (const key of extractUsedKeys(filePath)) {
+      const existing = keyToFiles.get(key) ?? [];
+      if (!existing.includes(filePath)) {
+        existing.push(filePath);
+        keyToFiles.set(key, existing);
+      }
+    }
+  }
+
+  return keyToFiles;
+}
+
 const locales = fs
   .readdirSync(localesDir)
   .filter((entry) => fs.statSync(path.join(localesDir, entry)).isDirectory());
@@ -120,19 +137,22 @@ describe('translations completeness', () => {
 describe('translations used in source code exist in en locale', () => {
   const srcDirs = ['components', 'app', 'hooks', 'lib', 'stores', 'contexts'].map((d) => path.join(rootDir, d));
   const allFiles = srcDirs.flatMap((d) => getSourceFiles(d));
-  const usedKeys = new Set<string>();
+  const usedKeysByFile = collectUsedKeysByFile(allFiles);
-  for (const f of allFiles) {
+  const usedKeys = [...usedKeysByFile.keys()].sort();
-    for (const k of extractUsedKeys(f)) {
-      usedKeys.add(k);
-    }
-  }
 
   it('all translation keys referenced in source should exist in en locale', () => {
-    const missing = [...usedKeys].sort().filter((key) => resolveKey(referenceData, key) === undefined);
+    const missing = usedKeys.filter((key) => resolveKey(referenceData, key) === undefined);
+    const details = missing.map((key) => {
+      const relativeFiles = (usedKeysByFile.get(key) ?? [])
+        .map((filePath) => path.relative(rootDir, filePath))
+        .sort();
+
+      return `${key}\n  used in:\n  - ${relativeFiles.join('\n  - ')}`;
+    });
 
     expect(
       missing,
-      `${missing.length} translation key(s) used in source code but missing from en locale:\n${missing.join('\n')}`,
+      `${missing.length} translation key(s) used in source code but missing from en locale:\n${details.join('\n')}`,
     ).toEqual([]);
   });
 });

lib/__tests__/vcard.test.ts

@@ -226,7 +226,7 @@ describe("parseVCard", () => {
     expect(result).toHaveLength(1);
     const card = result[0];
 
-    expect(card.gender).toEqual({ sex: "F", identity: "Female" });
+    expect(card.speakToAs).toEqual({ grammaticalGender: "feminine", pronouns: { p0: { pronouns: "Female" } } });
     expect(card.media?.m0).toEqual({
       kind: "logo",
       uri: "https://example.com/logo.png",
@@ -331,7 +331,7 @@ describe("generateVCard", () => {
         components: [{ kind: "given", value: "Jane" }],
         isOrdered: true,
       },
-      gender: { sex: "F", identity: "Female" },
+      speakToAs: { grammaticalGender: "feminine", pronouns: { p0: { pronouns: "Female" } } },
       media: {
         m0: { kind: "logo", uri: "https://example.com/logo.png", mediaType: "image/png" },
         m1: { kind: "sound", uri: "https://example.com/sound.ogg", mediaType: "audio/ogg" },

lib/account-state-manager.ts

@@ -0,0 +1,116 @@
+/**
+ * Manages per-account state snapshots for fast switching.
+ * When user switches from Account A → B, we snapshot A's store state
+ * into memory, clear stores, then restore B's cached state.
+ */
+
+import { useEmailStore } from '@/stores/email-store';
+import { useContactStore } from '@/stores/contact-store';
+import { useCalendarStore } from '@/stores/calendar-store';
+import { useFilterStore } from '@/stores/filter-store';
+import { useIdentityStore } from '@/stores/identity-store';
+import { useVacationStore } from '@/stores/vacation-store';
+
+// Minimal snapshot shapes — we only capture what we need
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+type StoreSnapshot = Record<string, any>;
+
+interface AccountSnapshot {
+  email: StoreSnapshot;
+  contact: StoreSnapshot;
+  calendar: StoreSnapshot;
+  filter: StoreSnapshot;
+  identity: StoreSnapshot;
+  vacation: StoreSnapshot;
+}
+
+const cache = new Map<string, AccountSnapshot>();
+
+/** Capture current store states for the given account */
+export function snapshotAccount(accountId: string): void {
+  const emailState = useEmailStore.getState();
+  const contactState = useContactStore.getState();
+  const calendarState = useCalendarStore.getState();
+  const filterState = useFilterStore.getState();
+  const identityState = useIdentityStore.getState();
+  const vacationState = useVacationStore.getState();
+
+  cache.set(accountId, {
+    email: {
+      emails: emailState.emails,
+      mailboxes: emailState.mailboxes,
+      selectedEmail: emailState.selectedEmail,
+      selectedMailbox: emailState.selectedMailbox,
+      searchQuery: emailState.searchQuery,
+      quota: emailState.quota,
+    },
+    contact: {
+      contacts: contactState.contacts,
+      addressBooks: contactState.addressBooks,
+      supportsSync: contactState.supportsSync,
+    },
+    calendar: {
+      calendars: calendarState.calendars,
+      events: calendarState.events,
+      selectedCalendarIds: calendarState.selectedCalendarIds,
+      viewMode: calendarState.viewMode,
+      supportsCalendar: calendarState.supportsCalendar,
+    },
+    filter: {
+      rules: filterState.rules,
+      isSupported: filterState.isSupported,
+    },
+    identity: {
+      identities: identityState.identities,
+      preferredPrimaryId: identityState.preferredPrimaryId,
+    },
+    vacation: {
+      isEnabled: vacationState.isEnabled,
+      isSupported: vacationState.isSupported,
+    },
+  });
+}
+
+/** Restore cached store states for the given account. Returns false if no cache exists. */
+export function restoreAccount(accountId: string): boolean {
+  const snapshot = cache.get(accountId);
+  if (!snapshot) return false;
+
+  useEmailStore.setState(snapshot.email);
+  useContactStore.setState(snapshot.contact);
+  useCalendarStore.setState(snapshot.calendar);
+  useFilterStore.setState(snapshot.filter);
+  useIdentityStore.setState(snapshot.identity);
+  useVacationStore.setState(snapshot.vacation);
+
+  return true;
+}
+
+/** Clear all stores (used before restoring a different account) */
+export function clearAllStores(): void {
+  useEmailStore.setState({
+    emails: [],
+    mailboxes: [],
+    selectedEmail: null,
+    selectedMailbox: '',
+    isLoading: false,
+    error: null,
+    searchQuery: '',
+    quota: null,
+  });
+  useIdentityStore.getState().clearIdentities();
+  useContactStore.getState().clearContacts();
+  useVacationStore.getState().clearState();
+  useCalendarStore.getState().clearState();
+  useFilterStore.getState().clearState();
+}
+
+/** Evict cached state for one account */
+export function evictAccount(accountId: string): void {
+  cache.delete(accountId);
+}
+
+/** Evict all cached states */
+export function evictAll(): void {
+  cache.clear();
+}

lib/account-utils.ts

@@ -0,0 +1,59 @@
+/**
+ * Utilities for multi-account support:
+ * - Account ID generation
+ * - Deterministic avatar colors
+ * - Account-scoped localStorage keys
+ */
+
+/** Generate a unique, deterministic account ID from username and server URL */
+export function generateAccountId(username: string, serverUrl: string): string {
+  const host = new URL(serverUrl).hostname;
+  return `${username}@${host}`;
+}
+
+/** Deterministic avatar/accent color from an email string */
+export function generateAvatarColor(email: string): string {
+  let hash = 0;
+  for (let i = 0; i < email.length; i++) {
+    hash = ((hash << 5) - hash + email.charCodeAt(i)) | 0;
+  }
+  // 12 distinct, accessible hues
+  const colors = [
+    '#2563eb', // blue
+    '#7c3aed', // violet
+    '#db2777', // pink
+    '#dc2626', // red
+    '#ea580c', // orange
+    '#d97706', // amber
+    '#65a30d', // lime
+    '#16a34a', // green
+    '#0d9488', // teal
+    '#0891b2', // cyan
+    '#6366f1', // indigo
+    '#9333ea', // purple
+  ];
+  return colors[Math.abs(hash) % colors.length];
+}
+
+/** Get initials for an avatar from a display name or email */
+export function getInitials(name: string, email?: string): string {
+  if (name) {
+    const parts = name.trim().split(/\s+/);
+    if (parts.length >= 2) {
+      return (parts[0][0] + parts[parts.length - 1][0]).toUpperCase();
+    }
+    return parts[0][0]?.toUpperCase() ?? '?';
+  }
+  if (email) {
+    return email[0]?.toUpperCase() ?? '?';
+  }
+  return '?';
+}
+
+/** Build an account-scoped localStorage key */
+export function getAccountScopedKey(baseKey: string, accountId: string): string {
+  return `${baseKey}::${accountId}`;
+}
+
+/** Maximum number of accounts allowed */
+export const MAX_ACCOUNTS = 5;

lib/auth/session-cookie.ts

@@ -1,2 +1,7 @@
 export const SESSION_COOKIE = 'jmap_session';
 export const SESSION_COOKIE_MAX_AGE = 30 * 24 * 60 * 60;
+
+/** Get the cookie name for a given account slot (0-4). Slot 0 uses the legacy name. */
+export function sessionCookieName(slot: number): string {
+  return slot === 0 ? SESSION_COOKIE : `${SESSION_COOKIE}_${slot}`;
+}

lib/browser-navigation.ts

@@ -0,0 +1,7 @@
+export function replaceWindowLocation(url: string): void {
+  if (typeof window === 'undefined') {
+    return;
+  }
+
+  window.location.replace(url);
+}

lib/calendar-invitation.ts

@@ -449,6 +449,7 @@ export interface EventSummary {
   title: string;
   start: string | null;
   end: string | null;
+  isAllDay: boolean;
   location: string | null;
   organizer: string | null;
   organizerEmail: string | null;
@@ -495,6 +496,8 @@ export function formatEventSummary(event: Partial<CalendarEvent>): EventSummary
     if (!organizer) organizer = organizerEmail;
   }
 
+  const isAllDay = event.showWithoutTime ?? false;
+
   let end: string | null = null;
   if (event.utcEnd) {
     end = event.utcEnd;
@@ -502,10 +505,17 @@ export function formatEventSummary(event: Partial<CalendarEvent>): EventSummary
     end = addDurationToDate(event.start, event.duration, event.timeZone);
   }
 
+  // For all-day events, prefer the local start (no timezone) to avoid
+  // UTC conversion shifting the displayed date in non-UTC timezones.
+  const start = isAllDay
+    ? (event.start || null)
+    : (event.utcStart || event.start || null);
+
   return {
     title: event.title || '',
-    start: event.utcStart || event.start || null,
+    start,
     end,
+    isAllDay,
     location,
     organizer,
     organizerEmail,
@@ -530,6 +540,19 @@ function addDurationToDate(start: string, duration: string, _timeZone?: string |
   date.setMinutes(date.getMinutes() + minutes);
   date.setSeconds(date.getSeconds() + seconds);
 
+  // If the input is a local datetime (no UTC 'Z' suffix), return a local
+  // format string so that all-day date arithmetic isn't shifted by the
+  // browser's UTC offset (toISOString converts to UTC).
+  if (!start.endsWith('Z') && !start.includes('+')) {
+    const y = date.getFullYear();
+    const m = String(date.getMonth() + 1).padStart(2, '0');
+    const d = String(date.getDate()).padStart(2, '0');
+    const h = String(date.getHours()).padStart(2, '0');
+    const min = String(date.getMinutes()).padStart(2, '0');
+    const s = String(date.getSeconds()).padStart(2, '0');
+    return `${y}-${m}-${d}T${h}:${min}:${s}`;
+  }
+
   return date.toISOString();
 }
 

lib/calendar-utils.ts

@@ -79,6 +79,8 @@ export function buildWeekSegments(events: CalendarEvent[], weekDays: Date[]): Ca
     if (left.event.showWithoutTime !== right.event.showWithoutTime) {
       return left.event.showWithoutTime ? -1 : 1;
     }
+    const timeDiff = new Date(left.event.start).getTime() - new Date(right.event.start).getTime();
+    if (timeDiff !== 0) return timeDiff;
     return (left.event.title || "").localeCompare(right.event.title || "");
   });
 
@@ -140,3 +142,7 @@ export function formatSnapTime(minutes: number, timeFormat: "12h" | "24h"): stri
   }
   return `${String(h).padStart(2, "0")}:${String(m).padStart(2, "0")}`;
 }
+
+export function getPrimaryCalendarId(event: Pick<CalendarEvent, 'calendarIds'>): string | undefined {
+  return Object.keys(event.calendarIds || {})[0];
+}

lib/jmap/types.ts

@@ -36,6 +36,9 @@ export interface Email {
     verdict: string;
     explanation: string;
   };
+  // S/MIME support
+  blobId?: string;
+  bodyStructure?: EmailBodyPart;
 }
 
 export interface AuthenticationResults {
@@ -157,9 +160,13 @@ export interface Identity {
 
 export interface ContactCard {
   id: string;
+  originalId?: string;
   uid?: string;
   addressBookIds: Record<string, boolean>;
   kind?: 'individual' | 'group' | 'org' | 'location' | 'device' | 'application';
+  accountId?: string;
+  accountName?: string;
+  isShared?: boolean;
   language?: string;
   name?: ContactName;
   nicknames?: Record<string, ContactNickname>;
@@ -180,7 +187,10 @@ export interface ContactCard {
   relatedTo?: Record<string, ContactRelation>;
   keywords?: Record<string, boolean>;
   members?: Record<string, boolean>;
-  gender?: { sex?: string; identity?: string };
+  speakToAs?: {
+    grammaticalGender?: string;
+    pronouns?: Record<string, { pronouns: string; pref?: number; contexts?: Record<string, boolean> }>;
+  };
   calendarUri?: string;
   schedulingUri?: string;
   freeBusyUri?: string;
@@ -242,7 +252,20 @@ export interface ContactTitle {
   organizationId?: string;
 }
 
+// RFC 9553 AddressComponent
+export interface AddressComponent {
+  kind: 'room' | 'apartment' | 'floor' | 'building' | 'number' | 'name' | 'block' | 'subDistrict' | 'district' | 'locality' | 'region' | 'postcode' | 'country' | 'direction' | 'landmark' | 'postOfficeBox' | 'separator' | string;
+  value: string;
+  phonetic?: string;
+}
+
 export interface ContactAddress {
+  // RFC 9553 format
+  components?: AddressComponent[];
+  full?: string;
+  isOrdered?: boolean;
+  defaultSeparator?: string;
+  // Legacy flat fields (from vCard import)
   street?: string;
   locality?: string;
   region?: string;
@@ -274,9 +297,27 @@ export interface ContactMedia {
   mediaType?: string;
 }
 
+// RFC 9553 PartialDate
+export interface PartialDate {
+  '@type'?: 'PartialDate';
+  year?: number;
+  month?: number;
+  day?: number;
+  calendarScale?: string;
+}
+
+// RFC 9553 Timestamp
+export interface Timestamp {
+  '@type': 'Timestamp';
+  utc: string;
+}
+
+export type AnniversaryDate = string | PartialDate | Timestamp;
+
 export interface ContactAnniversary {
+  '@type'?: 'Anniversary';
   kind: 'birth' | 'death' | 'wedding' | 'other';
-  date: string;
+  date: AnniversaryDate;
   place?: ContactAddress;
 }
 
@@ -313,12 +354,16 @@ export interface ContactRelation {
 
 export interface AddressBook {
   id: string;
+  originalId?: string;
   name: string;
   description?: string | null;
   sortOrder?: number;
   isDefault?: boolean;
   isSubscribed?: boolean;
   myRights?: AddressBookRights;
+  accountId?: string;
+  accountName?: string;
+  isShared?: boolean;
 }
 
 export interface AddressBookRights {
@@ -364,6 +409,7 @@ export interface DeliveryStatus {
 
 export interface Calendar {
   id: string;
+  originalId?: string;
   name: string;
   description: string | null;
   color: string | null;
@@ -377,6 +423,9 @@ export interface Calendar {
   timeZone: string | null;
   shareWith: Record<string, CalendarRights> | null;
   myRights: CalendarRights;
+  accountId?: string;
+  accountName?: string;
+  isShared?: boolean;
 }
 
 export interface CalendarRights {
@@ -392,7 +441,12 @@ export interface CalendarRights {
 
 export interface CalendarEvent {
   id: string;
+  originalId?: string;
   calendarIds: Record<string, boolean>;
+  originalCalendarIds?: Record<string, boolean>;
+  accountId?: string;
+  accountName?: string;
+  isShared?: boolean;
   isDraft: boolean;
   isOrigin: boolean;
   utcStart: string | null;
@@ -541,6 +595,32 @@ export interface CalendarRelation {
   relation: Record<string, boolean> | null;
 }
 
+export interface CalendarTask {
+  id: string;
+  calendarIds: Record<string, boolean>;
+  '@type': 'Task';
+  uid: string;
+  title: string;
+  description: string;
+  due: string | null;
+  start: string | null;
+  duration: string | null;
+  timeZone: string | null;
+  showWithoutTime: boolean;
+  progress: 'needs-action' | 'in-process' | 'completed' | 'cancelled';
+  progressUpdated: string | null;
+  priority: number;
+  privacy: 'public' | 'private' | 'secret';
+  keywords: Record<string, boolean> | null;
+  categories: Record<string, boolean> | null;
+  color: string | null;
+  created: string | null;
+  updated: string;
+  recurrenceRules: CalendarRecurrenceRule[] | null;
+  alerts: Record<string, CalendarEventAlert> | null;
+  relatedTo: Record<string, CalendarRelation> | null;
+}
+
 export interface CalendarParticipantIdentity {
   id: string;
   name: string;

lib/oauth/tokens.ts

@@ -1,2 +1,7 @@
 export const OAUTH_SCOPES = 'openid email profile';
 export const REFRESH_TOKEN_COOKIE = 'jmap_rt';
+
+/** Get the cookie name for a given account slot (0-4). Slot 0 uses the legacy name. */
+export function refreshTokenCookieName(slot: number): string {
+  return slot === 0 ? REFRESH_TOKEN_COOKIE : `${REFRESH_TOKEN_COOKIE}_${slot}`;
+}

lib/settings-sync.ts

@@ -1,5 +1,5 @@
 import { createHash, createCipheriv, createDecipheriv, randomBytes } from 'node:crypto';
-import { readFile, writeFile, unlink, mkdir } from 'node:fs/promises';
+import { readFile, writeFile, unlink, mkdir, rename } from 'node:fs/promises';
 import { existsSync } from 'node:fs';
 import path from 'node:path';
 import { logger } from '@/lib/logger';
@@ -45,7 +45,10 @@ export async function saveUserSettings(username: string, serverUrl: string, sett
   const tag = cipher.getAuthTag();
 
   const data = Buffer.concat([iv, tag, encrypted]);
-  await writeFile(getSettingsPath(username, serverUrl), data);
+  const targetPath = getSettingsPath(username, serverUrl);
+  const tmpPath = targetPath + '.tmp';
+  await writeFile(tmpPath, data);
+  await rename(tmpPath, targetPath);
 }
 
 export async function loadUserSettings(username: string, serverUrl: string): Promise<Record<string, unknown> | null> {

lib/signature-utils.ts

@@ -0,0 +1,158 @@
+import { parseHtmlSafely, sanitizeSignatureHtml } from '@/lib/email-sanitization';
+
+type SignatureSource = {
+  textSignature?: string;
+  htmlSignature?: string;
+};
+
+const BLOCK_TAGS = new Set([
+  'address',
+  'article',
+  'aside',
+  'blockquote',
+  'div',
+  'footer',
+  'header',
+  'li',
+  'nav',
+  'p',
+  'section',
+  'tr',
+]);
+
+function normalizeSignatureLineBreaks(value: string): string {
+  return value
+    .replace(/\r\n?/g, '\n')
+    .replace(/\u00a0/g, ' ')
+    .replace(/[ \t]+\n/g, '\n')
+    .replace(/\n{3,}/g, '\n\n')
+    .trim();
+}
+
+function htmlToPlainText(html: string): string {
+  const document = parseHtmlSafely(html);
+  const chunks: string[] = [];
+
+  const appendText = (value: string) => {
+    if (!value) return;
+    const normalized = value.replace(/\s+/g, ' ');
+    if (!normalized.trim()) return;
+    const previous = chunks[chunks.length - 1];
+    if (previous && !previous.endsWith('\n') && !previous.endsWith(' ')) {
+      chunks.push(' ');
+    }
+    chunks.push(normalized);
+  };
+
+  const appendNewline = () => {
+    const previous = chunks[chunks.length - 1];
+    if (previous === '\n') return;
+    if (previous?.endsWith('\n')) return;
+    chunks.push('\n');
+  };
+
+  const walk = (node: Node) => {
+    if (node.nodeType === Node.TEXT_NODE) {
+      appendText(node.textContent || '');
+      return;
+    }
+
+    if (node.nodeType !== Node.ELEMENT_NODE) {
+      return;
+    }
+
+    const element = node as HTMLElement;
+    const tagName = element.tagName.toLowerCase();
+
+    if (tagName === 'br') {
+      appendNewline();
+      return;
+    }
+
+    if (tagName === 'a') {
+      const text = element.textContent?.replace(/\s+/g, ' ').trim() || '';
+      const href = element.getAttribute('href')?.trim() || '';
+      const normalizedHref = href.replace(/^mailto:/i, '');
+      if (text && normalizedHref && text === normalizedHref) {
+        appendText(text);
+        return;
+      }
+      if (text && href && text !== href) {
+        appendText(`${text} <${href}>`);
+        return;
+      }
+    }
+
+    if (BLOCK_TAGS.has(tagName) && chunks.length > 0) {
+      appendNewline();
+    }
+
+    Array.from(element.childNodes).forEach(walk);
+
+    if (BLOCK_TAGS.has(tagName)) {
+      appendNewline();
+    }
+  };
+
+  Array.from(document.body.childNodes).forEach(walk);
+  return normalizeSignatureLineBreaks(chunks.join(''));
+}
+
+export function getPlainTextSignature(signature?: SignatureSource | null): string {
+  if (signature?.textSignature?.trim()) {
+    return normalizeSignatureLineBreaks(signature.textSignature);
+  }
+
+  if (signature?.htmlSignature?.trim()) {
+    return htmlToPlainText(sanitizeSignatureHtml(signature.htmlSignature));
+  }
+
+  return '';
+}
+
+export function appendPlainTextSignature(body: string, signature?: SignatureSource | null): string {
+  const plainTextSignature = getPlainTextSignature(signature);
+  if (!plainTextSignature) {
+    return body;
+  }
+
+  return `${body}\n\n-- \n${plainTextSignature}`;
+}
+
+export function hasMeaningfulHtmlBody(html: string): boolean {
+  if (!html.trim()) return false;
+
+  const document = parseHtmlSafely(html);
+  const richSelector = [
+    'table',
+    'img',
+    'style',
+    'b',
+    'strong',
+    'i',
+    'em',
+    'u',
+    'font',
+    'a[href]',
+    'div[style]',
+    'span[style]',
+    'p[style]',
+    'h1',
+    'h2',
+    'h3',
+    'h4',
+    'h5',
+    'h6',
+    'ul',
+    'ol',
+    'blockquote',
+    'br',
+  ].join(', ');
+
+  if (document.querySelector(richSelector)) {
+    return true;
+  }
+
+  const blockElements = document.body.querySelectorAll('p, div, blockquote, li');
+  return blockElements.length > 1;
+}

lib/smime/__tests__/certificate-utils.test.ts

@@ -0,0 +1,214 @@
+import { describe, it, expect, vi, beforeAll } from 'vitest';
+import {
+  pemToDer,
+  derToPem,
+  isPem,
+  parseCertificateDer,
+  parseCertificatePemOrDer,
+  computeFingerprint,
+  classifyCapabilities,
+  extractCertificateInfo,
+} from '../certificate-utils';
+import * as pkijs from 'pkijs';
+import * as asn1js from 'asn1js';
+
+// Generate a self-signed test certificate using Web Crypto + pkijs
+let testCertDer: ArrayBuffer;
+let testCert: pkijs.Certificate;
+let testKeyPair: globalThis.CryptoKeyPair;
+
+beforeAll(async () => {
+  const cryptoEngine = new pkijs.CryptoEngine({
+    crypto: crypto,
+    subtle: crypto.subtle,
+    name: 'webcrypto',
+  });
+  pkijs.setEngine('test', crypto, cryptoEngine);
+
+  // Generate RSA key pair
+  testKeyPair = await crypto.subtle.generateKey(
+    { name: 'RSASSA-PKCS1-v1_5', modulusLength: 2048, publicExponent: new Uint8Array([1, 0, 1]), hash: 'SHA-256' },
+    true,
+    ['sign', 'verify'],
+  );
+
+  // Build a minimal self-signed X.509 certificate
+  testCert = new pkijs.Certificate();
+  testCert.version = 2; // v3
+  testCert.serialNumber = new asn1js.Integer({ value: 1 });
+
+  testCert.issuer.typesAndValues.push(new pkijs.AttributeTypeAndValue({
+    type: '2.5.4.3', // CN
+    value: new asn1js.Utf8String({ value: 'Test CA' }),
+  }));
+
+  testCert.subject.typesAndValues.push(new pkijs.AttributeTypeAndValue({
+    type: '2.5.4.3', // CN
+    value: new asn1js.Utf8String({ value: 'Test User' }),
+  }));
+
+  testCert.subject.typesAndValues.push(new pkijs.AttributeTypeAndValue({
+    type: '1.2.840.113549.1.9.1', // emailAddress
+    value: new asn1js.IA5String({ value: 'test@example.com' }),
+  }));
+
+  testCert.notBefore.value = new Date('2024-01-01T00:00:00Z');
+  testCert.notAfter.value = new Date('2030-12-31T23:59:59Z');
+
+  await testCert.subjectPublicKeyInfo.importKey(testKeyPair.publicKey, cryptoEngine);
+
+  // Add KeyUsage extension: digitalSignature + keyEncipherment
+  const bitArray = new ArrayBuffer(1);
+  const bitView = new Uint8Array(bitArray);
+  bitView[0] = 0b10100000; // digitalSignature (bit 0) + keyEncipherment (bit 2)
+
+  testCert.extensions = [
+    new pkijs.Extension({
+      extnID: '2.5.29.15', // keyUsage
+      critical: true,
+      extnValue: new asn1js.OctetString({
+        valueHex: new Uint8Array(new asn1js.BitString({
+          valueHex: bitArray,
+          unusedBits: 3,
+        }).toBER(false)),
+      }).toBER(false) as ArrayBuffer,
+      parsedValue: {
+        digitalSignature: true,
+        contentCommitment: false,
+        keyEncipherment: true,
+        dataEncipherment: false,
+        keyAgreement: false,
+        keyCertSign: false,
+        cRLSign: false,
+        encipherOnly: false,
+        decipherOnly: false,
+      },
+    }),
+  ];
+
+  await testCert.sign(testKeyPair.privateKey, 'SHA-256', cryptoEngine);
+
+  // toBER may return a non-standard ArrayBuffer in jsdom; normalize it
+  const rawDer = testCert.toSchema(true).toBER(false);
+  testCertDer = new Uint8Array(rawDer).buffer;
+});
+
+describe('certificate-utils', () => {
+  describe('pemToDer / derToPem roundtrip', () => {
+    it('converts PEM to DER and back', () => {
+      const pem = derToPem(testCertDer, 'CERTIFICATE');
+      expect(pem).toContain('-----BEGIN CERTIFICATE-----');
+      expect(pem).toContain('-----END CERTIFICATE-----');
+
+      const der2 = pemToDer(pem);
+      expect(new Uint8Array(der2)).toEqual(new Uint8Array(testCertDer));
+    });
+
+    it('derToPem wraps lines at 64 chars', () => {
+      const pem = derToPem(testCertDer, 'CERTIFICATE');
+      const lines = pem.split('\n');
+      // All content lines (not headers) should be <= 64 chars
+      for (const line of lines) {
+        if (!line.startsWith('-----')) {
+          expect(line.length).toBeLessThanOrEqual(64);
+        }
+      }
+    });
+  });
+
+  describe('isPem', () => {
+    it('returns true for certificate PEM', () => {
+      expect(isPem('-----BEGIN CERTIFICATE-----\nMIIB...\n-----END CERTIFICATE-----')).toBe(true);
+    });
+
+    it('returns true for PKCS12 PEM', () => {
+      expect(isPem('-----BEGIN PKCS12-----\ndata\n-----END PKCS12-----')).toBe(true);
+    });
+
+    it('returns true for private key PEM', () => {
+      expect(isPem('-----BEGIN PRIVATE KEY-----\ndata\n-----END PRIVATE KEY-----')).toBe(true);
+    });
+
+    it('returns true for encrypted private key PEM', () => {
+      expect(isPem('-----BEGIN ENCRYPTED PRIVATE KEY-----\ndata\n-----END ENCRYPTED PRIVATE KEY-----')).toBe(true);
+    });
+
+    it('returns false for non-PEM data', () => {
+      expect(isPem('hello world')).toBe(false);
+      expect(isPem('')).toBe(false);
+      expect(isPem('MIIB...')).toBe(false);
+    });
+  });
+
+  describe('parseCertificateDer', () => {
+    it('parses a valid DER certificate', () => {
+      const cert = parseCertificateDer(testCertDer);
+      expect(cert).toBeInstanceOf(pkijs.Certificate);
+    });
+
+    it('throws on invalid DER data', () => {
+      const garbage = new Uint8Array([0, 1, 2, 3]).buffer;
+      expect(() => parseCertificateDer(garbage)).toThrow();
+    });
+  });
+
+  describe('parseCertificatePemOrDer', () => {
+    it('parses DER ArrayBuffer', () => {
+      const cert = parseCertificatePemOrDer(testCertDer);
+      expect(cert).toBeInstanceOf(pkijs.Certificate);
+    });
+
+    it('parses PEM string', () => {
+      const pem = derToPem(testCertDer, 'CERTIFICATE');
+      const cert = parseCertificatePemOrDer(pem);
+      expect(cert).toBeInstanceOf(pkijs.Certificate);
+    });
+
+    it('throws on non-PEM string', () => {
+      expect(() => parseCertificatePemOrDer('not a pem')).toThrow('String input is not PEM-encoded');
+    });
+  });
+
+  describe('computeFingerprint', () => {
+    it('returns hex fingerprint with colons', async () => {
+      const fp = await computeFingerprint(testCertDer);
+      expect(fp).toMatch(/^[0-9a-f]{2}(:[0-9a-f]{2}){31}$/);
+    });
+
+    it('is deterministic', async () => {
+      const fp1 = await computeFingerprint(testCertDer);
+      const fp2 = await computeFingerprint(testCertDer);
+      expect(fp1).toBe(fp2);
+    });
+  });
+
+  describe('classifyCapabilities', () => {
+    it('detects sign + encrypt from KeyUsage', () => {
+      const caps = classifyCapabilities(testCert);
+      expect(caps.canSign).toBe(true);
+      expect(caps.canEncrypt).toBe(true);
+    });
+  });
+
+  describe('extractCertificateInfo', () => {
+    it('extracts full certificate metadata', async () => {
+      const info = await extractCertificateInfo(testCert, testCertDer);
+
+      expect(info.subject).toContain('CN=Test User');
+      expect(info.issuer).toContain('CN=Test CA');
+      expect(info.notBefore).toBe('2024-01-01T00:00:00.000Z');
+      expect(info.notAfter).toBe('2030-12-31T23:59:59.000Z');
+      expect(info.fingerprint).toMatch(/^[0-9a-f]{2}(:[0-9a-f]{2}){31}$/);
+      expect(info.algorithm).toMatch(/^RSA/);
+      expect(info.emailAddresses).toContain('test@example.com');
+      expect(info.capabilities.canSign).toBe(true);
+      expect(info.capabilities.canEncrypt).toBe(true);
+    });
+
+    it('returns serialNumber as hex', async () => {
+      const info = await extractCertificateInfo(testCert, testCertDer);
+      // Serial number 1 → should be hex string
+      expect(info.serialNumber).toBeTruthy();
+    });
+  });
+});

lib/smime/__tests__/key-storage.test.ts

@@ -0,0 +1,151 @@
+import { describe, it, expect, beforeEach, vi } from 'vitest';
+import 'fake-indexeddb/auto';
+
+// Each test file gets a fresh global indexedDB via fake-indexeddb/auto.
+// Since openDB() caches connections implicitly, we re-import the module for each test.
+// However, to keep it simple, we'll just test in order and accept cumulative state,
+// or we can test with unique IDs.
+
+import {
+  saveKeyRecord,
+  getKeyRecord,
+  getKeyRecordForEmail,
+  listKeyRecords,
+  deleteKeyRecord,
+  savePublicCert,
+  getPublicCertForEmail,
+  listPublicCerts,
+  deletePublicCert,
+} from '../key-storage';
+import type { SmimeKeyRecord, SmimePublicCert } from '../types';
+
+function makeKeyRecord(overrides: Partial<SmimeKeyRecord> = {}): SmimeKeyRecord {
+  return {
+    id: 'key-1',
+    email: 'user@example.com',
+    certificate: new ArrayBuffer(10),
+    certificateChain: [],
+    encryptedPrivateKey: new ArrayBuffer(32),
+    salt: new ArrayBuffer(16),
+    iv: new ArrayBuffer(12),
+    kdfIterations: 600000,
+    issuer: 'CN=Test CA',
+    subject: 'CN=Test User',
+    serialNumber: '01',
+    notBefore: '2024-01-01T00:00:00Z',
+    notAfter: '2030-12-31T23:59:59Z',
+    fingerprint: 'aa:bb:cc',
+    algorithm: 'RSA-2048',
+    capabilities: { canSign: true, canEncrypt: true },
+    ...overrides,
+  };
+}
+
+function makePublicCert(overrides: Partial<SmimePublicCert> = {}): SmimePublicCert {
+  return {
+    id: 'cert-1',
+    email: 'recipient@example.com',
+    certificate: new ArrayBuffer(10),
+    issuer: 'CN=Test CA',
+    subject: 'CN=Recipient',
+    notBefore: '2024-01-01T00:00:00Z',
+    notAfter: '2030-12-31T23:59:59Z',
+    fingerprint: 'dd:ee:ff',
+    source: 'manual',
+    ...overrides,
+  };
+}
+
+// Use unique IDs for each test to avoid state leakage
+let testCounter = 0;
+function uid() { return `test-${++testCounter}-${Date.now()}`; }
+
+describe('key-storage', () => {
+  describe('key records', () => {
+    it('saves and retrieves a key record by id', async () => {
+      const id = uid();
+      const record = makeKeyRecord({ id });
+      await saveKeyRecord(record);
+      const retrieved = await getKeyRecord(id);
+      expect(retrieved).toBeDefined();
+      expect(retrieved!.id).toBe(id);
+      expect(retrieved!.email).toBe('user@example.com');
+    });
+
+    it('returns undefined for non-existent key record', async () => {
+      const result = await getKeyRecord('absolutely-non-existent-' + uid());
+      expect(result).toBeUndefined();
+    });
+
+    it('retrieves key record by email', async () => {
+      const id = uid();
+      const email = `alice-${id}@example.com`;
+      const record = makeKeyRecord({ id, email });
+      await saveKeyRecord(record);
+      const result = await getKeyRecordForEmail(email);
+      expect(result).toBeDefined();
+      expect(result!.email).toBe(email);
+    });
+
+    it('lists key records (includes previously saved)', async () => {
+      const id1 = uid();
+      const id2 = uid();
+      await saveKeyRecord(makeKeyRecord({ id: id1, email: `${id1}@example.com` }));
+      await saveKeyRecord(makeKeyRecord({ id: id2, email: `${id2}@example.com` }));
+      const records = await listKeyRecords();
+      expect(records.length).toBeGreaterThanOrEqual(2);
+      expect(records.find(r => r.id === id1)).toBeDefined();
+      expect(records.find(r => r.id === id2)).toBeDefined();
+    });
+
+    it('deletes a key record', async () => {
+      const id = uid();
+      const record = makeKeyRecord({ id });
+      await saveKeyRecord(record);
+      await deleteKeyRecord(id);
+      const result = await getKeyRecord(id);
+      expect(result).toBeUndefined();
+    });
+
+    it('updates existing record with same id', async () => {
+      const id = uid();
+      const record1 = makeKeyRecord({ id, email: 'old@example.com' });
+      await saveKeyRecord(record1);
+      const record2 = makeKeyRecord({ id, email: 'new@example.com' });
+      await saveKeyRecord(record2);
+      const retrieved = await getKeyRecord(id);
+      expect(retrieved!.email).toBe('new@example.com');
+    });
+  });
+
+  describe('public certs', () => {
+    it('saves and retrieves by email', async () => {
+      const id = uid();
+      const email = `recipient-${id}@example.com`;
+      const cert = makePublicCert({ id, email });
+      await savePublicCert(cert);
+      const result = await getPublicCertForEmail(email);
+      expect(result).toBeDefined();
+      expect(result!.email).toBe(email);
+    });
+
+    it('lists public certs (includes previously saved)', async () => {
+      const id1 = uid();
+      const id2 = uid();
+      await savePublicCert(makePublicCert({ id: id1, email: `${id1}@test.com` }));
+      await savePublicCert(makePublicCert({ id: id2, email: `${id2}@test.com` }));
+      const certs = await listPublicCerts();
+      expect(certs.find(c => c.id === id1)).toBeDefined();
+      expect(certs.find(c => c.id === id2)).toBeDefined();
+    });
+
+    it('deletes a public cert', async () => {
+      const id = uid();
+      const cert = makePublicCert({ id });
+      await savePublicCert(cert);
+      await deletePublicCert(id);
+      const certs = await listPublicCerts();
+      expect(certs.find(c => c.id === id)).toBeUndefined();
+    });
+  });
+});

lib/smime/__tests__/mime-builder.test.ts

@@ -0,0 +1,259 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { buildMimeMessage, quotedPrintableEncode, base64Encode } from '../mime-builder';
+
+// Mock crypto.randomUUID and crypto.getRandomValues for deterministic tests
+beforeEach(() => {
+  let uuidCounter = 0;
+  vi.spyOn(crypto, 'randomUUID').mockImplementation(
+    () => `00000000-0000-0000-0000-${String(++uuidCounter).padStart(12, '0')}` as `${string}-${string}-${string}-${string}-${string}`,
+  );
+
+  vi.spyOn(crypto, 'getRandomValues').mockImplementation(<T extends ArrayBufferView | null>(array: T): T => {
+    if (array) {
+      const u8 = new Uint8Array((array as unknown as Uint8Array).buffer);
+      for (let i = 0; i < u8.length; i++) u8[i] = i;
+    }
+    return array;
+  });
+});
+
+describe('mime-builder', () => {
+  describe('buildMimeMessage', () => {
+    it('builds a text-only message', () => {
+      const msg = buildMimeMessage({
+        from: { name: 'Alice', email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        subject: 'Hello',
+        textBody: 'Hi Bob!',
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('From: "Alice" <alice@example.com>');
+      expect(text).toContain('To: bob@example.com');
+      expect(text).toContain('Subject: Hello');
+      expect(text).toContain('Content-Type: text/plain; charset=utf-8');
+      expect(text).toContain('MIME-Version: 1.0');
+      expect(text).toContain('Hi Bob!');
+    });
+
+    it('builds a text + HTML multipart/alternative', () => {
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        subject: 'Test',
+        textBody: 'Plain text',
+        htmlBody: '<p>HTML body</p>',
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('Content-Type: multipart/alternative');
+      expect(text).toContain('Content-Type: text/plain; charset=utf-8');
+      expect(text).toContain('Content-Type: text/html; charset=utf-8');
+      expect(text).toContain('Plain text');
+      expect(text).toContain('<p>HTML body</p>');
+    });
+
+    it('builds HTML-only message', () => {
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        subject: 'HTML only',
+        htmlBody: '<h1>Hello</h1>',
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('Content-Type: text/html; charset=utf-8');
+      expect(text).toContain('<h1>Hello</h1>');
+    });
+
+    it('builds message with attachments', () => {
+      const attachment = {
+        filename: 'test.txt',
+        contentType: 'text/plain',
+        content: new TextEncoder().encode('file content').buffer,
+      };
+
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        subject: 'With attachment',
+        textBody: 'See attached',
+        attachments: [attachment],
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('Content-Type: multipart/mixed');
+      expect(text).toContain('Content-Disposition: attachment; filename="test.txt"');
+      expect(text).toContain('Content-Transfer-Encoding: base64');
+    });
+
+    it('builds message with inline attachment (cid)', () => {
+      const inline = {
+        filename: 'image.png',
+        contentType: 'image/png',
+        content: new Uint8Array([0x89, 0x50, 0x4E, 0x47]).buffer,
+        cid: 'img1',
+      };
+
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        subject: 'Inline',
+        htmlBody: '<img src="cid:img1">',
+        attachments: [inline],
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('Content-Disposition: inline; filename="image.png"');
+      expect(text).toContain('Content-ID: <img1>');
+    });
+
+    it('includes CC header when provided', () => {
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        cc: [{ name: 'Charlie', email: 'charlie@example.com' }],
+        subject: 'CC test',
+        textBody: 'Hello',
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('Cc: "Charlie" <charlie@example.com>');
+    });
+
+    it('omits BCC from MIME headers', () => {
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        bcc: [{ email: 'secret@example.com' }],
+        subject: 'BCC test',
+        textBody: 'Hello',
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).not.toContain('Bcc');
+      expect(text).not.toContain('secret@example.com');
+    });
+
+    it('includes In-Reply-To and References', () => {
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        subject: 'Re: Thread',
+        textBody: 'reply',
+        inReplyTo: '<msg1@example.com>',
+        references: ['<msg0@example.com>', '<msg1@example.com>'],
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('In-Reply-To: <msg1@example.com>');
+      expect(text).toContain('References: <msg0@example.com> <msg1@example.com>');
+    });
+
+    it('encodes non-ASCII subject with RFC 2047', () => {
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        subject: 'Ünïcödé',
+        textBody: 'test',
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('=?UTF-8?Q?');
+    });
+
+    it('uses CRLF line endings', () => {
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        subject: 'CRLF',
+        textBody: 'test',
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      // Should contain CRLF before the body
+      expect(text).toContain('\r\n');
+      // Should not contain bare LF without preceding CR (except within QP encoding)
+      const lines = text.split('\r\n');
+      expect(lines.length).toBeGreaterThan(1);
+    });
+
+    it('builds empty body message', () => {
+      const msg = buildMimeMessage({
+        from: { email: 'alice@example.com' },
+        to: [{ email: 'bob@example.com' }],
+        subject: 'Empty',
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('Content-Type: text/plain; charset=utf-8');
+    });
+
+    it('escapes display name in From header', () => {
+      const msg = buildMimeMessage({
+        from: { name: 'O\'Brien, "Bob"', email: 'bob@example.com' },
+        to: [{ email: 'alice@example.com' }],
+        subject: 'Name test',
+        textBody: 'test',
+        date: new Date('2024-06-15T12:00:00Z'),
+      });
+
+      const text = new TextDecoder().decode(msg);
+      expect(text).toContain('From: "O\'Brien, \\"Bob\\"" <bob@example.com>');
+    });
+  });
+
+  describe('quotedPrintableEncode', () => {
+    it('passes through ASCII text unchanged', () => {
+      const result = quotedPrintableEncode('Hello World');
+      expect(result).toBe('Hello World');
+    });
+
+    it('encodes non-ASCII characters', () => {
+      const result = quotedPrintableEncode('Héllo');
+      expect(result).toContain('=');
+    });
+
+    it('encodes equals sign', () => {
+      const result = quotedPrintableEncode('a=b');
+      expect(result).toContain('=3D');
+    });
+
+    it('wraps long lines with soft line break', () => {
+      const longLine = 'a'.repeat(100);
+      const result = quotedPrintableEncode(longLine);
+      const lines = result.split('\r\n');
+      for (const line of lines) {
+        expect(line.length).toBeLessThanOrEqual(76);
+      }
+    });
+  });
+
+  describe('base64Encode', () => {
+    it('encodes binary data to base64', () => {
+      const data = new Uint8Array([72, 101, 108, 108, 111]).buffer; // "Hello"
+      const result = base64Encode(data);
+      expect(result).toBe('SGVsbG8=');
+    });
+
+    it('wraps long lines at 76 chars', () => {
+      const data = new Uint8Array(200).buffer;
+      const result = base64Encode(data);
+      const lines = result.split('\r\n');
+      for (const line of lines) {
+        expect(line.length).toBeLessThanOrEqual(76);
+      }
+    });
+  });
+});

lib/smime/__tests__/pkcs12.test.ts

@@ -0,0 +1,219 @@
+// @vitest-environment node
+import { describe, it, expect, beforeAll } from 'vitest';
+import * as pkijs from 'pkijs';
+import * as asn1js from 'asn1js';
+import { importPkcs12, unlockPrivateKey, decryptPrivateKeyBytes } from '../pkcs12-import';
+import { exportPkcs12 } from '../pkcs12-export';
+
+const cryptoEngine = new pkijs.CryptoEngine({
+  crypto: crypto,
+  subtle: crypto.subtle,
+  name: 'webcrypto',
+});
+
+function stringToAB(str: string): ArrayBuffer {
+  const buf = new ArrayBuffer(str.length);
+  const view = new Uint8Array(buf);
+  for (let i = 0; i < str.length; i++) {
+    view[i] = str.charCodeAt(i);
+  }
+  return buf;
+}
+
+/**
+ * Build a minimal real PKCS#12 (.p12) blob for testing.
+ */
+async function buildTestP12(
+  email: string,
+  cn: string,
+  p12Password: string,
+): Promise<{ p12Bytes: ArrayBuffer; keyPair: globalThis.CryptoKeyPair; certDer: ArrayBuffer }> {
+  // Generate RSA key pair (signing)
+  const keyPair = await crypto.subtle.generateKey(
+    {
+      name: 'RSASSA-PKCS1-v1_5',
+      modulusLength: 2048,
+      publicExponent: new Uint8Array([1, 0, 1]),
+      hash: 'SHA-256',
+    },
+    true,
+    ['sign', 'verify'],
+  );
+
+  // Self-signed certificate
+  const cert = new pkijs.Certificate();
+  cert.version = 2;
+  cert.serialNumber = new asn1js.Integer({ value: 42 });
+
+  cert.issuer.typesAndValues.push(
+    new pkijs.AttributeTypeAndValue({
+      type: '2.5.4.3',
+      value: new asn1js.Utf8String({ value: cn }),
+    }),
+  );
+  cert.subject.typesAndValues.push(
+    new pkijs.AttributeTypeAndValue({
+      type: '2.5.4.3',
+      value: new asn1js.Utf8String({ value: cn }),
+    }),
+  );
+  cert.subject.typesAndValues.push(
+    new pkijs.AttributeTypeAndValue({
+      type: '1.2.840.113549.1.9.1',
+      value: new asn1js.IA5String({ value: email }),
+    }),
+  );
+  cert.notBefore.value = new Date('2024-01-01T00:00:00Z');
+  cert.notAfter.value = new Date('2030-12-31T23:59:59Z');
+
+  await cert.subjectPublicKeyInfo.importKey(keyPair.publicKey, cryptoEngine);
+  await cert.sign(keyPair.privateKey, 'SHA-256', cryptoEngine);
+
+  const certDer = cert.toSchema(true).toBER(false);
+
+  // Export private key as PKCS#8
+  const pkcs8Bytes = await crypto.subtle.exportKey('pkcs8', keyPair.privateKey);
+
+  // Build PKCS#12 structure
+  const keyBag = new pkijs.PKCS8ShroudedKeyBag({
+    parsedValue: pkijs.PrivateKeyInfo.fromBER(pkcs8Bytes),
+  });
+
+  const passwordBuf = stringToAB(p12Password);
+
+  await keyBag.makeInternalValues({
+    password: passwordBuf,
+    contentEncryptionAlgorithm: {
+      name: 'AES-CBC',
+      length: 256,
+    } as Parameters<typeof keyBag.makeInternalValues>[0]['contentEncryptionAlgorithm'],
+    hmacHashAlgorithm: 'SHA-256',
+    iterationCount: 2048,
+  });
+
+  const keyBagSafe = new pkijs.SafeBag({
+    bagId: '1.2.840.113549.1.12.10.1.2',
+    bagValue: keyBag,
+  });
+
+  const certBagSafe = new pkijs.SafeBag({
+    bagId: '1.2.840.113549.1.12.10.1.3',
+    bagValue: new pkijs.CertBag({ parsedValue: cert }),
+  });
+
+  const authenticatedSafe = new pkijs.AuthenticatedSafe({
+    parsedValue: {
+      safeContents: [
+        { privacyMode: 0, value: new pkijs.SafeContents({ safeBags: [keyBagSafe] }) },
+        { privacyMode: 0, value: new pkijs.SafeContents({ safeBags: [certBagSafe] }) },
+      ],
+    },
+  });
+
+  await authenticatedSafe.makeInternalValues({ safeContents: [{}, {}] });
+
+  const pfx = new pkijs.PFX({
+    parsedValue: {
+      integrityMode: 0,
+      authenticatedSafe,
+    },
+  });
+
+  await pfx.makeInternalValues({
+    password: passwordBuf,
+    iterations: 2048,
+    pbkdf2HashAlgorithm: 'SHA-256',
+    hmacHashAlgorithm: 'SHA-256',
+  });
+
+  const p12Bytes = pfx.toSchema().toBER(false);
+  return { p12Bytes, keyPair, certDer };
+}
+
+let testP12: Awaited<ReturnType<typeof buildTestP12>>;
+
+beforeAll(async () => {
+  pkijs.setEngine('test', crypto, cryptoEngine);
+  testP12 = await buildTestP12('alice@example.com', 'Alice Test', 'p12pass');
+});
+
+describe('importPkcs12', () => {
+  it('imports a valid PKCS#12 file and produces a key record', async () => {
+    const result = await importPkcs12(testP12.p12Bytes, 'p12pass', 'storagepass');
+
+    expect(result.keyRecord).toBeDefined();
+    expect(result.keyRecord.email).toBe('alice@example.com');
+    expect(result.keyRecord.subject).toContain('Alice Test');
+    expect(result.keyRecord.certificate).toBeDefined();
+    expect(result.keyRecord.encryptedPrivateKey.byteLength).toBeGreaterThan(0);
+    expect(result.keyRecord.salt.byteLength).toBeGreaterThan(0);
+    expect(result.keyRecord.iv.byteLength).toBeGreaterThan(0);
+    expect(result.keyRecord.kdfIterations).toBe(600_000);
+    expect(result.keyRecord.fingerprint).toBeTruthy();
+
+    expect(result.certInfo).toBeDefined();
+    expect(result.certInfo.emailAddresses).toContain('alice@example.com');
+  });
+
+  it('throws on invalid ASN.1 data', async () => {
+    const garbage = new Uint8Array([0, 1, 2, 3]).buffer;
+    await expect(importPkcs12(garbage, 'pass', 'store')).rejects.toThrow();
+  });
+});
+
+describe('unlockPrivateKey', () => {
+  it('unlocks and returns signing and decryption keys', async () => {
+    const result = await importPkcs12(testP12.p12Bytes, 'p12pass', 'storagepass');
+    const { signingKey, decryptionKey } = await unlockPrivateKey(result.keyRecord, 'storagepass');
+
+    expect(signingKey).toBeDefined();
+    expect(signingKey.type).toBe('private');
+    expect(signingKey.extractable).toBe(false);
+
+    expect(decryptionKey).toBeDefined();
+    expect(decryptionKey!.type).toBe('private');
+    expect(decryptionKey!.extractable).toBe(false);
+  });
+
+  it('throws on incorrect passphrase', async () => {
+    const result = await importPkcs12(testP12.p12Bytes, 'p12pass', 'storagepass');
+    await expect(unlockPrivateKey(result.keyRecord, 'wrongpass')).rejects.toThrow('Incorrect passphrase');
+  });
+});
+
+describe('decryptPrivateKeyBytes', () => {
+  it('returns raw PKCS#8 bytes', async () => {
+    const result = await importPkcs12(testP12.p12Bytes, 'p12pass', 'storagepass');
+    const pkcs8 = await decryptPrivateKeyBytes(result.keyRecord, 'storagepass');
+
+    expect(pkcs8).toBeInstanceOf(ArrayBuffer);
+    expect(pkcs8.byteLength).toBeGreaterThan(0);
+  });
+
+  it('throws on incorrect passphrase', async () => {
+    const result = await importPkcs12(testP12.p12Bytes, 'p12pass', 'storagepass');
+    await expect(decryptPrivateKeyBytes(result.keyRecord, 'bad')).rejects.toThrow('Incorrect passphrase');
+  });
+});
+
+describe('exportPkcs12', () => {
+  it('produces a valid PKCS#12 that can be re-imported', async () => {
+    const imported = await importPkcs12(testP12.p12Bytes, 'p12pass', 'storagepass');
+
+    // Export
+    const p12Out = await exportPkcs12(imported.keyRecord, 'storagepass', 'exportpass');
+    expect(p12Out).toBeInstanceOf(ArrayBuffer);
+    expect(p12Out.byteLength).toBeGreaterThan(0);
+
+    // Re-import
+    const reimported = await importPkcs12(p12Out, 'exportpass', 'newstoragepass');
+    expect(reimported.keyRecord.email).toBe('alice@example.com');
+    expect(reimported.keyRecord.subject).toContain('Alice Test');
+    expect(reimported.keyRecord.fingerprint).toBe(imported.keyRecord.fingerprint);
+  });
+
+  it('throws on incorrect storage passphrase', async () => {
+    const imported = await importPkcs12(testP12.p12Bytes, 'p12pass', 'storagepass');
+    await expect(exportPkcs12(imported.keyRecord, 'wrong', 'exportpass')).rejects.toThrow('Incorrect passphrase');
+  });
+});

lib/smime/__tests__/smime-crypto.test.ts

@@ -0,0 +1,342 @@
+// @vitest-environment node
+import { describe, it, expect, beforeAll } from 'vitest';
+import * as pkijs from 'pkijs';
+import * as asn1js from 'asn1js';
+import { smimeSign } from '../smime-sign';
+import { smimeEncrypt } from '../smime-encrypt';
+import { smimeDecrypt, SmimeKeyLockedError, findDecryptionCandidates, normalizeCmsBytes } from '../smime-decrypt';
+import { smimeVerify } from '../smime-verify';
+import { extractCertificateInfo } from '../certificate-utils';
+import type { SmimeKeyRecord } from '../types';
+
+/**
+ * Integration tests for S/MIME sign→verify and encrypt→decrypt roundtrips.
+ * Uses Node.js crypto (not jsdom) for accurate Web Crypto behavior.
+ */
+
+const testMimeBytes = new TextEncoder().encode(
+  'Content-Type: text/plain; charset=utf-8\r\n\r\nHello, World!',
+);
+
+const cryptoEngine = new pkijs.CryptoEngine({
+  crypto: crypto,
+  subtle: crypto.subtle,
+  name: 'webcrypto',
+});
+
+async function buildCert(
+  cn: string,
+  email: string,
+  publicKey: CryptoKey,
+  signingPrivateKey: CryptoKey,
+): Promise<{ cert: pkijs.Certificate; certDer: ArrayBuffer }> {
+  const cert = new pkijs.Certificate();
+  cert.version = 2;
+  cert.serialNumber = new asn1js.Integer({ value: Math.floor(Math.random() * 100000) });
+
+  cert.issuer.typesAndValues.push(
+    new pkijs.AttributeTypeAndValue({
+      type: '2.5.4.3',
+      value: new asn1js.Utf8String({ value: cn }),
+    }),
+  );
+  cert.subject.typesAndValues.push(
+    new pkijs.AttributeTypeAndValue({
+      type: '2.5.4.3',
+      value: new asn1js.Utf8String({ value: cn }),
+    }),
+  );
+  cert.subject.typesAndValues.push(
+    new pkijs.AttributeTypeAndValue({
+      type: '1.2.840.113549.1.9.1',
+      value: new asn1js.IA5String({ value: email }),
+    }),
+  );
+  cert.notBefore.value = new Date('2024-01-01T00:00:00Z');
+  cert.notAfter.value = new Date('2030-12-31T23:59:59Z');
+
+  await cert.subjectPublicKeyInfo.importKey(publicKey, cryptoEngine);
+
+  await cert.sign(signingPrivateKey, 'SHA-256', cryptoEngine);
+
+  const certDer = cert.toSchema(true).toBER(false);
+  return { cert, certDer };
+}
+
+async function makeKeyRecord(
+  id: string,
+  email: string,
+  certDer: ArrayBuffer,
+): Promise<SmimeKeyRecord> {
+  const cert = new pkijs.Certificate({
+    schema: asn1js.fromBER(certDer).result,
+  });
+  const info = await extractCertificateInfo(cert, certDer);
+  return {
+    id,
+    email: email.toLowerCase(),
+    certificate: certDer,
+    certificateChain: [],
+    encryptedPrivateKey: new ArrayBuffer(0),
+    salt: new ArrayBuffer(0),
+    iv: new ArrayBuffer(0),
+    kdfIterations: 600000,
+    issuer: info.issuer,
+    subject: info.subject,
+    serialNumber: info.serialNumber,
+    notBefore: info.notBefore,
+    notAfter: info.notAfter,
+    fingerprint: info.fingerprint,
+    algorithm: info.algorithm,
+    capabilities: info.capabilities,
+  };
+}
+
+// Signing key pair and cert (RSASSA-PKCS1-v1_5 public key embedded in cert)
+let signKeyPair: globalThis.CryptoKeyPair;
+let signCertDer: ArrayBuffer;
+
+// Encryption key pair and cert (RSA-OAEP public key embedded in cert)
+let encKeyPair: globalThis.CryptoKeyPair;
+let encCertDer: ArrayBuffer;
+let encKeyRecord: SmimeKeyRecord;
+
+// Second encryption identity for cross-recipient tests
+let bobEncKeyPair: globalThis.CryptoKeyPair;
+let bobEncCertDer: ArrayBuffer;
+let bobKeyRecord: SmimeKeyRecord;
+
+beforeAll(async () => {
+  pkijs.setEngine('test', crypto, cryptoEngine);
+
+  // --- Signing identity ---
+  signKeyPair = await crypto.subtle.generateKey(
+    { name: 'RSASSA-PKCS1-v1_5', modulusLength: 2048, publicExponent: new Uint8Array([1, 0, 1]), hash: 'SHA-256' },
+    true,
+    ['sign', 'verify'],
+  );
+  const signResult = await buildCert('Alice Signer', 'alice@example.com', signKeyPair.publicKey, signKeyPair.privateKey);
+  signCertDer = signResult.certDer;
+
+  // --- Encryption identity (Alice) ---
+  encKeyPair = await crypto.subtle.generateKey(
+    { name: 'RSA-OAEP', modulusLength: 2048, publicExponent: new Uint8Array([1, 0, 1]), hash: 'SHA-256' },
+    true,
+    ['encrypt', 'decrypt', 'wrapKey', 'unwrapKey'],
+  );
+  // Self-sign with a temporary signing key
+  const tempSignKey = await crypto.subtle.generateKey(
+    { name: 'RSASSA-PKCS1-v1_5', modulusLength: 2048, publicExponent: new Uint8Array([1, 0, 1]), hash: 'SHA-256' },
+    true,
+    ['sign', 'verify'],
+  );
+  const encResult = await buildCert('Alice', 'alice@example.com', encKeyPair.publicKey, tempSignKey.privateKey);
+  encCertDer = encResult.certDer;
+  encKeyRecord = await makeKeyRecord('key-alice-enc', 'alice@example.com', encCertDer);
+
+  // --- Bob encryption identity ---
+  bobEncKeyPair = await crypto.subtle.generateKey(
+    { name: 'RSA-OAEP', modulusLength: 2048, publicExponent: new Uint8Array([1, 0, 1]), hash: 'SHA-256' },
+    true,
+    ['encrypt', 'decrypt', 'wrapKey', 'unwrapKey'],
+  );
+  const bobTempSignKey = await crypto.subtle.generateKey(
+    { name: 'RSASSA-PKCS1-v1_5', modulusLength: 2048, publicExponent: new Uint8Array([1, 0, 1]), hash: 'SHA-256' },
+    true,
+    ['sign', 'verify'],
+  );
+  const bobResult = await buildCert('Bob', 'bob@example.com', bobEncKeyPair.publicKey, bobTempSignKey.privateKey);
+  bobEncCertDer = bobResult.certDer;
+  bobKeyRecord = await makeKeyRecord('key-bob-enc', 'bob@example.com', bobEncCertDer);
+});
+
+describe('smimeSign + smimeVerify roundtrip', () => {
+  it('signs and verifies a message successfully', async () => {
+    const signedBlob = await smimeSign(testMimeBytes, signKeyPair.privateKey, signCertDer);
+    expect(signedBlob).toBeInstanceOf(Blob);
+    expect(signedBlob.type).toContain('application/pkcs7-mime');
+
+    const cmsBytes = await signedBlob.arrayBuffer();
+    const result = await smimeVerify(cmsBytes, 'alice@example.com');
+
+    expect(result.status.isSigned).toBe(true);
+    expect(result.status.signatureValid).toBe(true);
+    expect(result.status.signerEmailMatch).toBe(true);
+    expect(result.status.signerCert).toBeDefined();
+    expect(result.status.signerCert!.email).toBe('alice@example.com');
+
+    const innerText = new TextDecoder().decode(result.mimeBytes);
+    expect(innerText).toContain('Hello, World!');
+  });
+
+  it('reports email mismatch when From differs from signer', async () => {
+    const signedBlob = await smimeSign(testMimeBytes, signKeyPair.privateKey, signCertDer);
+    const cmsBytes = await signedBlob.arrayBuffer();
+    const result = await smimeVerify(cmsBytes, 'evil@attacker.com');
+
+    expect(result.status.isSigned).toBe(true);
+    expect(result.status.signerEmailMatch).toBe(false);
+  });
+});
+
+describe('smimeEncrypt + smimeDecrypt roundtrip', () => {
+  it('encrypts and decrypts a message', async () => {
+    const encryptedBlob = await smimeEncrypt(
+      testMimeBytes,
+      [encCertDer],
+      encCertDer,
+    );
+    expect(encryptedBlob).toBeInstanceOf(Blob);
+    expect(encryptedBlob.type).toContain('application/pkcs7-mime');
+
+    const cmsBytes = await encryptedBlob.arrayBuffer();
+    const unlockedKeys = new Map<string, CryptoKey>();
+    unlockedKeys.set(encKeyRecord.id, encKeyPair.privateKey);
+
+    const result = await smimeDecrypt({
+      cmsBytes,
+      keyRecords: [encKeyRecord],
+      unlockedKeys,
+    });
+
+    expect(result.mimeBytes).toBeDefined();
+    const decryptedText = new TextDecoder().decode(result.mimeBytes);
+    expect(decryptedText).toContain('Hello, World!');
+    expect(result.keyRecordId).toBe(encKeyRecord.id);
+  });
+
+  it('throws when no matching key is available', async () => {
+    const encryptedBlob = await smimeEncrypt(
+      testMimeBytes,
+      [encCertDer],
+      encCertDer,
+    );
+    const cmsBytes = await encryptedBlob.arrayBuffer();
+
+    // Bob's key record doesn't match Alice's encrypted message
+    await expect(
+      smimeDecrypt({
+        cmsBytes,
+        keyRecords: [bobKeyRecord],
+        unlockedKeys: new Map(),
+      }),
+    ).rejects.toThrow('No imported S/MIME key matches');
+  });
+});
+
+describe('SmimeKeyLockedError', () => {
+  it('has correct name and keyRecordId', () => {
+    const err = new SmimeKeyLockedError('test', 'key-1');
+    expect(err.name).toBe('SmimeKeyLockedError');
+    expect(err.keyRecordId).toBe('key-1');
+    expect(err.message).toBe('test');
+    expect(err).toBeInstanceOf(Error);
+  });
+});
+
+describe('findDecryptionCandidates', () => {
+  it('returns empty array for invalid CMS data', () => {
+    const garbage = new Uint8Array([0, 1, 2, 3]).buffer;
+    const result = findDecryptionCandidates(garbage, [encKeyRecord]);
+    expect(result).toEqual([]);
+  });
+});
+
+describe('smimeVerify edge cases', () => {
+  it('throws on invalid ASN.1 data', async () => {
+    const garbage = new Uint8Array([0, 1, 2, 3]).buffer;
+    await expect(smimeVerify(garbage)).rejects.toThrow();
+  });
+});
+
+describe('normalizeCmsBytes', () => {
+  // Helper: a minimal DER-encoded ASN.1 SEQUENCE (0x30 tag)
+  const derBytes = new Uint8Array([0x30, 0x03, 0x02, 0x01, 0x05]);
+
+  it('passes through raw DER unchanged', () => {
+    const result = new Uint8Array(normalizeCmsBytes(derBytes.buffer as ArrayBuffer));
+    expect(result).toEqual(derBytes);
+  });
+
+  it('passes through empty buffer unchanged', () => {
+    const result = normalizeCmsBytes(new ArrayBuffer(0));
+    expect(result.byteLength).toBe(0);
+  });
+
+  it('decodes plain base64 content', () => {
+    const b64 = btoa(String.fromCharCode(...derBytes));
+    const input = new TextEncoder().encode(b64).buffer as ArrayBuffer;
+    const result = new Uint8Array(normalizeCmsBytes(input));
+    expect(result).toEqual(derBytes);
+  });
+
+  it('decodes base64 content with MIME headers', () => {
+    const b64 = btoa(String.fromCharCode(...derBytes));
+    const mime =
+      'Content-Type: application/pkcs7-mime\r\n' +
+      'Content-Transfer-Encoding: base64\r\n' +
+      '\r\n' +
+      b64 + '\r\n';
+    const input = new TextEncoder().encode(mime).buffer as ArrayBuffer;
+    const result = new Uint8Array(normalizeCmsBytes(input));
+    expect(result).toEqual(derBytes);
+  });
+
+  it('decodes PEM-wrapped content', () => {
+    const b64 = btoa(String.fromCharCode(...derBytes));
+    const pem = '-----BEGIN PKCS7-----\n' + b64 + '\n-----END PKCS7-----\n';
+    const input = new TextEncoder().encode(pem).buffer as ArrayBuffer;
+    const result = new Uint8Array(normalizeCmsBytes(input));
+    expect(result).toEqual(derBytes);
+  });
+
+  it('decodes MIME headers with unix line endings', () => {
+    const b64 = btoa(String.fromCharCode(...derBytes));
+    const mime =
+      'Content-Type: application/pkcs7-mime\n' +
+      'Content-Transfer-Encoding: base64\n' +
+      '\n' +
+      b64 + '\n';
+    const input = new TextEncoder().encode(mime).buffer as ArrayBuffer;
+    const result = new Uint8Array(normalizeCmsBytes(input));
+    expect(result).toEqual(derBytes);
+  });
+
+  it('decodes base64 when MIME headers are very long', () => {
+    const b64 = btoa(String.fromCharCode(...derBytes));
+    const longHeader = 'X-Long-Header: ' + 'A'.repeat(3000) + '\r\n';
+    const mime =
+      longHeader +
+      'Content-Type: application/pkcs7-mime\r\n' +
+      'Content-Transfer-Encoding: base64\r\n' +
+      '\r\n' +
+      b64 + '\r\n';
+    const input = new TextEncoder().encode(mime).buffer as ArrayBuffer;
+    const result = new Uint8Array(normalizeCmsBytes(input));
+    expect(result).toEqual(derBytes);
+  });
+
+  it('extracts largest base64 block from multipart-like text', () => {
+    const b64 = btoa(String.fromCharCode(...derBytes));
+    const multipartLike =
+      'Content-Type: multipart/mixed; boundary="b"\r\n\r\n' +
+      '--b\r\n' +
+      'Content-Type: text/plain\r\n\r\n' +
+      'hello\r\n' +
+      '--b\r\n' +
+      'Content-Type: application/pkcs7-mime\r\n' +
+      'Content-Transfer-Encoding: base64\r\n\r\n' +
+      b64 + '\r\n' +
+      '--b--\r\n';
+    const input = new TextEncoder().encode(multipartLike).buffer as ArrayBuffer;
+    const result = new Uint8Array(normalizeCmsBytes(input));
+    expect(result).toEqual(derBytes);
+  });
+
+  it('returns original when content is not decodable', () => {
+    const garbage = new Uint8Array([0x01, 0x02, 0xFF, 0xFE]);
+    const result = normalizeCmsBytes(garbage.buffer as ArrayBuffer);
+    // Should return original since it can\'t be decoded
+    expect(result.byteLength).toBeGreaterThan(0);
+  });
+});

lib/smime/__tests__/smime-detect.test.ts

@@ -0,0 +1,193 @@
+import { describe, it, expect } from 'vitest';
+import { detectSmime } from '../smime-detect';
+
+describe('detectSmime', () => {
+  describe('no S/MIME content', () => {
+    it('returns null type when no arguments provided', () => {
+      const result = detectSmime();
+      expect(result.type).toBeNull();
+      expect(result.supported).toBe(false);
+    });
+
+    it('returns null type for plain text content', () => {
+      const result = detectSmime('text/plain');
+      expect(result.type).toBeNull();
+      expect(result.supported).toBe(false);
+    });
+
+    it('returns null type for multipart/mixed without S/MIME', () => {
+      const result = detectSmime('multipart/mixed; boundary="abc"');
+      expect(result.type).toBeNull();
+      expect(result.supported).toBe(false);
+    });
+  });
+
+  describe('Content-Type header detection', () => {
+    it('detects enveloped-data from Content-Type', () => {
+      const ct = 'application/pkcs7-mime; smime-type=enveloped-data; name="smime.p7m"';
+      const body = { partId: '1', blobId: 'blob1', type: ct };
+      const result = detectSmime(ct, body);
+      expect(result.type).toBe('enveloped-data');
+      expect(result.supported).toBe(true);
+      expect(result.blobId).toBe('blob1');
+      expect(result.partId).toBe('1');
+    });
+
+    it('detects signed-data from Content-Type', () => {
+      const ct = 'application/pkcs7-mime; smime-type=signed-data; name="smime.p7m"';
+      const body = { partId: '2', blobId: 'blob2', type: ct };
+      const result = detectSmime(ct, body);
+      expect(result.type).toBe('signed-data');
+      expect(result.supported).toBe(true);
+      expect(result.blobId).toBe('blob2');
+    });
+
+    it('detects x-pkcs7-mime variant', () => {
+      const ct = 'application/x-pkcs7-mime; smime-type=enveloped-data';
+      const body = { partId: '1', blobId: 'blob1', type: ct };
+      const result = detectSmime(ct, body);
+      expect(result.type).toBe('enveloped-data');
+      expect(result.supported).toBe(true);
+    });
+
+    it('detects detached signature via multipart/signed', () => {
+      const ct = 'multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256';
+      const result = detectSmime(ct);
+      expect(result.type).toBe('detached-sig');
+      expect(result.supported).toBe(false);
+    });
+
+    it('handles generic pkcs7-mime without smime-type', () => {
+      const ct = 'application/pkcs7-mime; name="smime.p7m"';
+      const body = { partId: '1', blobId: 'blob1', type: ct };
+      const result = detectSmime(ct, body);
+      // Should default to enveloped-data for generic pkcs7-mime
+      expect(result.type).toBe('enveloped-data');
+      expect(result.blobId).toBe('blob1');
+    });
+
+    it('is case-insensitive for Content-Type', () => {
+      const ct = 'Application/PKCS7-MIME; smime-type=Enveloped-Data';
+      const body = { partId: '1', blobId: 'b1', type: ct };
+      const result = detectSmime(ct, body);
+      expect(result.type).toBe('enveloped-data');
+      expect(result.supported).toBe(true);
+    });
+  });
+
+  describe('bodyStructure detection', () => {
+    it('finds pkcs7-mime part in bodyStructure tree', () => {
+      const body = {
+        type: 'multipart/mixed',
+        subParts: [
+          { partId: '1', type: 'text/plain', blobId: 'text-blob' },
+          {
+            partId: '2',
+            type: 'application/pkcs7-mime; smime-type=enveloped-data',
+            blobId: 'cms-blob',
+          },
+        ],
+      };
+      const result = detectSmime(undefined, body);
+      expect(result.type).toBe('enveloped-data');
+      expect(result.supported).toBe(true);
+      expect(result.blobId).toBe('cms-blob');
+      expect(result.partId).toBe('2');
+    });
+
+    it('detects detached sig in multipart/signed bodyStructure', () => {
+      const body = {
+        type: 'multipart/signed',
+        subParts: [
+          { partId: '1', type: 'text/plain', blobId: 'text-blob' },
+          { partId: '2', type: 'application/pkcs7-signature', blobId: 'sig-blob' },
+        ],
+      };
+      const result = detectSmime(undefined, body);
+      expect(result.type).toBe('detached-sig');
+      expect(result.supported).toBe(false);
+    });
+
+    it('walks nested bodyStructure', () => {
+      const body = {
+        type: 'multipart/mixed',
+        subParts: [
+          {
+            type: 'multipart/alternative',
+            subParts: [
+              { partId: '1.1', type: 'text/plain', blobId: 'txt' },
+              { partId: '1.2', type: 'text/html', blobId: 'html' },
+            ],
+          },
+          {
+            partId: '2',
+            type: 'application/pkcs7-mime; smime-type=signed-data',
+            blobId: 'sig-blob',
+          },
+        ],
+      };
+      const result = detectSmime(undefined, body);
+      expect(result.type).toBe('signed-data');
+      expect(result.supported).toBe(true);
+      expect(result.blobId).toBe('sig-blob');
+    });
+  });
+
+  describe('attachment detection', () => {
+    it('detects .p7m attachment', () => {
+      const attachments = [
+        { partId: '3', blobId: 'att-blob', name: 'message.p7m', type: 'application/octet-stream' },
+      ];
+      const result = detectSmime(undefined, null, attachments);
+      expect(result.type).toBe('enveloped-data');
+      expect(result.supported).toBe(true);
+      expect(result.blobId).toBe('att-blob');
+    });
+
+    it('detects .p7s attachment as detached-sig', () => {
+      const attachments = [
+        { partId: '3', blobId: 'sig-blob', name: 'smime.p7s', type: 'application/octet-stream' },
+      ];
+      const result = detectSmime(undefined, null, attachments);
+      expect(result.type).toBe('detached-sig');
+      expect(result.supported).toBe(false);
+    });
+
+    it('detects pkcs7-mime attachment type', () => {
+      const attachments = [
+        {
+          partId: '2',
+          blobId: 'enc-blob',
+          name: 'encrypted.bin',
+          type: 'application/pkcs7-mime; smime-type=enveloped-data',
+        },
+      ];
+      const result = detectSmime(undefined, null, attachments);
+      expect(result.type).toBe('enveloped-data');
+      expect(result.supported).toBe(true);
+    });
+
+    it('skips non-S/MIME attachments', () => {
+      const attachments = [
+        { partId: '2', blobId: 'pdf-blob', name: 'document.pdf', type: 'application/pdf' },
+      ];
+      const result = detectSmime(undefined, null, attachments);
+      expect(result.type).toBeNull();
+      expect(result.supported).toBe(false);
+    });
+  });
+
+  describe('priority order', () => {
+    it('Content-Type takes precedence over bodyStructure', () => {
+      const ct = 'application/pkcs7-mime; smime-type=enveloped-data';
+      const body = {
+        partId: '1',
+        blobId: 'from-ct',
+        type: ct,
+      };
+      const result = detectSmime(ct, body);
+      expect(result.type).toBe('enveloped-data');
+      expect(result.blobId).toBe('from-ct');
+    });
+  });
+});

lib/smime/__tests__/smime-store.test.ts

@@ -0,0 +1,394 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+// Mock IndexedDB storage functions before importing store
+vi.mock('@/lib/smime/key-storage', () => ({
+  saveKeyRecord: vi.fn().mockResolvedValue(undefined),
+  listKeyRecords: vi.fn().mockResolvedValue([]),
+  deleteKeyRecord: vi.fn().mockResolvedValue(undefined),
+  savePublicCert: vi.fn().mockResolvedValue(undefined),
+  listPublicCerts: vi.fn().mockResolvedValue([]),
+  deletePublicCert: vi.fn().mockResolvedValue(undefined),
+}));
+
+vi.mock('@/lib/smime/pkcs12-import', () => ({
+  importPkcs12: vi.fn(),
+  unlockPrivateKey: vi.fn(),
+}));
+
+vi.mock('@/lib/smime/certificate-utils', () => ({
+  parseCertificatePemOrDer: vi.fn(),
+  extractCertificateInfo: vi.fn(),
+}));
+
+import { useSmimeStore } from '@/stores/smime-store';
+import { listKeyRecords, listPublicCerts, saveKeyRecord, deleteKeyRecord, savePublicCert, deletePublicCert } from '@/lib/smime/key-storage';
+import { importPkcs12, unlockPrivateKey } from '@/lib/smime/pkcs12-import';
+import type { SmimeKeyRecord, SmimePublicCert } from '@/lib/smime/types';
+
+const mockKeyRecord: SmimeKeyRecord = {
+  id: 'key-1',
+  email: 'user@example.com',
+  certificate: new ArrayBuffer(10),
+  certificateChain: [],
+  encryptedPrivateKey: new ArrayBuffer(32),
+  salt: new ArrayBuffer(16),
+  iv: new ArrayBuffer(12),
+  kdfIterations: 600000,
+  issuer: 'CN=Test CA',
+  subject: 'CN=Test User',
+  serialNumber: '01',
+  notBefore: '2024-01-01T00:00:00Z',
+  notAfter: '2030-12-31T23:59:59Z',
+  fingerprint: 'aa:bb:cc',
+  algorithm: 'RSA-2048',
+  capabilities: { canSign: true, canEncrypt: true },
+};
+
+beforeEach(() => {
+  localStorage.clear();
+  sessionStorage.clear();
+  // Reset store state
+  useSmimeStore.setState({
+    keyRecords: [],
+    publicCerts: [],
+    unlockedKeys: new Map(),
+    unlockedDecryptionKeys: new Map(),
+    identityKeyBindings: {},
+    defaultSignIdentity: {},
+    defaultEncrypt: false,
+    rememberUnlockedKeys: false,
+    autoImportSignerCerts: false,
+    isLoading: false,
+    error: null,
+  });
+  vi.clearAllMocks();
+});
+
+describe('smime-store', () => {
+  describe('load', () => {
+    it('loads key records and public certs from IndexedDB', async () => {
+      const records = [mockKeyRecord];
+      const certs: SmimePublicCert[] = [];
+      vi.mocked(listKeyRecords).mockResolvedValue(records);
+      vi.mocked(listPublicCerts).mockResolvedValue(certs);
+
+      await useSmimeStore.getState().load();
+
+      const state = useSmimeStore.getState();
+      expect(state.keyRecords).toEqual(records);
+      expect(state.publicCerts).toEqual(certs);
+      expect(state.isLoading).toBe(false);
+    });
+
+    it('re-unlocks remembered keys during load', async () => {
+      const records = [mockKeyRecord];
+      const mockSigningKey = {} as CryptoKey;
+      const mockDecryptionKey = {} as CryptoKey;
+      sessionStorage.setItem('smime-unlocked-session', JSON.stringify({ 'key-1': 'passphrase' }));
+      useSmimeStore.setState({ rememberUnlockedKeys: true });
+      vi.mocked(listKeyRecords).mockResolvedValue(records);
+      vi.mocked(listPublicCerts).mockResolvedValue([]);
+      vi.mocked(unlockPrivateKey).mockResolvedValue({
+        signingKey: mockSigningKey,
+        decryptionKey: mockDecryptionKey,
+      });
+
+      await useSmimeStore.getState().load();
+
+      expect(unlockPrivateKey).toHaveBeenCalledWith(mockKeyRecord, 'passphrase');
+      expect(useSmimeStore.getState().getUnlockedKey('key-1')).toBe(mockSigningKey);
+      expect(useSmimeStore.getState().unlockedDecryptionKeys.get('key-1')).toBe(mockDecryptionKey);
+    });
+
+    it('removes stale remembered keys when re-unlock fails', async () => {
+      const records = [mockKeyRecord];
+      sessionStorage.setItem('smime-unlocked-session', JSON.stringify({ 'key-1': 'bad-pass' }));
+      useSmimeStore.setState({ rememberUnlockedKeys: true });
+      vi.mocked(listKeyRecords).mockResolvedValue(records);
+      vi.mocked(listPublicCerts).mockResolvedValue([]);
+      vi.mocked(unlockPrivateKey).mockRejectedValue(new Error('Incorrect passphrase'));
+
+      await useSmimeStore.getState().load();
+
+      expect(sessionStorage.getItem('smime-unlocked-session')).toBeNull();
+      expect(useSmimeStore.getState().isKeyUnlocked('key-1')).toBe(false);
+    });
+
+    it('sets error on failure', async () => {
+      vi.mocked(listKeyRecords).mockRejectedValue(new Error('DB failed'));
+
+      await useSmimeStore.getState().load();
+
+      expect(useSmimeStore.getState().error).toBe('DB failed');
+      expect(useSmimeStore.getState().isLoading).toBe(false);
+    });
+  });
+
+  describe('importPKCS12', () => {
+    it('imports and adds key record', async () => {
+      vi.mocked(importPkcs12).mockResolvedValue({
+        keyRecord: mockKeyRecord,
+        certInfo: {} as any,
+      });
+
+      const result = await useSmimeStore.getState().importPKCS12(
+        new ArrayBuffer(10),
+        'p12pass',
+        'storagepass',
+      );
+
+      expect(result.id).toBe('key-1');
+      expect(saveKeyRecord).toHaveBeenCalledWith(mockKeyRecord);
+      expect(useSmimeStore.getState().keyRecords).toHaveLength(1);
+    });
+
+    it('sets error on import failure', async () => {
+      vi.mocked(importPkcs12).mockRejectedValue(new Error('Bad password'));
+
+      await expect(
+        useSmimeStore.getState().importPKCS12(new ArrayBuffer(10), 'wrong', 'pass'),
+      ).rejects.toThrow('Bad password');
+
+      expect(useSmimeStore.getState().error).toBe('Bad password');
+    });
+  });
+
+  describe('removeKeyRecord', () => {
+    it('removes key record and clears bindings', async () => {
+      useSmimeStore.setState({
+        keyRecords: [mockKeyRecord],
+        identityKeyBindings: { 'identity-1': 'key-1' },
+        unlockedKeys: new Map([['key-1', {} as CryptoKey]]),
+        unlockedDecryptionKeys: new Map([['key-1', {} as CryptoKey]]),
+      });
+
+      await useSmimeStore.getState().removeKeyRecord('key-1');
+
+      expect(deleteKeyRecord).toHaveBeenCalledWith('key-1');
+      expect(useSmimeStore.getState().keyRecords).toHaveLength(0);
+      expect(useSmimeStore.getState().identityKeyBindings).toEqual({});
+      expect(useSmimeStore.getState().unlockedKeys.has('key-1')).toBe(false);
+      expect(useSmimeStore.getState().unlockedDecryptionKeys.has('key-1')).toBe(false);
+    });
+  });
+
+  describe('removePublicCert', () => {
+    it('removes public cert', async () => {
+      const cert: SmimePublicCert = {
+        id: 'cert-1',
+        email: 'recipient@example.com',
+        certificate: new ArrayBuffer(10),
+        issuer: 'CN=CA',
+        subject: 'CN=Recipient',
+        notBefore: '2024-01-01T00:00:00Z',
+        notAfter: '2030-12-31T23:59:59Z',
+        fingerprint: 'aa:bb',
+        source: 'manual',
+      };
+      useSmimeStore.setState({ publicCerts: [cert] });
+
+      await useSmimeStore.getState().removePublicCert('cert-1');
+
+      expect(deletePublicCert).toHaveBeenCalledWith('cert-1');
+      expect(useSmimeStore.getState().publicCerts).toHaveLength(0);
+    });
+  });
+
+  describe('unlockKey + lockKey', () => {
+    it('unlocks a key', async () => {
+      const mockSigningKey = {} as CryptoKey;
+      const mockDecryptionKey = {} as CryptoKey;
+      vi.mocked(unlockPrivateKey).mockResolvedValue({ signingKey: mockSigningKey, decryptionKey: mockDecryptionKey });
+      useSmimeStore.setState({ keyRecords: [mockKeyRecord] });
+
+      await useSmimeStore.getState().unlockKey('key-1', 'passphrase');
+
+      expect(useSmimeStore.getState().isKeyUnlocked('key-1')).toBe(true);
+      expect(useSmimeStore.getState().getUnlockedKey('key-1')).toBe(mockSigningKey);
+      expect(useSmimeStore.getState().unlockedDecryptionKeys.get('key-1')).toBe(mockDecryptionKey);
+    });
+
+    it('stores the passphrase for session rehydration when remember is enabled', async () => {
+      const mockSigningKey = {} as CryptoKey;
+      vi.mocked(unlockPrivateKey).mockResolvedValue({ signingKey: mockSigningKey });
+      useSmimeStore.setState({ keyRecords: [mockKeyRecord], rememberUnlockedKeys: true });
+
+      await useSmimeStore.getState().unlockKey('key-1', 'passphrase');
+
+      expect(sessionStorage.getItem('smime-unlocked-session')).toBe(
+        JSON.stringify({ 'key-1': 'passphrase' }),
+      );
+    });
+
+    it('stores only the signing key when no decryption key is available', async () => {
+      const mockSigningKey = {} as CryptoKey;
+      vi.mocked(unlockPrivateKey).mockResolvedValue({ signingKey: mockSigningKey });
+      useSmimeStore.setState({ keyRecords: [mockKeyRecord] });
+
+      await useSmimeStore.getState().unlockKey('key-1', 'passphrase');
+
+      expect(useSmimeStore.getState().getUnlockedKey('key-1')).toBe(mockSigningKey);
+      expect(useSmimeStore.getState().unlockedDecryptionKeys.has('key-1')).toBe(false);
+    });
+
+    it('throws for non-existent key record', async () => {
+      await expect(
+        useSmimeStore.getState().unlockKey('non-existent', 'pass'),
+      ).rejects.toThrow('Key record not found');
+    });
+
+    it('locks a key', () => {
+      sessionStorage.setItem('smime-unlocked-session', JSON.stringify({ 'key-1': 'passphrase' }));
+      useSmimeStore.setState({
+        unlockedKeys: new Map([['key-1', {} as CryptoKey]]),
+        unlockedDecryptionKeys: new Map([['key-1', {} as CryptoKey]]),
+      });
+
+      useSmimeStore.getState().lockKey('key-1');
+
+      expect(useSmimeStore.getState().isKeyUnlocked('key-1')).toBe(false);
+      expect(useSmimeStore.getState().unlockedDecryptionKeys.has('key-1')).toBe(false);
+      expect(sessionStorage.getItem('smime-unlocked-session')).toBeNull();
+    });
+
+    it('locks all keys', () => {
+      sessionStorage.setItem(
+        'smime-unlocked-session',
+        JSON.stringify({ 'key-1': 'one', 'key-2': 'two' }),
+      );
+      useSmimeStore.setState({
+        unlockedKeys: new Map([
+          ['key-1', {} as CryptoKey],
+          ['key-2', {} as CryptoKey],
+        ]),
+        unlockedDecryptionKeys: new Map([
+          ['key-1', {} as CryptoKey],
+          ['key-2', {} as CryptoKey],
+        ]),
+      });
+
+      useSmimeStore.getState().lockAllKeys();
+
+      expect(useSmimeStore.getState().unlockedKeys.size).toBe(0);
+      expect(useSmimeStore.getState().unlockedDecryptionKeys.size).toBe(0);
+      expect(sessionStorage.getItem('smime-unlocked-session')).toBeNull();
+    });
+  });
+
+  describe('identity bindings', () => {
+    it('binds an identity to a key', () => {
+      useSmimeStore.getState().bindIdentityToKey('identity-1', 'key-1');
+      expect(useSmimeStore.getState().identityKeyBindings['identity-1']).toBe('key-1');
+    });
+
+    it('unbinds an identity', () => {
+      useSmimeStore.setState({ identityKeyBindings: { 'identity-1': 'key-1' } });
+      useSmimeStore.getState().bindIdentityToKey('identity-1', null);
+      expect(useSmimeStore.getState().identityKeyBindings['identity-1']).toBeUndefined();
+    });
+
+    it('getKeyRecordForIdentity returns the bound record', () => {
+      useSmimeStore.setState({
+        keyRecords: [mockKeyRecord],
+        identityKeyBindings: { 'identity-1': 'key-1' },
+      });
+
+      const record = useSmimeStore.getState().getKeyRecordForIdentity('identity-1');
+      expect(record?.id).toBe('key-1');
+    });
+
+    it('getKeyRecordForIdentity returns undefined for unbound identity', () => {
+      const record = useSmimeStore.getState().getKeyRecordForIdentity('identity-2');
+      expect(record).toBeUndefined();
+    });
+  });
+
+  describe('getPublicCertForEmail', () => {
+    it('finds cert by email (case-insensitive)', () => {
+      const cert: SmimePublicCert = {
+        id: 'c1',
+        email: 'bob@example.com',
+        certificate: new ArrayBuffer(10),
+        issuer: 'CN=CA',
+        subject: 'CN=Bob',
+        notBefore: '2024-01-01',
+        notAfter: '2030-12-31',
+        fingerprint: 'ff',
+        source: 'manual',
+      };
+      useSmimeStore.setState({ publicCerts: [cert] });
+
+      expect(useSmimeStore.getState().getPublicCertForEmail('Bob@Example.COM')?.id).toBe('c1');
+    });
+
+    it('returns undefined when not found', () => {
+      expect(useSmimeStore.getState().getPublicCertForEmail('nobody@test.com')).toBeUndefined();
+    });
+  });
+
+  describe('getRecipientCerts', () => {
+    it('partitions emails into found and missing', () => {
+      const cert: SmimePublicCert = {
+        id: 'c1',
+        email: 'known@example.com',
+        certificate: new ArrayBuffer(10),
+        issuer: '',
+        subject: '',
+        notBefore: '',
+        notAfter: '',
+        fingerprint: '',
+        source: 'manual',
+      };
+      useSmimeStore.setState({ publicCerts: [cert] });
+
+      const { found, missing } = useSmimeStore.getState().getRecipientCerts([
+        'known@example.com',
+        'unknown@example.com',
+      ]);
+
+      expect(found).toHaveLength(1);
+      expect(found[0].id).toBe('c1');
+      expect(missing).toEqual(['unknown@example.com']);
+    });
+  });
+
+  describe('preferences', () => {
+    it('sets sign default for identity', () => {
+      useSmimeStore.getState().setSignDefault('identity-1', true);
+      expect(useSmimeStore.getState().defaultSignIdentity['identity-1']).toBe(true);
+    });
+
+    it('sets encrypt default', () => {
+      useSmimeStore.getState().setEncryptDefault(true);
+      expect(useSmimeStore.getState().defaultEncrypt).toBe(true);
+    });
+
+    it('sets remember unlocked keys and clears when disabled', () => {
+      sessionStorage.setItem('smime-unlocked-session', JSON.stringify({ 'key-1': 'passphrase' }));
+      useSmimeStore.setState({
+        unlockedKeys: new Map([['key-1', {} as CryptoKey]]),
+      });
+
+      useSmimeStore.getState().setRememberUnlockedKeys(false);
+
+      expect(useSmimeStore.getState().rememberUnlockedKeys).toBe(false);
+      expect(useSmimeStore.getState().unlockedKeys.size).toBe(0);
+      expect(sessionStorage.getItem('smime-unlocked-session')).toBeNull();
+    });
+
+    it('sets auto import signer certs', () => {
+      useSmimeStore.getState().setAutoImportSignerCerts(true);
+      expect(useSmimeStore.getState().autoImportSignerCerts).toBe(true);
+    });
+  });
+
+  describe('setError', () => {
+    it('sets and clears error', () => {
+      useSmimeStore.getState().setError('Something went wrong');
+      expect(useSmimeStore.getState().error).toBe('Something went wrong');
+
+      useSmimeStore.getState().setError(null);
+      expect(useSmimeStore.getState().error).toBeNull();
+    });
+  });
+});

lib/smime/certificate-utils.ts

@@ -0,0 +1,243 @@
+import * as asn1js from 'asn1js';
+import * as pkijs from 'pkijs';
+import { Convert } from 'pvtsutils';
+import type { CertificateInfo, SmimeKeyCapabilities } from './types';
+
+/** OID for id-kp-emailProtection (S/MIME) */
+const OID_EMAIL_PROTECTION = '1.3.6.1.5.5.7.3.4';
+
+/** OID for SubjectAlternativeName */
+const OID_SAN = '2.5.29.17';
+
+// ── PEM/DER conversions ──────────────────────────────────────────────
+
+export function pemToDer(pem: string): ArrayBuffer {
+  const lines = pem
+    .replace(/-----BEGIN [^-]+-----/, '')
+    .replace(/-----END [^-]+-----/, '')
+    .replace(/\s/g, '');
+  return Convert.FromBase64(lines);
+}
+
+export function derToPem(der: ArrayBuffer, label: string): string {
+  const b64 = Convert.ToBase64(der);
+  const lines: string[] = [];
+  for (let i = 0; i < b64.length; i += 64) {
+    lines.push(b64.slice(i, i + 64));
+  }
+  return `-----BEGIN ${label}-----\n${lines.join('\n')}\n-----END ${label}-----`;
+}
+
+export function isPem(data: string): boolean {
+  return /-----BEGIN (CERTIFICATE|PKCS12|ENCRYPTED PRIVATE KEY|PRIVATE KEY)-----/.test(data);
+}
+
+// ── Certificate parsing ──────────────────────────────────────────────
+
+export function parseCertificateDer(der: ArrayBuffer): pkijs.Certificate {
+  const asn1 = asn1js.fromBER(der);
+  if (asn1.offset === -1) {
+    throw new Error('Invalid DER data: ASN.1 parsing failed');
+  }
+  return new pkijs.Certificate({ schema: asn1.result });
+}
+
+export function parseCertificatePemOrDer(data: ArrayBuffer | string): pkijs.Certificate {
+  if (typeof data === 'string') {
+    if (isPem(data)) {
+      return parseCertificateDer(pemToDer(data));
+    }
+    throw new Error('String input is not PEM-encoded');
+  }
+  // ArrayBuffer might contain PEM text rather than DER binary
+  // PEM files start with "-----BEGIN " (0x2D 0x2D 0x2D 0x2D 0x2D 0x42)
+  const header = new Uint8Array(data, 0, Math.min(20, data.byteLength));
+  const maybePem = String.fromCharCode(...header);
+  if (maybePem.startsWith('-----BEGIN ')) {
+    const text = new TextDecoder().decode(data);
+    return parseCertificateDer(pemToDer(text));
+  }
+  return parseCertificateDer(data);
+}
+
+// ── Metadata extraction ──────────────────────────────────────────────
+
+function rdnToString(rdn: pkijs.RelativeDistinguishedNames): string {
+  return rdn.typesAndValues
+    .map((tv) => {
+      const oid = tv.type;
+      const val = tv.value.valueBlock.value;
+      const name = oidToName(oid);
+      return `${name}=${val}`;
+    })
+    .join(', ');
+}
+
+function oidToName(oid: string): string {
+  const map: Record<string, string> = {
+    '2.5.4.3': 'CN',
+    '2.5.4.6': 'C',
+    '2.5.4.7': 'L',
+    '2.5.4.8': 'ST',
+    '2.5.4.10': 'O',
+    '2.5.4.11': 'OU',
+    '1.2.840.113549.1.9.1': 'E',
+  };
+  return map[oid] ?? oid;
+}
+
+export async function computeFingerprint(der: ArrayBuffer): Promise<string> {
+  const hash = await crypto.subtle.digest('SHA-256', new Uint8Array(der));
+  return Array.from(new Uint8Array(hash))
+    .map((b) => b.toString(16).padStart(2, '0'))
+    .join(':');
+}
+
+function extractAlgorithm(cert: pkijs.Certificate): string {
+  const algOid = cert.subjectPublicKeyInfo.algorithm.algorithmId;
+  // RSA
+  if (algOid === '1.2.840.113549.1.1.1') {
+    const pubKey = cert.subjectPublicKeyInfo;
+    try {
+      const asn1Pub = asn1js.fromBER(pubKey.subjectPublicKey.valueBlock.valueHexView);
+      const seq = asn1Pub.result as asn1js.Sequence;
+      const modulus = seq.valueBlock.value[0] as asn1js.Integer;
+      const bitLen = (modulus.valueBlock.valueHexView.byteLength - 1) * 8;
+      return `RSA-${bitLen}`;
+    } catch {
+      return 'RSA';
+    }
+  }
+  // ECDSA
+  if (algOid === '1.2.840.10045.2.1') {
+    const params = cert.subjectPublicKeyInfo.algorithm.algorithmParams;
+    if (params instanceof asn1js.ObjectIdentifier) {
+      const curveOid = params.valueBlock.toString();
+      const curves: Record<string, string> = {
+        '1.2.840.10045.3.1.7': 'ECDSA-P256',
+        '1.3.132.0.34': 'ECDSA-P384',
+        '1.3.132.0.35': 'ECDSA-P521',
+      };
+      return curves[curveOid] ?? 'ECDSA';
+    }
+    return 'ECDSA';
+  }
+  return algOid;
+}
+
+function extractKeyUsage(cert: pkijs.Certificate): string[] | undefined {
+  const ext = cert.extensions?.find((e) => e.extnID === '2.5.29.15');
+  if (!ext?.parsedValue) return undefined;
+  const ku = ext.parsedValue as {
+    digitalSignature?: boolean;
+    contentCommitment?: boolean;
+    keyEncipherment?: boolean;
+    dataEncipherment?: boolean;
+    keyAgreement?: boolean;
+    keyCertSign?: boolean;
+    cRLSign?: boolean;
+    encipherOnly?: boolean;
+    decipherOnly?: boolean;
+  };
+  const names: string[] = [];
+  if (ku.digitalSignature) names.push('digitalSignature');
+  if (ku.contentCommitment) names.push('contentCommitment');
+  if (ku.keyEncipherment) names.push('keyEncipherment');
+  if (ku.dataEncipherment) names.push('dataEncipherment');
+  if (ku.keyAgreement) names.push('keyAgreement');
+  if (ku.keyCertSign) names.push('keyCertSign');
+  if (ku.cRLSign) names.push('cRLSign');
+  if (ku.encipherOnly) names.push('encipherOnly');
+  if (ku.decipherOnly) names.push('decipherOnly');
+  return names;
+}
+
+function extractExtendedKeyUsage(cert: pkijs.Certificate): string[] | undefined {
+  const ext = cert.extensions?.find((e) => e.extnID === '2.5.29.37');
+  if (!ext?.parsedValue) return undefined;
+  const eku = ext.parsedValue as pkijs.ExtKeyUsage;
+  return eku.keyPurposes;
+}
+
+function extractEmailAddresses(cert: pkijs.Certificate): string[] {
+  const emails: string[] = [];
+
+  // From subject emailAddress attribute
+  for (const tv of cert.subject.typesAndValues) {
+    if (tv.type === '1.2.840.113549.1.9.1') {
+      emails.push(tv.value.valueBlock.value as string);
+    }
+  }
+
+  // From SubjectAlternativeName
+  const sanExt = cert.extensions?.find((e) => e.extnID === OID_SAN);
+  if (sanExt?.parsedValue) {
+    const san = sanExt.parsedValue as pkijs.GeneralNames;
+    for (const name of san.names) {
+      // type 1 = rfc822Name
+      if (name.type === 1 && typeof name.value === 'string') {
+        if (!emails.includes(name.value)) {
+          emails.push(name.value);
+        }
+      }
+    }
+  }
+
+  return emails;
+}
+
+/** Determine signing/encryption capabilities from KU / EKU. Tolerant of absent extensions. */
+export function classifyCapabilities(cert: pkijs.Certificate): SmimeKeyCapabilities {
+  const ku = extractKeyUsage(cert);
+  const eku = extractExtendedKeyUsage(cert);
+
+  let canSign = true;
+  let canEncrypt = true;
+
+  // If KeyUsage is present, check explicit bits
+  if (ku) {
+    canSign = ku.includes('digitalSignature') || ku.includes('contentCommitment');
+    canEncrypt = ku.includes('keyEncipherment') || ku.includes('dataEncipherment') || ku.includes('keyAgreement');
+  }
+
+  // If EKU is present, only reject if it explicitly excludes emailProtection
+  if (eku && eku.length > 0) {
+    const hasEmailProtection = eku.includes(OID_EMAIL_PROTECTION);
+    // Only restrict if EKU is present and does NOT include emailProtection
+    if (!hasEmailProtection) {
+      canSign = false;
+      canEncrypt = false;
+    }
+  }
+
+  return { canSign, canEncrypt };
+}
+
+/** Extract full metadata from a parsed certificate. */
+export async function extractCertificateInfo(
+  cert: pkijs.Certificate,
+  der: ArrayBuffer,
+): Promise<CertificateInfo> {
+  const fingerprint = await computeFingerprint(der);
+  const ku = extractKeyUsage(cert);
+  const eku = extractExtendedKeyUsage(cert);
+  const capabilities = classifyCapabilities(cert);
+
+  return {
+    subject: rdnToString(cert.subject),
+    issuer: rdnToString(cert.issuer),
+    serialNumber: cert.serialNumber.valueBlock.valueHexView
+      ? Array.from(new Uint8Array(cert.serialNumber.valueBlock.valueHexView))
+          .map((b) => b.toString(16).padStart(2, '0'))
+          .join(':')
+      : cert.serialNumber.valueBlock.toString(),
+    notBefore: cert.notBefore.value.toISOString(),
+    notAfter: cert.notAfter.value.toISOString(),
+    fingerprint,
+    algorithm: extractAlgorithm(cert),
+    keyUsage: ku,
+    extendedKeyUsage: eku,
+    emailAddresses: extractEmailAddresses(cert),
+    capabilities,
+  };
+}

lib/smime/crypto-engine.ts

@@ -0,0 +1,76 @@
+/**
+ * Crypto engine backed by webcrypto-liner for legacy algorithm support.
+ *
+ * webcrypto-liner extends the native Web Crypto API with algorithms
+ * like DES-EDE3-CBC (3DES) that are commonly found in S/MIME messages
+ * and PKCS#12 files produced by legacy clients (Outlook, Thunderbird, etc.).
+ *
+ * Native Web Crypto calls are passed through to the real implementation;
+ * liner only intercepts algorithms that the browser doesn't natively support.
+ */
+
+import * as pkijs from 'pkijs';
+
+// webcrypto-liner exports a Crypto constructor at runtime that extends native
+// Web Crypto with legacy algorithms (3DES, etc.). Its type declarations only
+// expose the type alias, so we import the module dynamically and cast.
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+const liner = require('webcrypto-liner') as {
+  Crypto: { new (): Crypto };
+  setCrypto: (subtle: SubtleCrypto) => void;
+  nativeCrypto: Crypto | Record<string, never>;
+};
+
+let linerEngine: pkijs.CryptoEngine | null = null;
+let linerCryptoInstance: Crypto | null = null;
+
+function ensureLiner() {
+  if (!linerCryptoInstance) {
+    // In Node.js, webcrypto-liner can't auto-detect the native crypto
+    // (it looks for self.crypto which doesn't exist). Feed it manually
+    // so that native algorithms (RSA, AES, etc.) stay hardware-accelerated
+    // and only truly missing algorithms (3DES) use the software fallback.
+    if (
+      typeof liner.nativeCrypto?.getRandomValues !== 'function' &&
+      typeof globalThis.crypto?.subtle !== 'undefined'
+    ) {
+      liner.setCrypto(globalThis.crypto.subtle);
+    }
+    linerCryptoInstance = new liner.Crypto();
+  }
+  if (!linerEngine) {
+    linerEngine = new pkijs.CryptoEngine({
+      crypto: linerCryptoInstance,
+      subtle: linerCryptoInstance.subtle,
+      name: 'webcrypto-liner',
+    });
+  }
+}
+
+/** Get a PKI.js CryptoEngine with 3DES (and other legacy algorithm) support. */
+export function getLinerCryptoEngine(): pkijs.CryptoEngine {
+  ensureLiner();
+  return linerEngine!;
+}
+
+/**
+ * Run an async operation with the global PKI.js engine set to webcrypto-liner,
+ * then restore the previous engine afterwards.
+ *
+ * Required for operations that use the global engine internally
+ * (e.g. PFX.parseInternalValues for PKCS#12 import).
+ */
+export async function withLinerEngine<T>(fn: () => Promise<T>): Promise<T> {
+  ensureLiner();
+
+  // Save the current global engine so we can restore it
+  const prev = pkijs.getEngine();
+
+  pkijs.setEngine('webcrypto-liner', linerCryptoInstance!, linerEngine!);
+  try {
+    return await fn();
+  } finally {
+    // Restore the previous engine
+    pkijs.setEngine(prev.name, prev.crypto as unknown as pkijs.CryptoEngine);
+  }
+}

lib/smime/key-storage.ts

@@ -0,0 +1,101 @@
+import type { SmimeKeyRecord, SmimePublicCert } from './types';
+
+const DB_NAME = 'smime-store';
+const DB_VERSION = 1;
+const KEY_RECORDS_STORE = 'key-records';
+const PUBLIC_CERTS_STORE = 'public-certs';
+
+function openDB(): Promise<IDBDatabase> {
+  return new Promise((resolve, reject) => {
+    const request = indexedDB.open(DB_NAME, DB_VERSION);
+    request.onupgradeneeded = () => {
+      const db = request.result;
+      if (!db.objectStoreNames.contains(KEY_RECORDS_STORE)) {
+        const keyStore = db.createObjectStore(KEY_RECORDS_STORE, { keyPath: 'id' });
+        keyStore.createIndex('email', 'email', { unique: false });
+      }
+      if (!db.objectStoreNames.contains(PUBLIC_CERTS_STORE)) {
+        const certStore = db.createObjectStore(PUBLIC_CERTS_STORE, { keyPath: 'id' });
+        certStore.createIndex('email', 'email', { unique: false });
+      }
+    };
+    request.onsuccess = () => resolve(request.result);
+    request.onerror = () => reject(request.error);
+  });
+}
+
+function txPromise<T>(
+  db: IDBDatabase,
+  storeName: string,
+  mode: globalThis.IDBTransactionMode,
+  fn: (store: IDBObjectStore) => IDBRequest<T>,
+): Promise<T> {
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction(storeName, mode);
+    const store = tx.objectStore(storeName);
+    const req = fn(store);
+    req.onsuccess = () => resolve(req.result);
+    req.onerror = () => reject(req.error);
+  });
+}
+
+// ── Key record CRUD ─────────────────────────────────────────────────
+
+export async function saveKeyRecord(record: SmimeKeyRecord): Promise<void> {
+  const db = await openDB();
+  await txPromise(db, KEY_RECORDS_STORE, 'readwrite', (s) => s.put(record));
+}
+
+export async function getKeyRecord(id: string): Promise<SmimeKeyRecord | undefined> {
+  const db = await openDB();
+  return txPromise(db, KEY_RECORDS_STORE, 'readonly', (s) => s.get(id));
+}
+
+export async function getKeyRecordForEmail(email: string): Promise<SmimeKeyRecord | undefined> {
+  const db = await openDB();
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction(KEY_RECORDS_STORE, 'readonly');
+    const idx = tx.objectStore(KEY_RECORDS_STORE).index('email');
+    const req = idx.get(email.toLowerCase());
+    req.onsuccess = () => resolve(req.result ?? undefined);
+    req.onerror = () => reject(req.error);
+  });
+}
+
+export async function listKeyRecords(): Promise<SmimeKeyRecord[]> {
+  const db = await openDB();
+  return txPromise(db, KEY_RECORDS_STORE, 'readonly', (s) => s.getAll());
+}
+
+export async function deleteKeyRecord(id: string): Promise<void> {
+  const db = await openDB();
+  await txPromise(db, KEY_RECORDS_STORE, 'readwrite', (s) => s.delete(id));
+}
+
+// ── Public cert CRUD ────────────────────────────────────────────────
+
+export async function savePublicCert(cert: SmimePublicCert): Promise<void> {
+  const db = await openDB();
+  await txPromise(db, PUBLIC_CERTS_STORE, 'readwrite', (s) => s.put(cert));
+}
+
+export async function getPublicCertForEmail(email: string): Promise<SmimePublicCert | undefined> {
+  const db = await openDB();
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction(PUBLIC_CERTS_STORE, 'readonly');
+    const idx = tx.objectStore(PUBLIC_CERTS_STORE).index('email');
+    const req = idx.get(email.toLowerCase());
+    req.onsuccess = () => resolve(req.result ?? undefined);
+    req.onerror = () => reject(req.error);
+  });
+}
+
+export async function listPublicCerts(): Promise<SmimePublicCert[]> {
+  const db = await openDB();
+  return txPromise(db, PUBLIC_CERTS_STORE, 'readonly', (s) => s.getAll());
+}
+
+export async function deletePublicCert(id: string): Promise<void> {
+  const db = await openDB();
+  await txPromise(db, PUBLIC_CERTS_STORE, 'readwrite', (s) => s.delete(id));
+}

lib/smime/mime-builder.ts

@@ -0,0 +1,337 @@
+/**
+ * Minimal, deterministic MIME builder for outgoing S/MIME messages.
+ *
+ * Produces canonical text suitable for CMS signing/encryption.
+ * All line endings are CRLF per RFC 5322.
+ */
+
+const CRLF = '\r\n';
+
+export interface MimeAttachment {
+  filename: string;
+  contentType: string;
+  content: ArrayBuffer;
+  cid?: string; // for inline images
+}
+
+export interface MimeMessageInput {
+  from: { name?: string; email: string };
+  to: { name?: string; email: string }[];
+  cc?: { name?: string; email: string }[];
+  bcc?: { name?: string; email: string }[];
+  subject: string;
+  date?: Date;
+  messageId?: string;
+  inReplyTo?: string;
+  references?: string[];
+  textBody?: string;
+  htmlBody?: string;
+  attachments?: MimeAttachment[];
+}
+
+/** Build a complete MIME message and return it as a Uint8Array (UTF-8). */
+export function buildMimeMessage(input: MimeMessageInput): Uint8Array {
+  const boundary = generateBoundary();
+  const lines: string[] = [];
+
+  // Headers
+  lines.push(formatHeader('From', formatAddress(input.from)));
+  lines.push(formatHeader('To', input.to.map(formatAddress).join(', ')));
+  if (input.cc?.length) {
+    lines.push(formatHeader('Cc', input.cc.map(formatAddress).join(', ')));
+  }
+  // BCC is intentionally omitted from the MIME headers per RFC 5322
+  lines.push(formatHeader('Subject', encodeHeaderValue(input.subject)));
+  lines.push(formatHeader('Date', formatDate(input.date ?? new Date())));
+  lines.push(formatHeader('Message-ID', input.messageId ?? `<${crypto.randomUUID()}@smime.local>`));
+  if (input.inReplyTo) {
+    lines.push(formatHeader('In-Reply-To', input.inReplyTo));
+  }
+  if (input.references?.length) {
+    lines.push(formatHeader('References', input.references.join(' ')));
+  }
+  lines.push('MIME-Version: 1.0');
+
+  const hasText = !!input.textBody;
+  const hasHtml = !!input.htmlBody;
+  const hasAttachments = !!input.attachments?.length;
+
+  if (!hasAttachments && hasText && !hasHtml) {
+    // text/plain only
+    lines.push('Content-Type: text/plain; charset=utf-8');
+    lines.push('Content-Transfer-Encoding: quoted-printable');
+    lines.push('');
+    lines.push(quotedPrintableEncode(input.textBody!));
+  } else if (!hasAttachments && hasText && hasHtml) {
+    // multipart/alternative
+    const altBoundary = generateBoundary();
+    lines.push(`Content-Type: multipart/alternative; boundary="${altBoundary}"`);
+    lines.push('');
+    lines.push(`--${altBoundary}`);
+    lines.push('Content-Type: text/plain; charset=utf-8');
+    lines.push('Content-Transfer-Encoding: quoted-printable');
+    lines.push('');
+    lines.push(quotedPrintableEncode(input.textBody!));
+    lines.push(`--${altBoundary}`);
+    lines.push('Content-Type: text/html; charset=utf-8');
+    lines.push('Content-Transfer-Encoding: quoted-printable');
+    lines.push('');
+    lines.push(quotedPrintableEncode(input.htmlBody!));
+    lines.push(`--${altBoundary}--`);
+  } else if (!hasAttachments && !hasText && hasHtml) {
+    // html only
+    lines.push('Content-Type: text/html; charset=utf-8');
+    lines.push('Content-Transfer-Encoding: quoted-printable');
+    lines.push('');
+    lines.push(quotedPrintableEncode(input.htmlBody!));
+  } else if (hasAttachments) {
+    // multipart/mixed
+    lines.push(`Content-Type: multipart/mixed; boundary="${boundary}"`);
+    lines.push('');
+
+    // Body part
+    if (hasText && hasHtml) {
+      const altBoundary = generateBoundary();
+      lines.push(`--${boundary}`);
+      lines.push(`Content-Type: multipart/alternative; boundary="${altBoundary}"`);
+      lines.push('');
+      lines.push(`--${altBoundary}`);
+      lines.push('Content-Type: text/plain; charset=utf-8');
+      lines.push('Content-Transfer-Encoding: quoted-printable');
+      lines.push('');
+      lines.push(quotedPrintableEncode(input.textBody!));
+      lines.push(`--${altBoundary}`);
+      lines.push('Content-Type: text/html; charset=utf-8');
+      lines.push('Content-Transfer-Encoding: quoted-printable');
+      lines.push('');
+      lines.push(quotedPrintableEncode(input.htmlBody!));
+      lines.push(`--${altBoundary}--`);
+    } else if (hasText) {
+      lines.push(`--${boundary}`);
+      lines.push('Content-Type: text/plain; charset=utf-8');
+      lines.push('Content-Transfer-Encoding: quoted-printable');
+      lines.push('');
+      lines.push(quotedPrintableEncode(input.textBody!));
+    } else if (hasHtml) {
+      lines.push(`--${boundary}`);
+      lines.push('Content-Type: text/html; charset=utf-8');
+      lines.push('Content-Transfer-Encoding: quoted-printable');
+      lines.push('');
+      lines.push(quotedPrintableEncode(input.htmlBody!));
+    }
+
+    // Attachments
+    for (const att of input.attachments!) {
+      lines.push(`--${boundary}`);
+      const disposition = att.cid ? 'inline' : 'attachment';
+      lines.push(`Content-Type: ${att.contentType}; name="${encodeHeaderValue(att.filename)}"`);
+      lines.push(`Content-Disposition: ${disposition}; filename="${encodeHeaderValue(att.filename)}"`);
+      lines.push('Content-Transfer-Encoding: base64');
+      if (att.cid) {
+        lines.push(`Content-ID: <${att.cid}>`);
+      }
+      lines.push('');
+      lines.push(base64Encode(att.content));
+    }
+    lines.push(`--${boundary}--`);
+  } else {
+    // Empty body
+    lines.push('Content-Type: text/plain; charset=utf-8');
+    lines.push('');
+  }
+
+  const raw = lines.join(CRLF);
+  return new TextEncoder().encode(raw);
+}
+
+// ── Helpers ──────────────────────────────────────────────────────────
+
+function generateBoundary(): string {
+  const bytes = crypto.getRandomValues(new Uint8Array(16));
+  const hex = Array.from(bytes)
+    .map((b) => b.toString(16).padStart(2, '0'))
+    .join('');
+  return `----=_Part_${hex}`;
+}
+
+function formatAddress(addr: { name?: string; email: string }): string {
+  if (addr.name) {
+    // RFC 5322 quoted-string for display name
+    const escaped = addr.name.replace(/\\/g, '\\\\').replace(/"/g, '\\"');
+    return `"${escaped}" <${addr.email}>`;
+  }
+  return addr.email;
+}
+
+function formatHeader(name: string, value: string): string {
+  const full = `${name}: ${value}`;
+  // RFC 5322 line length limit: fold at 76 chars
+  if (full.length <= 76) return full;
+  const parts: string[] = [];
+  let remaining = full;
+  let first = true;
+  while (remaining.length > 76) {
+    let breakAt = 76;
+    // Find a space to break at
+    const spaceIdx = remaining.lastIndexOf(' ', 76);
+    if (spaceIdx > (first ? name.length + 2 : 1)) {
+      breakAt = spaceIdx;
+    }
+    parts.push(remaining.slice(0, breakAt));
+    remaining = ' ' + remaining.slice(breakAt).trimStart();
+    first = false;
+  }
+  parts.push(remaining);
+  return parts.join(CRLF);
+}
+
+function encodeHeaderValue(value: string): string {
+  // Use RFC 2047 encoded-word if non-ASCII
+  if (/^[\x20-\x7e]*$/.test(value)) return value;
+  const encoded = Array.from(new TextEncoder().encode(value))
+    .map((b) => {
+      if (
+        (b >= 0x30 && b <= 0x39) || // 0-9
+        (b >= 0x41 && b <= 0x5a) || // A-Z
+        (b >= 0x61 && b <= 0x7a)    // a-z
+      ) {
+        return String.fromCharCode(b);
+      }
+      return '=' + b.toString(16).toUpperCase().padStart(2, '0');
+    })
+    .join('');
+  return `=?UTF-8?Q?${encoded}?=`;
+}
+
+function formatDate(date: Date): string {
+  // RFC 5322 date format
+  const days = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'];
+  const months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
+  const d = days[date.getUTCDay()];
+  const dd = date.getUTCDate();
+  const m = months[date.getUTCMonth()];
+  const y = date.getUTCFullYear();
+  const hh = date.getUTCHours().toString().padStart(2, '0');
+  const mm = date.getUTCMinutes().toString().padStart(2, '0');
+  const ss = date.getUTCSeconds().toString().padStart(2, '0');
+  return `${d}, ${dd} ${m} ${y} ${hh}:${mm}:${ss} +0000`;
+}
+
+export interface SmimeWrapInput {
+  from: { name?: string; email: string };
+  to: { name?: string; email: string }[];
+  cc?: { name?: string; email: string }[];
+  subject: string;
+  date?: Date;
+  messageId?: string;
+  inReplyTo?: string;
+  references?: string[];
+  smimeType: 'signed-data' | 'enveloped-data';
+}
+
+/**
+ * Wrap a CMS binary blob in a proper RFC 5322 / S/MIME message.
+ *
+ * The server needs RFC 5322 headers (From, To, Subject, etc.) to route
+ * the message; the CMS blob becomes the base64-encoded body.
+ */
+export function wrapCmsAsSmimeMessage(cmsBlob: Blob | ArrayBuffer | Uint8Array, input: SmimeWrapInput): Blob {
+  const lines: string[] = [];
+
+  lines.push(formatHeader('From', formatAddress(input.from)));
+  lines.push(formatHeader('To', input.to.map(formatAddress).join(', ')));
+  if (input.cc?.length) {
+    lines.push(formatHeader('Cc', input.cc.map(formatAddress).join(', ')));
+  }
+  lines.push(formatHeader('Subject', encodeHeaderValue(input.subject)));
+  lines.push(formatHeader('Date', formatDate(input.date ?? new Date())));
+  lines.push(formatHeader('Message-ID', input.messageId ?? `<${crypto.randomUUID()}@smime.local>`));
+  if (input.inReplyTo) {
+    lines.push(formatHeader('In-Reply-To', input.inReplyTo));
+  }
+  if (input.references?.length) {
+    lines.push(formatHeader('References', input.references.join(' ')));
+  }
+  lines.push('MIME-Version: 1.0');
+  lines.push(`Content-Type: application/pkcs7-mime; smime-type=${input.smimeType}; name="smime.p7m"`);
+  lines.push('Content-Transfer-Encoding: base64');
+  lines.push('Content-Disposition: attachment; filename="smime.p7m"');
+  lines.push('');
+
+  const headerPart = lines.join(CRLF);
+
+  // We'll combine header bytes + base64 body
+  const headerBytes = new TextEncoder().encode(headerPart);
+
+  return new Blob([headerBytes, cmsToBase64Blob(cmsBlob)], { type: 'message/rfc822' });
+}
+
+function cmsToBase64Blob(data: Blob | ArrayBuffer | Uint8Array): Blob {
+  let bytes: Uint8Array;
+  if (data instanceof Uint8Array) {
+    bytes = data;
+  } else if (data instanceof ArrayBuffer) {
+    bytes = new Uint8Array(data);
+  } else {
+    // Blob — we need sync; caller should have converted. Fallback to empty.
+    bytes = new Uint8Array(0);
+  }
+  const b64 = base64Encode(bytes.buffer as ArrayBuffer);
+  return new Blob([new TextEncoder().encode(b64 + CRLF)]);
+}
+
+/** Encode string as quoted-printable (RFC 2045). */
+export function quotedPrintableEncode(input: string): string {
+  const bytes = new TextEncoder().encode(input);
+  const lines: string[] = [];
+  let line = '';
+
+  for (const b of bytes) {
+    let encoded: string;
+    if (b === 0x0d || b === 0x0a) {
+      // Pass through CRLF as-is (handled below)
+      encoded = String.fromCharCode(b);
+    } else if (
+      b === 0x09 || // tab
+      (b >= 0x20 && b <= 0x7e && b !== 0x3d) // printable, not '='
+    ) {
+      encoded = String.fromCharCode(b);
+    } else {
+      encoded = '=' + b.toString(16).toUpperCase().padStart(2, '0');
+    }
+
+    if (b === 0x0a) {
+      // End current line (strip any trailing \r already added)
+      if (line.endsWith('\r')) {
+        line = line.slice(0, -1);
+      }
+      lines.push(line);
+      line = '';
+      continue;
+    }
+
+    if (line.length + encoded.length > 75) {
+      lines.push(line + '=');
+      line = encoded;
+    } else {
+      line += encoded;
+    }
+  }
+  lines.push(line);
+  return lines.join(CRLF);
+}
+
+/** Encode ArrayBuffer as base64 with line breaks at 76 chars. */
+export function base64Encode(data: ArrayBuffer): string {
+  const bytes = new Uint8Array(data);
+  let binary = '';
+  for (const b of bytes) {
+    binary += String.fromCharCode(b);
+  }
+  const b64 = btoa(binary);
+  const lines: string[] = [];
+  for (let i = 0; i < b64.length; i += 76) {
+    lines.push(b64.slice(i, i + 76));
+  }
+  return lines.join(CRLF);
+}

lib/smime/pkcs12-export.ts

@@ -0,0 +1,157 @@
+import * as asn1js from 'asn1js';
+import * as pkijs from 'pkijs';
+import { decryptPrivateKeyBytes } from './pkcs12-import';
+import type { SmimeKeyRecord } from './types';
+
+function stringToArrayBuffer(str: string): ArrayBuffer {
+  const buf = new ArrayBuffer(str.length);
+  const view = new Uint8Array(buf);
+  for (let i = 0; i < str.length; i++) {
+    view[i] = str.charCodeAt(i);
+  }
+  return buf;
+}
+
+/**
+ * Export an S/MIME key record as a PKCS#12 (.p12) file.
+ *
+ * Flow:
+ *  1. Decrypt the stored PKCS#8 private key bytes using the storage passphrase.
+ *  2. Build a PKCS#12 container with the private key, leaf cert, and chain.
+ *  3. Protect the PKCS#12 with the export passphrase.
+ *  4. Return the resulting bytes for browser download.
+ */
+export async function exportPkcs12(
+  record: SmimeKeyRecord,
+  storagePassphrase: string,
+  exportPassphrase: string,
+): Promise<ArrayBuffer> {
+  // Step 1: Decrypt the stored private key
+  const pkcs8Bytes = await decryptPrivateKeyBytes(record, storagePassphrase);
+
+  // Step 2: Parse the leaf certificate
+  const leafCertAsn1 = asn1js.fromBER(record.certificate);
+  if (leafCertAsn1.offset === -1) {
+    throw new Error('Failed to parse leaf certificate');
+  }
+  const leafCert = new pkijs.Certificate({ schema: leafCertAsn1.result });
+
+  // Parse chain certificates
+  const chainCerts = record.certificateChain.map((chainDer) => {
+    const chainAsn1 = asn1js.fromBER(chainDer);
+    if (chainAsn1.offset === -1) {
+      throw new Error('Failed to parse chain certificate');
+    }
+    return new pkijs.Certificate({ schema: chainAsn1.result });
+  });
+
+  const passwordBuf = stringToArrayBuffer(exportPassphrase);
+
+  // Step 3: Build the PKCS#12 structure
+  // Create key bag
+  const keyBag = new pkijs.PKCS8ShroudedKeyBag({
+    parsedValue: pkijs.PrivateKeyInfo.fromBER(pkcs8Bytes),
+  });
+
+  await keyBag.makeInternalValues({
+    password: passwordBuf,
+    contentEncryptionAlgorithm: {
+      name: 'AES-CBC',
+      length: 256,
+    } as unknown as Parameters<typeof keyBag.makeInternalValues>[0]['contentEncryptionAlgorithm'],
+    hmacHashAlgorithm: 'SHA-256',
+    iterationCount: 100_000,
+  });
+
+  const keyBagSafe = new pkijs.SafeBag({
+    bagId: '1.2.840.113549.1.12.10.1.2', // pkcs8ShroudedKeyBag
+    bagValue: keyBag,
+    bagAttributes: [
+      new pkijs.Attribute({
+        type: '1.2.840.113549.1.9.20', // friendlyName
+        values: [new asn1js.BmpString({ value: record.email })],
+      }),
+    ],
+  });
+
+  // Create cert bags
+  const certBags = [
+    new pkijs.SafeBag({
+      bagId: '1.2.840.113549.1.12.10.1.3', // certBag
+      bagValue: new pkijs.CertBag({
+        parsedValue: leafCert,
+      }),
+      bagAttributes: [
+        new pkijs.Attribute({
+          type: '1.2.840.113549.1.9.20',
+          values: [new asn1js.BmpString({ value: record.email })],
+        }),
+      ],
+    }),
+    ...chainCerts.map(
+      (cert) =>
+        new pkijs.SafeBag({
+          bagId: '1.2.840.113549.1.12.10.1.3',
+          bagValue: new pkijs.CertBag({
+            parsedValue: cert,
+          }),
+        }),
+    ),
+  ];
+
+  // Build authenticated safe with two SafeContents:
+  // 1. Key bag (password-encrypted)
+  // 2. Cert bags (unencrypted)
+  const authenticatedSafe = new pkijs.AuthenticatedSafe({
+    parsedValue: {
+      safeContents: [
+        {
+          privacyMode: 0, // no extra encryption — key bag is already shrouded
+          value: new pkijs.SafeContents({
+            safeBags: [keyBagSafe],
+          }),
+        },
+        {
+          privacyMode: 0,
+          value: new pkijs.SafeContents({
+            safeBags: certBags,
+          }),
+        },
+      ],
+    },
+  });
+
+  await authenticatedSafe.makeInternalValues({
+    safeContents: [{}, {}],
+  });
+
+  const pfx = new pkijs.PFX({
+    parsedValue: {
+      integrityMode: 0,
+      authenticatedSafe,
+    },
+  });
+
+  await pfx.makeInternalValues({
+    password: passwordBuf,
+    iterations: 100_000,
+    pbkdf2HashAlgorithm: 'SHA-256',
+    hmacHashAlgorithm: 'SHA-256',
+  });
+
+  // Step 4: Serialize to DER
+  return pfx.toSchema().toBER(false);
+}
+
+/** Trigger a browser download of the PKCS#12 file. */
+export function downloadPkcs12(p12Bytes: ArrayBuffer, filename: string): void {
+  const blob = new Blob([p12Bytes], { type: 'application/x-pkcs12' });
+  const url = URL.createObjectURL(blob);
+  const a = document.createElement('a');
+  a.href = url;
+  a.download = filename;
+  document.body.appendChild(a);
+  a.click();
+  document.body.removeChild(a);
+  URL.revokeObjectURL(url);
+}

lib/smime/pkcs12-import.ts

@@ -0,0 +1,303 @@
+import * as asn1js from 'asn1js';
+import * as pkijs from 'pkijs';
+import {
+  parseCertificateDer,
+  extractCertificateInfo,
+  classifyCapabilities,
+} from './certificate-utils';
+import type { SmimeKeyRecord, Pkcs12ImportResult } from './types';
+import { withLinerEngine } from './crypto-engine';
+
+const KDF_ITERATIONS = 600_000;
+const AES_KEY_LENGTH = 256;
+
+function stringToAB(str: string): ArrayBuffer {
+  const buf = new ArrayBuffer(str.length);
+  const view = new Uint8Array(buf);
+  for (let i = 0; i < str.length; i++) {
+    view[i] = str.charCodeAt(i);
+  }
+  return buf;
+}
+
+/** Parse a PKCS#12 (.p12/.pfx) file and produce an encrypted-at-rest key record. */
+export async function importPkcs12(
+  p12Bytes: ArrayBuffer,
+  p12Passphrase: string,
+  storagePassphrase: string,
+): Promise<Pkcs12ImportResult> {
+  // Parse PKCS#12 container
+  const asn1 = asn1js.fromBER(p12Bytes);
+  if (asn1.offset === -1) {
+    throw new Error('Invalid PKCS#12 file: ASN.1 parsing failed');
+  }
+
+  const pfx = new pkijs.PFX({ schema: asn1.result });
+
+  // Verify MAC if present
+  if (pfx.macData) {
+    const macOk = await pfx.parsedValue?.integrityMode === undefined || true;
+    // PKIjs handles MAC verification internally during parseInternalValues
+  }
+
+  // Use webcrypto-liner as the global engine for 3DES support.
+  // Many PKCS#12 files use pbeWithSHAAnd3-KeyTripleDES-CBC internally.
+  await withLinerEngine(async () => {
+    await pfx.parseInternalValues({
+      password: stringToAB(p12Passphrase),
+    });
+  });
+
+  // Extract certificates and private key from parsed PKCS#12
+  let leafCertDer: ArrayBuffer | null = null;
+  let leafCert: pkijs.Certificate | null = null;
+  const chainCertsDer: ArrayBuffer[] = [];
+  let privateKeyInfo: pkijs.PrivateKeyInfo | null = null;
+
+  if (!pfx.parsedValue?.authenticatedSafe) {
+    throw new Error('PKCS#12 file does not contain an authenticated safe');
+  }
+
+  // Parse the authenticated safe contents (inner SafeContents)
+  const authSafe = pfx.parsedValue.authenticatedSafe;
+  const safeContentsParams = authSafe.safeContents.map((ci: pkijs.ContentInfo) => {
+    // encryptedData (1.2.840.113549.1.7.6) needs the password
+    if (ci.contentType === '1.2.840.113549.1.7.6') {
+      return { password: stringToAB(p12Passphrase) };
+    }
+    return {};
+  });
+  await withLinerEngine(async () => {
+    await authSafe.parseInternalValues({ safeContents: safeContentsParams });
+  });
+
+  for (const safeContent of authSafe.parsedValue.safeContents) {
+    const sc = safeContent.value ?? safeContent.parsedValue;
+    if (!sc) continue;
+
+    for (const safeBag of sc.safeBags) {
+      // PKCS#12 bag types
+      switch (safeBag.bagId) {
+        case '1.2.840.113549.1.12.10.1.3': {
+          // CertBag
+          const certBag = safeBag.bagValue as pkijs.CertBag;
+
+          // parsedValue may already be a Certificate (built in-memory)
+          let cert: pkijs.Certificate | null = null;
+          let der: ArrayBuffer | null = null;
+
+          if (certBag.parsedValue instanceof pkijs.Certificate) {
+            cert = certBag.parsedValue;
+            der = cert.toSchema(true).toBER(false);
+          } else if (certBag.certId === '1.2.840.113549.1.9.22.1' && certBag.certValue) {
+            // x509Certificate — extract DER from the OCTET STRING
+            const certDerBytes = (certBag.certValue as asn1js.OctetString).valueBlock.valueHexView;
+            const certAsn1 = asn1js.fromBER(certDerBytes);
+            if (certAsn1.offset !== -1) {
+              cert = new pkijs.Certificate({ schema: certAsn1.result });
+              der = new Uint8Array(certDerBytes).buffer as ArrayBuffer;
+            }
+          }
+
+          if (cert && der) {
+            if (!leafCertDer) {
+              leafCertDer = der;
+              leafCert = cert;
+            } else {
+              chainCertsDer.push(der);
+            }
+          }
+          break;
+        }
+        case '1.2.840.113549.1.12.10.1.1': {
+          // KeyBag (unencrypted private key)
+          privateKeyInfo = safeBag.bagValue as pkijs.PrivateKeyInfo;
+          break;
+        }
+        case '1.2.840.113549.1.12.10.1.2': {
+          // PKCS8ShroudedKeyBag (encrypted private key)
+          const shroudedBag = safeBag.bagValue as pkijs.PKCS8ShroudedKeyBag;
+          if (shroudedBag.parsedValue) {
+            privateKeyInfo = shroudedBag.parsedValue;
+          } else {
+            // Decrypt shrouded key bag to get private key info
+            await withLinerEngine(async () => {
+              await (shroudedBag as unknown as { parseInternalValues(params: { password: ArrayBuffer }): Promise<void> }).parseInternalValues({
+                password: stringToAB(p12Passphrase),
+              });
+            });
+            if (shroudedBag.parsedValue) {
+              privateKeyInfo = shroudedBag.parsedValue;
+            }
+          }
+          break;
+        }
+      }
+    }
+  }
+
+  if (!leafCert || !leafCertDer) {
+    throw new Error('No certificate found in PKCS#12 file');
+  }
+  if (!privateKeyInfo) {
+    throw new Error('No private key found in PKCS#12 file');
+  }
+
+  // Extract PKCS#8 private key bytes
+  const pkcs8Bytes = privateKeyInfo.toSchema().toBER(false);
+
+  // Encrypt the private key for at-rest storage
+  const { encrypted, salt, iv } = await encryptPrivateKey(pkcs8Bytes, storagePassphrase);
+
+  // Extract certificate metadata
+  const certInfo = await extractCertificateInfo(leafCert, leafCertDer);
+  const capabilities = classifyCapabilities(leafCert);
+
+  const email = certInfo.emailAddresses[0] ?? '';
+
+  const keyRecord: SmimeKeyRecord = {
+    id: crypto.randomUUID(),
+    email: email.toLowerCase(),
+    certificate: leafCertDer,
+    certificateChain: chainCertsDer,
+    encryptedPrivateKey: encrypted,
+    salt,
+    iv,
+    kdfIterations: KDF_ITERATIONS,
+    issuer: certInfo.issuer,
+    subject: certInfo.subject,
+    serialNumber: certInfo.serialNumber,
+    notBefore: certInfo.notBefore,
+    notAfter: certInfo.notAfter,
+    fingerprint: certInfo.fingerprint,
+    algorithm: certInfo.algorithm,
+    capabilities,
+  };
+
+  return { keyRecord, certInfo };
+}
+
+// ── Private key encryption / decryption ──────────────────────────────
+
+async function deriveWrappingKey(
+  passphrase: string,
+  salt: ArrayBuffer,
+  iterations: number,
+): Promise<CryptoKey> {
+  const enc = new TextEncoder();
+  const keyMaterial = await crypto.subtle.importKey(
+    'raw',
+    enc.encode(passphrase),
+    'PBKDF2',
+    false,
+    ['deriveKey'],
+  );
+  return crypto.subtle.deriveKey(
+    { name: 'PBKDF2', salt, iterations, hash: 'SHA-256' },
+    keyMaterial,
+    { name: 'AES-GCM', length: AES_KEY_LENGTH },
+    false,
+    ['encrypt', 'decrypt'],
+  );
+}
+
+async function encryptPrivateKey(
+  pkcs8Bytes: ArrayBuffer,
+  passphrase: string,
+): Promise<{ encrypted: ArrayBuffer; salt: ArrayBuffer; iv: ArrayBuffer }> {
+  const salt = crypto.getRandomValues(new Uint8Array(32)).buffer;
+  const iv = crypto.getRandomValues(new Uint8Array(12)).buffer;
+  const wrappingKey = await deriveWrappingKey(passphrase, salt, KDF_ITERATIONS);
+  const encrypted = await crypto.subtle.encrypt(
+    { name: 'AES-GCM', iv },
+    wrappingKey,
+    pkcs8Bytes,
+  );
+  return { encrypted, salt, iv };
+}
+
+export interface UnlockedKeyPair {
+  signingKey: CryptoKey;
+  decryptionKey?: CryptoKey;
+}
+
+/** Decrypt stored PKCS#8 bytes and import as non-extractable CryptoKeys for signing and decryption. */
+export async function unlockPrivateKey(
+  record: SmimeKeyRecord,
+  passphrase: string,
+): Promise<UnlockedKeyPair> {
+  const wrappingKey = await deriveWrappingKey(
+    passphrase,
+    record.salt,
+    record.kdfIterations,
+  );
+
+  let pkcs8Bytes: ArrayBuffer;
+  try {
+    pkcs8Bytes = await crypto.subtle.decrypt(
+      { name: 'AES-GCM', iv: record.iv },
+      wrappingKey,
+      record.encryptedPrivateKey,
+    );
+  } catch {
+    throw new Error('Incorrect passphrase');
+  }
+
+  const isEcdsa = record.algorithm.startsWith('ECDSA');
+  const signAlg = isEcdsa
+    ? { name: 'ECDSA', namedCurve: ecdsaCurveFromAlg(record.algorithm) }
+    : { name: 'RSASSA-PKCS1-v1_5', hash: 'SHA-256' };
+  const decryptAlg = isEcdsa
+    ? { name: 'ECDH', namedCurve: ecdsaCurveFromAlg(record.algorithm) }
+    : { name: 'RSA-OAEP', hash: 'SHA-256' };
+  const decryptUsages: globalThis.KeyUsage[] = isEcdsa ? ['deriveBits'] : ['decrypt'];
+
+  // Import for signing
+  let signingKey: CryptoKey;
+  try {
+    signingKey = await crypto.subtle.importKey('pkcs8', pkcs8Bytes, signAlg, false, ['sign']);
+  } catch {
+    // Key may only support decryption (key-encipherment-only cert)
+    const decryptionKey = await crypto.subtle.importKey('pkcs8', pkcs8Bytes, decryptAlg, false, decryptUsages);
+    return { signingKey: decryptionKey, decryptionKey };
+  }
+
+  // Also import for decryption (separate CryptoKey handle required by Web Crypto)
+  let decryptionKey: CryptoKey | undefined;
+  try {
+    decryptionKey = await crypto.subtle.importKey('pkcs8', pkcs8Bytes, decryptAlg, false, decryptUsages);
+  } catch {
+    // Key may only support signing (digitalSignature-only cert)
+  }
+
+  return { signingKey, decryptionKey };
+}
+
+/** Get decrypted PKCS#8 bytes (for export flow). */
+export async function decryptPrivateKeyBytes(
+  record: SmimeKeyRecord,
+  passphrase: string,
+): Promise<ArrayBuffer> {
+  const wrappingKey = await deriveWrappingKey(
+    passphrase,
+    record.salt,
+    record.kdfIterations,
+  );
+
+  try {
+    return await crypto.subtle.decrypt(
+      { name: 'AES-GCM', iv: record.iv },
+      wrappingKey,
+      record.encryptedPrivateKey,
+    );
+  } catch {
+    throw new Error('Incorrect passphrase');
+  }
+}
+
+function ecdsaCurveFromAlg(alg: string): string {
+  if (alg.includes('P256') || alg.includes('P-256')) return 'P-256';
+  if (alg.includes('P384') || alg.includes('P-384')) return 'P-384';
+  if (alg.includes('P521') || alg.includes('P-521')) return 'P-521';
+  return 'P-256';
+}

lib/smime/smime-decrypt.ts

@@ -0,0 +1,376 @@
+/**
+ * Decrypt CMS EnvelopedData to recover the inner MIME content.
+ *
+ * Supports both issuerAndSerialNumber and subjectKeyIdentifier
+ * recipient identifier types per RFC 8551.
+ */
+
+import * as pkijs from 'pkijs';
+import * as asn1js from 'asn1js';
+import type { SmimeKeyRecord } from './types';
+import { getLinerCryptoEngine } from './crypto-engine';
+
+export interface DecryptionInput {
+  /** Raw CMS EnvelopedData bytes (DER) */
+  cmsBytes: ArrayBuffer;
+  /** All imported key records to try matching against */
+  keyRecords: SmimeKeyRecord[];
+  /** Unlocked CryptoKey map: keyRecordId → CryptoKey */
+  unlockedKeys: Map<string, CryptoKey>;
+}
+
+export interface DecryptionResult {
+  /** The decrypted inner MIME bytes */
+  mimeBytes: Uint8Array;
+  /** The key record that was used to decrypt */
+  keyRecordId: string;
+}
+
+/**
+ * Attempt to decrypt CMS EnvelopedData.
+ *
+ * Tries each matching key record against the recipient infos in the CMS structure.
+ *
+ * @throws Error if no matching key is found, key is locked, or decryption fails
+ */
+export async function smimeDecrypt(input: DecryptionInput): Promise<DecryptionResult> {
+  const { cmsBytes, keyRecords, unlockedKeys } = input;
+
+  // Parse the CMS ContentInfo wrapper
+  const contentInfo = parseContentInfo(cmsBytes);
+  const envelopedData = extractEnvelopedData(contentInfo);
+
+  // Find matching key records
+  const matchedRecords = findMatchingKeyRecords(envelopedData, keyRecords);
+
+  if (matchedRecords.length === 0) {
+    throw new Error('No imported S/MIME key matches any recipient in this encrypted message');
+  }
+
+  // Try each matched record
+  for (const { keyRecord, recipientIndex } of matchedRecords) {
+    const privateKey = unlockedKeys.get(keyRecord.id);
+    if (!privateKey) {
+      continue; // Key exists but isn't unlocked — skip, caller should unlock first
+    }
+
+    try {
+      const decrypted = await decryptWithKey(envelopedData, recipientIndex, privateKey, keyRecord);
+      return {
+        mimeBytes: new Uint8Array(decrypted),
+        keyRecordId: keyRecord.id,
+      };
+    } catch {
+      // This key didn't work, try the next one
+      continue;
+    }
+  }
+
+  // Check if we had matching records but none were unlocked
+  const hasLockedMatch = matchedRecords.some(m => !unlockedKeys.has(m.keyRecord.id));
+  if (hasLockedMatch) {
+    const lockedRecord = matchedRecords.find(m => !unlockedKeys.has(m.keyRecord.id))!;
+    throw new SmimeKeyLockedError(
+      'S/MIME key is locked. Unlock it to decrypt this message.',
+      lockedRecord.keyRecord.id,
+    );
+  }
+
+  throw new Error('Failed to decrypt message with any available key');
+}
+
+/**
+ * Get the key record IDs that could potentially decrypt a message.
+ * Useful for prompting the user to unlock the right key.
+ */
+export function findDecryptionCandidates(
+  cmsBytes: ArrayBuffer,
+  keyRecords: SmimeKeyRecord[],
+): string[] {
+  try {
+    const contentInfo = parseContentInfo(cmsBytes);
+    const envelopedData = extractEnvelopedData(contentInfo);
+    const matches = findMatchingKeyRecords(envelopedData, keyRecords);
+    return matches.map(m => m.keyRecord.id);
+  } catch {
+    return [];
+  }
+}
+
+export class SmimeKeyLockedError extends Error {
+  constructor(
+    message: string,
+    public readonly keyRecordId: string,
+  ) {
+    super(message);
+    this.name = 'SmimeKeyLockedError';
+  }
+}
+
+// --- Internal helpers ---
+
+/**
+ * Normalize raw blob bytes into DER-encoded CMS data.
+ *
+ * JMAP servers may return the CMS blob in various formats:
+ * - Raw DER binary (starts with 0x30 ASN.1 SEQUENCE tag)
+ * - Base64-encoded DER
+ * - Full MIME part with headers followed by base64 body
+ * - PEM-wrapped (-----BEGIN PKCS7-----)
+ *
+ * This function detects the format and returns raw DER bytes.
+ */
+export function normalizeCmsBytes(raw: ArrayBuffer): ArrayBuffer {
+  if (raw.byteLength === 0) {
+    return raw;
+  }
+
+  const bytes = new Uint8Array(raw);
+
+  // Already valid DER — starts with ASN.1 SEQUENCE tag
+  if (bytes[0] === 0x30) {
+    return raw;
+  }
+
+  let text = new TextDecoder().decode(raw);
+
+  const looksMostlyText = (() => {
+    const sample = text.slice(0, Math.min(text.length, 2048));
+    if (sample.length === 0) return false;
+    let printable = 0;
+    for (let i = 0; i < sample.length; i++) {
+      const code = sample.charCodeAt(i);
+      if (
+        code === 0x09 ||
+        code === 0x0a ||
+        code === 0x0d ||
+        (code >= 0x20 && code <= 0x7e)
+      ) {
+        printable++;
+      }
+    }
+    return printable / sample.length > 0.85;
+  })();
+
+  // Check if the blob contains MIME headers (e.g., server returned full part
+  // including Content-Transfer-Encoding header)
+  const headerEndMatch = text.match(/\r?\n\r?\n/);
+  const hasMimeHeaderHints = /content-type:|content-transfer-encoding:|mime-version:/i.test(text.slice(0, Math.min(text.length, 8192)));
+  if (looksMostlyText && headerEndMatch && headerEndMatch.index !== undefined && hasMimeHeaderHints) {
+    // Strip everything before the blank line separating headers from body
+    text = text.substring(headerEndMatch.index + headerEndMatch[0].length);
+  }
+
+  // Strip PEM armour if present
+  text = text
+    .replace(/-----BEGIN [A-Z0-9 ]+-----/g, '')
+    .replace(/-----END [A-Z0-9 ]+-----/g, '');
+
+  // Remove all whitespace and try base64 decode
+  text = text.replace(/\s/g, '');
+
+  if (text.length === 0) {
+    return raw;
+  }
+
+  try {
+    const binary = atob(text);
+    const decoded = new Uint8Array(binary.length);
+    for (let i = 0; i < binary.length; i++) decoded[i] = binary.charCodeAt(i);
+    if (decoded.length > 0 && decoded[0] === 0x30) {
+      return decoded.buffer as ArrayBuffer;
+    }
+  } catch { /* non-DER data, continue to fallback */ }
+
+  // Fallback: parse explicit MIME base64 sections
+  if (looksMostlyText) {
+    const originalText = new TextDecoder().decode(raw);
+    const sectionRegex = /content-transfer-encoding:\s*base64[\s\S]*?\r?\n\r?\n([\s\S]*?)(?:\r?\n--[^\r\n]+|$)/ig;
+    const sectionBlocks: string[] = [];
+    let sectionMatch: RegExpExecArray | null = null;
+    while ((sectionMatch = sectionRegex.exec(originalText)) !== null) {
+      sectionBlocks.push(sectionMatch[1]);
+    }
+
+    for (const block of sectionBlocks) {
+      const cleaned = block.replace(/\s/g, '');
+      if (cleaned.length < 8 || !/^[A-Za-z0-9+/=]+$/.test(cleaned)) continue;
+      try {
+        const binary = atob(cleaned);
+        const decoded = new Uint8Array(binary.length);
+        for (let i = 0; i < binary.length; i++) decoded[i] = binary.charCodeAt(i);
+        if (decoded.length > 0 && decoded[0] === 0x30) {
+          return decoded.buffer as ArrayBuffer;
+        }
+      } catch {
+        // try next section
+      }
+    }
+
+    // Last resort: find base64-like blocks and keep only DER-looking decodes
+    const base64Blocks = originalText.match(/[A-Za-z0-9+/=\r\n]{128,}/g) || [];
+    const cleaned = base64Blocks
+      .map(block => block.replace(/\s/g, ''))
+      .filter(block => block.length >= 128 && /^[A-Za-z0-9+/=]+$/.test(block));
+
+    cleaned.sort((a, b) => b.length - a.length);
+
+    for (const block of cleaned) {
+      try {
+        const binary = atob(block);
+        const decoded = new Uint8Array(binary.length);
+        for (let i = 0; i < binary.length; i++) decoded[i] = binary.charCodeAt(i);
+        if (decoded.length > 0 && decoded[0] === 0x30) {
+          return decoded.buffer as ArrayBuffer;
+        }
+      } catch {
+        // try next block
+      }
+    }
+  }
+
+  // Not decodable — return original bytes
+  return raw;
+}
+
+function parseContentInfo(der: ArrayBuffer): pkijs.ContentInfo {
+  const asn1 = asn1js.fromBER(der);
+  if (asn1.offset === -1) {
+    throw new Error('Invalid ASN.1 data — cannot parse CMS envelope');
+  }
+  try {
+    return new pkijs.ContentInfo({ schema: asn1.result });
+  } catch {
+    throw new Error('Invalid ASN.1 data — cannot parse CMS envelope');
+  }
+}
+
+function extractEnvelopedData(contentInfo: pkijs.ContentInfo): pkijs.EnvelopedData {
+  // OID 1.2.840.113549.1.7.3 = enveloped-data
+  if (contentInfo.contentType !== '1.2.840.113549.1.7.3') {
+    throw new Error(`Unexpected CMS content type: ${contentInfo.contentType}`);
+  }
+  return new pkijs.EnvelopedData({ schema: contentInfo.content });
+}
+
+interface RecipientMatch {
+  keyRecord: SmimeKeyRecord;
+  recipientIndex: number;
+}
+
+function findMatchingKeyRecords(
+  envelopedData: pkijs.EnvelopedData,
+  keyRecords: SmimeKeyRecord[],
+): RecipientMatch[] {
+  const matches: RecipientMatch[] = [];
+
+  for (let i = 0; i < envelopedData.recipientInfos.length; i++) {
+    const ri = envelopedData.recipientInfos[i];
+
+    // RecipientInfo is a wrapper: variant=1 → KeyTransRecipientInfo
+    const ktri = ri instanceof pkijs.KeyTransRecipientInfo
+      ? ri
+      : (ri as { variant?: number; value?: unknown }).variant === 1 && (ri as { value?: unknown }).value instanceof pkijs.KeyTransRecipientInfo
+        ? (ri as { value: pkijs.KeyTransRecipientInfo }).value
+        : null;
+
+    if (ktri) {
+      for (const keyRecord of keyRecords) {
+        if (matchesKeyTransRecipient(ktri, keyRecord)) {
+          matches.push({ keyRecord, recipientIndex: i });
+        }
+      }
+    }
+  }
+
+  return matches;
+}
+
+function matchesKeyTransRecipient(
+  recipientInfo: pkijs.KeyTransRecipientInfo,
+  keyRecord: SmimeKeyRecord,
+): boolean {
+  const rid = recipientInfo.rid;
+
+  // IssuerAndSerialNumber matching
+  if (rid instanceof pkijs.IssuerAndSerialNumber) {
+    try {
+      const certAsn1 = asn1js.fromBER(keyRecord.certificate);
+      if (certAsn1.offset === -1) return false;
+      const cert = new pkijs.Certificate({ schema: certAsn1.result });
+
+      // Compare serial numbers
+      const ridSerial = Buffer.from(rid.serialNumber.valueBlock.valueHexView).toString('hex');
+      const certSerial = Buffer.from(cert.serialNumber.valueBlock.valueHexView).toString('hex');
+      if (ridSerial !== certSerial) return false;
+
+      // Compare issuers (compare DER encoding)
+      const ridIssuerDer = rid.issuer.toSchema().toBER(false);
+      const certIssuerDer = cert.issuer.toSchema().toBER(false);
+      return arraysEqual(new Uint8Array(ridIssuerDer), new Uint8Array(certIssuerDer));
+    } catch {
+      return false;
+    }
+  }
+
+  // SubjectKeyIdentifier matching
+  if (rid instanceof asn1js.OctetString) {
+    try {
+      const certAsn1 = asn1js.fromBER(keyRecord.certificate);
+      if (certAsn1.offset === -1) return false;
+      const cert = new pkijs.Certificate({ schema: certAsn1.result });
+
+      // Find the SubjectKeyIdentifier extension
+      const skiExt = cert.extensions?.find(
+        ext => ext.extnID === '2.5.29.14', // id-ce-subjectKeyIdentifier
+      );
+      if (!skiExt) return false;
+
+      const skiValue = asn1js.fromBER(skiExt.extnValue.valueBlock.valueHexView);
+      if (skiValue.offset === -1) return false;
+      const ski = (skiValue.result as asn1js.OctetString).valueBlock.valueHexView;
+
+      return arraysEqual(
+        new Uint8Array(ski),
+        new Uint8Array(rid.valueBlock.valueHexView),
+      );
+    } catch {
+      return false;
+    }
+  }
+
+  return false;
+}
+
+function arraysEqual(a: Uint8Array, b: Uint8Array): boolean {
+  if (a.length !== b.length) return false;
+  for (let i = 0; i < a.length; i++) {
+    if (a[i] !== b[i]) return false;
+  }
+  return true;
+}
+
+async function decryptWithKey(
+  envelopedData: pkijs.EnvelopedData,
+  recipientIndex: number,
+  privateKey: CryptoKey,
+  keyRecord: SmimeKeyRecord,
+): Promise<ArrayBuffer> {
+  // Parse the certificate for pkijs
+  const certAsn1 = asn1js.fromBER(keyRecord.certificate);
+  const cert = new pkijs.Certificate({ schema: certAsn1.result });
+
+  // Use webcrypto-liner engine for legacy algorithm support (e.g. 3DES)
+  const cryptoEngine = getLinerCryptoEngine();
+
+  const result = await envelopedData.decrypt(
+    recipientIndex,
+    {
+      recipientCertificate: cert,
+      recipientPrivateKey: privateKey,
+    },
+    cryptoEngine,
+  );
+
+  return result;
+}

lib/smime/smime-detect.ts

@@ -0,0 +1,194 @@
+/**
+ * Detect S/MIME content in an email message.
+ *
+ * Checks Content-Type headers, bodyStructure, and attachment metadata
+ * to determine if a message contains CMS signed or encrypted content.
+ */
+
+export type SmimeContentType =
+  | 'enveloped-data'   // encrypted
+  | 'signed-data'      // opaque signed
+  | 'detached-sig'     // multipart/signed (deferred in v1)
+  | null;
+
+export interface SmimeDetectionResult {
+  /** Primary S/MIME content type detected, or null if none */
+  type: SmimeContentType;
+  /** The blobId to fetch for CMS processing (enveloped-data or signed-data) */
+  blobId?: string;
+  /** The partId containing the CMS data */
+  partId?: string;
+  /** Whether this is a v1-supported type */
+  supported: boolean;
+}
+
+interface EmailBodyPart {
+  partId?: string;
+  blobId?: string;
+  type?: string;
+  name?: string;
+  disposition?: string;
+  subParts?: EmailBodyPart[];
+  headers?: Array<{ name: string; value: string }>;
+}
+
+/**
+ * Detect S/MIME content from email metadata.
+ *
+ * @param contentType - The top-level Content-Type header value
+ * @param bodyStructure - The JMAP bodyStructure tree
+ * @param attachments - Flat list of attachment parts (from `attachments` property)
+ */
+export function detectSmime(
+  contentType?: string,
+  bodyStructure?: EmailBodyPart | null,
+  attachments?: EmailBodyPart[],
+): SmimeDetectionResult {
+  const noResult: SmimeDetectionResult = { type: null, supported: false };
+
+  // 1. Check top-level Content-Type header
+  if (contentType) {
+    const ct = contentType.toLowerCase();
+
+    if (ct.includes('application/pkcs7-mime') || ct.includes('application/x-pkcs7-mime')) {
+      if (ct.includes('smime-type=enveloped-data')) {
+        const part = findCmsPart(bodyStructure, 'enveloped-data');
+        return {
+          type: 'enveloped-data',
+          blobId: part?.blobId,
+          partId: part?.partId,
+          supported: true,
+        };
+      }
+      if (ct.includes('smime-type=signed-data')) {
+        const part = findCmsPart(bodyStructure, 'signed-data');
+        return {
+          type: 'signed-data',
+          blobId: part?.blobId,
+          partId: part?.partId,
+          supported: true,
+        };
+      }
+      // Generic pkcs7-mime without explicit smime-type — try bodyStructure
+      const part = findCmsPart(bodyStructure, null);
+      if (part) {
+        const partType = inferSmimeType(part);
+        return {
+          type: partType,
+          blobId: part.blobId,
+          partId: part.partId,
+          supported: partType === 'enveloped-data' || partType === 'signed-data',
+        };
+      }
+    }
+
+    if (ct.includes('multipart/signed') && ct.includes('application/pkcs7-signature')) {
+      return { type: 'detached-sig', supported: false };
+    }
+  }
+
+  // 2. Walk bodyStructure tree
+  if (bodyStructure) {
+    const result = walkBodyStructure(bodyStructure);
+    if (result) return result;
+  }
+
+  // 3. Check attachment list for .p7m files
+  if (attachments) {
+    for (const att of attachments) {
+      const type = att.type?.toLowerCase() || '';
+      const name = att.name?.toLowerCase() || '';
+
+      if (type.includes('application/pkcs7-mime') || type.includes('application/x-pkcs7-mime')) {
+        const smimeType = inferSmimeTypeFromContentType(type);
+        return {
+          type: smimeType,
+          blobId: att.blobId,
+          partId: att.partId,
+          supported: smimeType === 'enveloped-data' || smimeType === 'signed-data',
+        };
+      }
+
+      if (name.endsWith('.p7m')) {
+        return {
+          type: 'enveloped-data', // .p7m is ambiguous but commonly encrypted
+          blobId: att.blobId,
+          partId: att.partId,
+          supported: true,
+        };
+      }
+
+      if (name.endsWith('.p7s')) {
+        return { type: 'detached-sig', blobId: att.blobId, partId: att.partId, supported: false };
+      }
+    }
+  }
+
+  return noResult;
+}
+
+function walkBodyStructure(part: EmailBodyPart): SmimeDetectionResult | null {
+  const type = part.type?.toLowerCase() || '';
+
+  if (type.includes('application/pkcs7-mime') || type.includes('application/x-pkcs7-mime')) {
+    const smimeType = inferSmimeTypeFromContentType(type);
+    return {
+      type: smimeType,
+      blobId: part.blobId,
+      partId: part.partId,
+      supported: smimeType === 'enveloped-data' || smimeType === 'signed-data',
+    };
+  }
+
+  if (type === 'multipart/signed') {
+    // Check for pkcs7-signature protocol in subparts
+    if (part.subParts?.some(sp => sp.type?.toLowerCase().includes('application/pkcs7-signature'))) {
+      return { type: 'detached-sig', supported: false };
+    }
+  }
+
+  if (part.subParts) {
+    for (const sub of part.subParts) {
+      const result = walkBodyStructure(sub);
+      if (result) return result;
+    }
+  }
+
+  return null;
+}
+
+function findCmsPart(bodyStructure: EmailBodyPart | null | undefined, smimeType: string | null): EmailBodyPart | null {
+  if (!bodyStructure) return null;
+
+  const type = bodyStructure.type?.toLowerCase() || '';
+  if (type.includes('application/pkcs7-mime') || type.includes('application/x-pkcs7-mime')) {
+    // JMAP bodyStructure.type may not include smime-type parameter,
+    // so accept any pkcs7-mime part when the smime-type was already
+    // determined from the Content-Type header.
+    return bodyStructure;
+  }
+
+  if (bodyStructure.subParts) {
+    for (const sub of bodyStructure.subParts) {
+      const found = findCmsPart(sub, smimeType);
+      if (found) return found;
+    }
+  }
+
+  return null;
+}
+
+function inferSmimeType(part: EmailBodyPart): SmimeContentType {
+  return inferSmimeTypeFromContentType(part.type || '');
+}
+
+function inferSmimeTypeFromContentType(ct: string): SmimeContentType {
+  const lower = ct.toLowerCase();
+  if (lower.includes('smime-type=enveloped-data')) return 'enveloped-data';
+  if (lower.includes('smime-type=signed-data')) return 'signed-data';
+  // Default for generic pkcs7-mime: assume enveloped-data (most common)
+  if (lower.includes('application/pkcs7-mime') || lower.includes('application/x-pkcs7-mime')) {
+    return 'enveloped-data';
+  }
+  return null;
+}

lib/smime/smime-encrypt.ts

@@ -0,0 +1,81 @@
+import * as asn1js from 'asn1js';
+import * as pkijs from 'pkijs';
+import { parseCertificateDer } from './certificate-utils';
+
+/**
+ * Produce CMS EnvelopedData for the given MIME content.
+ *
+ * Content type: application/pkcs7-mime; smime-type=enveloped-data
+ *
+ * Always includes the sender's cert so the sender can decrypt their Sent mail.
+ */
+export async function smimeEncrypt(
+  mimeBytes: Uint8Array,
+  recipientCertsDer: ArrayBuffer[],
+  senderCertDer: ArrayBuffer,
+  useAes128?: boolean,
+): Promise<Blob> {
+  // Combine recipient + sender certs, deduplicate by DER bytes
+  const allCertDers = deduplicateCerts([...recipientCertsDer, senderCertDer]);
+
+  if (allCertDers.length === 0) {
+    throw new Error('No recipient certificates provided');
+  }
+
+  // Parse all certificates
+  const recipientCerts = allCertDers.map((der) => parseCertificateDer(der));
+
+  // Build EnvelopedData
+  const cmsEnveloped = new pkijs.EnvelopedData();
+
+  // Add recipient info for each certificate
+  for (const cert of recipientCerts) {
+    cmsEnveloped.addRecipientByCertificate(cert, {
+      oaepHashAlgorithm: 'SHA-256',
+    }, undefined, new pkijs.CryptoEngine({
+      crypto: crypto,
+      subtle: crypto.subtle,
+      name: 'webcrypto',
+    }));
+  }
+
+  // Encrypt the content
+  const contentEncryptionAlgorithm = useAes128
+    ? { name: 'AES-GCM', length: 128 }
+    : { name: 'AES-GCM', length: 256 };
+
+  await cmsEnveloped.encrypt(contentEncryptionAlgorithm, mimeBytes.buffer.slice(mimeBytes.byteOffset, mimeBytes.byteOffset + mimeBytes.byteLength) as ArrayBuffer, new pkijs.CryptoEngine({
+    crypto: crypto,
+    subtle: crypto.subtle,
+    name: 'webcrypto',
+  }));
+
+  // Wrap in ContentInfo
+  const cms = new pkijs.ContentInfo({
+    contentType: '1.2.840.113549.1.7.3', // id-envelopedData
+    content: cmsEnveloped.toSchema(),
+  });
+
+  const cmsBytes = cms.toSchema().toBER(false);
+  return new Blob([cmsBytes], { type: 'application/pkcs7-mime; smime-type=enveloped-data' });
+}
+
+/** Remove duplicate DER-encoded certificates based on byte equality. */
+function deduplicateCerts(certs: ArrayBuffer[]): ArrayBuffer[] {
+  const seen = new Set<string>();
+  const result: ArrayBuffer[] = [];
+  for (const cert of certs) {
+    const key = arrayBufferToHex(cert);
+    if (!seen.has(key)) {
+      seen.add(key);
+      result.push(cert);
+    }
+  }
+  return result;
+}
+
+function arrayBufferToHex(buf: ArrayBuffer): string {
+  return Array.from(new Uint8Array(buf))
+    .map((b) => b.toString(16).padStart(2, '0'))
+    .join('');
+}

lib/smime/smime-sign.ts

@@ -0,0 +1,71 @@
+import * as asn1js from 'asn1js';
+import * as pkijs from 'pkijs';
+import { Convert } from 'pvtsutils';
+import { parseCertificateDer } from './certificate-utils';
+
+/**
+ * Produce an opaque CMS SignedData wrapping the given MIME content.
+ *
+ * Content type: application/pkcs7-mime; smime-type=signed-data
+ * This is the "opaque" form — the content is embedded inside the CMS structure.
+ */
+export async function smimeSign(
+  mimeBytes: Uint8Array,
+  privateKey: CryptoKey,
+  signerCertDer: ArrayBuffer,
+  chainCertsDer: ArrayBuffer[] = [],
+): Promise<Blob> {
+  // Parse signer certificate
+  const signerCert = parseCertificateDer(signerCertDer);
+
+  // Parse chain certificates
+  const chainCerts = chainCertsDer.map((der) => parseCertificateDer(der));
+
+  // Build CMS SignedData
+  const cmsSigned = new pkijs.SignedData({
+    version: 1,
+    encapContentInfo: new pkijs.EncapsulatedContentInfo({
+      eContentType: '1.2.840.113549.1.7.1', // id-data
+      eContent: new asn1js.OctetString({ valueHex: new Uint8Array(mimeBytes.buffer.slice(mimeBytes.byteOffset, mimeBytes.byteOffset + mimeBytes.byteLength)) }),
+    }),
+    signerInfos: [
+      new pkijs.SignerInfo({
+        version: 1,
+        sid: new pkijs.IssuerAndSerialNumber({
+          issuer: signerCert.issuer,
+          serialNumber: signerCert.serialNumber,
+        }),
+      }),
+    ],
+    certificates: [signerCert, ...chainCerts],
+  });
+
+  // Determine signing algorithm from the key
+  const algorithm = privateKey.algorithm;
+  const hashAlgorithm = 'SHA-256';
+
+  let signAlg: string;
+  if (algorithm.name === 'RSASSA-PKCS1-v1_5' || algorithm.name === 'RSA-PSS') {
+    signAlg = algorithm.name;
+  } else if (algorithm.name === 'ECDSA') {
+    signAlg = 'ECDSA';
+  } else {
+    signAlg = 'RSASSA-PKCS1-v1_5';
+  }
+
+  // Sign
+  await cmsSigned.sign(privateKey, 0, hashAlgorithm, undefined, new pkijs.CryptoEngine({
+    crypto: crypto,
+    subtle: crypto.subtle,
+    name: 'webcrypto',
+  }));
+
+  // Wrap in ContentInfo
+  const cms = new pkijs.ContentInfo({
+    contentType: '1.2.840.113549.1.7.2', // id-signedData
+    content: cmsSigned.toSchema(true),
+  });
+
+  const cmsBytes = cms.toSchema().toBER(false);
+  return new Blob([cmsBytes], { type: 'application/pkcs7-mime; smime-type=signed-data' });
+}

lib/smime/smime-verify.ts

@@ -0,0 +1,219 @@
+/**
+ * Verify CMS SignedData (opaque signed) and extract the inner content.
+ *
+ * v1 performs cryptographic signature validation and cert validity checks
+ * but does NOT implement full trust-chain or revocation validation.
+ */
+
+import * as pkijs from 'pkijs';
+import * as asn1js from 'asn1js';
+import { extractCertificateInfo } from './certificate-utils';
+import type { SmimeStatus, SmimePublicCert } from './types';
+
+export interface VerificationResult {
+  /** The inner MIME bytes extracted from the opaque SignedData */
+  mimeBytes: Uint8Array;
+  /** Full S/MIME status for display */
+  status: SmimeStatus;
+}
+
+/**
+ * Verify a CMS SignedData structure and extract the encapsulated content.
+ *
+ * @param cmsBytes - Raw DER-encoded CMS SignedData
+ * @param fromHeader - The From header email address for signer identity matching
+ */
+export async function smimeVerify(
+  cmsBytes: ArrayBuffer,
+  fromHeader?: string,
+): Promise<VerificationResult> {
+  const contentInfo = parseContentInfo(cmsBytes);
+  const signedData = extractSignedData(contentInfo);
+
+  // Extract inner content
+  const innerContent = extractInnerContent(signedData);
+
+  // Extract signer certificate
+  const signerCert = extractSignerCertificate(signedData);
+  if (!signerCert) {
+    return {
+      mimeBytes: innerContent,
+      status: {
+        isSigned: true,
+        isEncrypted: false,
+        signatureValid: false,
+        signatureError: 'Signer certificate not found in CMS structure',
+      },
+    };
+  }
+
+  // Verify the signature cryptographically
+  let signatureValid = false;
+  let signatureError: string | undefined;
+
+  try {
+    const cryptoEngine = new pkijs.CryptoEngine({
+      crypto: crypto,
+      subtle: crypto.subtle,
+      name: 'webcrypto',
+    });
+
+    const verifyResult = await signedData.verify(
+      {
+        signer: 0,
+        checkChain: false, // v1: no trust-chain validation
+      },
+      cryptoEngine,
+    );
+    signatureValid = verifyResult;
+  } catch (err) {
+    signatureError = err instanceof Error ? err.message : 'Signature verification failed';
+  }
+
+  // Extract certificate info for display
+  const certDer = signerCert.toSchema(true).toBER(false);
+  const certInfo = await extractCertificateInfo(signerCert, certDer);
+
+  // Check certificate validity period
+  const now = new Date();
+  const notBefore = new Date(certInfo.notBefore);
+  const notAfter = new Date(certInfo.notAfter);
+  const certExpired = now > notAfter;
+  const certNotYetValid = now < notBefore;
+
+  if (certExpired && !signatureError) {
+    signatureError = 'Signer certificate has expired';
+  }
+  if (certNotYetValid && !signatureError) {
+    signatureError = 'Signer certificate is not yet valid';
+  }
+
+  // Build the signer public cert object
+  const signerEmail = certInfo.emailAddresses[0] ?? '';
+  const signerPublicCert: SmimePublicCert = {
+    id: `signer-${certInfo.fingerprint}`,
+    email: signerEmail.toLowerCase(),
+    certificate: certDer,
+    issuer: certInfo.issuer,
+    subject: certInfo.subject,
+    notBefore: certInfo.notBefore,
+    notAfter: certInfo.notAfter,
+    fingerprint: certInfo.fingerprint,
+    source: 'signed-email',
+  };
+
+  // Check signer identity vs From header
+  let signerEmailMatch: boolean | undefined;
+  if (fromHeader && signerEmail) {
+    signerEmailMatch = fromHeader.toLowerCase() === signerEmail.toLowerCase();
+  }
+
+  return {
+    mimeBytes: innerContent,
+    status: {
+      isSigned: true,
+      isEncrypted: false,
+      signatureValid: signatureValid && !certExpired && !certNotYetValid,
+      signatureError,
+      signerCert: signerPublicCert,
+      signerEmailMatch,
+    },
+  };
+}
+
+// --- Internal helpers ---
+
+function parseContentInfo(der: ArrayBuffer): pkijs.ContentInfo {
+  const asn1 = asn1js.fromBER(der);
+  if (asn1.offset === -1) {
+    throw new Error('Invalid ASN.1 data — cannot parse CMS structure');
+  }
+  return new pkijs.ContentInfo({ schema: asn1.result });
+}
+
+function extractSignedData(contentInfo: pkijs.ContentInfo): pkijs.SignedData {
+  // OID 1.2.840.113549.1.7.2 = signed-data
+  if (contentInfo.contentType !== '1.2.840.113549.1.7.2') {
+    throw new Error(`Unexpected CMS content type: ${contentInfo.contentType}`);
+  }
+  return new pkijs.SignedData({ schema: contentInfo.content });
+}
+
+function extractInnerContent(signedData: pkijs.SignedData): Uint8Array {
+  const eContent = signedData.encapContentInfo?.eContent;
+  if (!eContent) {
+    throw new Error('No encapsulated content in SignedData (detached signature not supported)');
+  }
+
+  if (eContent instanceof asn1js.OctetString) {
+    // Constructed OCTET STRING: data lives in child OctetStrings
+    const children = (eContent.valueBlock as unknown as { value?: asn1js.OctetString[] }).value;
+    if (children?.length) {
+      const chunks = children.map(c => new Uint8Array(c.valueBlock.valueHexView));
+      const total = chunks.reduce((sum, c) => sum + c.length, 0);
+      const result = new Uint8Array(total);
+      let offset = 0;
+      for (const chunk of chunks) {
+        result.set(chunk, offset);
+        offset += chunk.length;
+      }
+      return result;
+    }
+    // Primitive OCTET STRING: data is directly in valueHexView
+    return new Uint8Array(eContent.valueBlock.valueHexView);
+  }
+
+  throw new Error('Unable to extract content from SignedData');
+}
+
+function extractSignerCertificate(signedData: pkijs.SignedData): pkijs.Certificate | null {
+  if (!signedData.signerInfos?.length || !signedData.certificates?.length) {
+    return null;
+  }
+
+  const signerInfo = signedData.signerInfos[0];
+  const sid = signerInfo.sid;
+
+  // IssuerAndSerialNumber matching
+  if (sid instanceof pkijs.IssuerAndSerialNumber) {
+    for (const certItem of signedData.certificates) {
+      if (!(certItem instanceof pkijs.Certificate)) continue;
+      const cert = certItem;
+
+      // Compare serial numbers
+      const sidSerial = toHex(sid.serialNumber.valueBlock.valueHexView);
+      const certSerial = toHex(cert.serialNumber.valueBlock.valueHexView);
+      if (sidSerial !== certSerial) continue;
+
+      // Compare issuers
+      const sidIssuerDer = new Uint8Array(sid.issuer.toSchema().toBER(false));
+      const certIssuerDer = new Uint8Array(cert.issuer.toSchema().toBER(false));
+      if (arraysEqual(sidIssuerDer, certIssuerDer)) {
+        return cert;
+      }
+    }
+  }
+
+  // If only one certificate is present, use it as fallback
+  if (signedData.certificates.length === 1) {
+    const cert = signedData.certificates[0];
+    if (cert instanceof pkijs.Certificate) return cert;
+  }
+
+  return null;
+}
+
+function toHex(buffer: ArrayBuffer | ArrayBufferView): string {
+  const bytes = buffer instanceof ArrayBuffer
+    ? new Uint8Array(buffer)
+    : new Uint8Array(buffer.buffer, buffer.byteOffset, buffer.byteLength);
+  return Array.from(bytes).map(b => b.toString(16).padStart(2, '0')).join('');
+}
+
+function arraysEqual(a: Uint8Array, b: Uint8Array): boolean {
+  if (a.length !== b.length) return false;
+  for (let i = 0; i < a.length; i++) {
+    if (a[i] !== b[i]) return false;
+  }
+  return true;
+}

lib/smime/types.ts

@@ -0,0 +1,80 @@
+/** Stored record for an imported S/MIME private key + certificate. */
+export interface SmimeKeyRecord {
+  id: string;
+  email: string;
+  certificate: ArrayBuffer;           // DER-encoded X.509 leaf cert
+  certificateChain: ArrayBuffer[];    // DER-encoded intermediates
+  encryptedPrivateKey: ArrayBuffer;   // AES-GCM wrapped PKCS#8 bytes
+  salt: ArrayBuffer;                  // PBKDF2 salt
+  iv: ArrayBuffer;                    // AES-GCM IV
+  kdfIterations: number;
+  issuer: string;
+  subject: string;
+  serialNumber: string;
+  notBefore: string;                  // ISO 8601
+  notAfter: string;                   // ISO 8601
+  fingerprint: string;               // SHA-256 hex of DER cert
+  algorithm: string;                  // e.g. "RSA-2048", "RSA-4096", "ECDSA-P256"
+  capabilities: SmimeKeyCapabilities;
+}
+
+/** What a certificate can be used for based on KeyUsage/ExtendedKeyUsage. */
+export interface SmimeKeyCapabilities {
+  canSign: boolean;
+  canEncrypt: boolean;
+}
+
+/** Runtime-only unlocked private key handle (never persisted). */
+export interface SmimeUnlockedKey {
+  id: string;
+  email: string;
+  privateKey: CryptoKey; // imported as non-extractable
+}
+
+/** A recipient or contact public certificate. */
+export interface SmimePublicCert {
+  id: string;
+  email: string;
+  certificate: ArrayBuffer;           // DER-encoded X.509
+  issuer: string;
+  subject: string;
+  notBefore: string;
+  notAfter: string;
+  fingerprint: string;
+  source: 'manual' | 'contact' | 'signed-email';
+  contactId?: string;
+}
+
+/** Status of S/MIME processing for a single email message. */
+export interface SmimeStatus {
+  isSigned: boolean;
+  isEncrypted: boolean;
+  signatureValid?: boolean;
+  signatureError?: string;
+  signerCert?: SmimePublicCert;
+  signerEmailMatch?: boolean;
+  decryptionSuccess?: boolean;
+  decryptionError?: string;
+  unsupportedReason?: string;
+}
+
+/** Metadata extracted from a parsed X.509 certificate. */
+export interface CertificateInfo {
+  subject: string;
+  issuer: string;
+  serialNumber: string;
+  notBefore: string;
+  notAfter: string;
+  fingerprint: string;
+  algorithm: string;
+  keyUsage?: string[];
+  extendedKeyUsage?: string[];
+  emailAddresses: string[];
+  capabilities: SmimeKeyCapabilities;
+}
+
+/** Result of PKCS#12 import parsing. */
+export interface Pkcs12ImportResult {
+  keyRecord: SmimeKeyRecord;
+  certInfo: CertificateInfo;
+}

lib/tnef.ts

@@ -0,0 +1,398 @@
+/**
+ * Minimal TNEF (Transport Neutral Encapsulation Format) parser.
+ *
+ * Parses winmail.dat files sent by Microsoft Outlook to extract
+ * the HTML body, plain text body, and embedded attachments.
+ *
+ * Reference: MS-OXTNEF / MS-TNEF specification.
+ */
+
+import { debug } from '@/lib/debug';
+
+// TNEF signature
+const TNEF_SIGNATURE = 0x223E9F78;
+
+// Attribute levels
+const LVL_MESSAGE = 0x01;
+const LVL_ATTACHMENT = 0x02;
+
+// Message-level attribute IDs
+const attBody = 0x0002800C;
+const attMAPIProps = 0x00069003;
+
+// Attachment-level attribute IDs
+const attAttachRenddata = 0x00069002;
+const attAttachData = 0x0006800F;
+const attAttachTitle = 0x00018010;
+const attAttachment = 0x00069005; // MAPI props for attachments
+
+// MAPI property types
+const PT_SHORT = 0x0002;
+const PT_LONG = 0x0003;
+const PT_BOOLEAN = 0x000B;
+const PT_STRING8 = 0x001E;
+const PT_UNICODE = 0x001F;
+const PT_BINARY = 0x0102;
+const PT_SYSTIME = 0x0040;
+const PT_CLSID = 0x0048;
+const PT_I8 = 0x0014;
+
+// Multi-value flag
+const MV_FLAG = 0x1000;
+
+// MAPI property IDs
+const PR_BODY = 0x1000;
+const PR_BODY_HTML = 0x1013;
+const PR_ATTACH_LONG_FILENAME = 0x3707;
+const PR_ATTACH_MIME_TAG = 0x370E;
+const PR_ATTACH_DATA_BIN = 0x3701;
+
+export interface TnefAttachment {
+  name: string;
+  mimeType: string;
+  data: Uint8Array;
+}
+
+export interface TnefResult {
+  body: string | null;
+  htmlBody: string | null;
+  attachments: TnefAttachment[];
+}
+
+class BinaryReader {
+  private view: DataView;
+  private offset: number;
+  private bytes: Uint8Array;
+
+  constructor(data: Uint8Array) {
+    this.bytes = data;
+    this.view = new DataView(data.buffer, data.byteOffset, data.byteLength);
+    this.offset = 0;
+  }
+
+  readUint8(): number {
+    const val = this.view.getUint8(this.offset);
+    this.offset += 1;
+    return val;
+  }
+
+  readUint16LE(): number {
+    const val = this.view.getUint16(this.offset, true);
+    this.offset += 2;
+    return val;
+  }
+
+  readUint32LE(): number {
+    const val = this.view.getUint32(this.offset, true);
+    this.offset += 4;
+    return val;
+  }
+
+  readBytes(length: number): Uint8Array {
+    const slice = this.bytes.slice(this.offset, this.offset + length);
+    this.offset += length;
+    return slice;
+  }
+
+  skip(n: number): void {
+    this.offset += n;
+  }
+
+  get remaining(): number {
+    return this.bytes.byteLength - this.offset;
+  }
+}
+
+/** Padding needed to align to 4-byte boundary */
+function pad4(len: number): number {
+  return (4 - (len % 4)) % 4;
+}
+
+/** Read a single MAPI property value (fixed-length types only) */
+function readMAPIFixedValue(r: BinaryReader, propType: number): Uint8Array | number | null {
+  switch (propType) {
+    case PT_SHORT: {
+      const val = r.readUint16LE();
+      r.skip(2); // padded to 4 bytes
+      return val;
+    }
+    case PT_LONG:
+    case PT_BOOLEAN:
+      return r.readUint32LE();
+    case PT_I8:
+    case PT_SYSTIME:
+      return r.readBytes(8);
+    case PT_CLSID:
+      return r.readBytes(16);
+    default:
+      // Unknown/unsupported type — try to read as fixed 4 bytes
+      if (r.remaining >= 4) {
+        return r.readBytes(4);
+      }
+      return null;
+  }
+}
+
+/** Read a variable-length MAPI value (length-prefixed with padding) */
+function readMAPIVarValue(r: BinaryReader): Uint8Array | null {
+  if (r.remaining < 4) return null;
+  const length = r.readUint32LE();
+  if (length > r.remaining) return null;
+  const data = r.readBytes(length);
+  r.skip(pad4(length));
+  return data;
+}
+
+/** Check if a base property type is variable-length */
+function isVarLengthType(baseType: number): boolean {
+  return baseType === PT_STRING8 || baseType === PT_UNICODE || baseType === PT_BINARY;
+}
+
+/** Decode a MAPI string (PT_STRING8 or PT_UNICODE) from raw bytes */
+function decodeMAPIString(data: Uint8Array, propType: number): string {
+  if (propType === PT_UNICODE) {
+    let len = data.byteLength;
+    // Strip null terminator (2 bytes for UTF-16)
+    if (len >= 2 && data[len - 1] === 0 && data[len - 2] === 0) {
+      len -= 2;
+    }
+    return new TextDecoder('utf-16le').decode(data.subarray(0, len));
+  }
+  let len = data.byteLength;
+  if (len >= 1 && data[len - 1] === 0) {
+    len -= 1;
+  }
+  return new TextDecoder('utf-8').decode(data.subarray(0, len));
+}
+
+/** Parse MAPI properties from a raw attribute data block */
+function parseMAPIProps(data: Uint8Array): Map<number, { type: number; value: Uint8Array | number | null }> {
+  const props = new Map<number, { type: number; value: Uint8Array | number | null }>();
+  const r = new BinaryReader(data);
+
+  if (r.remaining < 4) return props;
+  const count = r.readUint32LE();
+
+  for (let i = 0; i < count && r.remaining >= 4; i++) {
+    const propType = r.readUint16LE();
+    const propID = r.readUint16LE();
+
+    // Named properties (ID >= 0x8000) carry extra GUID + name data
+    if (propID >= 0x8000) {
+      if (r.remaining < 20) break;
+      r.skip(16); // GUID
+      const kind = r.readUint32LE();
+      if (kind === 0) {
+        if (r.remaining < 4) break;
+        r.skip(4); // named-by-ID
+      } else {
+        if (r.remaining < 4) break;
+        const nameLen = r.readUint32LE();
+        if (nameLen > r.remaining) break;
+        r.skip(nameLen);
+        r.skip(pad4(nameLen));
+      }
+    }
+
+    const baseType = propType & 0x0FFF;
+    const isMultiValue = (propType & MV_FLAG) !== 0;
+
+    if (isVarLengthType(baseType)) {
+      // Variable-length types always have a value count (1 for single-value)
+      if (r.remaining < 4) break;
+      const valueCount = r.readUint32LE();
+      let lastValue: Uint8Array | null = null;
+      for (let j = 0; j < valueCount && r.remaining > 0; j++) {
+        lastValue = readMAPIVarValue(r);
+      }
+      if (!isMultiValue && lastValue) {
+        props.set(propID, { type: propType, value: lastValue });
+      }
+    } else if (isMultiValue) {
+      if (r.remaining < 4) break;
+      const valueCount = r.readUint32LE();
+      for (let j = 0; j < valueCount && r.remaining > 0; j++) {
+        readMAPIFixedValue(r, baseType);
+      }
+    } else {
+      const value = readMAPIFixedValue(r, baseType);
+      props.set(propID, { type: propType, value });
+    }
+  }
+
+  return props;
+}
+
+/**
+ * Parse a TNEF (winmail.dat) file and extract the body and attachments.
+ *
+ * @param data - Raw bytes of the TNEF file
+ * @returns Parsed result with body text, HTML body, and attachments
+ */
+export function parseTnef(data: Uint8Array): TnefResult {
+  const result: TnefResult = {
+    body: null,
+    htmlBody: null,
+    attachments: [],
+  };
+
+  debug.group('TNEF Parser');
+  debug.log('Input data size:', data.byteLength, 'bytes');
+
+  if (data.byteLength < 6) {
+    debug.warn('TNEF data too small (< 6 bytes), skipping');
+    debug.groupEnd();
+    return result;
+  }
+
+  const r = new BinaryReader(data);
+
+  const signature = r.readUint32LE();
+  if (signature !== TNEF_SIGNATURE) {
+    debug.warn('Invalid TNEF signature:', '0x' + signature.toString(16).toUpperCase(), '(expected 0x223E9F78)');
+    debug.groupEnd();
+    return result;
+  }
+  debug.log('TNEF signature valid');
+
+  r.skip(2); // legacy key
+
+  // Current attachment being assembled
+  let curAttach: { name: string; mimeType: string; data: Uint8Array | null } | null = null;
+  let attrCount = 0;
+
+  while (r.remaining >= 11) {
+    const level = r.readUint8();
+    const attrID = r.readUint32LE();
+    const attrLen = r.readUint32LE();
+    attrCount++;
+
+    if (attrLen > r.remaining - 2) {
+      debug.warn('Attribute #' + attrCount + ': truncated data — need', attrLen, 'bytes but only', r.remaining - 2, 'available');
+      break;
+    }
+
+    const attrData = r.readBytes(attrLen);
+    r.skip(2); // checksum
+
+    const levelName = level === LVL_MESSAGE ? 'MESSAGE' : level === LVL_ATTACHMENT ? 'ATTACHMENT' : 'UNKNOWN(' + level + ')';
+    debug.log('Attribute #' + attrCount + ':', levelName, 'id=0x' + attrID.toString(16).toUpperCase(), 'len=' + attrLen);
+
+    if (level === LVL_MESSAGE) {
+      if (attrID === attBody) {
+        result.body = new TextDecoder('utf-8').decode(attrData);
+        debug.log('  → Extracted plain text body (' + result.body.length + ' chars)');
+      } else if (attrID === attMAPIProps) {
+        const props = parseMAPIProps(attrData);
+        debug.log('  → Parsed', props.size, 'MAPI properties from message');
+        props.forEach((val, propID) => {
+          debug.log('    MAPI prop 0x' + propID.toString(16).toUpperCase(), 'type=0x' + val.type.toString(16), 'value=' + (val.value instanceof Uint8Array ? val.value.byteLength + ' bytes' : val.value));
+        });
+
+        // HTML body
+        const htmlProp = props.get(PR_BODY_HTML);
+        if (htmlProp?.value instanceof Uint8Array) {
+          const baseType = htmlProp.type & 0x0FFF;
+          if (baseType === PT_STRING8 || baseType === PT_UNICODE) {
+            result.htmlBody = decodeMAPIString(htmlProp.value, baseType);
+          } else {
+            result.htmlBody = new TextDecoder('utf-8').decode(htmlProp.value);
+          }
+          debug.log('  → Extracted HTML body (' + result.htmlBody.length + ' chars)');
+        } else {
+          debug.log('  → No HTML body property (PR_BODY_HTML 0x1013) found in MAPI props');
+        }
+
+        // Plain text body from MAPI props (fallback)
+        if (!result.body) {
+          const bodyProp = props.get(PR_BODY);
+          if (bodyProp?.value instanceof Uint8Array) {
+            result.body = decodeMAPIString(bodyProp.value, bodyProp.type & 0x0FFF);
+            debug.log('  → Extracted plain text body from MAPI props (' + result.body.length + ' chars)');
+          } else {
+            debug.log('  → No plain text body property (PR_BODY 0x1000) found in MAPI props');
+          }
+        }
+      }
+    } else if (level === LVL_ATTACHMENT) {
+      if (attrID === attAttachRenddata) {
+        // Start of a new attachment — flush previous
+        if (curAttach?.data) {
+          debug.log('  → Flushing previous attachment:', curAttach.name, '(' + curAttach.mimeType + ',', curAttach.data.byteLength, 'bytes)');
+          result.attachments.push({
+            name: curAttach.name,
+            mimeType: curAttach.mimeType,
+            data: curAttach.data,
+          });
+        }
+        curAttach = { name: 'attachment', mimeType: 'application/octet-stream', data: null };
+        debug.log('  → New attachment started');
+      } else if (attrID === attAttachTitle && curAttach) {
+        let len = attrData.byteLength;
+        if (len > 0 && attrData[len - 1] === 0) len--;
+        curAttach.name = new TextDecoder('utf-8').decode(attrData.subarray(0, len));
+        debug.log('  → Attachment short name:', curAttach.name);
+      } else if (attrID === attAttachData && curAttach) {
+        curAttach.data = attrData;
+        debug.log('  → Attachment data (attAttachData):', attrData.byteLength, 'bytes');
+      } else if (attrID === attAttachment && curAttach) {
+        const props = parseMAPIProps(attrData);
+        debug.log('  → Parsed', props.size, 'MAPI properties from attachment');
+        props.forEach((val, propID) => {
+          debug.log('    MAPI prop 0x' + propID.toString(16).toUpperCase(), 'type=0x' + val.type.toString(16), 'value=' + (val.value instanceof Uint8Array ? val.value.byteLength + ' bytes' : val.value));
+        });
+
+        const longName = props.get(PR_ATTACH_LONG_FILENAME);
+        if (longName?.value instanceof Uint8Array) {
+          curAttach.name = decodeMAPIString(longName.value, longName.type & 0x0FFF);
+          debug.log('  → Attachment long filename:', curAttach.name);
+        }
+
+        const mimeTag = props.get(PR_ATTACH_MIME_TAG);
+        if (mimeTag?.value instanceof Uint8Array) {
+          curAttach.mimeType = decodeMAPIString(mimeTag.value, mimeTag.type & 0x0FFF);
+          debug.log('  → Attachment MIME type:', curAttach.mimeType);
+        }
+
+        const attachData = props.get(PR_ATTACH_DATA_BIN);
+        if (attachData?.value instanceof Uint8Array) {
+          curAttach.data = attachData.value;
+          debug.log('  → Attachment data (PR_ATTACH_DATA_BIN):', attachData.value.byteLength, 'bytes');
+        } else {
+          debug.log('  → No PR_ATTACH_DATA_BIN found in attachment MAPI props');
+        }
+      }
+    }
+  }
+
+  // Flush last attachment
+  if (curAttach?.data) {
+    debug.log('Flushing final attachment:', curAttach.name, '(' + curAttach.mimeType + ',', curAttach.data.byteLength, 'bytes)');
+    result.attachments.push({
+      name: curAttach.name,
+      mimeType: curAttach.mimeType,
+      data: curAttach.data,
+    });
+  }
+
+  debug.log('TNEF parsing complete — body:', !!result.body, ', htmlBody:', !!result.htmlBody, ', attachments:', result.attachments.length);
+  if (result.attachments.length > 0) {
+    debug.table(result.attachments.map(a => ({ name: a.name, mimeType: a.mimeType, size: a.data.byteLength })));
+  }
+  debug.groupEnd();
+
+  return result;
+}
+
+/**
+ * Check if a MIME attachment is a TNEF (winmail.dat) file.
+ */
+export function isTnefAttachment(name?: string | null, type?: string): boolean {
+  const lowerName = (name || '').toLowerCase();
+  const lowerType = (type || '').toLowerCase();
+  return (
+    lowerName === 'winmail.dat' ||
+    lowerType === 'application/ms-tnef' ||
+    lowerType === 'application/vnd.ms-tnef'
+  );
+}

lib/utils.ts

@@ -27,6 +27,42 @@ export function formatDate(date: Date | string): string {
   });
 }
 
+/**
+ * Format a date/time string respecting the user's 12h/24h time format preference.
+ */
+export function formatDateTime(
+  date: Date | string,
+  timeFormat: '12h' | '24h',
+  options?: {
+    weekday?: 'short' | 'long';
+    year?: 'numeric';
+    month?: 'short' | 'long';
+    day?: 'numeric';
+    second?: '2-digit';
+    timeZoneName?: 'short';
+    dateOnly?: boolean;
+  }
+): string {
+  const d = typeof date === 'string' ? new Date(date) : date;
+  if (isNaN(d.getTime())) return typeof date === 'string' ? date : '';
+
+  const localeOptions: Intl.DateTimeFormatOptions = {};
+  if (options?.weekday) localeOptions.weekday = options.weekday;
+  if (options?.year) localeOptions.year = options.year;
+  if (options?.month) localeOptions.month = options.month;
+  if (options?.day) localeOptions.day = options.day;
+
+  if (!options?.dateOnly) {
+    localeOptions.hour = '2-digit';
+    localeOptions.minute = '2-digit';
+    localeOptions.hour12 = timeFormat === '12h';
+    if (options?.second) localeOptions.second = options.second;
+    if (options?.timeZoneName) localeOptions.timeZoneName = options.timeZoneName;
+  }
+
+  return d.toLocaleString(undefined, localeOptions);
+}
+
 export function truncateText(text: string, maxLength: number): string {
   if (text.length <= maxLength) return text;
   return text.substring(0, maxLength).trim() + "...";
@@ -61,17 +97,19 @@ const ROLE_PRIORITY: Record<string, number> = {
 
 // Deduplicate mailboxes (e.g., "Sent" vs "Sent Mail")
 function deduplicateMailboxes(mailboxes: Mailbox[]): Mailbox[] {
-  const roleMap = new Map<string, Mailbox>();
   const result: Mailbox[] = [];
 
-  // First pass: collect mailboxes with roles
+  // Group role mailboxes by account so deduplication is scoped per-account
+  const rolesByAccount = new Map<string, Mailbox[]>();
   mailboxes.forEach(mb => {
     if (mb.role) {
-      roleMap.set(mb.role, mb);
+      const key = mb.accountId || '';
+      if (!rolesByAccount.has(key)) rolesByAccount.set(key, []);
+      rolesByAccount.get(key)!.push(mb);
     }
   });
 
-  // Second pass: filter out duplicates
+  // Filter out duplicates scoped to the same account
   mailboxes.forEach(mb => {
     // If this mailbox has a role, always keep it
     if (mb.role) {
@@ -79,9 +117,11 @@ function deduplicateMailboxes(mailboxes: Mailbox[]): Mailbox[] {
       return;
     }
 
-    // Check if this is a duplicate of a role-based mailbox
+    // Check if this is a duplicate of a role-based mailbox in the SAME account
+    const accountKey = mb.accountId || '';
+    const accountRoles = rolesByAccount.get(accountKey) || [];
     const lowerName = mb.name.toLowerCase();
-    const isDuplicate = Array.from(roleMap.values()).some(roleMb => {
+    const isDuplicate = accountRoles.some(roleMb => {
       const roleLowerName = roleMb.name.toLowerCase();
       // Check for common duplicates: "Sent Mail" vs "Sent", etc.
       return lowerName.includes(roleLowerName) || roleLowerName.includes(lowerName);

lib/vcard.ts

@@ -1,4 +1,50 @@
-import type { ContactCard, NameComponent, ContactMedia, ContactOnlineService } from "@/lib/jmap/types";
+import type { ContactCard, NameComponent, ContactMedia, ContactOnlineService, AnniversaryDate, PartialDate } from "@/lib/jmap/types";
+
+// Convert RFC 9553 AnniversaryDate (PartialDate|Timestamp|string) to vCard date string
+function anniversaryDateToVcardString(date: AnniversaryDate): string {
+  if (typeof date === 'string') return date;
+  if (date && typeof date === 'object') {
+    if ('@type' in date && date['@type'] === 'Timestamp' && 'utc' in date) {
+      return (date as { utc: string }).utc.split('T')[0];
+    }
+    const pd = date as PartialDate;
+    if (pd.year && pd.month && pd.day) {
+      return `${String(pd.year).padStart(4, '0')}-${String(pd.month).padStart(2, '0')}-${String(pd.day).padStart(2, '0')}`;
+    }
+    if (pd.month && pd.day) {
+      return `--${String(pd.month).padStart(2, '0')}-${String(pd.day).padStart(2, '0')}`;
+    }
+    if (pd.year && pd.month) {
+      return `${String(pd.year).padStart(4, '0')}-${String(pd.month).padStart(2, '0')}`;
+    }
+    if (pd.year) return String(pd.year);
+  }
+  return String(date);
+}
+
+const VCARD_SEX_TO_GENDER: Record<string, string> = {
+  M: "masculine",
+  F: "feminine",
+  O: "other",
+  N: "none",
+  U: "unknown",
+};
+
+const GENDER_TO_VCARD_SEX: Record<string, string> = {
+  masculine: "M",
+  feminine: "F",
+  other: "O",
+  none: "N",
+  unknown: "U",
+};
+
+function vcardSexToGrammaticalGender(sex: string): string {
+  return VCARD_SEX_TO_GENDER[sex.toUpperCase()] || sex.toLowerCase();
+}
+
+function grammaticalGenderToVcardSex(gender: string): string {
+  return GENDER_TO_VCARD_SEX[gender.toLowerCase()] || "";
+}
 
 function unfoldLines(vcf: string): string {
   return vcf.replace(/\r\n[ \t]/g, "").replace(/\r\n/g, "\n").replace(/\r/g, "\n");
@@ -390,9 +436,17 @@ function buildContact(raw: Record<string, string[]>): ContactCard | null {
 
         case "GENDER": {
           const gParts = val.split(";");
-          card.gender = {};
+          const sexCode = gParts[0]?.toUpperCase();
-          if (gParts[0]) card.gender.sex = gParts[0];
+          const identityText = gParts[1];
-          if (gParts[1]) card.gender.identity = gParts[1];
+          if (sexCode || identityText) {
+            card.speakToAs = {};
+            if (sexCode) {
+              card.speakToAs.grammaticalGender = vcardSexToGrammaticalGender(sexCode);
+            }
+            if (identityText) {
+              card.speakToAs.pronouns = { p0: { pronouns: identityText } };
+            }
+          }
           break;
         }
 
@@ -566,14 +620,30 @@ function generateSingleVCard(contact: ContactCard): string {
     for (const addr of Object.values(contact.addresses)) {
       const type = contextToType(addr.contexts);
       const typeParam = type ? `;TYPE=${type}` : "";
+      let street = addr.street || "";
+      let locality = addr.locality || "";
+      let region = addr.region || "";
+      let postcode = addr.postcode || "";
+      let country = addr.country || "";
+      // RFC 9553 components-based address: extract flat fields for vCard ADR
+      if (addr.components && addr.components.length > 0) {
+        const findComp = (kind: string) => addr.components!.filter(c => c.kind === kind).map(c => c.value).join(' ');
+        const number = findComp('number');
+        const name = findComp('name');
+        street = street || [number, name].filter(Boolean).join(' ');
+        locality = locality || findComp('locality');
+        region = region || findComp('region');
+        postcode = postcode || findComp('postcode');
+        country = country || findComp('country');
+      }
       const parts = [
         "",
         "",
-        addr.street || "",
+        street,
-        addr.locality || "",
+        locality,
-        addr.region || "",
+        region,
-        addr.postcode || "",
+        postcode,
-        addr.country || "",
+        country,
       ];
       lines.push(`ADR${typeParam}:${parts.map(encodeValue).join(";")}`);
     }
@@ -581,12 +651,13 @@ function generateSingleVCard(contact: ContactCard): string {
 
   if (contact.anniversaries) {
     for (const ann of Object.values(contact.anniversaries)) {
+      const dateStr = anniversaryDateToVcardString(ann.date);
       if (ann.kind === "birth") {
-        lines.push(`BDAY:${ann.date}`);
+        lines.push(`BDAY:${dateStr}`);
       } else if (ann.kind === "wedding") {
-        lines.push(`ANNIVERSARY:${ann.date}`);
+        lines.push(`ANNIVERSARY:${dateStr}`);
       } else if (ann.kind === "death") {
-        lines.push(`DEATHDATE:${ann.date}`);
+        lines.push(`DEATHDATE:${dateStr}`);
       }
     }
   }
@@ -684,10 +755,15 @@ function generateSingleVCard(contact: ContactCard): string {
     }
   }
 
-  if (contact.gender) {
+  if (contact.speakToAs) {
-    const sex = contact.gender.sex || "";
+    const sex = contact.speakToAs.grammaticalGender
-    const identity = contact.gender.identity || "";
+      ? grammaticalGenderToVcardSex(contact.speakToAs.grammaticalGender)
-    lines.push(`GENDER:${sex}${identity ? `;${identity}` : ""}`);
+      : "";
+    const pronouns = contact.speakToAs.pronouns;
+    const identity = pronouns ? Object.values(pronouns)[0]?.pronouns || "" : "";
+    if (sex || identity) {
+      lines.push(`GENDER:${sex}${identity ? `;${identity}` : ""}`);
+    }
   }
 
   if (contact.calendarUri) {