chore: update version to 1.5.4

Adds a once-per-day heartbeat that lets the project see how many
instances run Bulwark, on what platforms, with what features enabled,
and roughly how many accounts they have. No email addresses, hostnames,
IPs, or any end-user data are ever sent.

- lib/telemetry: state file, payload builder, jittered scheduler,
  instance_id persistence at <data-dir>/.telemetry-id (delete to reset)
- app/api/admin/telemetry: admin API for status / set-consent /
  set-endpoint / send-now (all audit-logged)
- app/admin/telemetry: settings page with status, JSON payload preview,
  endpoint editor, send-now button, link to the privacy page
- instrumentation.node.ts: starts the scheduler on boot

Default state is enabled. The first heartbeat fires 1 hour after boot
so an admin who installs and immediately disables produces zero pings.
Disable via the settings UI, BULWARK_TELEMETRY=off (or
BULWARK_TELEMETRY_DISABLED=1), or by clearing the endpoint.

Account counts are bucketed (1, 2-5, 6-10, 11-50, 51-200, 201+) so a
small instance can't be re-identified by exact size. The /.telemetry-id
file can be deleted to mint a fresh instance_id.

Receiving collector is open source at bulwarkmail/dashboard. Self-host
your own and point at it via BULWARK_TELEMETRY_URL. Full schema,
retention (90d raw → aggregates), and lawful basis are documented at
bulwarkmail.org/docs/legal/privacy/telemetry.

.env.example

@@ -71,11 +71,36 @@ JMAP_SERVER_URL=https://your-jmap-server.com
 
 # Directory for storing encrypted settings files (default: ./data/settings).
 # For Docker, the working directory is /app, so the default resolves to
-# /app/data/settings - mount a persistent volume there:
-#   volumes:
-#     - bulwark-settings:/app/data/settings
+# /app/data/settings - mount a persistent volume there (see docker-compose.yml).
 # SETTINGS_DATA_DIR=./data/settings
 
+# =============================================================================
+# Admin Dashboard Data
+# =============================================================================
+
+# Directory for admin dashboard state: config overrides, admin password hash,
+# installed plugins/themes, and audit logs (default: ./data/admin).
+# For Docker, the default resolves to /app/data/admin - mount a persistent
+# volume there (see docker-compose.yml).
+# ADMIN_DATA_DIR=./data/admin
+
+# =============================================================================
+# Anonymous Telemetry
+# =============================================================================
+
+# Anonymous instance telemetry is enabled by default. Heartbeats contain no PII:
+# version, platform, bucketed account counts, and feature toggles only. See
+# https://bulwarkmail.org/docs/legal/privacy/telemetry for the full schema.
+#
+# Disable telemetry entirely (overrides the admin UI):
+# BULWARK_TELEMETRY=off
+
+# Directory for telemetry state: instance id, consent, login HMACs
+# (default: ./data/telemetry). For Docker, the default resolves to
+# /app/data/telemetry - mount a persistent volume there (see docker-compose.yml)
+# so the instance id and consent choice survive upgrades.
+# TELEMETRY_DATA_DIR=./data/telemetry
+
 # =============================================================================
 # Server Listen Address
 # =============================================================================
@@ -183,7 +208,8 @@ LOGIN_WEBSITE_URL=https://bulwarkmail.org
 # =============================================================================
 
 # URL of the BulwarkMail extension directory for the admin marketplace.
-# Set this to enable browsing and installing plugins/themes from the directory.
+# Defaults to https://extensions.bulwarkmail.org. Override only if you run
+# your own directory (e.g. http://localhost:3001 for local development).
 # EXTENSION_DIRECTORY_URL=https://extensions.bulwarkmail.org
 
 # =============================================================================

CHANGELOG.md

@@ -1,5 +1,69 @@
 # Changelog
 
+## 1.5.4 (2026-05-01)
+
+### Features
+
+- **PWA**: Web push notifications for new inbox mail (#233), with click-through to open the message
+- **Composer**: Insert and edit tables in rich-text emails (#236)
+- **Mail**: Configurable sub-addressing delimiter character (#239)
+- **i18n**: Turkish localization
+- **i18n**: Missing keys filled in across 15 locales
+
+### Fixes
+
+- **Mail**: Set In-Reply-To and References headers on replies (#234)
+- **Mail**: Persist htmlBody in drafts to preserve rich formatting (#236)
+- **Auth**: Pin JMAP auth verification to the configured server URL (#237)
+- **Auth**: Evict unrecoverable basic-auth accounts on reload
+- **Notifications**: Scope new-mail notifications to genuine inbox deliveries
+- **Notifications**: Extend PushVerification timeout and clean up leftover subscriptions
+- **Viewer**: Smooth out body load to prevent flicker on first render
+- **Viewer**: Prevent iframe flash when loading images or trusting the sender
+- **Viewer**: Pad bare HTML emails like plain-text mails for consistent layout
+- **Viewer**: Light-mode override now only affects body content
+- **Viewer**: Detect `<style>` tag when applying padding
+- **Viewer**: Drop iframe border-radius
+- **Calendar**: Localize event start date in detail popover and event modal
+- **Dev**: Include http protocol in connect-src for development mode CSP
+
+## 1.5.3 (2026-04-28)
+
+> **New:** Help shape Bulwark Webmail. Each instance now sends a lightweight daily heartbeat (version, platform, bucketed account counts, feature toggles - never message data or PII) so we can see which platforms and features actually get used and prioritize fixes where they matter most. You're in control: opt out any time from **Admin → Telemetry** or by setting `BULWARK_TELEMETRY=off`. Full schema in the [privacy notice](https://bulwarkmail.org/docs/legal/privacy/telemetry).
+
+### Features
+
+- **Telemetry**: Anonymous instance telemetry, on by default. Reports schema version, platform, bucketed account counts, and feature toggles only - disable from the admin UI, with `BULWARK_TELEMETRY=off`, or by clearing the endpoint
+- **Telemetry**: Track unique logins (HMAC'd per instance, 90-day retention) so the heartbeat can report bucketed account totals without storing usernames
+- **Plugins**: Theme API v2 with token compiler and skin slot
+- **Plugins**: Extension preview page and detailed extension info API
+- **Calendar**: Right-click context menu on empty calendar space
+- **Docker**: Persistent named volume for telemetry data so the instance id and admin's consent choice survive container upgrades
+
+### Fixes
+
+- **Security**: Block telemetry endpoint from pointing at internal/loopback hosts (validation + DNS-rebind re-check at fetch time)
+- **Security**: Harden plugin config, TOTP token exchange, and branding file serving
+- **Mail**: Batch shortcuts now act on the multi-selection when one is present (#228)
+
+## 1.5.2 (2026-04-27)
+
+### Features
+
+- **Plugins**: New `composer-sidebar` slot and `ui:composer-sidebar` permission - plugins can now render a panel on either side of the New Message dialog. See `repos/subway-surfers` for an example
+- **Plugins**: Manifests can declare `frameOrigins` - a strictly-validated list of `https://host` origins the plugin needs to embed. The proxy reads the union from enabled plugins and merges it into the host CSP `frame-src`, so the host CSP no longer needs to know about specific embed providers
+- **Calendar/Contacts**: JMAP sharing for calendars and address books
+- **i18n**: Czech language support
+
+### Fixes
+
+- **Security**: Validate URLs before outbound fetch
+- **Calendar**: Prevent drag creation on touch events in the time grid
+- **Contacts**: Emit RFC 9553 name kinds and decode QUOTED-PRINTABLE in vCard import (#224, #187)
+- **Mail**: Hide preview line in compact density to match settings preview (#223)
+- **Proxy**: Inline matcher for Next.js proxy and drop unnecessary Node.js runtime config
+- **i18n**: Portuguese fixes for "ficheiro" and "contactos" variants
+
 ## 1.5.1 (2026-04-25)
 
 ### Features

Dockerfile

@@ -26,7 +26,7 @@ RUN apk upgrade --no-cache && \
 COPY --from=builder /app/public ./public
 COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
 COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static
-RUN mkdir -p /app/data/settings /app/data/admin && chown -R nextjs:nodejs /app/data
+RUN mkdir -p /app/data/settings /app/data/admin /app/data/telemetry && chown -R nextjs:nodejs /app/data
 USER nextjs
 EXPOSE 3000
 ENV PORT=3000

FEATURES.md

@@ -94,7 +94,7 @@
 
 ## Internationalization
 
-14 languages: English · Français · 日本語 · Español · Italiano · Deutsch · Nederlands · Português · Русский · 한국어 · Polski · Latviešu · 简体中文 · Українська
+15 languages: English · Français · 日本語 · Español · Italiano · Deutsch · Nederlands · Português · Русский · Türkçe · 한국어 · Polski · Latviešu · 简体中文 · Українська
 
 Automatic browser detection with persistent preference. Configurable locale URL prefix via `NEXT_PUBLIC_LOCALE_PREFIX`.
 

README.md

@@ -12,7 +12,7 @@ A modern, self-hosted webmail client for [Stalwart Mail Server](https://stalw.ar
 
 [![License: AGPL v3](https://img.shields.io/badge/license-AGPL%20v3-blue.svg?logo=gnu&logoColor=white)](LICENSE)
 [![Discord](https://img.shields.io/discord/1482128142939455674?color=7289da&label=discord&logo=discord&logoColor=white)](https://discord.gg/tYCujymGrT)
-[![Version](https://img.shields.io/badge/version-1.5.1-green.svg?logo=git&logoColor=white)](CHANGELOG.md)
+[![Version](https://img.shields.io/badge/version-1.5.4-green.svg?logo=git&logoColor=white)](CHANGELOG.md)
 [![Docker](https://img.shields.io/badge/docker-ghcr.io%2Fbulwarkmail%2Fwebmail-blue?logo=docker&logoColor=white)](https://ghcr.io/bulwarkmail/webmail)
 
 </div>
@@ -53,6 +53,8 @@ A modern, self-hosted webmail client for [Stalwart Mail Server](https://stalw.ar
 </tr>
 </table>
 
+> **Anonymous telemetry is on by default** since 1.5.3. Each instance sends a daily heartbeat (version, platform, bucketed account counts, feature toggles - no message data, no PII). Disable from **Admin → Telemetry**, by setting `BULWARK_TELEMETRY=off`, or by clearing the endpoint. Full schema: [privacy notice](https://bulwarkmail.org/docs/legal/privacy/telemetry).
+
 ## Overview
 
 Bulwark is a full webmail suite – not just an inbox. It bundles the four apps most self-hosters end up wanting on the same login:
@@ -62,7 +64,7 @@ Bulwark is a full webmail suite – not just an inbox. It bundles the four apps
 - **Contacts** – multiple address books, groups, vCard import/export
 - **Files** – Stalwart's JMAP FileNode storage with previews and folder upload
 
-Plus the infrastructure around them: OAuth2 / OIDC SSO, TOTP 2FA, multi-account (up to 5 at once), 14 languages, PWA install, dark/light themes, a plugin system with an extension marketplace, and a admin dashboard.
+Plus the infrastructure around them: OAuth2 / OIDC SSO, TOTP 2FA, multi-account (up to 5 at once), 15 languages, PWA install, dark/light themes, a plugin system with an extension marketplace, and a admin dashboard.
 
 Full feature list: **[FEATURES.md](FEATURES.md)**.
 

VERSION

@@ -1 +1 @@
-1.5.1
+1.5.4

app/[locale]/calendar/page.tsx

@@ -31,6 +31,7 @@ import { CalendarSidebarPanel } from "@/components/calendar/calendar-sidebar-pan
 import { EventModal, type PendingEventPreview } from "@/components/calendar/event-modal";
 import { EventDetailPopover } from "@/components/calendar/event-detail-popover";
 import { EventContextMenu } from "@/components/calendar/event-context-menu";
+import { EmptySpaceContextMenu } from "@/components/calendar/empty-space-context-menu";
 import { useContextMenu } from "@/hooks/use-context-menu";
 import { useRefreshGesture } from "@/hooks/use-refresh-gesture";
 import { downloadEventICS } from "@/lib/calendar-ics-export";
@@ -47,7 +48,11 @@ import { getEventStartDate } from "@/lib/calendar-utils";
 import { useTaskStore } from "@/stores/task-store";
 import { useContactStore } from "@/stores/contact-store";
 import { cn } from "@/lib/utils";
-import type { CalendarEvent, CalendarParticipant } from "@/lib/jmap/types";
+import type { Calendar, CalendarEvent, CalendarParticipant, CalendarRights } from "@/lib/jmap/types";
+import { ShareCollectionDialog } from "@/components/settings/share-collection-dialog";
+import { ConfirmDialog } from "@/components/ui/confirm-dialog";
+import { useConfirmDialog } from "@/hooks/use-confirm-dialog";
+import { CreateCalendarModal } from "@/components/calendar/create-calendar-modal";
 import { getUserParticipantId } from "@/lib/calendar-participants";
 import { generateBirthdayEvents, createBirthdayCalendar, BIRTHDAY_CALENDAR_ID } from "@/lib/birthday-calendar";
 import { debug } from "@/lib/debug";
@@ -72,7 +77,8 @@ export default function CalendarPage() {
     calendars, events, selectedDate, viewMode, selectedCalendarIds,
     isLoading, isLoadingEvents, supportsCalendar, error,
     fetchCalendars, fetchEvents, createEvent, updateEvent, deleteEvent, rsvpEvent,
-    setSelectedDate, setViewMode, toggleCalendarVisibility, updateCalendar,
+    setSelectedDate, setViewMode, toggleCalendarVisibility, updateCalendar, shareCalendar,
+    removeCalendar, clearCalendarEvents,
     refreshAllSubscriptions, icalSubscriptions,
   } = useCalendarStore();
   const { firstDayOfWeek, timeFormat, showWeekNumbers, enableCalendarTasks, showTasksOnCalendar, calendarHoverPreview, showBirthdayCalendar, birthdayCalendarColor, updateSetting } = useSettingsStore();
@@ -91,9 +97,15 @@ export default function CalendarPage() {
   const [showImportModal, setShowImportModal] = useState(false);
   const [showSubscriptionModal, setShowSubscriptionModal] = useState(false);
   const [editingSubscription, setEditingSubscription] = useState<string | null>(null);
+  const [sharingCalendarId, setSharingCalendarId] = useState<string | null>(null);
+  const [defaultCalendarIdForCreate, setDefaultCalendarIdForCreate] = useState<string | undefined>(undefined);
+  const [showCreateCalendar, setShowCreateCalendar] = useState(false);
+  const { dialogProps: confirmDialogProps, confirm: confirmAction } = useConfirmDialog();
+  const tMgmt = useTranslations("calendar.management");
   const [editEvent, setEditEvent] = useState<CalendarEvent | null>(null);
   const [defaultModalDate, setDefaultModalDate] = useState<Date | undefined>();
   const [defaultModalEndDate, setDefaultModalEndDate] = useState<Date | undefined>();
+  const [defaultModalAllDay, setDefaultModalAllDay] = useState(false);
   const [miniMonth, setMiniMonth] = useState(new Date());
   const [pendingScopeAction, setPendingScopeAction] = useState<PendingScopeAction | null>(null);
   const [detailEvent, setDetailEvent] = useState<CalendarEvent | null>(null);
@@ -316,11 +328,12 @@ export default function CalendarPage() {
     setSelectedDate(date);
   }, [setSelectedDate]);
 
-  const openCreateModal = useCallback((date?: Date, endDate?: Date) => {
+  const openCreateModal = useCallback((date?: Date, endDate?: Date, allDay?: boolean) => {
     setEditEvent(null);
     const d = date || selectedDate;
     setDefaultModalDate(d);
     setDefaultModalEndDate(endDate);
+    setDefaultModalAllDay(allDay ?? false);
     setSelectedDate(d);
     setShowEventModal(true);
   }, [selectedDate, setSelectedDate]);
@@ -385,6 +398,21 @@ export default function CalendarPage() {
     openEventContextMenu(e, event);
   }, [closeDetail, openEventContextMenu]);
 
+  const {
+    contextMenu: emptyContextMenu,
+    openContextMenu: openEmptyContextMenu,
+    closeContextMenu: closeEmptyContextMenu,
+    menuRef: emptyContextMenuRef,
+  } = useContextMenu<{ date: Date; hour?: number; allDayArea?: boolean }>();
+
+  const handleContextMenuEmpty = useCallback(
+    (e: React.MouseEvent, date: Date, hour?: number, allDayArea?: boolean) => {
+      closeDetail();
+      openEmptyContextMenu(e, { date, hour, allDayArea });
+    },
+    [closeDetail, openEmptyContextMenu],
+  );
+
   const handleHoverEvent = useCallback((event: CalendarEvent, anchorRect: DOMRect) => {
     if (isMobile) return;
     if (calendarHoverPreview === 'off') return;
@@ -951,6 +979,7 @@ export default function CalendarPage() {
               onHoverEvent={handleHoverEvent}
               onHoverLeave={handleHoverLeave}
               onContextMenuEvent={handleContextMenuEvent}
+              onContextMenuEmpty={handleContextMenuEmpty}
               onCreateAtTime={openCreateModal}
               firstDayOfWeek={firstDayOfWeek}
               isMobile={isMobile}
@@ -968,6 +997,7 @@ export default function CalendarPage() {
               onHoverEvent={handleHoverEvent}
               onHoverLeave={handleHoverLeave}
               onContextMenuEvent={handleContextMenuEvent}
+              onContextMenuEmpty={handleContextMenuEmpty}
               onCreateAtTime={openCreateModal}
               firstDayOfWeek={firstDayOfWeek}
               timeFormat={timeFormat}
@@ -987,6 +1017,7 @@ export default function CalendarPage() {
               onHoverEvent={handleHoverEvent}
               onHoverLeave={handleHoverLeave}
               onContextMenuEvent={handleContextMenuEvent}
+              onContextMenuEmpty={handleContextMenuEmpty}
               onCreateAtTime={openCreateModal}
               timeFormat={timeFormat}
               isMobile={isMobile}
@@ -1102,6 +1133,42 @@ export default function CalendarPage() {
                 }
                 updateCalendar(client, calendarId, { color });
               } : undefined}
+              onShareCalendar={client ? (cal) => setSharingCalendarId(cal.id) : undefined}
+              onCreateEvent={(cal: Calendar) => {
+                setDefaultCalendarIdForCreate(cal.id);
+                openCreateModal();
+              }}
+              onClearCalendar={client ? async (cal: Calendar) => {
+                const ok = await confirmAction({
+                  title: tMgmt("clear_events"),
+                  message: tMgmt("confirm_clear", { name: cal.name }),
+                  variant: "destructive",
+                  confirmText: tMgmt("clear_events"),
+                });
+                if (!ok) return;
+                try {
+                  const count = await clearCalendarEvents(client, cal.id);
+                  toast.success(tMgmt("events_cleared", { count }));
+                } catch {
+                  toast.error(tMgmt("error_clear"));
+                }
+              } : undefined}
+              onDeleteCalendar={client ? async (cal: Calendar) => {
+                const ok = await confirmAction({
+                  title: tMgmt("delete"),
+                  message: tMgmt("confirm_delete", { name: cal.name }),
+                  variant: "destructive",
+                  confirmText: tMgmt("delete"),
+                });
+                if (!ok) return;
+                try {
+                  await removeCalendar(client, cal.id);
+                  toast.success(tMgmt("calendar_deleted"));
+                } catch {
+                  toast.error(tMgmt("error_delete"));
+                }
+              } : undefined}
+              onCreateCalendar={client ? () => setShowCreateCalendar(true) : undefined}
               onSubscribe={() => setShowSubscriptionModal(true)}
               onEditSubscription={(subId) => setEditingSubscription(subId)}
               client={client}
@@ -1165,11 +1232,13 @@ export default function CalendarPage() {
                 calendars={calendars}
                 defaultDate={defaultModalDate}
                 defaultEndDate={defaultModalEndDate}
+                defaultAllDay={defaultModalAllDay}
+                defaultCalendarId={defaultCalendarIdForCreate}
                 onSave={handleSaveEvent}
                 onDelete={handleDeleteEvent}
                 onDuplicate={handleDuplicateEvent}
                 onRsvp={handleRsvp}
-                onClose={() => { setShowEventModal(false); setEditEvent(null); setPendingPreview(null); }}
+                onClose={() => { setShowEventModal(false); setEditEvent(null); setPendingPreview(null); setDefaultCalendarIdForCreate(undefined); setDefaultModalAllDay(false); }}
                 onPreviewChange={setPendingPreview}
                 currentUserEmails={currentUserEmails}
                 isMobile={false}
@@ -1235,6 +1304,38 @@ export default function CalendarPage() {
         />
       )}
 
+      {emptyContextMenu.data && (() => {
+        const { date, hour } = emptyContextMenu.data;
+        return (
+          <EmptySpaceContextMenu
+            position={emptyContextMenu.position}
+            isOpen={emptyContextMenu.isOpen}
+            onClose={closeEmptyContextMenu}
+            menuRef={emptyContextMenuRef}
+            onNewEvent={() => {
+              const d = new Date(date);
+              if (typeof hour === "number") {
+                d.setHours(hour, 0, 0, 0);
+              } else {
+                const now = new Date();
+                d.setHours(now.getHours() + 1, 0, 0, 0);
+              }
+              openCreateModal(d);
+            }}
+            onNewAllDayEvent={() => {
+              const d = new Date(date);
+              d.setHours(0, 0, 0, 0);
+              openCreateModal(d, undefined, true);
+            }}
+            onNewTask={enableCalendarTasks ? () => {
+              setEditTask(null);
+              setShowTaskModal(true);
+            } : undefined}
+            onGoToToday={goToToday}
+          />
+        );
+      })()}
+
       {detailEvent && detailAnchorRect && (
         <EventDetailPopover
           event={detailEvent}
@@ -1261,11 +1362,13 @@ export default function CalendarPage() {
           calendars={calendars}
           defaultDate={defaultModalDate}
           defaultEndDate={defaultModalEndDate}
+          defaultAllDay={defaultModalAllDay}
+          defaultCalendarId={defaultCalendarIdForCreate}
           onSave={handleSaveEvent}
           onDelete={handleDeleteEvent}
           onDuplicate={handleDuplicateEvent}
           onRsvp={handleRsvp}
-          onClose={() => { setShowEventModal(false); setEditEvent(null); }}
+          onClose={() => { setShowEventModal(false); setEditEvent(null); setDefaultCalendarIdForCreate(undefined); setDefaultModalAllDay(false); }}
           currentUserEmails={currentUserEmails}
           isMobile={true}
         />
@@ -1305,6 +1408,33 @@ export default function CalendarPage() {
         onSelect={handleScopeSelect}
         onClose={() => setPendingScopeAction(null)}
       />
+
+      <ConfirmDialog {...confirmDialogProps} />
+
+      {showCreateCalendar && client && (
+        <CreateCalendarModal
+          client={client}
+          onClose={() => setShowCreateCalendar(false)}
+        />
+      )}
+
+      {sharingCalendarId && client && (() => {
+        const cal = allCalendars.find((c) => c.id === sharingCalendarId);
+        if (!cal) return null;
+        return (
+          <ShareCollectionDialog
+            client={client}
+            kind="calendar"
+            collectionName={cal.name}
+            shareWith={cal.shareWith}
+            ownAccountId={client.getAccountId()}
+            onShare={async (principalId, rights) => {
+              await shareCalendar(client, cal.id, principalId, rights as CalendarRights | null);
+            }}
+            onClose={() => setSharingCalendarId(null)}
+          />
+        );
+      })()}
     </div>
   );
 }

app/[locale]/contacts/page.tsx

@@ -27,7 +27,8 @@ import { useSidebarApps } from "@/hooks/use-sidebar-apps";
 import { ResizeHandle } from "@/components/layout/resize-handle";
 import { useIsMobile } from "@/hooks/use-media-query";
 import { useRefreshGesture } from "@/hooks/use-refresh-gesture";
-import type { ContactCard, AddressBook } from "@/lib/jmap/types";
+import type { ContactCard, AddressBook, AddressBookRights } from "@/lib/jmap/types";
+import { ShareCollectionDialog } from "@/components/settings/share-collection-dialog";
 
 type View =
   | "list"
@@ -75,6 +76,8 @@ export default function ContactsPage() {
     bulkAddToGroup,
     moveContactToAddressBook,
     renameAddressBook,
+    removeAddressBook,
+    shareAddressBook,
     renameKeyword,
     importContacts,
   } = useContactStore();
@@ -83,6 +86,8 @@ export default function ContactsPage() {
   const [activeCategory, setActiveCategory] = useState<ContactCategory>("all");
   const [showImportDialog, setShowImportDialog] = useState(false);
   const [renamingAddressBook, setRenamingAddressBook] = useState<AddressBook | null>(null);
+  const [sharingAddressBookId, setSharingAddressBookId] = useState<string | null>(null);
+  const [defaultBookIdForCreate, setDefaultBookIdForCreate] = useState<string | undefined>(undefined);
   const [renamingKeyword, setRenamingKeyword] = useState<string | null>(null);
   const [selectedGroupId, setSelectedGroupId] = useState<string | null>(null);
   const hasFetched = useRef(false);
@@ -329,6 +334,7 @@ export default function ContactsPage() {
       addLocalContact(localContact);
       toast.success(t("toast.created"));
     }
+    setDefaultBookIdForCreate(undefined);
     setView("list");
   }, [supportsSync, client, createContact, addLocalContact, t]);
 
@@ -346,6 +352,7 @@ export default function ContactsPage() {
   }, [supportsSync, client, selectedContact, updateContact, updateLocalContact, t]);
 
   const handleCancel = () => {
+    setDefaultBookIdForCreate(undefined);
     if (view === "group-create" || view === "group-edit") {
       setView(selectedGroup ? "group-detail" : "list");
     } else if (view === "bulk-add-to-group") {
@@ -517,7 +524,7 @@ export default function ContactsPage() {
   const renderRightPanel = () => {
     switch (view) {
       case "create":
-        return <ContactForm addressBooks={addressBooks} allKeywords={allKeywords} onSave={handleSaveNew} onCancel={handleCancel} />;
+        return <ContactForm addressBooks={addressBooks} allKeywords={allKeywords} defaultAddressBookId={defaultBookIdForCreate} onSave={handleSaveNew} onCancel={handleCancel} />;
 
       case "edit":
         if (!selectedContact) return null;
@@ -690,6 +697,26 @@ export default function ContactsPage() {
                       onDropContacts={handleDropContacts}
                       onDropContactsToCategory={handleDropContactsToCategory}
                       onRenameAddressBook={client ? (book) => setRenamingAddressBook(book) : undefined}
+                      onShareAddressBook={client ? (book) => setSharingAddressBookId(book.id) : undefined}
+                      onCreateContactInBook={(book) => {
+                        setDefaultBookIdForCreate(book.id);
+                        handleCreateNew();
+                      }}
+                      onDeleteAddressBook={client ? async (book) => {
+                        const ok = await confirmDialog({
+                          title: t("address_books.delete"),
+                          message: t("address_books.confirm_delete", { name: book.name }),
+                          variant: "destructive",
+                          confirmText: t("address_books.delete"),
+                        });
+                        if (!ok) return;
+                        try {
+                          await removeAddressBook(client, book);
+                          toast.success(t("address_books.deleted"));
+                        } catch {
+                          toast.error(t("address_books.delete_failed"));
+                        }
+                      } : undefined}
                       onRenameKeyword={(kw) => setRenamingKeyword(kw)}
                     />
                   </div>
@@ -838,6 +865,23 @@ export default function ContactsPage() {
           </div>
         </div>
       )}
+      {sharingAddressBookId && client && (() => {
+        const book = addressBooks.find((b) => b.id === sharingAddressBookId);
+        if (!book) return null;
+        return (
+          <ShareCollectionDialog
+            client={client}
+            kind="addressBook"
+            collectionName={book.name}
+            shareWith={book.shareWith}
+            ownAccountId={client.getAccountId()}
+            onShare={async (principalId, rights) => {
+              await shareAddressBook(client, book, principalId, rights as AddressBookRights | null);
+            }}
+            onClose={() => setSharingAddressBookId(null)}
+          />
+        );
+      })()}
     </div>
   );
 }

app/[locale]/page.tsx

@@ -51,6 +51,7 @@ 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 { computeReplyThreadingHeaders } from "@/lib/email-threading";
 import { Search, Filter, ChevronDown, X, Paperclip, Star, Mail, MailOpen, RotateCcw, PenSquare, PenLine, CheckSquare, Square, AlertTriangle } from "lucide-react";
 import { ResizeHandle } from "@/components/layout/resize-handle";
 import { Button } from "@/components/ui/button";
@@ -171,6 +172,11 @@ export default function Home() {
     createMailbox,
     renameMailbox,
     deleteMailbox,
+    batchDelete,
+    batchArchive,
+    batchMarkAsRead,
+    batchMarkAsSpam,
+    batchUndoSpam,
   } = useEmailStore();
 
   const enableUnifiedMailbox = useSettingsStore((s) => s.enableUnifiedMailbox);
@@ -353,27 +359,77 @@ export default function Home() {
     onToggleStar: () => {
       if (selectedEmail) handleToggleStar();
     },
-    onArchive: () => {
-      if (selectedEmail) handleArchive();
+    onArchive: async () => {
+      if (selectedEmailIds.size > 0 && client) {
+        try {
+          await batchArchive(client);
+        } catch (error) {
+          console.error("Failed to batch archive:", error);
+        }
+      } else if (selectedEmail) {
+        handleArchive();
+      }
     },
-    onDelete: () => {
-      if (selectedEmail) handleDelete();
+    onDelete: async () => {
+      if (selectedEmailIds.size > 0 && client) {
+        const currentMailbox = mailboxes.find(m => m.id === selectedMailbox);
+        const isInTrash = currentMailbox?.role === 'trash';
+        const isInJunk = currentMailbox?.role === 'junk';
+        const permanentlyDeleteJunk = useSettingsStore.getState().permanentlyDeleteJunk;
+        const permanent = isInTrash || (isInJunk && permanentlyDeleteJunk);
+        const confirmed = await confirmDialog({
+          title: permanent
+            ? t('email_list.permanent_delete_confirm_title')
+            : t('email_list.batch_actions.delete_confirm_title'),
+          message: permanent
+            ? t('email_list.permanent_delete_confirm_batch_message', { count: selectedEmailIds.size })
+            : t('email_list.batch_actions.delete_confirm_message', { count: selectedEmailIds.size }),
+          confirmText: permanent
+            ? t('email_list.permanent_delete')
+            : t('email_list.batch_actions.delete'),
+          variant: "destructive",
+        });
+        if (!confirmed) return;
+        try {
+          await batchDelete(client, permanent);
+        } catch (error) {
+          console.error("Failed to batch delete:", error);
+        }
+      } else if (selectedEmail) {
+        handleDelete();
+      }
     },
     onMarkAsUnread: async () => {
-      if (selectedEmail && client) {
+      if (!client) return;
+      if (selectedEmailIds.size > 0) {
+        await batchMarkAsRead(client, false);
+      } else if (selectedEmail) {
         await markAsRead(client, selectedEmail.id, false);
       }
     },
     onMarkAsRead: async () => {
-      if (selectedEmail && client) {
+      if (!client) return;
+      if (selectedEmailIds.size > 0) {
+        await batchMarkAsRead(client, true);
+      } else if (selectedEmail) {
         await markAsRead(client, selectedEmail.id, true);
       }
     },
-    onToggleSpam: () => {
-      if (selectedEmail) {
-        // Check if we're in junk folder
-        const currentMailbox = mailboxes.find(m => m.id === selectedMailbox);
-        const isInJunk = currentMailbox?.role === 'junk';
+    onToggleSpam: async () => {
+      const currentMailbox = mailboxes.find(m => m.id === selectedMailbox);
+      const isInJunk = currentMailbox?.role === 'junk';
+      if (selectedEmailIds.size > 0 && client) {
+        const ids = Array.from(selectedEmailIds);
+        try {
+          if (isInJunk) {
+            await batchUndoSpam(client, ids);
+          } else {
+            await batchMarkAsSpam(client, ids);
+          }
+        } catch (error) {
+          console.error("Failed to batch toggle spam:", error);
+        }
+      } else if (selectedEmail) {
         if (isInJunk) {
           handleUndoSpam();
         } else {
@@ -408,13 +464,14 @@ export default function Home() {
       clearSelection();
     },
   // eslint-disable-next-line react-hooks/exhaustive-deps
-  }), [emails, selectedEmail, client, selectedMailbox, isMobile, isTablet]);
+  }), [emails, selectedEmail, client, selectedMailbox, isMobile, isTablet, selectedEmailIds, mailboxes]);
 
   // Initialize keyboard shortcuts
   useKeyboardShortcuts({
     enabled: isAuthenticated && !showComposer,
     emails,
     selectedEmailId: selectedEmail?.id,
+    selectionCount: selectedEmailIds.size,
     handlers: keyboardHandlers,
   });
 
@@ -595,11 +652,50 @@ export default function Home() {
     });
   }, [enableUnifiedMailbox, isAuthenticated, client, mailboxes, connectedAccountsSignature, buildUnifiedAccounts, populateUnifiedAccountMailboxes, refreshUnifiedCounts]);
 
+  // System-notification click handler. The push SW navigates the user back
+  // here with `?email=<id>` (specific email it built the toast from) or
+  // `?openLatestUnread=1` (generic "New mail" toast — happens when the
+  // preview API failed). We resolve those params once after the inbox has
+  // finished loading and open the right message, then strip the params so a
+  // refresh doesn't re-open it.
+  const notificationParamHandledRef = useRef(false);
+  useEffect(() => {
+    if (notificationParamHandledRef.current) return;
+    if (!isAuthenticated || !client) return;
+    if (mailboxes.length === 0) return;
+
+    const params = new URLSearchParams(window.location.search);
+    const emailIdParam = params.get('email');
+    const openLatestUnread = params.get('openLatestUnread') === '1';
+    if (!emailIdParam && !openLatestUnread) return;
+
+    // For the latest-unread case we need the inbox emails loaded; bail and
+    // let the effect re-run once `emails` is populated.
+    if (openLatestUnread && emails.length === 0) return;
+
+    notificationParamHandledRef.current = true;
+    window.history.replaceState({}, '', window.location.pathname);
+
+    if (emailIdParam) {
+      setLoadingEmail(true);
+      fetchEmailContent(client, emailIdParam).finally(() => setLoadingEmail(false));
+      return;
+    }
+
+    // emails are sorted receivedAt-desc, so the first unread is the newest.
+    const newestUnread = emails.find(e => !e.keywords?.$seen);
+    if (newestUnread) {
+      selectEmail(newestUnread);
+    }
+  }, [isAuthenticated, client, mailboxes.length, emails, fetchEmailContent, selectEmail, setLoadingEmail]);
+
   // Auto-fetch full email content when an email is auto-selected (e.g. after delete/archive)
   useEffect(() => {
     if (!selectedEmail || !client) return;
-    // If the email lacks bodyValues, it was auto-selected from the list and needs full content
-    if (!selectedEmail.bodyValues) {
+    // If the email lacks bodyValues, it was auto-selected from the list and needs full content.
+    // Skip when handleEmailSelect already started a fetch (it sets isLoadingEmail before
+    // calling selectEmail on the stub), to avoid a duplicate request.
+    if (!selectedEmail.bodyValues && !isLoadingEmail) {
       const perAccountClient = isUnifiedView && selectedEmail.accountId
         ? useAuthStore.getState().getClientForAccount(selectedEmail.accountId)
         : undefined;
@@ -694,6 +790,8 @@ export default function Home() {
     fromName?: string;
     identityId?: string;
     attachments?: Array<{ blobId: string; name: string; type: string; size: number; disposition?: 'attachment' | 'inline'; cid?: string }>;
+    inReplyTo?: string[];
+    references?: string[];
   }) => {
     if (!client) return;
 
@@ -701,7 +799,7 @@ export default function Home() {
       const effectiveMode = pendingDraft?.mode ?? composerMode;
       const originalEmailId = selectedEmail?.id;
 
-      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);
+      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, data.inReplyTo, data.references);
       setShowComposer(false);
 
       // Mark the original email with $answered or $forwarded keyword
@@ -1393,6 +1491,12 @@ export default function Home() {
 
     const originalEmailId = selectedEmail.id;
 
+    // RFC 5322 §3.6.4 threading — keep the conversation stitched together (#234).
+    const threading = computeReplyThreadingHeaders({
+      messageId: selectedEmail.messageId,
+      references: selectedEmail.references,
+    });
+
     // Send reply with just the body text
     await sendEmail(
       client,
@@ -1404,7 +1508,11 @@ export default function Home() {
       primaryIdentity?.id,
       primaryIdentity?.email,
       undefined,
-      primaryIdentity?.name || undefined
+      primaryIdentity?.name || undefined,
+      undefined,
+      undefined,
+      threading?.inReplyTo,
+      threading?.references,
     );
 
     // Mark the original email as answered
@@ -1446,7 +1554,13 @@ export default function Home() {
       setShowComposer(false);
     }
 
-    // Set loading state immediately (keep current email visible)
+    // Show the list stub immediately so subject/sender render without
+    // waiting for the body fetch — avoids the loading flicker.
+    const listEmail = emails.find(e => e.id === email.id);
+    if (listEmail) {
+      selectEmail(listEmail);
+    }
+
     setLoadingEmail(true);
 
     // On mobile, switch to viewer
@@ -1463,7 +1577,6 @@ export default function Home() {
     try {
       // In unified view each email carries its own accountId. Use that
       // account's client so we fetch from the server that actually owns it.
-      const listEmail = emails.find(e => e.id === email.id);
       const emailAccountId = isUnifiedView ? listEmail?.accountId : undefined;
       const perAccountClient = emailAccountId
         ? useAuthStore.getState().getClientForAccount(emailAccountId)
@@ -2055,6 +2168,9 @@ export default function Home() {
                     htmlBody: selectedEmail.bodyValues?.[selectedEmail.htmlBody?.[0]?.partId || '']?.value || undefined,
                     receivedAt: selectedEmail.receivedAt,
                     attachments: selectedEmail.attachments,
+                    messageId: selectedEmail.messageId,
+                    inReplyTo: selectedEmail.inReplyTo,
+                    references: selectedEmail.references,
                   } : undefined)}
                   initialDraftText={composerDraftText}
                   initialData={pendingDraft}

app/admin/layout.tsx

@@ -14,6 +14,7 @@ import {
   KeyRound,
   Puzzle,
   SwatchBook,
+  Activity,
   Mail,
   Calendar,
   BookUser,
@@ -56,6 +57,7 @@ const NAV_GROUPS = [
   {
     label: 'System',
     items: [
+      { href: '/admin/telemetry', label: 'Telemetry', icon: Activity },
       { href: '/admin/logs', label: 'Audit Log', icon: ScrollText },
     ],
   },

app/admin/marketplace/[slug]/page.tsx

@@ -0,0 +1,542 @@
+'use client';
+
+import { useEffect, useState, useCallback } from 'react';
+import { useParams } from 'next/navigation';
+import Link from 'next/link';
+import {
+  ArrowLeft,
+  Download,
+  Loader2,
+  Puzzle,
+  SwatchBook,
+  Star,
+  Trash2,
+  Check,
+  Settings as SettingsIcon,
+  ExternalLink,
+  Shield,
+  AlertTriangle,
+  FileCode,
+  ChevronDown,
+  ChevronUp,
+} from 'lucide-react';
+import { apiFetch } from '@/lib/browser-navigation';
+
+interface PreviewData {
+  extension: {
+    slug: string;
+    name: string;
+    type: 'plugin' | 'theme';
+    pluginType: string | null;
+    description: string;
+    longDescription: string | null;
+    tags: string[];
+    permissions: string[];
+    totalDownloads: number;
+    featured: boolean;
+    githubRepo: string | null;
+    license: string | null;
+    minAppVersion: string | null;
+    author: {
+      displayName: string;
+      githubLogin: string;
+      avatarUrl: string | null;
+      verified?: boolean;
+    } | null;
+    latestVersion: string | null;
+    versions: Array<{
+      version: string;
+      changelog: string | null;
+      bundleSize: number;
+      minAppVersion: string | null;
+      publishedAt: string | null;
+      permissions: string[];
+    }>;
+    screenshots: Array<{ url: string; altText: string | null }>;
+    themePreviews: Array<{
+      variant: 'light' | 'dark';
+      previewPath: string;
+      colors: Record<string, string> | null;
+    }>;
+    createdAt: string | null;
+    updatedAt: string | null;
+  };
+  bundle: {
+    manifest: Record<string, unknown> | null;
+    source: { name: string; content: string; truncated: boolean } | null;
+    size: number;
+    error: string | null;
+  };
+  installed: boolean;
+}
+
+const RISKY_PERMISSIONS = new Set([
+  'mail:write',
+  'mail:delete',
+  'storage:write',
+  'network',
+  'admin',
+]);
+
+export default function MarketplacePreviewPage() {
+  const params = useParams();
+  const slug = params.slug as string;
+
+  const [data, setData] = useState<PreviewData | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
+  const [installing, setInstalling] = useState(false);
+  const [uninstalling, setUninstalling] = useState(false);
+  const [message, setMessage] = useState<{ type: 'success' | 'error'; text: string } | null>(null);
+  const [showSource, setShowSource] = useState(false);
+  const [showManifest, setShowManifest] = useState(false);
+
+  const fetchPreview = useCallback(async () => {
+    setLoading(true);
+    setError(null);
+    try {
+      const res = await apiFetch(`/api/admin/marketplace/${encodeURIComponent(slug)}`);
+      if (!res.ok) {
+        const body = await res.json().catch(() => ({}));
+        setError(body.error || 'Failed to load preview');
+        return;
+      }
+      setData(await res.json());
+    } catch {
+      setError('Failed to connect to extension directory');
+    } finally {
+      setLoading(false);
+    }
+  }, [slug]);
+
+  useEffect(() => { fetchPreview(); }, [fetchPreview]);
+
+  async function handleInstall() {
+    if (!data) return;
+    setInstalling(true);
+    setMessage(null);
+    try {
+      const res = await apiFetch('/api/admin/marketplace', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({
+          slug: data.extension.slug,
+          version: data.extension.latestVersion || '1.0.0',
+          type: data.extension.type,
+        }),
+      });
+      const body = await res.json();
+      if (res.ok) {
+        const warnings = body.warnings?.length ? ` (${body.warnings.length} warning(s))` : '';
+        setMessage({ type: 'success', text: `"${data.extension.name}" installed${warnings}` });
+        setData(prev => prev ? { ...prev, installed: true } : prev);
+      } else {
+        setMessage({ type: 'error', text: body.error || 'Installation failed' });
+      }
+    } catch {
+      setMessage({ type: 'error', text: 'Installation failed - network error' });
+    } finally {
+      setInstalling(false);
+    }
+  }
+
+  async function handleUninstall() {
+    if (!data) return;
+    if (!confirm(`Remove "${data.extension.name}"? This cannot be undone.`)) return;
+
+    setUninstalling(true);
+    setMessage(null);
+    try {
+      const endpoint = data.extension.type === 'theme'
+        ? '/api/admin/themes'
+        : '/api/admin/plugins';
+      const res = await apiFetch(endpoint, {
+        method: 'DELETE',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ id: data.extension.slug }),
+      });
+      const body = await res.json().catch(() => ({}));
+      if (res.ok) {
+        setMessage({ type: 'success', text: `"${data.extension.name}" removed` });
+        setData(prev => prev ? { ...prev, installed: false } : prev);
+      } else {
+        setMessage({ type: 'error', text: body.error || 'Uninstall failed' });
+      }
+    } catch {
+      setMessage({ type: 'error', text: 'Uninstall failed - network error' });
+    } finally {
+      setUninstalling(false);
+    }
+  }
+
+  if (loading) {
+    return (
+      <div className="flex items-center justify-center py-12 text-muted-foreground text-sm">
+        <Loader2 className="w-4 h-4 animate-spin mr-2" />
+        Loading...
+      </div>
+    );
+  }
+
+  if (error || !data) {
+    return (
+      <div className="space-y-4">
+        <Link
+          href="/admin/marketplace"
+          className="inline-flex items-center gap-1.5 text-sm text-muted-foreground hover:text-foreground"
+        >
+          <ArrowLeft className="w-4 h-4" /> Back to Marketplace
+        </Link>
+        <p className="text-sm text-destructive">{error || 'Extension not found'}</p>
+      </div>
+    );
+  }
+
+  const ext = data.extension;
+  const bundle = data.bundle;
+  const isPlugin = ext.type === 'plugin';
+  const manifestPerms = (bundle.manifest?.permissions as string[] | undefined) || ext.permissions || [];
+  const frameOrigins = (bundle.manifest?.frameOrigins as string[] | undefined) || [];
+  const settingsSchema = bundle.manifest?.settingsSchema as Record<string, { type: string; label: string; description?: string; default?: unknown }> | undefined;
+
+  return (
+    <div className="space-y-6 max-w-4xl">
+      {/* Back link */}
+      <Link
+        href="/admin/marketplace"
+        className="inline-flex items-center gap-1.5 text-sm text-muted-foreground hover:text-foreground"
+      >
+        <ArrowLeft className="w-4 h-4" /> Back to Marketplace
+      </Link>
+
+      {/* Header */}
+      <div className="flex items-start gap-4">
+        <div className="w-14 h-14 rounded-lg bg-muted flex items-center justify-center shrink-0">
+          {isPlugin ? (
+            <Puzzle className="w-7 h-7 text-muted-foreground" />
+          ) : (
+            <SwatchBook className="w-7 h-7 text-muted-foreground" />
+          )}
+        </div>
+        <div className="flex-1 min-w-0">
+          <div className="flex items-center gap-2">
+            <h1 className="text-2xl font-semibold text-foreground truncate">{ext.name}</h1>
+            {ext.featured && <Star className="w-4 h-4 text-warning fill-warning shrink-0" />}
+            {data.installed && (
+              <span className="inline-flex items-center gap-1 text-xs px-2 py-0.5 rounded-md bg-emerald-100 text-emerald-700 dark:bg-emerald-950/30 dark:text-emerald-400 font-medium">
+                <Check className="w-3 h-3" /> Installed
+              </span>
+            )}
+          </div>
+          <div className="flex items-center gap-2 mt-1 text-sm text-muted-foreground flex-wrap">
+            <span className={`text-[10px] px-1.5 py-0.5 rounded font-medium ${
+              isPlugin
+                ? 'bg-blue-100 text-blue-700 dark:bg-blue-950/30 dark:text-blue-400'
+                : 'bg-purple-100 text-purple-700 dark:bg-purple-950/30 dark:text-purple-400'
+            }`}>
+              {isPlugin ? (ext.pluginType || 'plugin') : 'theme'}
+            </span>
+            {ext.author && (
+              <span>by {ext.author.displayName}</span>
+            )}
+            {ext.latestVersion && <span>v{ext.latestVersion}</span>}
+            {ext.license && <span>{ext.license}</span>}
+            <span className="inline-flex items-center gap-1">
+              <Download className="w-3 h-3" />
+              {ext.totalDownloads.toLocaleString()}
+            </span>
+          </div>
+        </div>
+
+        {/* Action buttons */}
+        <div className="flex items-center gap-2 shrink-0">
+          {data.installed ? (
+            <>
+              <Link
+                href={isPlugin ? `/admin/plugins/${ext.slug}` : '/admin/themes'}
+                className="inline-flex items-center gap-1.5 h-9 px-3 rounded-md border border-border text-sm font-medium text-foreground hover:bg-muted transition-colors"
+              >
+                <SettingsIcon className="w-4 h-4" />
+                Manage
+              </Link>
+              <button
+                onClick={handleUninstall}
+                disabled={uninstalling}
+                className="inline-flex items-center gap-1.5 h-9 px-3 rounded-md bg-destructive text-destructive-foreground text-sm font-medium hover:bg-destructive/90 disabled:opacity-50 transition-colors"
+              >
+                {uninstalling ? <Loader2 className="w-4 h-4 animate-spin" /> : <Trash2 className="w-4 h-4" />}
+                Uninstall
+              </button>
+            </>
+          ) : (
+            <button
+              onClick={handleInstall}
+              disabled={installing || !!bundle.error}
+              className="inline-flex items-center gap-1.5 h-9 px-4 rounded-md bg-primary text-primary-foreground text-sm font-medium hover:bg-primary/90 disabled:opacity-50 transition-colors"
+            >
+              {installing ? <Loader2 className="w-4 h-4 animate-spin" /> : <Download className="w-4 h-4" />}
+              Install
+            </button>
+          )}
+        </div>
+      </div>
+
+      {message && (
+        <div className={`text-sm rounded-md px-3 py-2 ${message.type === 'success' ? 'bg-emerald-50 text-emerald-700 dark:bg-emerald-950/30 dark:text-emerald-300' : 'bg-destructive/10 text-destructive'}`}>
+          {message.text}
+        </div>
+      )}
+
+      {bundle.error && (
+        <div className="flex items-start gap-2 text-sm rounded-md px-3 py-2 bg-amber-50 text-amber-800 dark:bg-amber-950/30 dark:text-amber-300">
+          <AlertTriangle className="w-4 h-4 shrink-0 mt-0.5" />
+          <div>
+            <p className="font-medium">Could not preview bundle</p>
+            <p className="text-xs mt-0.5 opacity-90">{bundle.error}</p>
+          </div>
+        </div>
+      )}
+
+      {/* Description */}
+      <section className="border border-border rounded-lg p-4">
+        <h2 className="text-sm font-medium text-foreground">About</h2>
+        <p className="text-sm text-muted-foreground mt-2">{ext.description}</p>
+        {ext.longDescription && ext.longDescription !== ext.description && (
+          <p className="text-sm text-muted-foreground mt-3 whitespace-pre-wrap">{ext.longDescription}</p>
+        )}
+        {ext.tags.length > 0 && (
+          <div className="flex flex-wrap gap-1 mt-3">
+            {ext.tags.map(tag => (
+              <span key={tag} className="text-[10px] px-1.5 py-0.5 rounded bg-muted text-muted-foreground">
+                {tag}
+              </span>
+            ))}
+          </div>
+        )}
+        <div className="flex items-center gap-3 text-xs text-muted-foreground mt-4 pt-3 border-t border-border flex-wrap">
+          {ext.minAppVersion && <span>Requires app v{ext.minAppVersion}+</span>}
+          {bundle.size > 0 && <span>Bundle: {(bundle.size / 1024).toFixed(1)} KB</span>}
+          {ext.githubRepo && (
+            <a
+              href={`https://github.com/${ext.githubRepo}`}
+              target="_blank"
+              rel="noopener noreferrer"
+              className="inline-flex items-center gap-1 hover:text-foreground"
+            >
+              <ExternalLink className="w-3 h-3" />
+              {ext.githubRepo}
+            </a>
+          )}
+        </div>
+      </section>
+
+      {/* Screenshots */}
+      {ext.screenshots.length > 0 && (
+        <section className="border border-border rounded-lg p-4">
+          <h2 className="text-sm font-medium text-foreground">Screenshots</h2>
+          <div className="grid grid-cols-1 sm:grid-cols-2 gap-3 mt-3">
+            {ext.screenshots.map((s, i) => (
+              <img
+                key={i}
+                src={s.url}
+                alt={s.altText || `Screenshot ${i + 1}`}
+                className="w-full rounded-md border border-border bg-muted"
+                loading="lazy"
+              />
+            ))}
+          </div>
+        </section>
+      )}
+
+      {/* Theme color preview */}
+      {!isPlugin && ext.themePreviews.length > 0 && (
+        <section className="border border-border rounded-lg p-4">
+          <h2 className="text-sm font-medium text-foreground">Theme preview</h2>
+          <div className="grid grid-cols-1 sm:grid-cols-2 gap-3 mt-3">
+            {ext.themePreviews.map(preview => (
+              <ThemeColorSwatch key={preview.variant} preview={preview} />
+            ))}
+          </div>
+        </section>
+      )}
+
+      {/* Permissions */}
+      {isPlugin && (
+        <section className="border border-border rounded-lg p-4">
+          <div className="flex items-center gap-2">
+            <Shield className="w-4 h-4 text-muted-foreground" />
+            <h2 className="text-sm font-medium text-foreground">Permissions</h2>
+          </div>
+          {manifestPerms.length === 0 ? (
+            <p className="text-sm text-muted-foreground mt-2">This plugin requests no permissions.</p>
+          ) : (
+            <ul className="mt-3 space-y-1.5">
+              {manifestPerms.map(perm => {
+                const risky = RISKY_PERMISSIONS.has(perm);
+                return (
+                  <li
+                    key={perm}
+                    className={`flex items-center gap-2 text-sm rounded-md px-2 py-1 ${
+                      risky
+                        ? 'bg-amber-50 text-amber-800 dark:bg-amber-950/30 dark:text-amber-300'
+                        : 'bg-muted/50 text-foreground'
+                    }`}
+                  >
+                    {risky && <AlertTriangle className="w-3.5 h-3.5 shrink-0" />}
+                    <code className="font-mono text-xs">{perm}</code>
+                  </li>
+                );
+              })}
+            </ul>
+          )}
+          {frameOrigins.length > 0 && (
+            <div className="mt-4 pt-3 border-t border-border">
+              <h3 className="text-xs font-medium text-foreground">Iframe origins</h3>
+              <p className="text-xs text-muted-foreground mt-0.5">
+                The plugin will be allowed to embed content from these origins.
+              </p>
+              <ul className="mt-2 space-y-1">
+                {frameOrigins.map(origin => (
+                  <li key={origin} className="text-xs font-mono text-foreground bg-muted/50 px-2 py-1 rounded">
+                    {origin}
+                  </li>
+                ))}
+              </ul>
+            </div>
+          )}
+        </section>
+      )}
+
+      {/* Settings schema preview */}
+      {isPlugin && settingsSchema && Object.keys(settingsSchema).length > 0 && (
+        <section className="border border-border rounded-lg p-4">
+          <h2 className="text-sm font-medium text-foreground">User settings</h2>
+          <p className="text-xs text-muted-foreground mt-0.5">Settings users will be able to configure after install.</p>
+          <ul className="mt-3 divide-y divide-border">
+            {Object.entries(settingsSchema).map(([key, field]) => (
+              <li key={key} className="py-2">
+                <div className="flex items-center gap-2">
+                  <code className="text-xs font-mono text-foreground">{key}</code>
+                  <span className="text-[10px] px-1.5 py-0.5 rounded bg-muted text-muted-foreground">{field.type}</span>
+                </div>
+                <div className="text-sm text-foreground mt-0.5">{field.label}</div>
+                {field.description && (
+                  <div className="text-xs text-muted-foreground mt-0.5">{field.description}</div>
+                )}
+              </li>
+            ))}
+          </ul>
+        </section>
+      )}
+
+      {/* Source / manifest disclosure */}
+      {bundle.manifest && (
+        <section className="border border-border rounded-lg">
+          <button
+            onClick={() => setShowManifest(v => !v)}
+            className="w-full flex items-center justify-between gap-2 px-4 py-3 text-left hover:bg-muted/30 transition-colors"
+          >
+            <div className="flex items-center gap-2">
+              <FileCode className="w-4 h-4 text-muted-foreground" />
+              <h2 className="text-sm font-medium text-foreground">manifest.json</h2>
+            </div>
+            {showManifest ? <ChevronUp className="w-4 h-4 text-muted-foreground" /> : <ChevronDown className="w-4 h-4 text-muted-foreground" />}
+          </button>
+          {showManifest && (
+            <pre className="px-4 pb-4 text-xs font-mono overflow-x-auto text-foreground whitespace-pre">
+              {JSON.stringify(bundle.manifest, null, 2)}
+            </pre>
+          )}
+        </section>
+      )}
+
+      {bundle.source && (
+        <section className="border border-border rounded-lg">
+          <button
+            onClick={() => setShowSource(v => !v)}
+            className="w-full flex items-center justify-between gap-2 px-4 py-3 text-left hover:bg-muted/30 transition-colors"
+          >
+            <div className="flex items-center gap-2">
+              <FileCode className="w-4 h-4 text-muted-foreground" />
+              <h2 className="text-sm font-medium text-foreground">{bundle.source.name}</h2>
+              {bundle.source.truncated && (
+                <span className="text-[10px] px-1.5 py-0.5 rounded bg-amber-100 text-amber-700 dark:bg-amber-950/30 dark:text-amber-400">truncated</span>
+              )}
+            </div>
+            {showSource ? <ChevronUp className="w-4 h-4 text-muted-foreground" /> : <ChevronDown className="w-4 h-4 text-muted-foreground" />}
+          </button>
+          {showSource && (
+            <pre className="px-4 pb-4 text-xs font-mono overflow-x-auto text-foreground whitespace-pre max-h-[600px] overflow-y-auto">
+              {bundle.source.content}
+            </pre>
+          )}
+        </section>
+      )}
+
+      {/* Version history */}
+      {ext.versions.length > 0 && (
+        <section className="border border-border rounded-lg p-4">
+          <h2 className="text-sm font-medium text-foreground">Version history</h2>
+          <ul className="mt-3 divide-y divide-border">
+            {ext.versions.slice(0, 5).map(v => (
+              <li key={v.version} className="py-2 flex items-start justify-between gap-3">
+                <div className="min-w-0 flex-1">
+                  <div className="flex items-center gap-2">
+                    <code className="text-xs font-mono text-foreground">v{v.version}</code>
+                    {v.publishedAt && (
+                      <span className="text-xs text-muted-foreground">
+                        {new Date(v.publishedAt).toLocaleDateString()}
+                      </span>
+                    )}
+                  </div>
+                  {v.changelog && (
+                    <p className="text-xs text-muted-foreground mt-0.5 whitespace-pre-wrap">{v.changelog}</p>
+                  )}
+                </div>
+                <span className="text-xs text-muted-foreground shrink-0">
+                  {(v.bundleSize / 1024).toFixed(1)} KB
+                </span>
+              </li>
+            ))}
+          </ul>
+        </section>
+      )}
+    </div>
+  );
+}
+
+function ThemeColorSwatch({ preview }: { preview: { variant: 'light' | 'dark'; colors: Record<string, string> | null } }) {
+  const colors = preview.colors || {};
+  const bg = colors.background || (preview.variant === 'dark' ? '#0f0f10' : '#ffffff');
+  const fg = colors.foreground || (preview.variant === 'dark' ? '#fafafa' : '#0a0a0a');
+  const accent = colors.primary || colors.accent || '#7c5cff';
+  const muted = colors.muted || (preview.variant === 'dark' ? '#1a1a1c' : '#f5f5f5');
+  const border = colors.border || (preview.variant === 'dark' ? '#27272a' : '#e5e5e5');
+
+  return (
+    <div className="rounded-md border border-border overflow-hidden">
+      <div className="px-3 py-2 text-xs font-medium text-muted-foreground bg-muted/30 border-b border-border capitalize">
+        {preview.variant}
+      </div>
+      <div className="p-3 space-y-2" style={{ background: bg, color: fg }}>
+        <div className="flex items-center gap-2">
+          <span className="inline-block w-6 h-6 rounded" style={{ background: accent }} />
+          <span className="text-sm font-medium" style={{ color: fg }}>Sample text</span>
+        </div>
+        <div className="rounded p-2 text-xs" style={{ background: muted, border: `1px solid ${border}` }}>
+          <span style={{ color: fg }}>Card surface</span>
+        </div>
+        <div className="flex flex-wrap gap-1">
+          {Object.entries(colors).slice(0, 6).map(([key, value]) => (
+            <span
+              key={key}
+              title={`${key}: ${value}`}
+              className="inline-block w-4 h-4 rounded border"
+              style={{ background: value, borderColor: border }}
+            />
+          ))}
+        </div>
+      </div>
+    </div>
+  );
+}

app/admin/marketplace/page.tsx

@@ -1,7 +1,8 @@
 'use client';
 
 import { useEffect, useState, useCallback } from 'react';
-import { Search, Download, Check, Loader2, Store, Puzzle, SwatchBook, Star, Filter } from 'lucide-react';
+import Link from 'next/link';
+import { Search, Download, Check, Loader2, Store, Puzzle, SwatchBook, Star, Eye } from 'lucide-react';
 import { apiFetch } from '@/lib/browser-navigation';
 
 interface Extension {
@@ -262,10 +263,11 @@ function ExtensionCard({
   onInstall: () => void;
 }) {
   const isPlugin = extension.type === 'plugin';
+  const previewHref = `/admin/marketplace/${encodeURIComponent(extension.slug)}`;
 
   return (
-    <div className="border border-border rounded-lg overflow-hidden hover:border-ring/30 transition-colors">
-      <div className="p-4">
+    <div className="group relative border border-border rounded-lg overflow-hidden hover:border-ring/30 transition-colors">
+      <Link href={previewHref} className="block p-4 focus:outline-none focus-visible:ring-2 focus-visible:ring-ring/40 rounded-lg">
         {/* Header */}
         <div className="flex items-start gap-3">
           <div className="w-10 h-10 rounded-md bg-muted flex items-center justify-center shrink-0">
@@ -277,7 +279,9 @@ function ExtensionCard({
           </div>
           <div className="min-w-0 flex-1">
             <div className="flex items-center gap-1.5">
-              <span className="text-sm font-medium text-foreground truncate">{extension.name}</span>
+              <span className="text-sm font-medium text-foreground truncate group-hover:underline">
+                {extension.name}
+              </span>
               {extension.featured && (
                 <Star className="w-3.5 h-3.5 text-warning shrink-0 fill-warning" />
               )}
@@ -315,7 +319,7 @@ function ExtensionCard({
           </div>
         )}
 
-        {/* Footer */}
+        {/* Footer (download count + permissions) */}
         <div className="flex items-center justify-between mt-4 pt-3 border-t border-border">
           <div className="flex items-center gap-3 text-xs text-muted-foreground">
             <span className="flex items-center gap-1">
@@ -328,27 +332,34 @@ function ExtensionCard({
               </span>
             )}
           </div>
-
-          {extension.installed ? (
-            <span className="inline-flex items-center gap-1 h-7 px-2.5 rounded-md bg-emerald-100 text-emerald-700 dark:bg-emerald-950/30 dark:text-emerald-400 text-xs font-medium">
-              <Check className="w-3 h-3" />
-              Installed
-            </span>
-          ) : (
-            <button
-              onClick={onInstall}
-              disabled={installing}
-              className="inline-flex items-center gap-1.5 h-7 px-3 rounded-md bg-primary text-primary-foreground text-xs font-medium hover:bg-primary/90 disabled:opacity-50 transition-colors"
-            >
-              {installing ? (
-                <Loader2 className="w-3 h-3 animate-spin" />
-              ) : (
-                <Download className="w-3 h-3" />
-              )}
-              Install
-            </button>
-          )}
+          <span className="inline-flex items-center gap-1 text-xs text-muted-foreground group-hover:text-foreground">
+            <Eye className="w-3 h-3" />
+            Preview
+          </span>
         </div>
+      </Link>
+
+      {/* Quick install button (sits over the link, stops navigation) */}
+      <div className="px-4 pb-4 -mt-1">
+        {extension.installed ? (
+          <span className="inline-flex items-center gap-1 h-7 px-2.5 rounded-md bg-emerald-100 text-emerald-700 dark:bg-emerald-950/30 dark:text-emerald-400 text-xs font-medium">
+            <Check className="w-3 h-3" />
+            Installed
+          </span>
+        ) : (
+          <button
+            onClick={(e) => { e.preventDefault(); e.stopPropagation(); onInstall(); }}
+            disabled={installing}
+            className="inline-flex items-center gap-1.5 h-7 px-3 rounded-md bg-primary text-primary-foreground text-xs font-medium hover:bg-primary/90 disabled:opacity-50 transition-colors"
+          >
+            {installing ? (
+              <Loader2 className="w-3 h-3 animate-spin" />
+            ) : (
+              <Download className="w-3 h-3" />
+            )}
+            Quick install
+          </button>
+        )}
       </div>
     </div>
   );

app/admin/page.tsx

@@ -31,6 +31,7 @@ export default function AdminDashboardPage() {
   const [pluginCount, setPluginCount] = useState(0);
   const [themeCount, setThemeCount] = useState(0);
   const [policyRuleCount, setPolicyRuleCount] = useState(0);
+  const [accountCounts, setAccountCounts] = useState<{ total: number; active7d: number } | null>(null);
   const [jmapHealth, setJmapHealth] = useState<'unknown' | 'ok' | 'error'>('unknown');
 
   useEffect(() => {
@@ -38,7 +39,7 @@ export default function AdminDashboardPage() {
   }, []);
 
   async function fetchDashboardData() {
-    const [statusRes, auditRes, configRes, adminConfigRes, pluginRes, themeRes, policyRes] = await Promise.all([
+    const [statusRes, auditRes, configRes, adminConfigRes, pluginRes, themeRes, policyRes, telemetryRes] = await Promise.all([
       apiFetch('/api/admin/auth'),
       apiFetch('/api/admin/audit?limit=10'),
       apiFetch('/api/config'),
@@ -46,6 +47,7 @@ export default function AdminDashboardPage() {
       apiFetch('/api/admin/plugins').catch(() => null),
       apiFetch('/api/admin/themes').catch(() => null),
       apiFetch('/api/admin/policy').catch(() => null),
+      apiFetch('/api/admin/telemetry').catch(() => null),
     ]);
 
     if (statusRes.ok) setStatus(await statusRes.json());
@@ -73,6 +75,12 @@ export default function AdminDashboardPage() {
       const disabledGates = policy.features ? Object.values(policy.features).filter((v: unknown) => !v).length : 0;
       setPolicyRuleCount(restrictionCount + disabledGates);
     }
+    if (telemetryRes?.ok) {
+      const telemetry = await telemetryRes.json();
+      if (telemetry.accountCounts && typeof telemetry.accountCounts.total === 'number') {
+        setAccountCounts(telemetry.accountCounts);
+      }
+    }
 
     if (configData?.jmapServerUrl) {
       try {
@@ -165,6 +173,16 @@ export default function AdminDashboardPage() {
         </SettingItem>
       </SettingsSection>
 
+      {/* Accounts */}
+      <SettingsSection title="Accounts" description="Unique logins recorded over the last 90 days">
+        <SettingItem label="Total accounts" description="Distinct identities seen in the retention window">
+          <span className="text-sm text-foreground">{accountCounts?.total ?? '-'}</span>
+        </SettingItem>
+        <SettingItem label="Active in last 7 days" description="Identities with a login in the past week">
+          <span className="text-sm text-foreground">{accountCounts?.active7d ?? '-'}</span>
+        </SettingItem>
+      </SettingsSection>
+
       {/* Extensions */}
       <SettingsSection title="Extensions" description="Installed plugins, themes, and policy rules">
         <SettingItem label="Plugins">

app/admin/policy/page.tsx

@@ -15,6 +15,7 @@ const FEATURE_GATE_LABELS: Partial<Record<keyof FeatureGates, { label: string; d
   customKeywordsEnabled: { label: 'Custom Keywords', description: 'Allow user-created labels and tags' },
   templatesEnabled: { label: 'Email Templates', description: 'Allow email template creation and library' },
   calendarTasksEnabled: { label: 'Calendar Tasks', description: 'Show task panel in calendar view' },
+  contactsEnabled: { label: 'Contacts', description: 'Enable contacts/address book features' },
   smimeEnabled: { label: 'S/MIME', description: 'Enable certificate management and email signing' },
   externalContentEnabled: { label: 'External Content', description: 'Allow users to choose external content loading policy' },
   debugModeEnabled: { label: 'Debug Mode', description: 'Allow users to enable debug/diagnostic mode' },

app/admin/telemetry/page.tsx

@@ -0,0 +1,250 @@
+'use client';
+
+import { useEffect, useState } from 'react';
+import { Loader2, Send, Save, CheckCircle2, XCircle, ExternalLink } from 'lucide-react';
+import { apiFetch } from '@/lib/browser-navigation';
+
+interface TelemetryStatus {
+  consent: 'pending' | 'on' | 'off';
+  consentSource: 'env' | 'file';
+  endpoint: string;
+  defaultEndpoint: string;
+  consentedAt: string | null;
+  lastSentAt: string | null;
+  nextScheduledAt: string | null;
+  payloadPreview: Record<string, unknown>;
+  accountCounts: { total: number; active7d: number };
+}
+
+function timeAgo(iso: string | null): string {
+  if (!iso) return 'never';
+  const d = Date.now() - new Date(iso).getTime();
+  if (d < 0) return new Date(iso).toLocaleString();
+  const m = Math.floor(d / 60000);
+  if (m < 1) return 'just now';
+  if (m < 60) return `${m} min ago`;
+  const h = Math.floor(m / 60);
+  if (h < 48) return `${h} hours ago`;
+  const days = Math.floor(h / 24);
+  return `${days} days ago`;
+}
+
+export default function AdminTelemetryPage() {
+  const [status, setStatus] = useState<TelemetryStatus | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [busy, setBusy] = useState<string | null>(null);
+  const [endpointDraft, setEndpointDraft] = useState('');
+  const [sendResult, setSendResult] = useState<{ ok: boolean; msg: string } | null>(null);
+
+  async function refresh(): Promise<void> {
+    setLoading(true);
+    try {
+      const r = await apiFetch('/api/admin/telemetry');
+      if (!r.ok) throw new Error('failed to load');
+      const data = (await r.json()) as TelemetryStatus;
+      setStatus(data);
+      setEndpointDraft(data.endpoint);
+    } catch (err) {
+      console.error(err);
+    } finally {
+      setLoading(false);
+    }
+  }
+  useEffect(() => { void refresh(); }, []);
+
+  async function setConsent(consent: 'on' | 'off'): Promise<void> {
+    setBusy('consent');
+    try {
+      const r = await apiFetch('/api/admin/telemetry', {
+        method: 'POST',
+        headers: { 'content-type': 'application/json' },
+        body: JSON.stringify({ action: 'set-consent', consent }),
+      });
+      if (!r.ok) {
+        const j = (await r.json().catch(() => ({}))) as { error?: string };
+        alert(j.error ?? 'failed');
+      }
+      await refresh();
+    } finally { setBusy(null); }
+  }
+
+  async function saveEndpoint(): Promise<void> {
+    setBusy('endpoint');
+    try {
+      const r = await apiFetch('/api/admin/telemetry', {
+        method: 'POST',
+        headers: { 'content-type': 'application/json' },
+        body: JSON.stringify({ action: 'set-endpoint', endpoint: endpointDraft }),
+      });
+      if (!r.ok) {
+        const j = (await r.json().catch(() => ({}))) as { error?: string };
+        alert(j.error ?? 'failed');
+      }
+      await refresh();
+    } finally { setBusy(null); }
+  }
+
+  async function sendNow(): Promise<void> {
+    setBusy('send');
+    setSendResult(null);
+    try {
+      const r = await apiFetch('/api/admin/telemetry', {
+        method: 'POST',
+        headers: { 'content-type': 'application/json' },
+        body: JSON.stringify({ action: 'send-now' }),
+      });
+      const j = (await r.json().catch(() => ({}))) as { ok?: boolean; status?: number; error?: string };
+      setSendResult({
+        ok: !!j.ok,
+        msg: j.ok ? `sent (HTTP ${j.status ?? '?'})` : `failed: ${j.error ?? 'unknown'}`,
+      });
+      await refresh();
+    } finally { setBusy(null); }
+  }
+
+  if (loading || !status) {
+    return (
+      <div className="p-8 flex items-center gap-2 text-muted-foreground">
+        <Loader2 className="h-4 w-4 animate-spin" /> loading…
+      </div>
+    );
+  }
+
+  const envOverridden = status.consentSource === 'env';
+  const isOn = status.consent === 'on';
+
+  return (
+    <div className="max-w-3xl mx-auto p-6 space-y-6">
+      <header className="space-y-2">
+        <h1 className="text-2xl font-semibold">Anonymous Usage Stats</h1>
+        <p className="text-sm text-muted-foreground">
+          Bulwark sends one anonymous heartbeat per day so we can see how many instances are
+          running, on what platforms, and which features they use. <strong>Enabled by default</strong>;
+          one click below disables it. No email addresses, no hostnames, no IPs are sent.{' '}
+          <a
+            href="https://bulwarkmail.org/docs/legal/privacy/telemetry"
+            target="_blank"
+            rel="noreferrer"
+            className="underline inline-flex items-center gap-1"
+          >
+            Full schema and policy <ExternalLink className="h-3 w-3" />
+          </a>
+        </p>
+      </header>
+
+      <section className="rounded-lg border p-4 space-y-3">
+        <div className="flex items-center justify-between">
+          <div>
+            <div className="font-medium">Status</div>
+            <div className="text-sm text-muted-foreground">
+              {status.consent === 'pending' && 'Initialising - no heartbeats sent yet.'}
+              {status.consent === 'on' && 'Heartbeats are enabled (default).'}
+              {status.consent === 'off' && 'Heartbeats are off.'}
+              {envOverridden && (
+                <> Locked by <code>BULWARK_TELEMETRY</code> env var.</>
+              )}
+            </div>
+          </div>
+          <div className="flex gap-2">
+            <button
+              type="button"
+              disabled={busy === 'consent' || envOverridden || isOn}
+              onClick={() => void setConsent('on')}
+              className="px-3 py-1.5 rounded-md border bg-primary text-primary-foreground hover:bg-primary/90 disabled:opacity-50"
+            >
+              Enable
+            </button>
+            <button
+              type="button"
+              disabled={busy === 'consent' || envOverridden || status.consent === 'off'}
+              onClick={() => void setConsent('off')}
+              className="px-3 py-1.5 rounded-md border hover:bg-accent disabled:opacity-50"
+            >
+              Disable
+            </button>
+          </div>
+        </div>
+        <dl className="grid grid-cols-2 gap-2 text-sm pt-2 border-t">
+          <dt className="text-muted-foreground">Last sent</dt>
+          <dd>{timeAgo(status.lastSentAt)}</dd>
+          <dt className="text-muted-foreground">Next scheduled</dt>
+          <dd>{timeAgo(status.nextScheduledAt)}</dd>
+          <dt className="text-muted-foreground">Consented at</dt>
+          <dd>{status.consentedAt ? new Date(status.consentedAt).toLocaleString() : '-'}</dd>
+        </dl>
+      </section>
+
+      <section className="rounded-lg border p-4 space-y-2">
+        <div className="font-medium">Account activity</div>
+        <p className="text-sm text-muted-foreground">
+          Unique accounts that have logged in over the last 90 days. Identities are stored as a
+          per-instance HMAC, never as plaintext usernames. These are the numbers reported in the
+          heartbeat as bucketed ranges.
+        </p>
+        <dl className="grid grid-cols-2 gap-2 text-sm pt-1">
+          <dt className="text-muted-foreground">Total (90d)</dt>
+          <dd className="font-mono">{status.accountCounts?.total ?? 0}</dd>
+          <dt className="text-muted-foreground">Active (7d)</dt>
+          <dd className="font-mono">{status.accountCounts?.active7d ?? 0}</dd>
+        </dl>
+      </section>
+
+      <section className="rounded-lg border p-4 space-y-3">
+        <div className="font-medium">Endpoint</div>
+        <p className="text-sm text-muted-foreground">
+          Where heartbeats are sent. Defaults to the project's collector. Point at your own collector
+          (open source at <code>bulwarkmail/dashboard</code>) or clear this field to disable sending.
+        </p>
+        <div className="flex gap-2">
+          <input
+            type="url"
+            value={endpointDraft}
+            onChange={(e) => setEndpointDraft(e.target.value)}
+            placeholder={status.defaultEndpoint}
+            className="flex-1 px-3 py-1.5 rounded-md border bg-background"
+          />
+          <button
+            type="button"
+            disabled={busy === 'endpoint' || endpointDraft === status.endpoint}
+            onClick={() => void saveEndpoint()}
+            className="px-3 py-1.5 rounded-md border bg-primary text-primary-foreground hover:bg-primary/90 disabled:opacity-50 inline-flex items-center gap-1"
+          >
+            <Save className="h-4 w-4" /> Save
+          </button>
+        </div>
+      </section>
+
+      <section className="rounded-lg border p-4 space-y-3">
+        <div className="flex items-center justify-between">
+          <div>
+            <div className="font-medium">Payload preview</div>
+            <div className="text-sm text-muted-foreground">
+              Exactly what the next heartbeat would send from this install, right now.
+            </div>
+          </div>
+          <button
+            type="button"
+            disabled={busy === 'send' || !isOn}
+            onClick={() => void sendNow()}
+            className="px-3 py-1.5 rounded-md border bg-primary text-primary-foreground hover:bg-primary/90 disabled:opacity-50 inline-flex items-center gap-1"
+          >
+            <Send className="h-4 w-4" /> Send now
+          </button>
+        </div>
+        {sendResult && (
+          <div
+            className={`text-sm flex items-center gap-2 ${
+              sendResult.ok ? 'text-emerald-600' : 'text-red-600'
+            }`}
+          >
+            {sendResult.ok ? <CheckCircle2 className="h-4 w-4" /> : <XCircle className="h-4 w-4" />}
+            {sendResult.msg}
+          </div>
+        )}
+        <pre className="text-xs bg-muted/50 rounded-md p-3 overflow-x-auto max-h-96">
+          {JSON.stringify(status.payloadPreview, null, 2)}
+        </pre>
+      </section>
+    </div>
+  );
+}

app/api/admin/branding/[filename]/route.ts

@@ -53,11 +53,19 @@ export async function GET(
 
     const buffer = await readFile(resolved);
 
+    // SVG can carry inline <script> and event handlers that execute when the
+    // file is fetched as a top-level document. Defense in depth on top of
+    // admin-only upload: nosniff blocks MIME confusion, the CSP forces a
+    // sandboxed unique origin so any script in an SVG is inert and cannot
+    // touch app cookies or storage.
     return new NextResponse(buffer, {
       headers: {
         'Content-Type': contentType,
         'Cache-Control': 'public, max-age=3600, must-revalidate',
         'Content-Length': String(buffer.length),
+        'X-Content-Type-Options': 'nosniff',
+        'Content-Security-Policy':
+          "default-src 'none'; img-src 'self' data:; style-src 'unsafe-inline'; sandbox",
       },
     });
   } catch {

app/api/admin/marketplace/[slug]/route.ts

@@ -0,0 +1,214 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { requireAdminAuth } from '@/lib/admin/session';
+import { logger } from '@/lib/logger';
+import {
+  getPluginRegistry,
+  getThemeRegistry,
+} from '@/lib/admin/plugin-registry';
+import JSZip from 'jszip';
+import { MAX_PLUGIN_SIZE, MAX_THEME_SIZE } from '@/lib/plugin-types';
+
+const DIRECTORY_URL = process.env.EXTENSION_DIRECTORY_URL || 'https://extensions.bulwarkmail.org';
+
+const MAX_PREVIEW_SOURCE_LEN = 100_000;
+
+/**
+ * GET /api/admin/marketplace/[slug]
+ * Returns full preview info for an extension: directory metadata,
+ * the bundle's manifest, a (truncated) source preview, and install status.
+ * Lets admins audit what they're about to install before pressing the button.
+ */
+export async function GET(
+  _request: NextRequest,
+  { params }: { params: Promise<{ slug: string }> },
+) {
+  try {
+    const result = await requireAdminAuth();
+    if ('error' in result) return result.error;
+
+    const { slug } = await params;
+
+    // 1. Extension metadata + screenshots + theme previews from the directory
+    const detailUrl = new URL(`/api/v1/extension/${encodeURIComponent(slug)}`, DIRECTORY_URL);
+    const detailRes = await fetch(detailUrl.toString(), {
+      headers: { Accept: 'application/json' },
+      signal: AbortSignal.timeout(10000),
+    });
+
+    if (!detailRes.ok) {
+      const status = detailRes.status === 404 ? 404 : 502;
+      return NextResponse.json(
+        { error: status === 404 ? 'Extension not found' : 'Directory request failed' },
+        { status },
+      );
+    }
+
+    const detailJson = await detailRes.json();
+    const extension = detailJson.data as Record<string, unknown> | undefined;
+    if (!extension) {
+      return NextResponse.json({ error: 'Extension not found' }, { status: 404 });
+    }
+
+    const type = extension.type as 'plugin' | 'theme';
+    const latestVersion = (extension.latestVersion as { version?: string } | null)?.version
+      ?? null;
+
+    // 2. Pull the bundle so we can show what's actually inside.
+    let manifest: Record<string, unknown> | null = null;
+    let sourcePreview: { name: string; content: string; truncated: boolean } | null = null;
+    let bundleError: string | null = null;
+    let bundleSize = 0;
+
+    if (latestVersion) {
+      try {
+        const bundleUrl = new URL(
+          `/api/v1/bundle/${encodeURIComponent(slug)}/${encodeURIComponent(latestVersion)}`,
+          DIRECTORY_URL,
+        );
+        const bundleRes = await fetch(bundleUrl.toString(), {
+          signal: AbortSignal.timeout(30000),
+        });
+
+        if (!bundleRes.ok) {
+          bundleError = `Bundle download failed (${bundleRes.status})`;
+        } else {
+          const buffer = await bundleRes.arrayBuffer();
+          bundleSize = buffer.byteLength;
+          const maxSize = type === 'theme' ? MAX_THEME_SIZE : MAX_PLUGIN_SIZE;
+          if (buffer.byteLength > maxSize) {
+            bundleError = `Bundle exceeds ${type === 'theme' ? '1 MB' : '5 MB'} size limit`;
+          } else {
+            const zip = await JSZip.loadAsync(buffer);
+
+            // Detect optional root directory inside the ZIP.
+            const entries = Object.keys(zip.files);
+            const topDirs = new Set(entries.map((e) => e.split('/')[0]));
+            let root = '';
+            if (topDirs.size === 1) {
+              const dir = [...topDirs][0];
+              if (zip.files[dir + '/'] || entries.some((e) => e.startsWith(dir + '/'))) {
+                root = dir + '/';
+              }
+            }
+
+            const manifestFile = zip.file(root + 'manifest.json');
+            if (!manifestFile) {
+              bundleError = 'Bundle missing manifest.json';
+            } else {
+              try {
+                manifest = JSON.parse(await manifestFile.async('string'));
+              } catch {
+                bundleError = 'Invalid manifest.json in bundle';
+              }
+            }
+
+            if (manifest) {
+              if (type === 'theme') {
+                const cssFile = zip.file(root + 'theme.css');
+                if (cssFile) {
+                  const css = await cssFile.async('string');
+                  sourcePreview = {
+                    name: 'theme.css',
+                    content: css.length > MAX_PREVIEW_SOURCE_LEN
+                      ? css.slice(0, MAX_PREVIEW_SOURCE_LEN)
+                      : css,
+                    truncated: css.length > MAX_PREVIEW_SOURCE_LEN,
+                  };
+                }
+              } else {
+                const entrypoint = (manifest.entrypoint as string) || 'index.js';
+                const jsFile = zip.file(root + entrypoint);
+                if (jsFile) {
+                  const code = await jsFile.async('string');
+                  sourcePreview = {
+                    name: entrypoint,
+                    content: code.length > MAX_PREVIEW_SOURCE_LEN
+                      ? code.slice(0, MAX_PREVIEW_SOURCE_LEN)
+                      : code,
+                    truncated: code.length > MAX_PREVIEW_SOURCE_LEN,
+                  };
+                }
+              }
+            }
+          }
+        }
+      } catch (err) {
+        bundleError = err instanceof Error ? err.message : 'Failed to read bundle';
+      }
+    } else {
+      bundleError = 'Extension has no published version';
+    }
+
+    // 3. Install status (slug is used as the registry id at install time)
+    const [pluginRegistry, themeRegistry] = await Promise.all([
+      getPluginRegistry(),
+      getThemeRegistry(),
+    ]);
+    const installed = type === 'theme'
+      ? themeRegistry.themes.some((t) => t.id === slug)
+      : pluginRegistry.plugins.some((p) => p.id === slug);
+
+    // 4. Build screenshot URLs (proxy through the directory's public files endpoint).
+    const screenshots = Array.isArray(extension.screenshots)
+      ? (extension.screenshots as Array<{ path: string; altText?: string | null }>).map((s) => ({
+          url: new URL(`/api/v1/files/${s.path}`, DIRECTORY_URL).toString(),
+          altText: s.altText ?? null,
+        }))
+      : [];
+
+    // Strip the heavy `manifest` blob from versions when echoing the directory data.
+    const versions = Array.isArray(extension.versions)
+      ? (extension.versions as Array<Record<string, unknown>>).map((v) => ({
+          version: v.version,
+          changelog: v.changelog,
+          bundleSize: v.bundleSize,
+          minAppVersion: v.minAppVersion,
+          publishedAt: v.publishedAt,
+          permissions: v.permissions,
+        }))
+      : [];
+
+    return NextResponse.json(
+      {
+        extension: {
+          slug: extension.slug,
+          name: extension.name,
+          type: extension.type,
+          pluginType: extension.pluginType ?? null,
+          description: extension.description,
+          longDescription: extension.longDescription ?? null,
+          tags: extension.tags ?? [],
+          permissions: extension.permissions ?? [],
+          totalDownloads: extension.totalDownloads ?? 0,
+          featured: extension.featured ?? false,
+          githubRepo: extension.githubRepo ?? null,
+          license: extension.license ?? null,
+          minAppVersion: extension.minAppVersion ?? null,
+          author: extension.author ?? null,
+          latestVersion,
+          versions,
+          screenshots,
+          themePreviews: extension.themePreviews ?? [],
+          createdAt: extension.createdAt ?? null,
+          updatedAt: extension.updatedAt ?? null,
+        },
+        bundle: {
+          manifest,
+          source: sourcePreview,
+          size: bundleSize,
+          error: bundleError,
+        },
+        installed,
+      },
+      { headers: { 'Cache-Control': 'no-store' } },
+    );
+  } catch (error) {
+    logger.error('Marketplace preview error', {
+      error: error instanceof Error ? error.message : 'Unknown error',
+    });
+    return NextResponse.json(
+      { error: 'Failed to load preview' },
+      { status: 502 },
+    );
+  }
+}

app/api/admin/marketplace/route.ts

@@ -10,11 +10,15 @@ import {
   type ServerPlugin,
   type ServerTheme,
 } from '@/lib/admin/plugin-registry';
+import {
+  sanitizeFrameOrigins,
+  invalidateFrameOriginsCache,
+} from '@/lib/admin/csp-frame-origins';
 import JSZip from 'jszip';
 import { MAX_PLUGIN_SIZE, MAX_THEME_SIZE, ALL_PERMISSIONS, ALLOWED_PLUGIN_FILES } from '@/lib/plugin-types';
 import { sanitizeThemeCSS, validateThemeCSSSafety } from '@/lib/theme-loader';
 
-const DIRECTORY_URL = process.env.EXTENSION_DIRECTORY_URL || 'http://localhost:3001';
+const DIRECTORY_URL = process.env.EXTENSION_DIRECTORY_URL || 'https://extensions.bulwarkmail.org';
 
 /**
  * GET /api/admin/marketplace - Search/browse the extension directory
@@ -226,6 +230,22 @@ export async function POST(request: NextRequest) {
         warnings.push(`Unknown permissions: ${unknownPerms.join(', ')}`);
       }
 
+      // Plugins may declare iframe origins they need for embedded content.
+      // Anything that doesn't pass strict origin validation is silently
+      // dropped - the plugin still installs, but those origins are not
+      // added to the host CSP.
+      const declaredFrameOrigins = sanitizeFrameOrigins(manifest.frameOrigins);
+      const droppedFrameOrigins = Array.isArray(manifest.frameOrigins)
+        ? (manifest.frameOrigins as unknown[]).filter(
+            (v) => typeof v !== 'string' || !declaredFrameOrigins.includes(v),
+          )
+        : [];
+      if (droppedFrameOrigins.length > 0) {
+        warnings.push(
+          `Ignored invalid frameOrigins: ${droppedFrameOrigins.join(', ')}`,
+        );
+      }
+
       const plugin: ServerPlugin = {
         id: (manifest.id as string) || slug,
         name: (manifest.name as string) || slug,
@@ -238,10 +258,14 @@ export async function POST(request: NextRequest) {
         enabled: true,
         installedAt: now,
         updatedAt: now,
+        ...(declaredFrameOrigins.length > 0
+          ? { frameOrigins: declaredFrameOrigins }
+          : {}),
       };
 
       await savePlugin(plugin, code);
-      await auditLog('marketplace.install_plugin', { id: plugin.id, name: plugin.name, version: plugin.version, slug }, ip);
+      invalidateFrameOriginsCache();
+      await auditLog('marketplace.install_plugin', { id: plugin.id, name: plugin.name, version: plugin.version, slug, frameOrigins: declaredFrameOrigins }, ip);
 
       return NextResponse.json({ success: true, plugin, warnings });
     }

app/api/admin/oauth/setup/route.ts

@@ -139,7 +139,7 @@ export async function POST(request: NextRequest) {
     const queryEntry = queryRes.methodResponses?.[0];
     if (!queryEntry || queryEntry[0] === 'error') {
       return NextResponse.json({
-        error: 'Stalwart denied OAuthClient/query — your Stalwart account likely lacks admin permissions.',
+        error: 'Stalwart denied OAuthClient/query - your Stalwart account likely lacks admin permissions.',
         detail: queryEntry?.[1],
       }, { status: 403 });
     }
@@ -187,7 +187,7 @@ export async function POST(request: NextRequest) {
     const setEntry = setRes.methodResponses?.[0];
     if (!setEntry || setEntry[0] === 'error') {
       return NextResponse.json({
-        error: 'Stalwart denied OAuthClient/set — admin permissions required.',
+        error: 'Stalwart denied OAuthClient/set - admin permissions required.',
         detail: setEntry?.[1],
       }, { status: 403 });
     }

app/api/admin/plugins/[id]/config/route.ts

@@ -2,15 +2,20 @@ import { NextRequest, NextResponse } from 'next/server';
 import { getPlugin } from '@/lib/admin/plugin-registry';
 import { getPluginConfig, setPluginConfig, deletePluginConfigKey } from '@/lib/admin/plugin-config';
 import { requireAdminAuth } from '@/lib/admin/session';
+import { getStalwartCredentials } from '@/lib/stalwart/credentials';
 
 /**
- * GET /api/admin/plugins/[id]/config - Read all config for a plugin
+ * GET /api/admin/plugins/[id]/config - Read plugin config
  *
- * Returns the full config object for admin-configured plugin settings.
- * This endpoint is accessible from the client-side plugin API.
+ * - Admin sessions receive every field, including those declared
+ *   `type: 'secret'` in the plugin's configSchema.
+ * - Authenticated mailbox users (the plugin running in their browser)
+ *   receive only non-secret fields.
+ * - Anonymous callers are rejected so unauthenticated visitors cannot
+ *   enumerate plugin secrets.
  */
 export async function GET(
-  _request: NextRequest,
+  request: NextRequest,
   { params }: { params: Promise<{ id: string }> },
 ) {
   try {
@@ -20,13 +25,34 @@ export async function GET(
       return NextResponse.json({ error: 'Invalid plugin ID' }, { status: 400 });
     }
 
+    const adminAuth = await requireAdminAuth();
+    const isAdmin = !('error' in adminAuth);
+
+    if (!isAdmin) {
+      const creds = await getStalwartCredentials(request);
+      if (!creds) {
+        return NextResponse.json({ error: 'Not authenticated' }, { status: 401 });
+      }
+    }
+
     const plugin = await getPlugin(id);
     if (!plugin) {
       return NextResponse.json({ error: 'Plugin not found' }, { status: 404 });
     }
 
     const config = await getPluginConfig(id);
-    return NextResponse.json(config, {
+
+    let response: Record<string, unknown> = config;
+    if (!isAdmin && plugin.configSchema) {
+      response = {};
+      for (const [key, value] of Object.entries(config)) {
+        const field = plugin.configSchema[key];
+        if (field?.type === 'secret') continue;
+        response[key] = value;
+      }
+    }
+
+    return NextResponse.json(response, {
       headers: { 'Cache-Control': 'no-store' },
     });
   } catch {

app/api/admin/plugins/route.ts

@@ -8,6 +8,10 @@ import {
   deletePlugin as removePlugin,
   type ServerPlugin,
 } from '@/lib/admin/plugin-registry';
+import {
+  sanitizeFrameOrigins,
+  invalidateFrameOriginsCache,
+} from '@/lib/admin/csp-frame-origins';
 
 // Server-side extraction using the same validation logic
 // ZIP parsing needs to happen on the server for admin-uploaded plugins
@@ -152,6 +156,8 @@ export async function POST(request: NextRequest) {
       );
     }
 
+    const declaredFrameOrigins = sanitizeFrameOrigins(manifest.frameOrigins);
+
     const now = new Date().toISOString();
     const plugin: ServerPlugin = {
       id: manifest.id as string,
@@ -166,12 +172,16 @@ export async function POST(request: NextRequest) {
       ...(manifest.configSchema && typeof manifest.configSchema === 'object'
         ? { configSchema: manifest.configSchema as ServerPlugin['configSchema'] }
         : {}),
+      ...(declaredFrameOrigins.length > 0
+        ? { frameOrigins: declaredFrameOrigins }
+        : {}),
       installedAt: now,
       updatedAt: now,
     };
 
     await savePlugin(plugin, code);
-    await auditLog('plugin.install', { id: plugin.id, name: plugin.name, version: plugin.version }, ip);
+    invalidateFrameOriginsCache();
+    await auditLog('plugin.install', { id: plugin.id, name: plugin.name, version: plugin.version, frameOrigins: declaredFrameOrigins }, ip);
 
     return NextResponse.json({ plugin });
   } catch (error) {
@@ -209,6 +219,11 @@ export async function PATCH(request: NextRequest) {
       return NextResponse.json({ error: 'Plugin not found' }, { status: 404 });
     }
 
+    // Enable/disable changes the set of plugins contributing frame origins.
+    if (typeof updates.enabled === 'boolean' || typeof updates.forceEnabled === 'boolean') {
+      invalidateFrameOriginsCache();
+    }
+
     await auditLog('plugin.update', { id, ...updates }, ip);
     return NextResponse.json({ plugin: updated });
   } catch (error) {
@@ -238,6 +253,7 @@ export async function DELETE(request: NextRequest) {
       return NextResponse.json({ error: 'Plugin not found' }, { status: 404 });
     }
 
+    invalidateFrameOriginsCache();
     await auditLog('plugin.delete', { id }, ip);
     return NextResponse.json({ success: true });
   } catch (error) {

app/api/admin/telemetry/route.ts

@@ -0,0 +1,135 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { requireAdminAuth, getClientIP } from '@/lib/admin/session';
+import { auditLog } from '@/lib/admin/audit';
+import { logger } from '@/lib/logger';
+import {
+  effectiveConsent,
+  loadState,
+  saveState,
+  buildPayload,
+  sendOnce,
+  reschedule,
+  DEFAULT_ENDPOINT,
+  getLoginCounts,
+  resolveEndpointAllowed,
+} from '@/lib/telemetry';
+
+/**
+ * GET /api/admin/telemetry
+ * Returns current consent + endpoint + next/last send + a live preview
+ * of exactly what the next heartbeat would contain.
+ */
+export async function GET() {
+  try {
+    const auth = await requireAdminAuth();
+    if ('error' in auth) return auth.error;
+
+    const { consent, source, state } = await effectiveConsent();
+    const [payload, accountCounts] = await Promise.all([
+      buildPayload(),
+      getLoginCounts(),
+    ]);
+
+    return NextResponse.json(
+      {
+        consent,
+        consentSource: source,
+        endpoint: state.endpoint || DEFAULT_ENDPOINT,
+        consentedAt: state.consentedAt,
+        lastSentAt: state.lastSentAt,
+        nextScheduledAt: state.nextScheduledAt,
+        defaultEndpoint: DEFAULT_ENDPOINT,
+        payloadPreview: payload,
+        accountCounts,
+      },
+      { headers: { 'Cache-Control': 'no-store' } },
+    );
+  } catch (err) {
+    logger.error('telemetry GET error', {
+      error: err instanceof Error ? err.message : 'unknown',
+    });
+    return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
+  }
+}
+
+/**
+ * POST /api/admin/telemetry
+ * Body: { action: 'set-consent' | 'set-endpoint' | 'send-now', ... }
+ *   set-consent  : { action, consent: 'on' | 'off' }
+ *   set-endpoint : { action, endpoint: string }
+ *   send-now     : { action }
+ */
+export async function POST(request: NextRequest) {
+  try {
+    const auth = await requireAdminAuth();
+    if ('error' in auth) return auth.error;
+    const ip = getClientIP(request);
+
+    const body = (await request.json().catch(() => null)) as
+      | { action?: string; consent?: string; endpoint?: string }
+      | null;
+    if (!body || typeof body.action !== 'string') {
+      return NextResponse.json({ error: 'action required' }, { status: 400 });
+    }
+
+    const { source } = await effectiveConsent();
+
+    if (body.action === 'set-consent') {
+      if (source === 'env') {
+        return NextResponse.json(
+          { error: 'consent is overridden by BULWARK_TELEMETRY env var' },
+          { status: 409 },
+        );
+      }
+      if (body.consent !== 'on' && body.consent !== 'off') {
+        return NextResponse.json({ error: 'consent must be "on" or "off"' }, { status: 400 });
+      }
+      const state = await loadState();
+      const before = state.consent;
+      state.consent = body.consent;
+      if (body.consent === 'on' && !state.consentedAt) {
+        state.consentedAt = new Date().toISOString();
+      }
+      await saveState(state);
+      await reschedule();
+      await auditLog('telemetry.set-consent', { from: before, to: body.consent }, ip);
+      return NextResponse.json({ ok: true });
+    }
+
+    if (body.action === 'set-endpoint') {
+      if (typeof body.endpoint !== 'string') {
+        return NextResponse.json({ error: 'endpoint required' }, { status: 400 });
+      }
+      const trimmed = body.endpoint.trim();
+      if (trimmed) {
+        const check = await resolveEndpointAllowed(trimmed);
+        if (!check.ok) {
+          return NextResponse.json({ error: check.reason }, { status: 400 });
+        }
+      }
+      const state = await loadState();
+      const before = state.endpoint;
+      state.endpoint = trimmed || DEFAULT_ENDPOINT;
+      await saveState(state);
+      await auditLog('telemetry.set-endpoint', { from: before, to: state.endpoint }, ip);
+      return NextResponse.json({ ok: true, endpoint: state.endpoint });
+    }
+
+    if (body.action === 'send-now') {
+      const result = await sendOnce({ reason: 'admin-manual' });
+      await auditLog(
+        'telemetry.send-now',
+        { ok: result.ok, status: result.status ?? null, error: result.error ?? null },
+        ip,
+      );
+      return NextResponse.json(result, { status: result.ok ? 200 : 502 });
+    }
+
+    return NextResponse.json({ error: 'unknown action' }, { status: 400 });
+  } catch (err) {
+    logger.error('telemetry POST error', {
+      error: err instanceof Error ? err.message : 'unknown',
+    });
+    return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
+  }
+}

app/api/auth/session/route.ts

@@ -10,6 +10,8 @@ import {
   setStalwartAuthContextInStore,
 } from '@/lib/stalwart/auth-context';
 import { configManager } from '@/lib/admin/config-manager';
+import { isPublicHttpUrl } from '@/lib/security/url-guard';
+import { recordLogin } from '@/lib/telemetry/login-tracker';
 
 const COOKIE_OPTIONS = {
   ...getCookieOptions(),
@@ -37,10 +39,37 @@ export async function POST(request: NextRequest) {
       return NextResponse.json({ error: 'Missing required fields' }, { status: 400 });
     }
 
+    // Pin the upstream URL to the configured JMAP server so an unauthenticated
+    // caller cannot point this route at internal hosts. Only when no server URL
+    // is configured AND the deployment explicitly allows custom JMAP endpoints
+    // do we honor the body URL — and even then it must be a public URL.
+    await configManager.ensureLoaded();
+    const configuredServerUrl =
+      configManager.get<string>('jmapServerUrl', '') ||
+      process.env.JMAP_SERVER_URL ||
+      process.env.NEXT_PUBLIC_JMAP_SERVER_URL ||
+      '';
+    const allowCustomEndpoint = configManager.get<boolean>('allowCustomJmapEndpoint', false);
+
+    let upstreamUrl: string;
+    let upstreamTrusted: boolean;
+    if (configuredServerUrl) {
+      upstreamUrl = configuredServerUrl;
+      upstreamTrusted = true;
+    } else if (allowCustomEndpoint) {
+      if (!(await isPublicHttpUrl(serverUrl))) {
+        return NextResponse.json({ error: 'Server URL is not allowed' }, { status: 400 });
+      }
+      upstreamUrl = serverUrl;
+      upstreamTrusted = false;
+    } else {
+      return NextResponse.json({ error: 'JMAP server not configured' }, { status: 500 });
+    }
+
     const slot = typeof bodySlot === 'number' && bodySlot >= 0 && bodySlot <= 4 ? bodySlot : getSlot(request);
     const cookieName = sessionCookieName(slot);
     const authHeader = `Basic ${Buffer.from(`${username}:${password}`).toString('base64')}`;
-    const normalizedServerUrl = await verifyJmapAuth(serverUrl, authHeader);
+    const normalizedServerUrl = await verifyJmapAuth(upstreamUrl, authHeader, { trusted: upstreamTrusted });
     const token = encryptSession(normalizedServerUrl, username, password);
     const cookieStore = await cookies();
     cookieStore.set(cookieName, token, COOKIE_OPTIONS);
@@ -50,6 +79,8 @@ export async function POST(request: NextRequest) {
       authHeader,
     });
 
+    void recordLogin(username, normalizedServerUrl);
+
     return NextResponse.json({ ok: true });
   } catch (error) {
     if (error instanceof JmapAuthVerificationError) {

app/api/auth/stalwart-context/route.ts

@@ -2,6 +2,9 @@ import { NextRequest, NextResponse } from 'next/server';
 import { logger } from '@/lib/logger';
 import { JmapAuthVerificationError, verifyJmapAuth } from '@/lib/auth/verify-jmap-auth';
 import { setStalwartAuthContext } from '@/lib/stalwart/auth-context';
+import { configManager } from '@/lib/admin/config-manager';
+import { isPublicHttpUrl } from '@/lib/security/url-guard';
+import { recordLogin } from '@/lib/telemetry/login-tracker';
 
 function getSlot(request: NextRequest, bodySlot: unknown): number {
   if (typeof bodySlot === 'number' && bodySlot >= 0 && bodySlot <= 4) {
@@ -23,8 +26,35 @@ export async function POST(request: NextRequest) {
       return NextResponse.json({ error: 'Missing required fields' }, { status: 400 });
     }
 
+    // Pin the upstream URL to the configured JMAP server so an unauthenticated
+    // caller cannot point this route at internal hosts. Only when no server URL
+    // is configured AND the deployment explicitly allows custom JMAP endpoints
+    // do we honor the body URL — and even then it must be a public URL.
+    await configManager.ensureLoaded();
+    const configuredServerUrl =
+      configManager.get<string>('jmapServerUrl', '') ||
+      process.env.JMAP_SERVER_URL ||
+      process.env.NEXT_PUBLIC_JMAP_SERVER_URL ||
+      '';
+    const allowCustomEndpoint = configManager.get<boolean>('allowCustomJmapEndpoint', false);
+
+    let upstreamUrl: string;
+    let upstreamTrusted: boolean;
+    if (configuredServerUrl) {
+      upstreamUrl = configuredServerUrl;
+      upstreamTrusted = true;
+    } else if (allowCustomEndpoint) {
+      if (!(await isPublicHttpUrl(serverUrl))) {
+        return NextResponse.json({ error: 'Server URL is not allowed' }, { status: 400 });
+      }
+      upstreamUrl = serverUrl;
+      upstreamTrusted = false;
+    } else {
+      return NextResponse.json({ error: 'JMAP server not configured' }, { status: 500 });
+    }
+
     const slot = getSlot(request, bodySlot);
-    const normalizedServerUrl = await verifyJmapAuth(serverUrl, authHeader);
+    const normalizedServerUrl = await verifyJmapAuth(upstreamUrl, authHeader, { trusted: upstreamTrusted });
 
     await setStalwartAuthContext(slot, {
       serverUrl: normalizedServerUrl,
@@ -32,6 +62,8 @@ export async function POST(request: NextRequest) {
       authHeader,
     });
 
+    void recordLogin(username, normalizedServerUrl);
+
     return NextResponse.json({ ok: true });
   } catch (error) {
     if (error instanceof JmapAuthVerificationError) {

app/api/auth/totp-token-exchange/route.ts

@@ -6,6 +6,8 @@ import { refreshTokenCookieName } from '@/lib/oauth/tokens';
 import { getCookieOptions } from '@/lib/oauth/cookie-config';
 import { readFileEnv } from '@/lib/read-file-env';
 import { configManager } from '@/lib/admin/config-manager';
+import { isPublicHttpUrl } from '@/lib/security/url-guard';
+import { recordLogin } from '@/lib/telemetry/login-tracker';
 
 /**
  * Exchange basic auth credentials (with TOTP appended) for OAuth tokens.
@@ -84,22 +86,39 @@ export async function POST(request: NextRequest) {
 
     const slot = typeof bodySlot === 'number' && bodySlot >= 0 && bodySlot <= 4 ? bodySlot : 0;
 
-    // Use the server-side JMAP_SERVER_URL if set (may differ from the
-    // public URL the browser uses, e.g. inside Docker).
-    const internalServerUrl = process.env.JMAP_SERVER_URL || process.env.NEXT_PUBLIC_JMAP_SERVER_URL || serverUrl;
+    // Pin the upstream URL to the configured JMAP server so an unauthenticated
+    // caller cannot point this route at internal hosts. Only when no server
+    // URL is configured (and the deployment explicitly allows custom JMAP
+    // endpoints) do we fall back to the user-supplied URL - and even then
+    // it must resolve to a public address.
+    await configManager.ensureLoaded();
+    const configuredServerUrl =
+      configManager.get<string>('jmapServerUrl', '') ||
+      process.env.JMAP_SERVER_URL ||
+      process.env.NEXT_PUBLIC_JMAP_SERVER_URL ||
+      '';
+    const allowCustomEndpoint = configManager.get<boolean>('allowCustomJmapEndpoint', false);
 
-    const tokenEndpoint = await findTokenEndpoint(internalServerUrl);
-    if (!tokenEndpoint) {
-      // Also try with the client-provided URL in case the internal one differs
-      const clientEndpoint = internalServerUrl !== serverUrl ? await findTokenEndpoint(serverUrl) : null;
-      if (!clientEndpoint) {
-        logger.warn('TOTP token exchange: no token endpoint found', { serverUrl, internalServerUrl });
-        return NextResponse.json({ error: 'no_token_endpoint', detail: 'Could not discover OAuth token endpoint on the mail server' }, { status: 404 });
+    let upstreamUrl: string;
+    if (configuredServerUrl) {
+      upstreamUrl = configuredServerUrl;
+    } else if (allowCustomEndpoint) {
+      if (!(await isPublicHttpUrl(serverUrl))) {
+        logger.warn('TOTP token exchange: rejected non-public server URL');
+        return NextResponse.json({ error: 'invalid_server_url' }, { status: 400 });
       }
-      return await attemptAllStrategies(clientEndpoint, username, password, slot);
+      upstreamUrl = serverUrl;
+    } else {
+      return NextResponse.json({ error: 'jmap_server_not_configured' }, { status: 500 });
     }
 
-    return await attemptAllStrategies(tokenEndpoint, username, password, slot);
+    const tokenEndpoint = await findTokenEndpoint(upstreamUrl);
+    if (!tokenEndpoint) {
+      logger.warn('TOTP token exchange: no token endpoint found');
+      return NextResponse.json({ error: 'no_token_endpoint', detail: 'Could not discover OAuth token endpoint on the mail server' }, { status: 404 });
+    }
+
+    return await attemptAllStrategies(tokenEndpoint, upstreamUrl, username, password, slot);
   } catch (error) {
     logger.error('TOTP token exchange error', { error: error instanceof Error ? error.message : 'Unknown error' });
     return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
@@ -108,6 +127,7 @@ export async function POST(request: NextRequest) {
 
 async function attemptAllStrategies(
   tokenEndpoint: string,
+  serverUrl: string,
   username: string,
   password: string,
   slot: number,
@@ -126,6 +146,7 @@ async function attemptAllStrategies(
     const result = await tryTokenRequest(tokenEndpoint, params);
     if (result.ok) {
       logger.info('TOTP token exchange succeeded (ROPC with client_id)');
+      void recordLogin(username, serverUrl);
       return await storeAndRespond(result.tokens, slot);
     }
     attempts.push({ strategy: 'ROPC with client_id', error: result.error });
@@ -137,6 +158,7 @@ async function attemptAllStrategies(
     const result = await tryTokenRequest(tokenEndpoint, params);
     if (result.ok) {
       logger.info('TOTP token exchange succeeded (ROPC without client_id)');
+      void recordLogin(username, serverUrl);
       return await storeAndRespond(result.tokens, slot);
     }
     attempts.push({ strategy: 'ROPC without client_id', error: result.error });
@@ -148,6 +170,7 @@ async function attemptAllStrategies(
     const result = await tryTokenRequest(tokenEndpoint, params, { 'Authorization': basicAuth });
     if (result.ok) {
       logger.info('TOTP token exchange succeeded (Basic Auth header)');
+      void recordLogin(username, serverUrl);
       return await storeAndRespond(result.tokens, slot);
     }
     attempts.push({ strategy: 'Basic Auth header', error: result.error });
@@ -159,6 +182,7 @@ async function attemptAllStrategies(
     const result = await tryTokenRequest(tokenEndpoint, params, { 'Authorization': basicAuth });
     if (result.ok) {
       logger.info('TOTP token exchange succeeded (client_credentials + Basic Auth)');
+      void recordLogin(username, serverUrl);
       return await storeAndRespond(result.tokens, slot);
     }
     attempts.push({ strategy: 'client_credentials + Basic Auth', error: result.error });

app/api/fetch-ical/route.ts

@@ -1,89 +1,9 @@
-import { lookup } from 'node:dns/promises';
-import { BlockList, isIP } from 'node:net';
 import { NextRequest, NextResponse } from 'next/server';
+import { isPublicHttpUrl } from '@/lib/security/url-guard';
 
 const MAX_RESPONSE_SIZE = 10 * 1024 * 1024; // 10MB
 const FETCH_TIMEOUT_MS = 15000;
 
-const blockedAddressRanges = new BlockList();
-blockedAddressRanges.addAddress('0.0.0.0');
-blockedAddressRanges.addAddress('127.0.0.1');
-blockedAddressRanges.addSubnet('10.0.0.0', 8);
-blockedAddressRanges.addSubnet('172.16.0.0', 12);
-blockedAddressRanges.addSubnet('192.168.0.0', 16);
-blockedAddressRanges.addSubnet('169.254.0.0', 16);
-blockedAddressRanges.addAddress('::', 'ipv6');
-blockedAddressRanges.addAddress('::1', 'ipv6');
-blockedAddressRanges.addSubnet('fc00::', 7, 'ipv6');
-blockedAddressRanges.addSubnet('fe80::', 10, 'ipv6');
-
-function normalizeHostname(hostname: string): string {
-  return hostname.replace(/^\[(.*)\]$/, '$1').toLowerCase();
-}
-
-function isBlockedIpAddress(hostname: string): boolean {
-  const normalized = normalizeHostname(hostname);
-  const family = isIP(normalized);
-  if (family === 4) {
-    return blockedAddressRanges.check(normalized, 'ipv4');
-  }
-  if (family === 6) {
-    return blockedAddressRanges.check(normalized, 'ipv6');
-  }
-  return false;
-}
-
-async function isValidExternalUrl(urlString: string): Promise<boolean> {
-  let url: URL;
-  try {
-    url = new URL(urlString);
-  } catch {
-    return false;
-  }
-
-  if (url.protocol !== 'https:' && url.protocol !== 'http:') {
-    return false;
-  }
-
-  const hostname = normalizeHostname(url.hostname);
-
-  // Block private/internal hostnames
-  if (
-    hostname === 'localhost' ||
-    hostname.endsWith('.localhost') ||
-    hostname.endsWith('.local') ||
-    hostname.endsWith('.internal') ||
-    hostname.endsWith('.arpa') ||
-    hostname.endsWith('.localdomain')
-  ) {
-    return false;
-  }
-
-  // Block URLs with credentials
-  if (url.username || url.password) {
-    return false;
-  }
-
-  if (isBlockedIpAddress(hostname)) {
-    return false;
-  }
-
-  if (isIP(hostname)) {
-    return true;
-  }
-
-  try {
-    const records = await lookup(hostname, { all: true, verbatim: true });
-    if (records.length === 0) {
-      return false;
-    }
-    return records.every((record) => !isBlockedIpAddress(record.address));
-  } catch {
-    return false;
-  }
-
-}
-
 export async function POST(request: NextRequest) {
   let body: { url?: string };
   try {
@@ -98,7 +18,7 @@ export async function POST(request: NextRequest) {
     return NextResponse.json({ error: 'URL is required' }, { status: 400 });
   }
 
-  if (!(await isValidExternalUrl(url))) {
+  if (!(await isPublicHttpUrl(url))) {
     return NextResponse.json({ error: 'Invalid or disallowed URL' }, { status: 400 });
   }
 
@@ -111,7 +31,7 @@ export async function POST(request: NextRequest) {
     let response: Response | undefined;
 
     for (let i = 0; i <= MAX_REDIRECTS; i++) {
-      if (!(await isValidExternalUrl(currentUrl))) {
+      if (!(await isPublicHttpUrl(currentUrl))) {
         clearTimeout(timeout);
         return NextResponse.json({ error: 'Redirect to disallowed URL' }, { status: 400 });
       }
@@ -131,7 +51,6 @@ export async function POST(request: NextRequest) {
           clearTimeout(timeout);
           return NextResponse.json({ error: 'Redirect without Location header' }, { status: 502 });
         }
-        // Resolve relative redirects
         currentUrl = new URL(location, currentUrl).toString();
         continue;
       }

app/api/push/preview/route.ts

@@ -0,0 +1,140 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { logger } from '@/lib/logger';
+import { getStalwartCredentials } from '@/lib/stalwart/credentials';
+
+export const runtime = 'nodejs';
+export const dynamic = 'force-dynamic';
+
+/**
+ * GET /api/push/preview
+ *
+ * Called from the service worker when a Web Push wake-up arrives. Fetches the
+ * latest unread email so the SW can build an enriched system notification
+ * (sender, subject, avatar) without ever exposing JMAP credentials to the
+ * SW context.
+ *
+ * The relay's push payload is intentionally minimal (just a state-change
+ * ping), so this is what makes "From: Alice / Subject: …" appear instead of
+ * a generic "New mail" string.
+ */
+export async function GET(request: NextRequest) {
+  try {
+    const creds = await getStalwartCredentials(request);
+    if (!creds) {
+      return NextResponse.json({ error: 'Not authenticated' }, { status: 401 });
+    }
+
+    const sessionRes = await fetch(`${creds.serverUrl}/.well-known/jmap`, {
+      headers: { Authorization: creds.authHeader },
+    });
+    if (!sessionRes.ok) {
+      return NextResponse.json({ error: 'JMAP session failed' }, { status: 502 });
+    }
+    const session = (await sessionRes.json()) as {
+      apiUrl?: string;
+      primaryAccounts?: Record<string, string>;
+    };
+    const apiUrl = session.apiUrl;
+    const accountId = session.primaryAccounts?.['urn:ietf:params:jmap:mail'];
+    if (!apiUrl || !accountId) {
+      return NextResponse.json({ error: 'Incomplete JMAP session' }, { status: 502 });
+    }
+
+    // Find the inbox, then pull the most recent unread message in it. We use
+    // a single batched JMAP request with back-references so this round-trip
+    // is one POST regardless of how many messages exist.
+    const requestBody = {
+      using: ['urn:ietf:params:jmap:core', 'urn:ietf:params:jmap:mail'],
+      methodCalls: [
+        [
+          'Mailbox/query',
+          { accountId, filter: { role: 'inbox' }, limit: 1 },
+          'mb',
+        ],
+        [
+          'Email/query',
+          {
+            accountId,
+            filter: {
+              operator: 'AND',
+              conditions: [
+                { inMailbox: { resultOf: 'mb', name: 'Mailbox/query', path: '/ids/0' } },
+                { notKeyword: '$seen' },
+              ],
+            },
+            sort: [{ property: 'receivedAt', isAscending: false }],
+            limit: 1,
+            calculateTotal: true,
+          },
+          'eq',
+        ],
+        [
+          'Email/get',
+          {
+            accountId,
+            '#ids': { resultOf: 'eq', name: 'Email/query', path: '/ids' },
+            properties: ['id', 'threadId', 'from', 'subject', 'preview', 'receivedAt'],
+          },
+          'eg',
+        ],
+      ],
+    };
+
+    const jmapRes = await fetch(apiUrl, {
+      method: 'POST',
+      headers: {
+        Authorization: creds.authHeader,
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify(requestBody),
+    });
+    if (!jmapRes.ok) {
+      return NextResponse.json({ error: 'JMAP request failed' }, { status: 502 });
+    }
+    const data = (await jmapRes.json()) as {
+      methodResponses: [string, Record<string, unknown>, string][];
+    };
+
+    type EmailLite = {
+      id: string;
+      threadId: string;
+      from?: { name?: string | null; email?: string }[] | null;
+      subject?: string | null;
+      preview?: string | null;
+      receivedAt?: string | null;
+    };
+
+    let email: EmailLite | null = null;
+    let unreadTotal = 0;
+    for (const [method, body] of data.methodResponses) {
+      if (method === 'Email/query') {
+        unreadTotal = ((body as { total?: number }).total) ?? 0;
+      }
+      if (method === 'Email/get') {
+        const list = (body as { list?: EmailLite[] }).list ?? [];
+        email = list[0] ?? null;
+      }
+    }
+
+    return NextResponse.json({
+      email,
+      unreadTotal,
+    }, {
+      headers: {
+        // SW already gates on its own logic - don't let push events get
+        // cached and served stale.
+        'Cache-Control': 'no-store',
+      },
+    });
+  } catch (error) {
+    // `fetch failed` from undici is too generic to debug — the real reason
+    // (ENOTFOUND, ECONNREFUSED, TLS error, …) is on `error.cause`.
+    const err = error as Error & { cause?: { code?: string; message?: string } };
+    logger.error('push preview failed', {
+      error: err?.message ?? 'Unknown error',
+      causeCode: err?.cause?.code,
+      causeMessage: err?.cause?.message,
+    });
+    return NextResponse.json({ error: 'Internal error' }, { status: 500 });
+  }
+}

app/globals.css

@@ -204,6 +204,31 @@ body {
   min-width: 100%;
 }
 
+/* Forces light-theme CSS variables inside the email content area, so when
+   "Always Show Emails in Light Mode" is enabled in dark theme the surrounding
+   sender info / attachments / plain-text body don't end up with light text
+   on a white background. */
+.email-content-light {
+  --color-background: #ffffff;
+  --color-foreground: #0f172a;
+  --color-muted: #f1f5f9;
+  --color-muted-foreground: #64748b;
+  --color-border: #e2e8f0;
+  --color-card: #ffffff;
+  --color-card-foreground: #0f172a;
+  --color-popover: #ffffff;
+  --color-popover-foreground: #0f172a;
+  --color-secondary: #f8fafc;
+  --color-secondary-foreground: #0f172a;
+  --color-accent: #dbeafe;
+  --color-accent-foreground: #1e40af;
+  --color-input: #e2e8f0;
+}
+
+.email-content-light .email-content-text a {
+  color: #2563eb;
+}
+
 .email-content-text {
   padding: 1rem 1.25rem;
 }
@@ -680,3 +705,54 @@ body {
 .tiptap .ProseMirror-selectednode img {
   outline: none;
 }
+
+.tiptap table {
+  border-collapse: collapse;
+  margin: 0.5rem 0;
+  table-layout: fixed;
+  width: 100%;
+  overflow: hidden;
+}
+
+.tiptap table td,
+.tiptap table th {
+  border: 1px solid var(--color-border);
+  padding: 0.375rem 0.5rem;
+  vertical-align: top;
+  position: relative;
+  min-width: 1em;
+}
+
+.tiptap table th {
+  background-color: var(--color-muted) !important;
+  color: var(--color-foreground) !important;
+  font-weight: 600;
+  text-align: left;
+}
+
+.tiptap table p {
+  margin: 0;
+}
+
+.tiptap table .selectedCell::after {
+  background: rgba(99, 102, 241, 0.15);
+  content: "";
+  inset: 0;
+  pointer-events: none;
+  position: absolute;
+  z-index: 2;
+}
+
+.tiptap table .column-resize-handle {
+  background-color: var(--color-primary);
+  bottom: -2px;
+  pointer-events: none;
+  position: absolute;
+  right: -2px;
+  top: 0;
+  width: 4px;
+}
+
+.tiptap.resize-cursor {
+  cursor: col-resize;
+}

components/calendar/calendar-day-view.tsx

@@ -20,6 +20,7 @@ interface CalendarDayViewProps {
   onHoverEvent?: (event: CalendarEvent, anchorRect: DOMRect) => void;
   onHoverLeave?: () => void;
   onContextMenuEvent?: (e: React.MouseEvent, event: CalendarEvent) => void;
+  onContextMenuEmpty?: (e: React.MouseEvent, date: Date, hour?: number, allDayArea?: boolean) => void;
   onCreateAtTime: (date: Date, endDate?: Date) => void;
   timeFormat?: "12h" | "24h";
   isMobile?: boolean;
@@ -39,6 +40,7 @@ export function CalendarDayView({
   onHoverEvent,
   onHoverLeave,
   onContextMenuEvent,
+  onContextMenuEmpty,
   onCreateAtTime,
   timeFormat = "24h",
   isMobile,
@@ -144,7 +146,13 @@ export function CalendarDayView({
       </div>
 
       {(allDayEvents.length > 0 || dayTasks.length > 0) && (
-        <div className="px-4 py-2 border-b border-border">
+        <div
+          className="px-4 py-2 border-b border-border"
+          onContextMenu={onContextMenuEmpty ? (e) => {
+            if ((e.target as HTMLElement).closest("[data-calendar-event],button")) return;
+            onContextMenuEmpty(e, selectedDate, undefined, true);
+          } : undefined}
+        >
           {allDayEvents.length > 0 && (
             <>
               <div className="text-[10px] text-muted-foreground mb-1">{t("events.all_day")}</div>
@@ -240,6 +248,7 @@ export function CalendarDayView({
                 aria-label={formatHour(h)}
                 onClick={() => handleSlotClick(selectedDate, h)}
                 onDoubleClick={() => handleSlotDoubleClick(selectedDate, h)}
+                onContextMenu={onContextMenuEmpty ? (e) => onContextMenuEmpty(e, selectedDate, h, false) : undefined}
                 className="border-b border-border/50 hover:bg-muted/30 cursor-pointer transition-colors"
                 style={{ height: HOUR_HEIGHT }}
               />

components/calendar/calendar-month-view.tsx

@@ -24,6 +24,7 @@ interface CalendarMonthViewProps {
   onHoverEvent?: (event: CalendarEvent, anchorRect: DOMRect) => void;
   onHoverLeave?: () => void;
   onContextMenuEvent?: (e: React.MouseEvent, event: CalendarEvent) => void;
+  onContextMenuEmpty?: (e: React.MouseEvent, date: Date, hour?: number, allDayArea?: boolean) => void;
   onCreateAtTime?: (date: Date) => void;
   firstDayOfWeek?: number;
   isMobile?: boolean;
@@ -39,6 +40,7 @@ export function CalendarMonthView({
   onHoverEvent,
   onHoverLeave,
   onContextMenuEvent,
+  onContextMenuEmpty,
   onCreateAtTime,
   firstDayOfWeek = 1,
   isMobile,
@@ -174,6 +176,7 @@ export function CalendarMonthView({
                   aria-label={fullDateLabel}
                   onClick={() => onSelectDate(day)}
                   onDoubleClick={() => onCreateAtTime?.(day)}
+                  onContextMenu={onContextMenuEmpty ? (e) => onContextMenuEmpty(e, day, undefined, true) : undefined}
                   onDragOver={(e) => handleCellDragOver(e, key)}
                   onDragLeave={handleCellDragLeave}
                   onDrop={(e) => handleCellDrop(e, day)}

components/calendar/calendar-sidebar-panel.tsx

@@ -1,8 +1,8 @@
 "use client";
 
-import { useState, useRef, useEffect, useMemo } from "react";
+import { useMemo, useState } from "react";
 import { useTranslations } from "next-intl";
-import { Globe, ListTodo, Pencil, RefreshCw, Share2, Trash2, Cake } from "lucide-react";
+import { Globe, ListTodo, Pencil, RefreshCw, Share2, Trash2, Cake, Users, Plus, Eraser, Palette } from "lucide-react";
 import { cn, formatDateTime } from "@/lib/utils";
 import type { Calendar } from "@/lib/jmap/types";
 import { CalendarColorPicker } from "@/components/settings/calendar-management-settings";
@@ -11,6 +11,8 @@ import { useSettingsStore } from "@/stores/settings-store";
 import { useTaskStore } from "@/stores/task-store";
 import { BIRTHDAY_CALENDAR_ID } from "@/lib/birthday-calendar";
 import { toast } from "@/stores/toast-store";
+import { ContextMenu, ContextMenuItem, ContextMenuSeparator, ContextMenuSubMenu } from "@/components/ui/context-menu";
+import { useContextMenu } from "@/hooks/use-context-menu";
 import type { IJMAPClient } from '@/lib/jmap/client-interface';
 
 interface CalendarSidebarPanelProps {
@@ -18,6 +20,11 @@ interface CalendarSidebarPanelProps {
   selectedCalendarIds: string[];
   onToggleVisibility: (id: string) => void;
   onColorChange?: (calendarId: string, color: string) => void;
+  onShareCalendar?: (calendar: Calendar) => void;
+  onCreateEvent?: (calendar: Calendar) => void;
+  onClearCalendar?: (calendar: Calendar) => void;
+  onDeleteCalendar?: (calendar: Calendar) => void;
+  onCreateCalendar?: () => void;
   onSubscribe?: () => void;
   onEditSubscription?: (subscriptionId: string) => void;
   client?: IJMAPClient | null;
@@ -28,12 +35,18 @@ export function CalendarSidebarPanel({
   selectedCalendarIds,
   onToggleVisibility,
   onColorChange,
+  onShareCalendar,
+  onCreateEvent,
+  onClearCalendar,
+  onDeleteCalendar,
+  onCreateCalendar,
   onSubscribe,
   onEditSubscription,
   client,
 }: CalendarSidebarPanelProps) {
   const t = useTranslations("calendar");
   const tSub = useTranslations("calendar.subscription");
+  const tMgmt = useTranslations("calendar.management");
   const isSubscriptionCalendar = useCalendarStore((s) => s.isSubscriptionCalendar);
   const icalSubscriptions = useCalendarStore((s) => s.icalSubscriptions);
   const refreshICalSubscription = useCalendarStore((s) => s.refreshICalSubscription);
@@ -49,11 +62,8 @@ export function CalendarSidebarPanel({
     return tasks.filter(t => t.progress !== 'completed' && t.progress !== 'cancelled' && t.due && new Date(t.due) < now).length;
   }, [tasks]);
 
-  const [colorPickerId, setColorPickerId] = useState<string | null>(null);
-  const [contextMenuCalId, setContextMenuCalId] = useState<string | null>(null);
+  const { contextMenu, openContextMenu, closeContextMenu, menuRef } = useContextMenu<Calendar>();
   const [refreshingSubId, setRefreshingSubId] = useState<string | null>(null);
-  const colorPickerRef = useRef<HTMLDivElement>(null);
-  const contextMenuRef = useRef<HTMLDivElement>(null);
 
   const personalCalendars = useMemo(() => calendars.filter(c => !c.isShared), [calendars]);
   const sharedAccountGroups = useMemo(() => {
@@ -69,30 +79,6 @@ export function CalendarSidebarPanel({
     return Array.from(groups.values());
   }, [calendars]);
 
-  useEffect(() => {
-    if (!colorPickerId && !contextMenuCalId) return;
-    const handleClick = (e: MouseEvent) => {
-      if (colorPickerRef.current && !colorPickerRef.current.contains(e.target as Node)) {
-        setColorPickerId(null);
-      }
-      if (contextMenuRef.current && !contextMenuRef.current.contains(e.target as Node)) {
-        setContextMenuCalId(null);
-      }
-    };
-    const handleKey = (e: KeyboardEvent) => {
-      if (e.key === 'Escape') {
-        setColorPickerId(null);
-        setContextMenuCalId(null);
-      }
-    };
-    document.addEventListener('mousedown', handleClick);
-    document.addEventListener('keydown', handleKey);
-    return () => {
-      document.removeEventListener('mousedown', handleClick);
-      document.removeEventListener('keydown', handleKey);
-    };
-  }, [colorPickerId, contextMenuCalId]);
-
   const getSubscriptionForCalendar = (calendarId: string) => {
     return icalSubscriptions.find(s => s.calendarId === calendarId);
   };
@@ -100,7 +86,6 @@ export function CalendarSidebarPanel({
   const handleRefreshSubscription = async (subId: string) => {
     if (!client) return;
     setRefreshingSubId(subId);
-    setContextMenuCalId(null);
     try {
       await refreshICalSubscription(client, subId);
       toast.success(tSub('refresh_success'));
@@ -113,7 +98,6 @@ export function CalendarSidebarPanel({
 
   const handleUnsubscribe = async (subId: string) => {
     if (!client) return;
-    setContextMenuCalId(null);
     try {
       await removeICalSubscription(client, subId);
       toast.success(tSub('deleted'));
@@ -127,21 +111,13 @@ export function CalendarSidebarPanel({
   const renderCalendarItem = (cal: Calendar) => {
     const isVisible = selectedCalendarIds.includes(cal.id);
     const color = cal.color || "#3b82f6";
+    const hasMenu = isSubscriptionCalendar(cal.id) ? !!client : true;
 
     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);
-            }
-          }}
+          onContextMenu={hasMenu ? (e) => openContextMenu(e, cal) : undefined}
           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"
@@ -169,70 +145,101 @@ export function CalendarSidebarPanel({
             <Cake className="w-3 h-3 text-muted-foreground flex-shrink-0" />
           )}
         </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={() => {
-                  setContextMenuCalId(null);
-                  onEditSubscription?.(sub.id);
-                }}
-                className="flex items-center gap-2 w-full px-3 py-1.5 text-sm hover:bg-muted transition-colors"
-              >
-                <Pencil className="w-3.5 h-3.5" />
-                {tSub('edit')}
-              </button>
-              <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>
     );
   };
 
+  const renderCalendarMenu = () => {
+    const cal = contextMenu.data;
+    if (!cal) return null;
+
+    if (isSubscriptionCalendar(cal.id)) {
+      const sub = getSubscriptionForCalendar(cal.id);
+      if (!sub || !client) return null;
+      return (
+        <ContextMenu ref={menuRef} isOpen={contextMenu.isOpen} position={contextMenu.position} onClose={closeContextMenu}>
+          <ContextMenuItem
+            icon={Pencil}
+            label={tSub('edit')}
+            onClick={() => { closeContextMenu(); onEditSubscription?.(sub.id); }}
+          />
+          <ContextMenuItem
+            icon={RefreshCw}
+            label={tSub('refresh')}
+            onClick={() => { closeContextMenu(); handleRefreshSubscription(sub.id); }}
+          />
+          <ContextMenuSeparator />
+          <ContextMenuItem
+            icon={Trash2}
+            label={tSub('unsubscribe')}
+            onClick={() => { closeContextMenu(); handleUnsubscribe(sub.id); }}
+            destructive
+          />
+          {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>
+          )}
+        </ContextMenu>
+      );
+    }
+
+    const isBirthday = cal.id === BIRTHDAY_CALENDAR_ID;
+    const canCreate = onCreateEvent && !isBirthday && cal.myRights?.mayWriteOwn !== false;
+    const canShare = onShareCalendar && cal.myRights?.mayShare && !cal.isShared;
+    const canChangeColor = !!onColorChange;
+    const canClear = onClearCalendar && !isBirthday && cal.myRights?.mayDelete !== false;
+    const canDelete = onDeleteCalendar && !isBirthday && !cal.isDefault && !cal.isShared;
+    const showSeparator = (canCreate || canShare || canChangeColor) && (canClear || canDelete);
+    const color = cal.color || "#3b82f6";
+
+    return (
+      <ContextMenu ref={menuRef} isOpen={contextMenu.isOpen} position={contextMenu.position} onClose={closeContextMenu}>
+        {canCreate && (
+          <ContextMenuItem
+            icon={Plus}
+            label={tMgmt('new_event_in_calendar')}
+            onClick={() => { closeContextMenu(); onCreateEvent(cal); }}
+          />
+        )}
+        {canShare && (
+          <ContextMenuItem
+            icon={Users}
+            label={tMgmt('share')}
+            onClick={() => { closeContextMenu(); onShareCalendar(cal); }}
+          />
+        )}
+        {canChangeColor && (
+          <ContextMenuSubMenu icon={Palette} label={tMgmt('change_color')}>
+            <div className="px-2 py-1.5 w-[200px]">
+              <CalendarColorPicker
+                value={color}
+                onChange={(c) => { onColorChange(cal.id, c); closeContextMenu(); }}
+                allowCustom
+              />
+            </div>
+          </ContextMenuSubMenu>
+        )}
+        {showSeparator && <ContextMenuSeparator />}
+        {canClear && (
+          <ContextMenuItem
+            icon={Eraser}
+            label={tMgmt('clear_events')}
+            onClick={() => { closeContextMenu(); onClearCalendar(cal); }}
+          />
+        )}
+        {canDelete && (
+          <ContextMenuItem
+            icon={Trash2}
+            label={tMgmt('delete')}
+            onClick={() => { closeContextMenu(); onDeleteCalendar(cal); }}
+            destructive
+          />
+        )}
+      </ContextMenu>
+    );
+  };
+
   return (
     <div className="mt-4">
       {enableCalendarTasks && (
@@ -250,9 +257,22 @@ export function CalendarSidebarPanel({
           )}
         </button>
       )}
-      <h3 className="text-xs font-medium text-muted-foreground uppercase tracking-wider mb-2 px-1">
-        {t("my_calendars")}
-      </h3>
+      <div className="flex items-center justify-between mb-2 px-1 group">
+        {onCreateCalendar ? (
+          <button
+            onClick={onCreateCalendar}
+            className="text-xs font-medium text-muted-foreground uppercase tracking-wider hover:text-foreground transition-colors flex items-center gap-1.5"
+            title={tMgmt('add_calendar')}
+          >
+            {t('my_calendars')}
+            <Plus className="w-3 h-3 opacity-0 group-hover:opacity-100 transition-opacity" />
+          </button>
+        ) : (
+          <h3 className="text-xs font-medium text-muted-foreground uppercase tracking-wider">
+            {t('my_calendars')}
+          </h3>
+        )}
+      </div>
       <div className="space-y-0.5">
         {personalCalendars.map(renderCalendarItem)}
       </div>
@@ -268,6 +288,8 @@ export function CalendarSidebarPanel({
           </div>
         </div>
       ))}
+
+      {renderCalendarMenu()}
     </div>
   );
 }

components/calendar/calendar-week-view.tsx

@@ -23,6 +23,7 @@ interface CalendarWeekViewProps {
   onHoverEvent?: (event: CalendarEvent, anchorRect: DOMRect) => void;
   onHoverLeave?: () => void;
   onContextMenuEvent?: (e: React.MouseEvent, event: CalendarEvent) => void;
+  onContextMenuEmpty?: (e: React.MouseEvent, date: Date, hour?: number, allDayArea?: boolean) => void;
   onCreateAtTime: (date: Date, endDate?: Date) => void;
   firstDayOfWeek?: number;
   timeFormat?: "12h" | "24h";
@@ -44,6 +45,7 @@ export function CalendarWeekView({
   onHoverEvent,
   onHoverLeave,
   onContextMenuEvent,
+  onContextMenuEmpty,
   onCreateAtTime,
   firstDayOfWeek = 1,
   timeFormat = "24h",
@@ -219,7 +221,11 @@ export function CalendarWeekView({
             style={{ minHeight: Math.max(28, (allDayRowCount + taskRowCount) * 24 + 4) }}
           >
             {weekDays.map((day) => (
-              <div key={format(day, "yyyy-MM-dd")} className="bg-background min-h-[28px]" />
+              <div
+                key={format(day, "yyyy-MM-dd")}
+                className="bg-background min-h-[28px]"
+                onContextMenu={onContextMenuEmpty ? (e) => onContextMenuEmpty(e, day, undefined, true) : undefined}
+              />
             ))}
 
             <div className="absolute inset-0 pointer-events-none">
@@ -378,6 +384,7 @@ export function CalendarWeekView({
                       aria-label={`${intlFormatter.dateTime(day, { weekday: "short" })} ${formatHour(h)}`}
                       onClick={() => handleSlotClick(day, h)}
                       onDoubleClick={() => handleSlotDoubleClick(day, h)}
+                      onContextMenu={onContextMenuEmpty ? (e) => onContextMenuEmpty(e, day, h, false) : undefined}
                       className="border-b border-border/50 hover:bg-muted/30 cursor-pointer transition-colors"
                       style={{ height: HOUR_HEIGHT }}
                     />

components/calendar/create-calendar-modal.tsx

@@ -0,0 +1,151 @@
+"use client";
+
+import { useCallback, useEffect, useRef, useState } from "react";
+import { useTranslations } from "next-intl";
+import { Button } from "@/components/ui/button";
+import { X, Loader2, Calendar as CalendarIcon } from "lucide-react";
+import type { IJMAPClient } from "@/lib/jmap/client-interface";
+import { useCalendarStore } from "@/stores/calendar-store";
+import { CalendarColorPicker } from "@/components/settings/calendar-management-settings";
+import { toast } from "@/stores/toast-store";
+
+interface CreateCalendarModalProps {
+  client: IJMAPClient;
+  onClose: () => void;
+}
+
+export function CreateCalendarModal({ client, onClose }: CreateCalendarModalProps) {
+  const t = useTranslations("calendar.management");
+  const tCommon = useTranslations("common");
+  const createCalendar = useCalendarStore((s) => s.createCalendar);
+
+  const [name, setName] = useState("");
+  const [color, setColor] = useState("#3b82f6");
+  const [isSubmitting, setIsSubmitting] = useState(false);
+  const modalRef = useRef<HTMLDivElement>(null);
+
+  const isValid = name.trim().length > 0;
+
+  const handleSubmit = useCallback(async () => {
+    const trimmed = name.trim();
+    if (!trimmed) return;
+    setIsSubmitting(true);
+    try {
+      const created = await createCalendar(client, { name: trimmed, color });
+      if (created) {
+        toast.success(t("calendar_created"));
+        onClose();
+      } else {
+        toast.error(t("error_create"));
+      }
+    } catch {
+      toast.error(t("error_create"));
+    } finally {
+      setIsSubmitting(false);
+    }
+  }, [name, color, client, createCalendar, onClose, t]);
+
+  useEffect(() => {
+    const handleKey = (e: KeyboardEvent) => {
+      if (e.key === "Escape" && !isSubmitting) onClose();
+    };
+    window.addEventListener("keydown", handleKey);
+    return () => window.removeEventListener("keydown", handleKey);
+  }, [onClose, isSubmitting]);
+
+  useEffect(() => {
+    const modal = modalRef.current;
+    if (!modal) return;
+    const focusableEls = modal.querySelectorAll<HTMLElement>(
+      'input, select, textarea, button, [tabindex]:not([tabindex="-1"])'
+    );
+    const firstEl = focusableEls[0];
+    const lastEl = focusableEls[focusableEls.length - 1];
+
+    const handler = (e: KeyboardEvent) => {
+      if (e.key !== "Tab") return;
+      if (e.shiftKey && document.activeElement === firstEl) {
+        e.preventDefault();
+        lastEl?.focus();
+      } else if (!e.shiftKey && document.activeElement === lastEl) {
+        e.preventDefault();
+        firstEl?.focus();
+      }
+    };
+    modal.addEventListener("keydown", handler);
+    firstEl?.focus();
+    return () => modal.removeEventListener("keydown", handler);
+  }, []);
+
+  return (
+    <div className="fixed inset-0 z-50 flex items-center justify-center">
+      <div
+        className="absolute inset-0 bg-black/50 backdrop-blur-[1px]"
+        onClick={() => !isSubmitting && onClose()}
+        aria-hidden="true"
+      />
+      <div
+        ref={modalRef}
+        role="dialog"
+        aria-modal="true"
+        aria-label={t("add_calendar")}
+        className="relative bg-background border border-border rounded-lg shadow-xl w-full max-w-md mx-4 animate-in zoom-in-95 duration-200"
+      >
+        <div className="flex items-center justify-between px-6 py-4 border-b border-border">
+          <div className="flex items-center gap-2">
+            <CalendarIcon className="w-5 h-5 text-primary" />
+            <h2 className="text-lg font-semibold">{t("add_calendar")}</h2>
+          </div>
+          <button
+            onClick={onClose}
+            disabled={isSubmitting}
+            className="p-1.5 rounded-md hover:bg-muted transition-colors duration-150 text-muted-foreground hover:text-foreground disabled:opacity-50"
+            aria-label={tCommon("close")}
+          >
+            <X className="w-5 h-5" />
+          </button>
+        </div>
+
+        <div className="px-6 py-4 space-y-4">
+          <div>
+            <label className="text-xs font-medium text-muted-foreground mb-1 block">
+              {t("name")}
+            </label>
+            <input
+              type="text"
+              value={name}
+              onChange={(e) => setName(e.target.value)}
+              placeholder={t("name_placeholder")}
+              className="w-full rounded-md border border-input bg-background px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-ring"
+              disabled={isSubmitting}
+              onKeyDown={(e) => { if (e.key === "Enter" && isValid) handleSubmit(); }}
+            />
+          </div>
+
+          <div>
+            <label className="text-xs font-medium text-muted-foreground mb-1 block">
+              {t("color")}
+            </label>
+            <CalendarColorPicker value={color} onChange={setColor} allowCustom />
+          </div>
+        </div>
+
+        <div className="flex items-center justify-end gap-2 px-6 py-4 border-t border-border">
+          <Button variant="outline" onClick={onClose} disabled={isSubmitting}>
+            {tCommon("cancel")}
+          </Button>
+          <Button onClick={handleSubmit} disabled={!isValid || isSubmitting}>
+            {isSubmitting ? (
+              <>
+                <Loader2 className="w-4 h-4 animate-spin mr-2" />
+                {tCommon("loading")}
+              </>
+            ) : (
+              t("create")
+            )}
+          </Button>
+        </div>
+      </div>
+    </div>
+  );
+}

components/calendar/empty-space-context-menu.tsx

@@ -0,0 +1,67 @@
+"use client";
+
+import { useTranslations } from "next-intl";
+import {
+  ContextMenu,
+  ContextMenuItem,
+  ContextMenuSeparator,
+} from "@/components/ui/context-menu";
+import { Plus, CalendarDays, CheckSquare, Clock } from "lucide-react";
+
+interface Position {
+  x: number;
+  y: number;
+}
+
+interface EmptySpaceContextMenuProps {
+  position: Position;
+  isOpen: boolean;
+  onClose: () => void;
+  menuRef: React.RefObject<HTMLDivElement | null>;
+  onNewEvent: () => void;
+  onNewAllDayEvent: () => void;
+  onNewTask?: () => void;
+  onGoToToday: () => void;
+  showAllDayOption?: boolean;
+}
+
+export function EmptySpaceContextMenu({
+  position,
+  isOpen,
+  onClose,
+  menuRef,
+  onNewEvent,
+  onNewAllDayEvent,
+  onNewTask,
+  onGoToToday,
+  showAllDayOption = true,
+}: EmptySpaceContextMenuProps) {
+  const t = useTranslations("calendar");
+
+  const handle = (fn: () => void) => () => {
+    fn();
+    onClose();
+  };
+
+  return (
+    <ContextMenu ref={menuRef} isOpen={isOpen} position={position} onClose={onClose}>
+      <ContextMenuItem icon={Plus} label={t("events.new_event")} onClick={handle(onNewEvent)} />
+      {showAllDayOption && (
+        <ContextMenuItem
+          icon={CalendarDays}
+          label={t("events.new_all_day_event")}
+          onClick={handle(onNewAllDayEvent)}
+        />
+      )}
+      {onNewTask && (
+        <ContextMenuItem
+          icon={CheckSquare}
+          label={t("events.new_task")}
+          onClick={handle(onNewTask)}
+        />
+      )}
+      <ContextMenuSeparator />
+      <ContextMenuItem icon={Clock} label={t("events.go_to_today")} onClick={handle(onGoToToday)} />
+    </ContextMenu>
+  );
+}

components/calendar/event-detail-popover.tsx

@@ -19,6 +19,7 @@ import {
   getUserStatus,
   getParticipantList,
 } from "@/lib/calendar-participants";
+import { useFormatEventDate } from "@/hooks/use-format-event-date";
 
 interface EventDetailPopoverProps {
   event: CalendarEvent;
@@ -253,6 +254,8 @@ export function EventDetailPopover({
 
   const hasParticipants = participants.length > 0;
 
+  const formatEventDate = useFormatEventDate();
+
   const popover = (
     <div
       ref={popoverRef}
@@ -329,7 +332,7 @@ export function EventDetailPopover({
           <Clock className="w-4 h-4 text-muted-foreground mt-0.5 flex-shrink-0" />
           <div className="text-sm">
             <span className="font-medium text-foreground">
-              {format(startDate, "EEE, MMM d, yyyy")}
+              {formatEventDate(startDate)}
             </span>
             {event.showWithoutTime ? (
               <span className="text-muted-foreground ml-1.5">{t("events.all_day")}</span>

components/calendar/event-modal.tsx

@@ -21,6 +21,7 @@ import {
 import { PluginSlot } from "@/components/plugins/plugin-slot";
 import { useSettingsStore } from "@/stores/settings-store";
 import { generateUUID } from "@/lib/utils";
+import { useFormatEventDate } from "@/hooks/use-format-event-date";
 
 export interface PendingEventPreview {
   start: Date;
@@ -35,6 +36,8 @@ interface EventModalProps {
   calendars: Calendar[];
   defaultDate?: Date;
   defaultEndDate?: Date;
+  defaultAllDay?: boolean;
+  defaultCalendarId?: string;
   onSave: (data: Partial<CalendarEvent>, sendSchedulingMessages?: boolean) => void | Promise<void>;
   onDelete?: (id: string, sendSchedulingMessages?: boolean) => void;
   onDuplicate?: (data: Partial<CalendarEvent>) => void;
@@ -113,6 +116,8 @@ export function EventModal({
   calendars,
   defaultDate,
   defaultEndDate,
+  defaultAllDay,
+  defaultCalendarId,
   onSave,
   onDelete,
   onDuplicate,
@@ -126,6 +131,7 @@ export function EventModal({
   const timeFormat = useSettingsStore((s) => s.timeFormat);
   const timeDisplayFmt = timeFormat === "12h" ? "h:mm a" : "HH:mm";
   const isEdit = !!event;
+  const formatEventDate = useFormatEventDate();
   const [mode, setMode] = useState<"view" | "edit">(isEdit ? "view" : "edit");
 
   const userIsOrganizer = useMemo(() => {
@@ -197,9 +203,10 @@ export function EventModal({
   const [startTime, setStartTime] = useState(formatTimeInput(getInitialStart()));
   const [endDate, setEndDate] = useState(formatDateInput(getInitialEnd()));
   const [endTime, setEndTime] = useState(formatTimeInput(getInitialEnd()));
-  const [allDay, setAllDay] = useState(event?.showWithoutTime || false);
+  const [allDay, setAllDay] = useState(event?.showWithoutTime || defaultAllDay || false);
   const [calendarId, setCalendarId] = useState<string>(() => {
     if (event?.calendarIds) return getPrimaryCalendarId(event) || calendars[0]?.id || "";
+    if (defaultCalendarId && calendars.some(c => c.id === defaultCalendarId)) return defaultCalendarId;
     const defaultCal = calendars.find(c => c.isDefault);
     return defaultCal?.id || calendars[0]?.id || "";
   });
@@ -490,14 +497,14 @@ export function EventModal({
 
     return (
       <div ref={modalRef} role="dialog" aria-modal={isMobile || undefined} aria-label={event.title || t("events.no_title")} className={isMobile ? "fixed inset-0 z-50 flex flex-col bg-background" : "flex flex-col h-full bg-background"}>
-          <div className="flex items-center justify-between px-6 py-4 border-b border-border flex-shrink-0">
-            <h2 className="text-lg font-semibold truncate">{event.title || t("events.no_title")}</h2>
-            <button onClick={onClose} className="p-1.5 rounded-md hover:bg-muted transition-colors duration-150 text-muted-foreground hover:text-foreground" aria-label={t("form.cancel")}>
-              <X className="w-5 h-5" />
-            </button>
-          </div>
+        <div className="flex items-center justify-between px-6 py-4 border-b border-border flex-shrink-0">
+          <h2 className="text-lg font-semibold truncate">{event.title || t("events.no_title")}</h2>
+          <button onClick={onClose} className="p-1.5 rounded-md hover:bg-muted transition-colors duration-150 text-muted-foreground hover:text-foreground" aria-label={t("form.cancel")}>
+            <X className="w-5 h-5" />
+          </button>
+        </div>
 
-          <div className="flex-1 overflow-y-auto">
+        <div className="flex-1 overflow-y-auto">
           <div className="px-6 py-4 space-y-3">
             <div className="flex items-start gap-3 rounded-lg border border-blue-200 dark:border-blue-800 bg-blue-50 dark:bg-blue-950/50 px-4 py-3">
               <CalendarDays className="w-5 h-5 text-blue-600 dark:text-blue-400 mt-0.5 flex-shrink-0" />
@@ -512,7 +519,7 @@ export function EventModal({
             </div>
 
             <div className="text-sm">
-              <span className="font-medium">{format(startD, "EEE, MMM d, yyyy")}</span>
+              <span className="font-medium">{formatEventDate(startD)}</span>
               {!event.showWithoutTime && (
                 <span className="text-muted-foreground ml-2">
                   {format(startD, timeDisplayFmt)} – {format(endD, timeDisplayFmt)}
@@ -545,48 +552,48 @@ export function EventModal({
               </div>
             )}
           </div>
-          </div>
+        </div>
 
-          <div className="px-6 py-4 border-t border-border flex-shrink-0">
-            <div className="flex items-center justify-between">
-              <span className="text-sm font-medium">{t("participants.rsvp_label")}</span>
-              <div className="flex gap-2">
-                <Button
-                  size="sm"
-                  variant={userCurrentStatus === "accepted" ? "default" : "outline"}
-                  onClick={() => handleRsvp("accepted")}
-                  className={userCurrentStatus === "accepted"
-                    ? "bg-success hover:bg-success/80 text-success-foreground"
-                    : "text-success border-success/30 hover:bg-success/10"}
-                >
-                  {userCurrentStatus === "accepted" && <Check className="w-4 h-4 mr-1" />}
-                  {t("participants.accepted")}
-                </Button>
-                <Button
-                  size="sm"
-                  variant={userCurrentStatus === "tentative" ? "default" : "outline"}
-                  onClick={() => handleRsvp("tentative")}
-                  className={userCurrentStatus === "tentative"
-                    ? "bg-warning hover:bg-warning/80 text-warning-foreground"
-                    : "border border-warning/30 text-warning hover:bg-warning/10"}
-                >
-                  {userCurrentStatus === "tentative" && <Check className="w-4 h-4 mr-1" />}
-                  {t("participants.tentative")}
-                </Button>
-                <Button
-                  size="sm"
-                  variant={userCurrentStatus === "declined" ? "default" : "ghost"}
-                  onClick={() => handleRsvp("declined")}
-                  className={userCurrentStatus === "declined"
-                    ? "bg-destructive hover:bg-destructive/80 text-destructive-foreground"
-                    : "text-destructive hover:bg-destructive/10"}
-                >
-                  {userCurrentStatus === "declined" && <Check className="w-4 h-4 mr-1" />}
-                  {t("participants.declined")}
-                </Button>
-              </div>
+        <div className="px-6 py-4 border-t border-border flex-shrink-0">
+          <div className="flex items-center justify-between">
+            <span className="text-sm font-medium">{t("participants.rsvp_label")}</span>
+            <div className="flex gap-2">
+              <Button
+                size="sm"
+                variant={userCurrentStatus === "accepted" ? "default" : "outline"}
+                onClick={() => handleRsvp("accepted")}
+                className={userCurrentStatus === "accepted"
+                  ? "bg-success hover:bg-success/80 text-success-foreground"
+                  : "text-success border-success/30 hover:bg-success/10"}
+              >
+                {userCurrentStatus === "accepted" && <Check className="w-4 h-4 mr-1" />}
+                {t("participants.accepted")}
+              </Button>
+              <Button
+                size="sm"
+                variant={userCurrentStatus === "tentative" ? "default" : "outline"}
+                onClick={() => handleRsvp("tentative")}
+                className={userCurrentStatus === "tentative"
+                  ? "bg-warning hover:bg-warning/80 text-warning-foreground"
+                  : "border border-warning/30 text-warning hover:bg-warning/10"}
+              >
+                {userCurrentStatus === "tentative" && <Check className="w-4 h-4 mr-1" />}
+                {t("participants.tentative")}
+              </Button>
+              <Button
+                size="sm"
+                variant={userCurrentStatus === "declined" ? "default" : "ghost"}
+                onClick={() => handleRsvp("declined")}
+                className={userCurrentStatus === "declined"
+                  ? "bg-destructive hover:bg-destructive/80 text-destructive-foreground"
+                  : "text-destructive hover:bg-destructive/10"}
+              >
+                {userCurrentStatus === "declined" && <Check className="w-4 h-4 mr-1" />}
+                {t("participants.declined")}
+              </Button>
             </div>
           </div>
+        </div>
       </div>
     );
   }
@@ -633,7 +640,7 @@ export function EventModal({
               <Clock className="w-4 h-4 text-muted-foreground mt-0.5 flex-shrink-0" />
               <div className="text-sm">
                 <span className="font-medium text-foreground">
-                  {format(startD, "EEE, MMM d, yyyy")}
+                  {formatEventDate(startD)}
                 </span>
                 {event.showWithoutTime ? (
                   <span className="text-muted-foreground ml-1.5">{t("events.all_day")}</span>
@@ -762,16 +769,16 @@ export function EventModal({
 
   return (
     <div ref={modalRef} role="dialog" aria-modal={isMobile || undefined} aria-label={isEdit ? t("events.edit") : t("events.create")} data-tour="event-modal" className={isMobile ? "fixed inset-0 z-50 flex flex-col bg-background" : "flex flex-col h-full bg-background"}>
-        <div className="flex items-center justify-between px-6 py-4 border-b border-border flex-shrink-0">
-          <h2 className="text-lg font-semibold">
-            {isEdit ? t("events.edit") : t("events.create")}
-          </h2>
-          <button onClick={onClose} className="p-1.5 rounded-md hover:bg-muted transition-colors duration-150 text-muted-foreground hover:text-foreground" aria-label={t("form.cancel")}>
-            <X className="w-5 h-5" />
-          </button>
-        </div>
+      <div className="flex items-center justify-between px-6 py-4 border-b border-border flex-shrink-0">
+        <h2 className="text-lg font-semibold">
+          {isEdit ? t("events.edit") : t("events.create")}
+        </h2>
+        <button onClick={onClose} className="p-1.5 rounded-md hover:bg-muted transition-colors duration-150 text-muted-foreground hover:text-foreground" aria-label={t("form.cancel")}>
+          <X className="w-5 h-5" />
+        </button>
+      </div>
 
-        <div className="flex-1 overflow-y-auto">
+      <div className="flex-1 overflow-y-auto">
         <div className="px-6 py-4 space-y-4">
           <div>
             <label className="text-sm font-medium mb-1 block">{t("form.title")}</label>
@@ -981,69 +988,69 @@ export function EventModal({
             </div>
           )}
         </div>
-        </div>
+      </div>
 
-        <div className="flex items-center justify-between px-6 py-4 border-t border-border flex-shrink-0">
-          <div className="flex items-center gap-1">
-            {isEdit && onDelete && (
-              showDeleteConfirm ? (
-                <div className="flex items-center gap-2">
-                  <div>
-                    <span className="text-sm text-red-600 dark:text-red-400">
-                      {t("form.delete_confirm")}
-                    </span>
-                    {hasParticipants && (
-                      <p className="text-xs text-muted-foreground mt-0.5">
-                        {t("participants.cancel_notification")}
-                      </p>
-                    )}
-                  </div>
-                  <Button
-                    variant="outline"
-                    size="sm"
-                    onClick={() => { onDelete(event!.id, hasParticipants || undefined); onClose(); }}
-                    className="text-red-600 dark:text-red-400 border-red-300 dark:border-red-700"
-                  >
-                    {t("events.delete")}
-                  </Button>
-                  <Button variant="ghost" size="sm" onClick={() => setShowDeleteConfirm(false)}>
-                    {t("form.cancel")}
-                  </Button>
+      <div className="flex items-center justify-between px-6 py-4 border-t border-border flex-shrink-0">
+        <div className="flex items-center gap-1">
+          {isEdit && onDelete && (
+            showDeleteConfirm ? (
+              <div className="flex items-center gap-2">
+                <div>
+                  <span className="text-sm text-red-600 dark:text-red-400">
+                    {t("form.delete_confirm")}
+                  </span>
+                  {hasParticipants && (
+                    <p className="text-xs text-muted-foreground mt-0.5">
+                      {t("participants.cancel_notification")}
+                    </p>
+                  )}
                 </div>
-              ) : (
                 <Button
-                  variant="ghost"
+                  variant="outline"
                   size="sm"
-                  onClick={() => setShowDeleteConfirm(true)}
-                  className="text-red-600 dark:text-red-400"
+                  onClick={() => { onDelete(event!.id, hasParticipants || undefined); onClose(); }}
+                  className="text-red-600 dark:text-red-400 border-red-300 dark:border-red-700"
                 >
-                  <Trash2 className="w-4 h-4 mr-1" />
                   {t("events.delete")}
                 </Button>
-              )
-            )}
-            {isEdit && onDuplicate && !showDeleteConfirm && (
+                <Button variant="ghost" size="sm" onClick={() => setShowDeleteConfirm(false)}>
+                  {t("form.cancel")}
+                </Button>
+              </div>
+            ) : (
               <Button
                 variant="ghost"
                 size="sm"
-                onClick={handleDuplicate}
-                aria-label={t("events.duplicate")}
+                onClick={() => setShowDeleteConfirm(true)}
+                className="text-red-600 dark:text-red-400"
               >
-                <Copy className="w-4 h-4 mr-1" />
-                {t("events.duplicate")}
+                <Trash2 className="w-4 h-4 mr-1" />
+                {t("events.delete")}
               </Button>
-            )}
-          </div>
-
-          <div className="flex gap-2">
-            <Button variant="outline" onClick={isEdit ? () => setMode("view") : onClose}>
-              {t("form.cancel")}
+            )
+          )}
+          {isEdit && onDuplicate && !showDeleteConfirm && (
+            <Button
+              variant="ghost"
+              size="sm"
+              onClick={handleDuplicate}
+              aria-label={t("events.duplicate")}
+            >
+              <Copy className="w-4 h-4 mr-1" />
+              {t("events.duplicate")}
             </Button>
-            <Button onClick={handleSave} disabled={!title.trim() || isSaving}>
-              {t("form.save")}
-            </Button>
-          </div>
+          )}
         </div>
+
+        <div className="flex gap-2">
+          <Button variant="outline" onClick={isEdit ? () => setMode("view") : onClose}>
+            {t("form.cancel")}
+          </Button>
+          <Button onClick={handleSave} disabled={!title.trim() || isSaving}>
+            {t("form.save")}
+          </Button>
+        </div>
+      </div>
     </div>
   );
 }

components/contacts/contact-form.tsx

@@ -50,6 +50,7 @@ interface ContactFormProps {
   contact?: ContactCard | null;
   addressBooks?: AddressBook[];
   allKeywords?: string[];
+  defaultAddressBookId?: string;
   onSave: (data: Partial<ContactCard>) => Promise<void>;
   onCancel: () => void;
 }
@@ -143,11 +144,13 @@ function Select({ value, onChange, children, className }: {
   );
 }
 
-export function ContactForm({ contact, addressBooks, allKeywords, onSave, onCancel }: ContactFormProps) {
+export function ContactForm({ contact, addressBooks, allKeywords, defaultAddressBookId, onSave, onCancel }: ContactFormProps) {
   const t = useTranslations("contacts.form");
   const isEditing = !!contact;
 
-  const findComponent = (kind: string) => contact?.name?.components?.find(c => c.kind === kind)?.value || "";
+  // Accept JSContact-standard kinds (RFC 9553) and legacy vCard-style aliases.
+  const findComponent = (...kinds: string[]) =>
+    contact?.name?.components?.find(c => kinds.includes(c.kind))?.value || "";
 
   // Convert RFC 9553 AnniversaryDate to ISO date string for HTML date input
   function anniversaryDateToString(date: AnniversaryDate): string {
@@ -210,11 +213,11 @@ export function ContactForm({ contact, addressBooks, allKeywords, onSave, onCanc
     };
   }
 
-  const [prefix, setPrefix] = useState(findComponent("prefix"));
+  const [prefix, setPrefix] = useState(findComponent("title", "prefix"));
   const [givenName, setGivenName] = useState(findComponent("given"));
-  const [additionalName, setAdditionalName] = useState(findComponent("additional"));
+  const [additionalName, setAdditionalName] = useState(findComponent("given2", "additional", "middle"));
   const [surname, setSurname] = useState(findComponent("surname"));
-  const [suffix, setSuffix] = useState(findComponent("suffix"));
+  const [suffix, setSuffix] = useState(findComponent("generation", "suffix"));
 
   const [nickname, setNickname] = useState(
     contact?.nicknames ? Object.values(contact.nicknames)[0]?.name || "" : ""
@@ -328,8 +331,11 @@ export function ContactForm({ contact, addressBooks, allKeywords, onSave, onCanc
         return ids[0];
       }
     }
+    if (defaultAddressBookId && addressBooks?.some(b => b.id === defaultAddressBookId)) {
+      return defaultAddressBookId;
+    }
     return "";
-  }, [contact]);
+  }, [contact, defaultAddressBookId, addressBooks]);
   const [selectedBookId, setSelectedBookId] = useState(currentBookId);
 
   const initialPhotoEntry = useMemo(() => {
@@ -436,12 +442,13 @@ export function ContactForm({ contact, addressBooks, allKeywords, onSave, onCanc
       phonesMap[`p${i}`] = obj;
     });
 
+    // Emit JSContact-standard kinds (RFC 9553) so the JMAP server stores them losslessly.
     const nameComponents = [];
-    if (prefix.trim()) nameComponents.push({ kind: "prefix" as const, value: prefix.trim() });
+    if (prefix.trim()) nameComponents.push({ kind: "title" as const, value: prefix.trim() });
     if (givenName.trim()) nameComponents.push({ kind: "given" as const, value: givenName.trim() });
-    if (additionalName.trim()) nameComponents.push({ kind: "additional" as const, value: additionalName.trim() });
+    if (additionalName.trim()) nameComponents.push({ kind: "given2" as const, value: additionalName.trim() });
     if (surname.trim()) nameComponents.push({ kind: "surname" as const, value: surname.trim() });
-    if (suffix.trim()) nameComponents.push({ kind: "suffix" as const, value: suffix.trim() });
+    if (suffix.trim()) nameComponents.push({ kind: "generation" as const, value: suffix.trim() });
 
     const titlesMap: Record<string, { name: string; kind?: "title" | "role" }> = {};
     if (jobTitle.trim()) titlesMap["t0"] = { name: jobTitle.trim(), kind: "title" };

components/contacts/contacts-sidebar.tsx

@@ -27,6 +27,9 @@ interface ContactsSidebarProps {
   onDropContacts?: (contactIds: string[], addressBook: AddressBook) => void;
   onDropContactsToCategory?: (contactIds: string[], keyword: string) => void;
   onRenameAddressBook?: (addressBook: AddressBook) => void;
+  onShareAddressBook?: (addressBook: AddressBook) => void;
+  onCreateContactInBook?: (addressBook: AddressBook) => void;
+  onDeleteAddressBook?: (addressBook: AddressBook) => void;
   onRenameKeyword?: (keyword: string) => void;
   className?: string;
 }
@@ -62,6 +65,9 @@ export function ContactsSidebar({
   onDropContacts,
   onDropContactsToCategory,
   onRenameAddressBook,
+  onShareAddressBook,
+  onCreateContactInBook,
+  onDeleteAddressBook,
   onRenameKeyword,
   className,
 }: ContactsSidebarProps) {
@@ -288,7 +294,7 @@ export function ContactsSidebar({
                 contactCount={contactCountByBook[book.id] || 0}
                 onSelect={() => onSelectCategory({ addressBookId: book.id })}
                 onDropContacts={onDropContacts}
-                onContextMenu={onRenameAddressBook ? (e) => openBookContextMenu(e, book) : undefined}
+                onContextMenu={(onRenameAddressBook || onShareAddressBook || onCreateContactInBook || onDeleteAddressBook) ? (e) => openBookContextMenu(e, book) : undefined}
               />
             ))}
           </div>
@@ -430,7 +436,7 @@ export function ContactsSidebar({
                 contactCount={contactCountByBook[book.id] || 0}
                 onSelect={() => onSelectCategory({ addressBookId: book.id })}
                 onDropContacts={onDropContacts}
-                onContextMenu={onRenameAddressBook ? (e) => openBookContextMenu(e, book) : undefined}
+                onContextMenu={(onRenameAddressBook || onShareAddressBook || onCreateContactInBook || onDeleteAddressBook) ? (e) => openBookContextMenu(e, book) : undefined}
               />
             ))}
           </div>
@@ -438,24 +444,65 @@ export function ContactsSidebar({
       </div>
 
       {/* Address book context menu */}
-      {bookContextMenu.data && onRenameAddressBook && (
-        <ContextMenu
-          ref={bookMenuRef}
-          isOpen={bookContextMenu.isOpen}
-          position={bookContextMenu.position}
-          onClose={closeBookContextMenu}
-        >
-          <ContextMenuItem
-            icon={Pencil}
-            label={t("address_books.rename")}
-            onClick={() => {
-              const book = bookContextMenu.data!;
-              closeBookContextMenu();
-              onRenameAddressBook(book);
-            }}
-          />
-        </ContextMenu>
-      )}
+      {bookContextMenu.data && (onRenameAddressBook || onShareAddressBook || onCreateContactInBook || onDeleteAddressBook) && (() => {
+        const book = bookContextMenu.data;
+        const canCreate = onCreateContactInBook && book.myRights?.mayWrite !== false;
+        const canRename = onRenameAddressBook && book.myRights?.mayWrite !== false;
+        const canShare = onShareAddressBook && book.myRights?.mayShare && !book.isShared;
+        const canDelete = onDeleteAddressBook && !book.isDefault && !book.isShared && book.myRights?.mayDelete !== false;
+        const showSeparator = (canCreate || canRename || canShare) && canDelete;
+        return (
+          <ContextMenu
+            ref={bookMenuRef}
+            isOpen={bookContextMenu.isOpen}
+            position={bookContextMenu.position}
+            onClose={closeBookContextMenu}
+          >
+            {canCreate && (
+              <ContextMenuItem
+                icon={UserPlus}
+                label={t("address_books.new_contact_in_book")}
+                onClick={() => {
+                  closeBookContextMenu();
+                  onCreateContactInBook(book);
+                }}
+              />
+            )}
+            {canRename && (
+              <ContextMenuItem
+                icon={Pencil}
+                label={t("address_books.rename")}
+                onClick={() => {
+                  closeBookContextMenu();
+                  onRenameAddressBook(book);
+                }}
+              />
+            )}
+            {canShare && (
+              <ContextMenuItem
+                icon={Users}
+                label={t("address_books.share")}
+                onClick={() => {
+                  closeBookContextMenu();
+                  onShareAddressBook(book);
+                }}
+              />
+            )}
+            {showSeparator && <ContextMenuSeparator />}
+            {canDelete && (
+              <ContextMenuItem
+                icon={Trash2}
+                label={t("address_books.delete")}
+                onClick={() => {
+                  closeBookContextMenu();
+                  onDeleteAddressBook(book);
+                }}
+                destructive
+              />
+            )}
+          </ContextMenu>
+        );
+      })()}
 
       {/* Keyword (category) context menu */}
       {keywordContextMenu.data && onRenameKeyword && (

components/email/email-composer.tsx

@@ -31,6 +31,7 @@ import { TemplateForm } from "@/components/templates/template-form";
 import type { EmailTemplate } from "@/lib/template-types";
 import { appendPlainTextSignature, getPlainTextSignature } from "@/lib/signature-utils";
 import { findReplyIdentityId } from "@/lib/reply-identity";
+import { computeReplyThreadingHeaders } from "@/lib/email-threading";
 import { RichTextEditor } from "@/components/email/rich-text-editor";
 
 /** Strip HTML tags and decode entities to get a plain-text version */
@@ -67,6 +68,8 @@ interface EmailComposerProps {
     fromName?: string;
     identityId?: string;
     attachments?: Array<{ blobId: string; name: string; type: string; size: number; disposition?: 'attachment' | 'inline'; cid?: string }>;
+    inReplyTo?: string[];
+    references?: string[];
   }) => void | Promise<void>;
   onClose?: () => void;
   onDiscardDraft?: (draftId: string) => void;
@@ -87,6 +90,11 @@ interface EmailComposerProps {
     receivedAt?: string;
     accountId?: string;
     attachments?: Array<{ blobId: string; name?: string; type: string; size: number; cid?: string; disposition?: string }>;
+    // Threading: parent's Message-ID and References, used to set RFC 5322
+    // In-Reply-To and References on outgoing replies. See #234.
+    messageId?: string;
+    inReplyTo?: string[];
+    references?: string[];
   };
 }
 
@@ -116,6 +124,7 @@ export function EmailComposer({
   const tCommon = useTranslations('common');
   const timeFormat = useSettingsStore((state) => state.timeFormat);
   const plainTextMode = useSettingsStore((state) => state.plainTextMode);
+  const subAddressDelimiter = useSettingsStore((state) => state.subAddressDelimiter);
   const autoSelectReplyIdentity = useSettingsStore((state) => state.autoSelectReplyIdentity);
   const attachmentReminderEnabled = useSettingsStore((state) => state.attachmentReminderEnabled);
   const attachmentReminderKeywords = useSettingsStore((state) => state.attachmentReminderKeywords);
@@ -721,7 +730,7 @@ export function EmailComposer({
     // Generate sub-addressed email if tag is set
     const fromEmail = currentIdentity?.email
       ? subAddressTag
-        ? generateSubAddress(currentIdentity.email, subAddressTag)
+        ? generateSubAddress(currentIdentity.email, subAddressTag, subAddressDelimiter)
         : currentIdentity.email
       : undefined;
 
@@ -736,7 +745,8 @@ export function EmailComposer({
         fromEmail,
         draftId || undefined,
         uploadedAttachments,
-        currentIdentity?.name || undefined
+        currentIdentity?.name || undefined,
+        plainTextMode ? undefined : body
       );
 
       setDraftId(savedDraftId);
@@ -812,19 +822,27 @@ export function EmailComposer({
     attachments: Array<{ blobId: string; name: string; type: string; size: number; disposition: 'inline'; cid: string }>;
   } => {
     const known = inlineImagesRef.current;
-    if (known.length === 0) return { html, attachments: [] };
-
     const doc = new DOMParser().parseFromString(`<body>${html}</body>`, 'text/html');
     const used = new Map<string, typeof known[number]>();
 
-    doc.querySelectorAll('img[data-cid]').forEach((img) => {
-      const cid = img.getAttribute('data-cid');
-      if (!cid) return;
-      const entry = known.find((e) => e.cid === cid);
-      if (!entry) return;
-      img.setAttribute('src', `cid:${cid}`);
-      img.removeAttribute('data-cid');
-      used.set(cid, entry);
+    if (known.length > 0) {
+      doc.querySelectorAll('img[data-cid]').forEach((img) => {
+        const cid = img.getAttribute('data-cid');
+        if (!cid) return;
+        const entry = known.find((e) => e.cid === cid);
+        if (!entry) return;
+        img.setAttribute('src', `cid:${cid}`);
+        img.removeAttribute('data-cid');
+        used.set(cid, entry);
+      });
+    }
+
+    // Recipient mail clients apply default <p> margins inside table cells,
+    // inflating row height. Tiptap wraps cell text in <p>, so force margin:0
+    // to match the composer's tight rows.
+    doc.querySelectorAll('td > p, th > p').forEach((p) => {
+      const existing = p.getAttribute('style') || '';
+      p.setAttribute('style', `margin:0;${existing}`);
     });
 
     return {
@@ -889,7 +907,7 @@ export function EmailComposer({
 
     const fromEmail = currentIdentity?.email
       ? subAddressTag
-        ? generateSubAddress(currentIdentity.email, subAddressTag)
+        ? generateSubAddress(currentIdentity.email, subAddressTag, subAddressDelimiter)
         : currentIdentity.email
       : undefined;
 
@@ -905,6 +923,11 @@ export function EmailComposer({
       return '';
     };
 
+    // RFC 5322 §3.6.4 threading — only continues the chain on a reply, not a forward.
+    const threadingHeaders = (mode === 'reply' || mode === 'replyAll')
+      ? computeReplyThreadingHeaders(replyTo)
+      : null;
+
     // In plain text mode, send text/plain only (no HTML body)
     const finalBody = plainTextMode
       ? appendPlainTextSignature(body, currentIdentity)
@@ -968,12 +991,22 @@ export function EmailComposer({
         }
 
         // 4. Build canonical MIME
+        // mime-builder takes inReplyTo as a single ref-form msg-id (with brackets);
+        // references stays an array. threadingHeaders contains bare msg-ids.
+        const mimeInReplyTo = threadingHeaders?.inReplyTo[0]
+          ? `<${threadingHeaders.inReplyTo[0]}>`
+          : undefined;
+        const mimeReferences = threadingHeaders?.references.length
+          ? threadingHeaders.references.map(id => `<${id}>`)
+          : undefined;
         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,
+          inReplyTo: mimeInReplyTo,
+          references: mimeReferences,
           textBody: finalBody,
           htmlBody: finalHtmlBody,
           attachments: mimeAttachments.length > 0 ? mimeAttachments : undefined,
@@ -986,6 +1019,8 @@ export function EmailComposer({
           to: toAddresses.map(e => ({ email: e })),
           cc: ccAddresses.length > 0 ? ccAddresses.map(e => ({ email: e })) : undefined,
           subject,
+          inReplyTo: mimeInReplyTo,
+          references: mimeReferences,
         };
 
         // 5. Sign if enabled
@@ -1042,6 +1077,8 @@ export function EmailComposer({
           fromName: currentIdentity?.name || undefined,
           identityId: currentIdentity?.id,
           attachments: uploadedAttachments.length > 0 ? uploadedAttachments : undefined,
+          inReplyTo: threadingHeaders?.inReplyTo,
+          references: threadingHeaders?.references,
         });
       }
 
@@ -1100,8 +1137,14 @@ export function EmailComposer({
   };
 
   return (
+    <div className={cn("flex h-full bg-background", className)}>
+      <PluginSlot
+        name="composer-sidebar"
+        className="hidden md:flex shrink-0 h-full overflow-hidden border-r border-border"
+      />
+      {/* Right-side composer sidebar slot is rendered after the main content div below. */}
     <div
-      className={cn("flex flex-col h-full bg-background relative", className)}
+      className="flex flex-col h-full bg-background relative flex-1 min-w-0"
       data-tour="composer"
       onDragEnter={handleDragEnter}
       onDragLeave={handleDragLeave}
@@ -1173,7 +1216,7 @@ export function EmailComposer({
                 >
                   {identities.map((identity) => {
                     const displayEmail = subAddressTag
-                      ? generateSubAddress(identity.email, subAddressTag)
+                      ? generateSubAddress(identity.email, subAddressTag, subAddressDelimiter)
                       : identity.email;
                     return (
                       <option key={identity.id} value={identity.id}>
@@ -1186,7 +1229,7 @@ export function EmailComposer({
                 <span className="text-sm text-foreground flex-1 truncate">
                   {subAddressTag ? (
                     <span className="font-mono">
-                      {generateSubAddress(primaryIdentity?.email || '', subAddressTag)}
+                      {generateSubAddress(primaryIdentity?.email || '', subAddressTag, subAddressDelimiter)}
                     </span>
                   ) : (
                     <>
@@ -1674,6 +1717,11 @@ export function EmailComposer({
         </div>
       )}
     </div>
+      <PluginSlot
+        name="composer-sidebar-right"
+        className="hidden md:flex shrink-0 h-full overflow-hidden border-l border-border"
+      />
+    </div>
   );
 }
 

components/email/email-identity-badge.tsx

@@ -5,6 +5,7 @@ import { Mail, Tag } from 'lucide-react';
 import { cn } from '@/lib/utils';
 import type { Email, Identity } from '@/lib/jmap/types';
 import { parseSubAddress } from '@/lib/sub-addressing';
+import { useSettingsStore } from '@/stores/settings-store';
 
 interface EmailIdentityBadgeProps {
   email: Email;
@@ -20,12 +21,13 @@ export function EmailIdentityBadge({
   className,
 }: EmailIdentityBadgeProps) {
   const t = useTranslations('identities.badge');
+  const subAddressDelimiter = useSettingsStore((state) => state.subAddressDelimiter);
 
   const fromAddress = email.from?.[0]?.email;
   if (!fromAddress) return null;
 
   // Parse the from address to check for sub-addressing
-  const parsedFrom = parseSubAddress(fromAddress);
+  const parsedFrom = parseSubAddress(fromAddress, subAddressDelimiter);
 
   // Find matching identity (email sent BY the user)
   const matchingIdentity = identities.find(
@@ -37,7 +39,7 @@ export function EmailIdentityBadge({
   if (!matchingIdentity) {
     // Check all TO addresses for sub-address tags matching user's identities
     for (const recipient of email.to || []) {
-      const parsedTo = parseSubAddress(recipient.email);
+      const parsedTo = parseSubAddress(recipient.email, subAddressDelimiter);
       if (parsedTo.tag) {
         // Check if this base email matches any of the user's identities
         const matchingToIdentity = identities.find(
@@ -70,7 +72,7 @@ export function EmailIdentityBadge({
           title={t('sub_address_tag', { tag: displayTag })}
         >
           <Tag className="w-3 h-3" />
-          <span className="font-mono">+{displayTag}</span>
+          <span className="font-mono">{subAddressDelimiter}{displayTag}</span>
         </div>
       );
     }
@@ -114,7 +116,7 @@ export function EmailIdentityBadge({
           aria-label={t('sub_address_tag', { tag: displayTag })}
         >
           <Tag className="w-3 h-3" />
-          <span className="font-mono">{t('subaddress_tag', { tag: displayTag })}</span>
+          <span className="font-mono">{subAddressDelimiter}{displayTag}</span>
         </div>
       )}
 

components/email/email-list-item.tsx

@@ -288,7 +288,7 @@ export function EmailListItem({ email, selected, onClick, onContextMenu, onToggl
               </div>
 
               {/* Third Line: Preview (controlled by showPreview setting) */}
-              {showPreview && density !== 'extra-compact' && (
+              {showPreview && density !== 'extra-compact' && density !== 'compact' && (
                 <p className={cn(
                   "text-sm leading-relaxed line-clamp-2",
                   isUnread

components/email/email-viewer.tsx

@@ -2285,7 +2285,7 @@ export function EmailViewer({
 
   // Sanitize and prepare email HTML content
   const emailContent = useMemo(() => {
-    if (!email) return { html: "", isHtml: false };
+    if (!email) return { html: "", isHtml: false, hasStyleTag: false };
 
     // Check if we have body values
     if (email.bodyValues) {
@@ -2338,8 +2338,7 @@ export function EmailViewer({
         );
 
         if (shouldBlockExternal) {
-          sanitizeConfig.FORBID_TAGS.push('link');
-          sanitizeConfig.FORBID_ATTR.push('background');
+          sanitizeConfig.FORBID_TAGS = [...sanitizeConfig.FORBID_TAGS, 'link'];
         }
 
         DOMPurify.addHook('afterSanitizeAttributes', (node) => {
@@ -2357,11 +2356,19 @@ export function EmailViewer({
               }
             }
 
+            const bgAttr = node.getAttribute?.('background');
+            if (bgAttr && (bgAttr.startsWith('http://') || bgAttr.startsWith('https://') || bgAttr.startsWith('//'))) {
+              node.setAttribute('data-blocked-background', bgAttr);
+              node.removeAttribute('background');
+              blockedExternalContent = true;
+            }
+
             if (htmlNode.style) {
               const style = htmlNode.style.cssText;
               if (style && style.includes('url(')) {
                 const urlMatch = style.match(/url\(['"]?(https?:\/\/[^'")\s]+)['"]?\)/gi);
                 if (urlMatch) {
+                  node.setAttribute('data-blocked-style', style);
                   htmlNode.style.cssText = style.replace(/url\(['"]?https?:\/\/[^'")\s]+['"]?\)/gi, 'url()');
                   blockedExternalContent = true;
                 }
@@ -2395,7 +2402,8 @@ export function EmailViewer({
 
         return {
           html: cleanHtml,
-          isHtml: true
+          isHtml: true,
+          hasStyleTag: /<style[\s>]/i.test(htmlContent),
         };
       }
 
@@ -2405,7 +2413,8 @@ export function EmailViewer({
 
         return {
           html: plainTextToSafeHtml(textContent),
-          isHtml: false
+          isHtml: false,
+          hasStyleTag: false,
         };
       }
     }
@@ -2419,15 +2428,21 @@ export function EmailViewer({
 
       return {
         html: `<div style="color: var(--color-muted-foreground); font-style: italic;">${previewHtml}</div>`,
-        isHtml: false
+        isHtml: false,
+        hasStyleTag: false,
       };
     }
 
     return {
       html: '<p style="color: var(--color-muted-foreground);">No content available</p>',
-      isHtml: false
+      isHtml: false,
+      hasStyleTag: false,
     };
-  }, [email, allowExternalContent, hasBlockedContent, externalContentPolicy, isSenderTrusted, isTrustedAddressBookSender, trustedSendersAddressBook, cidBlobUrls]);
+    // Intentionally omit allowExternalContent and trust state from deps:
+    // toggling permission imperatively unblocks content via restoreBlockedContent
+    // in an effect below, so the iframe srcDoc stays stable and doesn't reload/flash.
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [email, externalContentPolicy, cidBlobUrls]);
 
   // Override email content with S/MIME decrypted content when available
   const effectiveEmailContent = useMemo(() => {
@@ -2439,26 +2454,26 @@ export function EmailViewer({
         }
       );
       const cleanHtml = DOMPurify.sanitize(htmlWithCidUrls, EMAIL_IFRAME_SANITIZE_CONFIG);
-      return { html: cleanHtml, isHtml: true };
+      return { html: cleanHtml, isHtml: true, hasStyleTag: /<style[\s>]/i.test(smimeDecryptedHtml) };
     }
     if (smimeDecryptedText) {
-      return { html: plainTextToSafeHtml(smimeDecryptedText), isHtml: false };
+      return { html: plainTextToSafeHtml(smimeDecryptedText), isHtml: false, hasStyleTag: false };
     }
     // TNEF (winmail.dat) extracted content
     if (tnefHtml) {
       const cleanHtml = DOMPurify.sanitize(tnefHtml, EMAIL_IFRAME_SANITIZE_CONFIG);
-      return { html: cleanHtml, isHtml: true };
+      return { html: cleanHtml, isHtml: true, hasStyleTag: /<style[\s>]/i.test(tnefHtml) };
     }
     if (tnefText) {
-      return { html: plainTextToSafeHtml(tnefText), isHtml: false };
+      return { html: plainTextToSafeHtml(tnefText), isHtml: false, hasStyleTag: false };
     }
     // Embedded message/rfc822 unwrapped content
     if (embeddedEmailHtml) {
       const cleanHtml = DOMPurify.sanitize(embeddedEmailHtml, EMAIL_IFRAME_SANITIZE_CONFIG);
-      return { html: cleanHtml, isHtml: true };
+      return { html: cleanHtml, isHtml: true, hasStyleTag: /<style[\s>]/i.test(embeddedEmailHtml) };
     }
     if (embeddedEmailText) {
-      return { html: plainTextToSafeHtml(embeddedEmailText), isHtml: false };
+      return { html: plainTextToSafeHtml(embeddedEmailText), isHtml: false, hasStyleTag: false };
     }
     return emailContent;
   }, [cidBlobUrls, emailContent, smimeDecryptedHtml, smimeDecryptedText, tnefHtml, tnefText, embeddedEmailHtml, embeddedEmailText]);
@@ -2600,10 +2615,14 @@ export function EmailViewer({
 
     const colorScheme = isDark && emailHasNativeDarkMode ? 'light dark' : 'light';
 
+    // Bare HTML emails (no <style>) tend to be plain prose without their own
+    // layout — give them the same padding as plain-text mails (.email-content-text).
+    const bodyPadding = effectiveEmailContent.hasStyleTag ? '0' : '1rem 1.25rem';
+
     return `<!DOCTYPE html>
 <html style="color-scheme: ${colorScheme};"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1">
 <style>
-  body { margin: 0; padding: 0; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; font-size: 14px; line-height: 1.6; color: #1a1a1a; background: #ffffff; word-wrap: break-word; overflow-wrap: break-word; }
+  body { margin: 0; padding: ${bodyPadding}; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; font-size: 14px; line-height: 1.6; color: #1a1a1a; background: #ffffff; word-wrap: break-word; overflow-wrap: break-word; }
   img { max-width: 100% !important; height: auto !important; }
   a { color: #1a73e8; }
   table { max-width: 100% !important; table-layout: auto; overflow-wrap: break-word; }
@@ -2613,6 +2632,79 @@ export function EmailViewer({
 </style></head><body>${effectiveEmailContent.html}</body></html>`;
   }, [effectiveEmailContent.html, effectiveEmailContent.isHtml, isDark, emailHasNativeDarkMode]);
 
+  // Imperatively restore blocked external content inside the iframe document.
+  // Avoids re-rendering the iframe srcDoc (which would reload and flash) when
+  // the user clicks "Load images" or "Trust sender".
+  const restoreBlockedContent = useCallback(() => {
+    const doc = iframeRef.current?.contentDocument;
+    if (!doc) return;
+
+    doc.querySelectorAll('img[data-blocked-src]').forEach((node) => {
+      const el = node as HTMLImageElement;
+      const src = el.getAttribute('data-blocked-src');
+      if (src) {
+        el.setAttribute('src', src);
+        el.style.display = '';
+        el.removeAttribute('data-blocked-src');
+      }
+    });
+
+    doc.querySelectorAll('[data-blocked-style]').forEach((node) => {
+      const el = node as HTMLElement;
+      const style = el.getAttribute('data-blocked-style');
+      if (style !== null) {
+        el.style.cssText = style;
+        el.removeAttribute('data-blocked-style');
+      }
+    });
+
+    doc.querySelectorAll('[data-blocked-background]').forEach((node) => {
+      const el = node as HTMLElement;
+      const bg = el.getAttribute('data-blocked-background');
+      if (bg) {
+        el.setAttribute('background', bg);
+        el.removeAttribute('data-blocked-background');
+      }
+    });
+
+    doc.querySelectorAll('[data-blocked-collapsed-style]').forEach((node) => {
+      const el = node as HTMLElement;
+      const style = el.getAttribute('data-blocked-collapsed-style');
+      if (style !== null) {
+        el.style.cssText = style;
+        el.removeAttribute('data-blocked-collapsed-style');
+      }
+    });
+  }, []);
+
+  // Whenever permission is granted (allow toggled, or sender becomes trusted),
+  // restore blocked content in the existing iframe — no srcDoc rebuild.
+  const senderEmailLower = email?.from?.[0]?.email?.toLowerCase();
+  const senderIsTrustedNow = senderEmailLower
+    ? isSenderTrusted(senderEmailLower) || (trustedSendersAddressBook && isTrustedAddressBookSender(senderEmailLower))
+    : false;
+  useEffect(() => {
+    if (!hasBlockedContent) return;
+    if (!allowExternalContent && !senderIsTrustedNow) return;
+    restoreBlockedContent();
+  }, [allowExternalContent, senderIsTrustedNow, hasBlockedContent, restoreBlockedContent]);
+
+  // Tracks the last rendered body height so the loading skeleton can hold
+  // the same size — avoids the body shrink/expand flash when switching emails.
+  const lastBodyHeightRef = useRef<number>(300);
+
+  // True while the new email's body is still being fetched. Catches the
+  // window between selectedEmail changing and isLoading flipping true, so the
+  // quick reply / body don't flicker through a partial render.
+  const isBodyLoading = isLoading || !email?.bodyValues || Object.keys(email.bodyValues).length === 0;
+
+  // Gates the quick reply on the iframe having loaded the current srcDoc, so
+  // it doesn't flash in below a still-resizing iframe.
+  const [iframeReady, setIframeReady] = useState(false);
+  useLayoutEffect(() => {
+    setIframeReady(false);
+  }, [emailIframeSrcDoc]);
+
   const handleIframeLoad = useCallback(() => {
     const iframe = iframeRef.current;
     if (!iframe) return;
@@ -2623,9 +2715,13 @@ export function EmailViewer({
         const resizeObserver = new ResizeObserver(() => {
           const height = doc.documentElement.scrollHeight;
           iframe.style.height = height + 'px';
+          lastBodyHeightRef.current = height;
         });
         resizeObserver.observe(doc.body);
-        iframe.style.height = doc.documentElement.scrollHeight + 'px';
+        const initialHeight = doc.documentElement.scrollHeight;
+        iframe.style.height = initialHeight + 'px';
+        lastBodyHeightRef.current = initialHeight;
+        setIframeReady(true);
 
         // Make links open in new tab
         doc.querySelectorAll('a').forEach(a => {
@@ -2946,11 +3042,6 @@ export function EmailViewer({
 
       {/* Right: Organize actions - order: archive, delete, move, star, tag, spam, read state, print, view source */}
       <div className="flex items-center gap-0 sm:gap-0.5">
-        {isLoading && (
-          <div className="mr-2 flex items-center gap-1.5 text-muted-foreground">
-            <Loader2 className="w-4 h-4 animate-spin" />
-          </div>
-        )}
         {/* Archive */}
         <Button
           variant="ghost"
@@ -3629,15 +3720,6 @@ export function EmailViewer({
     )}
     {/* Main email content */}
     <div className="flex-1 flex flex-col h-full overflow-hidden min-w-0">
-      {/* Loading overlay when fetching new email */}
-      {isLoading && (
-        <div className="absolute inset-0 bg-background/60 backdrop-blur-[2px] z-50 flex items-center justify-center animate-in fade-in duration-200">
-          <div className="bg-background rounded-lg shadow-lg border border-border p-4 flex items-center gap-3">
-            <Loader2 className="w-5 h-5 animate-spin text-primary" />
-            <span className="text-sm font-medium text-foreground">{t('loading_email')}</span>
-          </div>
-        </div>
-      )}
       {/* === TOOLBAR (top position) === */}
       {toolbarPosition === 'top' && (
         <div className={cn(
@@ -4634,14 +4716,28 @@ export function EmailViewer({
           <PluginSlot name="email-banner" extraProps={{ email }} />
 
           {/* Email Body */}
-          <div className="email-content-wrapper overflow-x-auto">
-            {effectiveEmailContent.isHtml ? (
+          <div className={cn(
+            "email-content-wrapper overflow-x-auto",
+            emailAlwaysLightMode ? "bg-white email-content-light" : "bg-background"
+          )}>
+            {isBodyLoading ? (
+              <div
+                className="space-y-3 px-6 py-4 animate-pulse"
+                style={{ minHeight: `${lastBodyHeightRef.current}px` }}
+              >
+                <div className="h-2 bg-muted/15 rounded w-full"></div>
+                <div className="h-2 bg-muted/15 rounded w-5/6"></div>
+                <div className="h-2 bg-muted/15 rounded w-4/6"></div>
+                <div className="h-2 bg-muted/15 rounded w-full"></div>
+                <div className="h-2 bg-muted/15 rounded w-3/4"></div>
+              </div>
+            ) : effectiveEmailContent.isHtml ? (
               <iframe
                 ref={iframeRef}
                 srcDoc={emailIframeSrcDoc}
                 sandbox="allow-same-origin allow-popups allow-popups-to-escape-sandbox"
                 title="Email content"
-                className="w-full border-0 rounded"
+                className="w-full border-0"
                 style={{ minHeight: '100px', colorScheme: isDark && emailHasNativeDarkMode ? 'light dark' : 'light' }}
                 onLoad={handleIframeLoad}
               />
@@ -4662,8 +4758,8 @@ export function EmailViewer({
 
           <PluginSlot name="email-footer" />
 
-          {/* Quick Reply Section - hidden for drafts */}
-          {!isDraft && (<div className={cn(
+          {/* Quick Reply Section - hidden for drafts and while loading a new email */}
+          {!isDraft && !isBodyLoading && (effectiveEmailContent.isHtml ? iframeReady : true) && (<div className={cn(
             "mt-6 mx-6 mb-6 bg-background rounded-lg shadow-sm border transition-all",
             isQuickReplyFocused || quickReplyText ? "border-primary" : "border-border"
           )}>

components/email/rich-text-editor.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import React, { useEffect, useCallback } from "react";
+import React, { useEffect, useCallback, useState, useRef } from "react";
 import { useEditor, EditorContent } from "@tiptap/react";
 import StarterKit from "@tiptap/starter-kit";
 import Underline from "@tiptap/extension-underline";
@@ -10,6 +10,10 @@ import { TextStyle } from "@tiptap/extension-text-style";
 import Color from "@tiptap/extension-color";
 import { ResizableImage } from "@/components/email/resizable-image";
 import Placeholder from "@tiptap/extension-placeholder";
+import { Table } from "@tiptap/extension-table";
+import { TableRow } from "@tiptap/extension-table-row";
+import { TableHeader } from "@tiptap/extension-table-header";
+import { TableCell } from "@tiptap/extension-table-cell";
 import { cn } from "@/lib/utils";
 import {
   Bold,
@@ -29,6 +33,10 @@ import {
   RemoveFormatting,
   Heading1,
   Heading2,
+  Table as TableIcon,
+  Trash2,
+  Rows3,
+  Columns3,
 } from "lucide-react";
 
 export interface InlineImageUpload {
@@ -79,6 +87,43 @@ function ToolbarSeparator() {
   return <div className="w-px h-5 bg-border mx-0.5" />;
 }
 
+const TABLE_PICKER_ROWS = 6;
+const TABLE_PICKER_COLS = 8;
+
+function TableSizePicker({ onPick }: { onPick: (rows: number, cols: number) => void }) {
+  const [hover, setHover] = useState<{ r: number; c: number } | null>(null);
+  return (
+    <div>
+      <div
+        className="grid gap-0.5"
+        style={{ gridTemplateColumns: `repeat(${TABLE_PICKER_COLS}, 1fr)` }}
+        onMouseLeave={() => setHover(null)}
+      >
+        {Array.from({ length: TABLE_PICKER_ROWS * TABLE_PICKER_COLS }).map((_, i) => {
+          const r = Math.floor(i / TABLE_PICKER_COLS);
+          const c = i % TABLE_PICKER_COLS;
+          const active = hover && r <= hover.r && c <= hover.c;
+          return (
+            <button
+              key={i}
+              type="button"
+              onMouseEnter={() => setHover({ r, c })}
+              onClick={() => onPick(r + 1, c + 1)}
+              className={cn(
+                "w-4 h-4 border border-border/60 rounded-[2px] transition-colors",
+                active ? "bg-primary border-primary" : "bg-background hover:bg-accent"
+              )}
+            />
+          );
+        })}
+      </div>
+      <div className="text-xs text-muted-foreground mt-1.5 text-center">
+        {hover ? `${hover.r + 1} × ${hover.c + 1}` : "Pick size"}
+      </div>
+    </div>
+  );
+}
+
 export function RichTextEditor({
   content,
   onChange,
@@ -109,6 +154,27 @@ export function RichTextEditor({
       Placeholder.configure({
         placeholder,
       }),
+      Table.configure({
+        resizable: true,
+        HTMLAttributes: {
+          border: "1",
+          cellpadding: "6",
+          cellspacing: "0",
+          width: "100%",
+          style: "width:100%;border-collapse:collapse;",
+        },
+      }),
+      TableRow,
+      TableHeader.configure({
+        HTMLAttributes: {
+          style: "padding:6px 8px;border:1px solid #ccc;background-color:#f5f5f5;color:#1f2937;text-align:left;",
+        },
+      }),
+      TableCell.configure({
+        HTMLAttributes: {
+          style: "padding:6px 8px;border:1px solid #ccc;vertical-align:top;",
+        },
+      }),
     ],
     content,
     editorProps: {
@@ -188,6 +254,20 @@ export function RichTextEditor({
       .run();
   }, [editor]);
 
+  const [tableMenuOpen, setTableMenuOpen] = useState(false);
+  const tableWrapperRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    if (!tableMenuOpen) return;
+    const handler = (e: MouseEvent) => {
+      if (tableWrapperRef.current && !tableWrapperRef.current.contains(e.target as Node)) {
+        setTableMenuOpen(false);
+      }
+    };
+    document.addEventListener("mousedown", handler);
+    return () => document.removeEventListener("mousedown", handler);
+  }, [tableMenuOpen]);
+
   if (!editor) {
     return (
       <div className={cn("min-h-[100px]", className)} />
@@ -309,6 +389,89 @@ export function RichTextEditor({
           <LinkIcon className="w-4 h-4" />
         </ToolbarButton>
 
+        <div ref={tableWrapperRef} className="relative">
+          <ToolbarButton
+            active={editor.isActive("table")}
+            onClick={() => setTableMenuOpen((v) => !v)}
+            title="Table"
+          >
+            <TableIcon className="w-4 h-4" />
+          </ToolbarButton>
+          {tableMenuOpen && (
+            <div className="absolute z-50 top-full left-0 mt-1 bg-popover border border-border rounded-md shadow-md p-2 min-w-[200px]">
+              {editor.isActive("table") ? (
+                <div className="flex flex-col gap-0.5">
+                  <button
+                    type="button"
+                    className="flex items-center gap-2 px-2 py-1.5 text-sm rounded hover:bg-accent text-left"
+                    onClick={() => { editor.chain().focus().addRowBefore().run(); setTableMenuOpen(false); }}
+                  >
+                    <Rows3 className="w-4 h-4" /> Add row above
+                  </button>
+                  <button
+                    type="button"
+                    className="flex items-center gap-2 px-2 py-1.5 text-sm rounded hover:bg-accent text-left"
+                    onClick={() => { editor.chain().focus().addRowAfter().run(); setTableMenuOpen(false); }}
+                  >
+                    <Rows3 className="w-4 h-4" /> Add row below
+                  </button>
+                  <button
+                    type="button"
+                    className="flex items-center gap-2 px-2 py-1.5 text-sm rounded hover:bg-accent text-left"
+                    onClick={() => { editor.chain().focus().addColumnBefore().run(); setTableMenuOpen(false); }}
+                  >
+                    <Columns3 className="w-4 h-4" /> Add column before
+                  </button>
+                  <button
+                    type="button"
+                    className="flex items-center gap-2 px-2 py-1.5 text-sm rounded hover:bg-accent text-left"
+                    onClick={() => { editor.chain().focus().addColumnAfter().run(); setTableMenuOpen(false); }}
+                  >
+                    <Columns3 className="w-4 h-4" /> Add column after
+                  </button>
+                  <div className="h-px bg-border my-1" />
+                  <button
+                    type="button"
+                    className="flex items-center gap-2 px-2 py-1.5 text-sm rounded hover:bg-accent text-left"
+                    onClick={() => { editor.chain().focus().deleteRow().run(); setTableMenuOpen(false); }}
+                  >
+                    <Trash2 className="w-4 h-4" /> Delete row
+                  </button>
+                  <button
+                    type="button"
+                    className="flex items-center gap-2 px-2 py-1.5 text-sm rounded hover:bg-accent text-left"
+                    onClick={() => { editor.chain().focus().deleteColumn().run(); setTableMenuOpen(false); }}
+                  >
+                    <Trash2 className="w-4 h-4" /> Delete column
+                  </button>
+                  <button
+                    type="button"
+                    className="flex items-center gap-2 px-2 py-1.5 text-sm rounded hover:bg-accent text-left"
+                    onClick={() => { editor.chain().focus().toggleHeaderRow().run(); setTableMenuOpen(false); }}
+                  >
+                    <Rows3 className="w-4 h-4" /> Toggle header row
+                  </button>
+                  <div className="h-px bg-border my-1" />
+                  <button
+                    type="button"
+                    className="flex items-center gap-2 px-2 py-1.5 text-sm rounded hover:bg-accent text-left text-red-600 dark:text-red-400"
+                    onClick={() => { editor.chain().focus().deleteTable().run(); setTableMenuOpen(false); }}
+                  >
+                    <Trash2 className="w-4 h-4" /> Delete table
+                  </button>
+                </div>
+              ) : (
+                <TableSizePicker
+                  onPick={(rows, cols) => {
+                    editor.chain().focus().insertTable({ rows, cols, withHeaderRow: true }).run();
+                    setTableMenuOpen(false);
+                  }}
+                />
+              )}
+            </div>
+          )}
+        </div>
+
         <ToolbarSeparator />
 
         <ToolbarButton

components/email/thread-list-item.tsx

@@ -309,7 +309,7 @@ const SingleEmailItem = React.forwardRef<HTMLDivElement, SingleEmailItemProps>(
                   {email.subject || "(no subject)"}
                 </div>
 
-                {showPreview && density !== 'extra-compact' && (
+                {showPreview && density !== 'extra-compact' && density !== 'compact' && (
                   <p className={cn(
                     "text-sm leading-relaxed line-clamp-2",
                     isUnread
@@ -715,7 +715,7 @@ export const ThreadListItem = React.forwardRef<HTMLDivElement, ThreadListItemPro
                     {latestEmail.subject || "(no subject)"}
                   </div>
 
-                  {showPreview && density !== 'extra-compact' && (
+                  {showPreview && density !== 'extra-compact' && density !== 'compact' && (
                     <p className={cn(
                       "text-sm leading-relaxed line-clamp-2",
                       hasUnread

components/identity/sub-address-helper.tsx

@@ -7,6 +7,7 @@ import { cn } from '@/lib/utils';
 import { Button } from '@/components/ui/button';
 import { Input } from '@/components/ui/input';
 import { useIdentityStore } from '@/stores/identity-store';
+import { useSettingsStore } from '@/stores/settings-store';
 import {
   generateSubAddress,
   extractDomain,
@@ -35,6 +36,7 @@ export function SubAddressHelper({
   const popoverRef = useRef<HTMLDivElement>(null);
 
   const { subAddress, addRecentTag, addTagSuggestion } = useIdentityStore();
+  const subAddressDelimiter = useSettingsStore((state) => state.subAddressDelimiter);
 
   // Get suggestions based on recipient (memoized for performance)
   const suggestions = useMemo(() => {
@@ -47,7 +49,7 @@ export function SubAddressHelper({
   }, [recipientEmails]);
 
   // Generate preview
-  const preview = tag ? generateSubAddress(baseEmail, tag) : baseEmail;
+  const preview = tag ? generateSubAddress(baseEmail, tag, subAddressDelimiter) : baseEmail;
 
   // Close popover when clicking outside
   useEffect(() => {
@@ -226,7 +228,7 @@ export function SubAddressHelper({
 
           {/* Help Text */}
           <div className="mb-3 text-xs text-muted-foreground">
-            {t('help_text')}
+            {t('help_text', { delimiter: subAddressDelimiter })}
           </div>
 
           {/* Use Address Button */}

components/layout/navigation-rail.tsx

@@ -335,7 +335,7 @@ export function NavigationRail({
           );
         })}
 
-        {/* Admin (Stalwart admins) — hard nav because /admin lives outside the [locale] tree */}
+        {/* Admin (Stalwart admins) - hard nav because /admin lives outside the [locale] tree */}
         {isStalwartAdmin && (
           <a
             href="/admin"

components/providers/intl-provider.tsx

@@ -3,6 +3,7 @@
 import { useEffect, useState } from 'react';
 import { NextIntlClientProvider } from 'next-intl';
 import { useLocaleStore } from '@/stores/locale-store';
+import csMessages from '@/locales/cs/common.json';
 import enMessages from '@/locales/en/common.json';
 import frMessages from '@/locales/fr/common.json';
 import jaMessages from '@/locales/ja/common.json';
@@ -15,11 +16,13 @@ import nlMessages from '@/locales/nl/common.json';
 import plMessages from '@/locales/pl/common.json';
 import ptMessages from '@/locales/pt/common.json';
 import ruMessages from '@/locales/ru/common.json';
+import trMessages from '@/locales/tr/common.json';
 import ukMessages from '@/locales/uk/common.json';
 import zhMessages from '@/locales/zh/common.json';
 
 // Pre-loaded translations (loaded at build time, not runtime)
 const ALL_MESSAGES = {
+  cs: csMessages,
   en: enMessages,
   fr: frMessages,
   ja: jaMessages,
@@ -32,6 +35,7 @@ const ALL_MESSAGES = {
   pl: plMessages,
   pt: ptMessages,
   ru: ruMessages,
+  tr: trMessages,
   uk: ukMessages,
   zh: zhMessages,
 };

components/settings/address-book-management-settings.tsx

@@ -2,13 +2,14 @@
 
 import { useEffect, useState } from "react";
 import { useTranslations } from "next-intl";
-import { Book, Pencil, Share2, Tag } from "lucide-react";
+import { Book, Pencil, Share2, Tag, Users } from "lucide-react";
 import { useContactStore } from "@/stores/contact-store";
 import { useAuthStore } from "@/stores/auth-store";
 import { toast } from "@/stores/toast-store";
 import { SettingsSection } from "./settings-section";
 import { cn } from "@/lib/utils";
-import type { AddressBook } from "@/lib/jmap/types";
+import type { AddressBook, AddressBookRights } from "@/lib/jmap/types";
+import { ShareCollectionDialog } from "./share-collection-dialog";
 
 function AddressBookEditRow({
   initial,
@@ -70,9 +71,10 @@ export function AddressBookManagementSettings() {
   const tContacts = useTranslations("contacts");
   const tSettings = useTranslations("settings.contacts");
   const { client } = useAuthStore();
-  const { addressBooks, contacts, supportsSync, fetchAddressBooks, renameAddressBook, renameKeyword } = useContactStore();
+  const { addressBooks, contacts, supportsSync, fetchAddressBooks, renameAddressBook, shareAddressBook, renameKeyword } = useContactStore();
   const [editingId, setEditingId] = useState<string | null>(null);
   const [editingKeyword, setEditingKeyword] = useState<string | null>(null);
+  const [sharingId, setSharingId] = useState<string | null>(null);
   const [isLoading, setIsLoading] = useState(false);
 
   useEffect(() => {
@@ -148,6 +150,16 @@ export function AddressBookManagementSettings() {
               <Pencil className="w-3.5 h-3.5" />
             </button>
           )}
+          {!book.isShared && book.myRights?.mayShare && (
+            <button
+              type="button"
+              onClick={() => setSharingId(book.id)}
+              className="p-1.5 rounded-md hover:bg-muted text-muted-foreground hover:text-foreground transition-colors"
+              title={t("share")}
+            >
+              <Users className="w-3.5 h-3.5" />
+            </button>
+          )}
         </div>
       </div>
     );
@@ -242,6 +254,24 @@ export function AddressBookManagementSettings() {
         </div>
       </SettingsSection>
     </div>
+
+    {sharingId && client && (() => {
+      const book = addressBooks.find((b) => b.id === sharingId);
+      if (!book) return null;
+      return (
+        <ShareCollectionDialog
+          client={client}
+          kind="addressBook"
+          collectionName={book.name}
+          shareWith={book.shareWith}
+          ownAccountId={client.getAccountId()}
+          onShare={async (principalId, rights) => {
+            await shareAddressBook(client, book, principalId, rights as AddressBookRights | null);
+          }}
+          onClose={() => setSharingId(null)}
+        />
+      );
+    })()}
     </>
   );
 }

components/settings/calendar-management-settings.tsx

@@ -7,7 +7,9 @@ import { useAuthStore } from '@/stores/auth-store';
 import { getActiveAccountSlotHeaders } from '@/lib/auth/active-account-slot';
 import { toast } from '@/stores/toast-store';
 import { SettingsSection } from './settings-section';
-import { Plus, Pencil, Trash2, Calendar as CalendarIcon, Copy, Link, Upload, Globe, RefreshCw, Eraser } from 'lucide-react';
+import { Plus, Pencil, Trash2, Calendar as CalendarIcon, Copy, Link, Upload, Globe, RefreshCw, Eraser, Users } from 'lucide-react';
+import { ShareCollectionDialog } from './share-collection-dialog';
+import type { CalendarRights } from '@/lib/jmap/types';
 import { cn, formatDateTime } from '@/lib/utils';
 import { ICalImportModal } from '@/components/calendar/ical-import-modal';
 import { ICalSubscriptionModal } from '@/components/calendar/ical-subscription-modal';
@@ -83,7 +85,7 @@ function CalendarColorPicker({
   );
 }
 
-function CalendarEditForm({
+export function CalendarEditForm({
   initial,
   onSave,
   onCancel,
@@ -153,7 +155,7 @@ export { CalendarColorPicker, CALENDAR_COLORS };
 export function CalendarManagementSettings() {
   const t = useTranslations('calendar.management');
   const { client, serverUrl, username } = useAuthStore();
-  const { calendars, updateCalendar, createCalendar, removeCalendar, clearCalendarEvents, fetchCalendars, icalSubscriptions, removeICalSubscription, refreshICalSubscription, isSubscriptionCalendar } = useCalendarStore();
+  const { calendars, updateCalendar, shareCalendar, createCalendar, removeCalendar, clearCalendarEvents, fetchCalendars, icalSubscriptions, removeICalSubscription, refreshICalSubscription, isSubscriptionCalendar } = useCalendarStore();
 
   const [discoveredCalDavUrls, setDiscoveredCalDavUrls] = useState<Record<string, string | null>>({});
   const [wellKnownCalDavUrl, setWellKnownCalDavUrl] = useState<string | null>(null);
@@ -164,6 +166,7 @@ export function CalendarManagementSettings() {
   const [clearingId, setClearingId] = useState<string | null>(null);
   const [isLoading, setIsLoading] = useState(false);
   const [colorPickerId, setColorPickerId] = useState<string | null>(null);
+  const [sharingId, setSharingId] = useState<string | null>(null);
   const [showImportModal, setShowImportModal] = useState(false);
   const [showSubscriptionModal, setShowSubscriptionModal] = useState(false);
   const [editingSubscription, setEditingSubscription] = useState<typeof icalSubscriptions[0] | null>(null);
@@ -522,6 +525,16 @@ export function CalendarManagementSettings() {
                 >
                   <Pencil className="w-3.5 h-3.5" />
                 </button>
+                {cal.myRights?.mayShare && !cal.isShared && !isSubscriptionCalendar(cal.id) && (
+                  <button
+                    type="button"
+                    onClick={() => setSharingId(cal.id)}
+                    className="p-1.5 rounded-md hover:bg-muted text-muted-foreground hover:text-foreground transition-colors"
+                    title={t('share')}
+                  >
+                    <Users className="w-3.5 h-3.5" />
+                  </button>
+                )}
                 <button
                   type="button"
                   onClick={() => setClearingId(cal.id)}
@@ -689,6 +702,24 @@ export function CalendarManagementSettings() {
           onClose={() => setEditingSubscription(null)}
         />
       )}
+
+      {sharingId && client && (() => {
+        const cal = calendars.find((c) => c.id === sharingId);
+        if (!cal) return null;
+        return (
+          <ShareCollectionDialog
+            client={client}
+            kind="calendar"
+            collectionName={cal.name}
+            shareWith={cal.shareWith}
+            ownAccountId={client.getAccountId()}
+            onShare={async (principalId, rights) => {
+              await shareCalendar(client, cal.id, principalId, rights as CalendarRights | null);
+            }}
+            onClose={() => setSharingId(null)}
+          />
+        );
+      })()}
     </SettingsSection>
   );
 }

components/settings/composing-settings.tsx

@@ -4,8 +4,16 @@ import { useState, useCallback } from 'react';
 import { useTranslations } from 'next-intl';
 import { useConfig } from '@/hooks/use-config';
 import { useSettingsStore } from '@/stores/settings-store';
-import { SettingsSection, SettingItem, ToggleSwitch } from './settings-section';
+import { SettingsSection, SettingItem, Select, ToggleSwitch } from './settings-section';
 import { Mail, X } from 'lucide-react';
+import {
+  SUPPORTED_SUB_ADDRESS_DELIMITERS,
+  isSupportedSubAddressDelimiter,
+  isValidSubAddressDelimiter,
+} from '@/lib/sub-addressing';
+
+const CUSTOM_DELIMITER_SENTINEL = '__custom__';
+const DEFAULT_CUSTOM_DELIMITER = '~';
 
 export function ComposingSettings() {
   const t = useTranslations('settings.email_behavior');
@@ -17,6 +25,7 @@ export function ComposingSettings() {
     autoSelectReplyIdentity,
     attachmentReminderEnabled,
     attachmentReminderKeywords,
+    subAddressDelimiter,
     updateSetting,
   } = useSettingsStore();
 
@@ -40,6 +49,49 @@ export function ComposingSettings() {
         />
       </SettingItem>
 
+      <SettingItem
+        label={t('sub_address_delimiter.label')}
+        description={t('sub_address_delimiter.description', { delimiter: subAddressDelimiter })}
+      >
+        <div className="flex flex-col items-end gap-2">
+          <Select
+            value={isSupportedSubAddressDelimiter(subAddressDelimiter) ? subAddressDelimiter : CUSTOM_DELIMITER_SENTINEL}
+            onChange={(value) => {
+              if (value === CUSTOM_DELIMITER_SENTINEL) {
+                if (isSupportedSubAddressDelimiter(subAddressDelimiter)) {
+                  updateSetting('subAddressDelimiter', DEFAULT_CUSTOM_DELIMITER);
+                }
+              } else {
+                updateSetting('subAddressDelimiter', value);
+              }
+            }}
+            options={[
+              ...SUPPORTED_SUB_ADDRESS_DELIMITERS.map((delim) => ({
+                value: delim,
+                label: t('sub_address_delimiter.option', { delimiter: delim }),
+              })),
+              { value: CUSTOM_DELIMITER_SENTINEL, label: t('sub_address_delimiter.custom') },
+            ]}
+          />
+          {!isSupportedSubAddressDelimiter(subAddressDelimiter) && (
+            <input
+              type="text"
+              maxLength={1}
+              value={subAddressDelimiter}
+              onChange={(e) => {
+                const next = e.target.value.slice(0, 1);
+                if (next && isValidSubAddressDelimiter(next)) {
+                  updateSetting('subAddressDelimiter', next);
+                }
+              }}
+              aria-label={t('sub_address_delimiter.custom_input_label')}
+              placeholder={DEFAULT_CUSTOM_DELIMITER}
+              className="w-16 px-2 py-1 text-sm font-mono text-center bg-background border border-border rounded-md focus:outline-none focus:ring-1 focus:ring-ring"
+            />
+          )}
+        </div>
+      </SettingItem>
+
       <SettingItem label={t('attachment_reminder.label')} description={t('attachment_reminder.description')}>
         <ToggleSwitch
           checked={attachmentReminderEnabled}

components/settings/notification-settings.tsx

@@ -1,13 +1,32 @@
 "use client";
 
+import { useEffect, useState } from 'react';
 import { useTranslations } from 'next-intl';
 import { useSettingsStore } from '@/stores/settings-store';
 import { SettingsSection, SettingItem, ToggleSwitch, Select } from './settings-section';
 import { playNotificationSound, NOTIFICATION_SOUNDS } from '@/lib/notification-sound';
 import type { NotificationSoundChoice } from '@/lib/notification-sound';
 import { Button } from '@/components/ui/button';
-import { Volume2 } from 'lucide-react';
+import { CheckCircle2, Volume2, XCircle } from 'lucide-react';
 import { usePolicyStore } from '@/stores/policy-store';
+import { useAuthStore } from '@/stores/auth-store';
+import { ConfirmDialog } from '@/components/ui/confirm-dialog';
+import { useConfirmDialog } from '@/hooks/use-confirm-dialog';
+import {
+  DEFAULT_RELAY_BASE_URL,
+  WebPushUnsupportedError,
+  disableWebPush,
+  enableWebPush,
+  isWebPushEnabled,
+  isWebPushSupported,
+} from '@/lib/web-push';
+
+type PushStatus =
+  | { kind: 'idle' }
+  | { kind: 'busy' }
+  | { kind: 'enabled' }
+  | { kind: 'unsupported' }
+  | { kind: 'error'; message: string };
 
 export function NotificationSettings() {
   const t = useTranslations('settings.notifications');
@@ -21,6 +40,77 @@ export function NotificationSettings() {
     updateSetting,
   } = useSettingsStore();
   const { isSettingLocked, isSettingHidden } = usePolicyStore();
+  const client = useAuthStore((s) => s.client);
+  const username = useAuthStore((s) => s.username);
+  const { dialogProps: confirmDialogProps, confirm: confirmDialog } = useConfirmDialog();
+
+  const supported = typeof window !== 'undefined' && isWebPushSupported();
+  const [relayUrl, setRelayUrl] = useState(DEFAULT_RELAY_BASE_URL);
+  const [pushStatus, setPushStatus] = useState<PushStatus>(
+    supported ? { kind: 'idle' } : { kind: 'unsupported' },
+  );
+
+  useEffect(() => {
+    if (!supported) return;
+    void (async () => {
+      const enabled = await isWebPushEnabled();
+      if (enabled) setPushStatus({ kind: 'enabled' });
+    })();
+  }, [supported]);
+
+  const trimmedRelay = relayUrl.trim().replace(/\/+$/, '');
+  const isValidRelay = /^https?:\/\/.+/i.test(trimmedRelay);
+  const busy = pushStatus.kind === 'busy';
+
+  const handleEnablePush = async () => {
+    if (!client) {
+      setPushStatus({ kind: 'error', message: 'Sign in first' });
+      return;
+    }
+    if (!isValidRelay) {
+      setPushStatus({ kind: 'error', message: 'Enter a valid https:// URL' });
+      return;
+    }
+    setPushStatus({ kind: 'busy' });
+    try {
+      await enableWebPush({
+        client,
+        relayBaseUrl: trimmedRelay,
+        accountLabel: username ?? undefined,
+      });
+      setPushStatus({ kind: 'enabled' });
+    } catch (err) {
+      if (err instanceof WebPushUnsupportedError) {
+        setPushStatus({ kind: 'unsupported' });
+        return;
+      }
+      setPushStatus({
+        kind: 'error',
+        message: err instanceof Error ? err.message : 'Failed to enable push',
+      });
+    }
+  };
+
+  const handleDisablePush = async () => {
+    if (!client) return;
+    const confirmed = await confirmDialog({
+      title: t('push.confirm_disable_title'),
+      message: t('push.confirm_disable_message'),
+      confirmText: t('push.disable'),
+      variant: 'destructive',
+    });
+    if (!confirmed) return;
+    setPushStatus({ kind: 'busy' });
+    try {
+      await disableWebPush({ client, relayBaseUrl: trimmedRelay });
+      setPushStatus({ kind: 'idle' });
+    } catch (err) {
+      setPushStatus({
+        kind: 'error',
+        message: err instanceof Error ? err.message : 'Failed to disable push',
+      });
+    }
+  };
 
   const soundOptions = NOTIFICATION_SOUNDS.map((s) => ({
     value: s.id,
@@ -29,6 +119,46 @@ export function NotificationSettings() {
 
   return (
     <div className="space-y-8">
+      <SettingsSection title={t('push.title')} description={t('push.description')}>
+        <div className="rounded-md border p-4 space-y-3">
+          <div className="flex items-center justify-between gap-3">
+            <label className="text-sm font-medium" htmlFor="push-relay-url">
+              {t('push.relay_label')}
+            </label>
+            <PushStatusBadge status={pushStatus} t={t} />
+          </div>
+          <p className="text-xs text-muted-foreground">{t('push.relay_desc')}</p>
+          <input
+            id="push-relay-url"
+            type="url"
+            inputMode="url"
+            autoComplete="off"
+            spellCheck={false}
+            value={relayUrl}
+            onChange={(e) => setRelayUrl(e.target.value)}
+            placeholder={t('push.relay_placeholder')}
+            disabled={busy || pushStatus.kind === 'unsupported'}
+            className="w-full rounded border bg-background px-3 py-2 text-sm disabled:opacity-50"
+          />
+          <div className="flex flex-wrap gap-2">
+            <Button
+              onClick={handleEnablePush}
+              disabled={busy || pushStatus.kind === 'unsupported' || !isValidRelay || !client}
+            >
+              {pushStatus.kind === 'enabled' ? t('push.reenable') : t('push.enable')}
+            </Button>
+            {pushStatus.kind === 'enabled' && (
+              <Button variant="outline" onClick={handleDisablePush} disabled={busy}>
+                {t('push.disable')}
+              </Button>
+            )}
+          </div>
+          {pushStatus.kind === 'unsupported' && (
+            <p className="text-xs text-muted-foreground">{t('push.ios_hint')}</p>
+          )}
+        </div>
+      </SettingsSection>
+
       <SettingsSection title={t('sound_selection.title')} description={t('sound_selection.description')}>
         <SettingItem
           label={t('sound_selection.choose')}
@@ -118,6 +248,45 @@ export function NotificationSettings() {
           />
         </SettingItem>
       </SettingsSection>
+
+      <ConfirmDialog {...confirmDialogProps} />
     </div>
   );
 }
+
+function PushStatusBadge({
+  status,
+  t,
+}: {
+  status: PushStatus;
+  t: ReturnType<typeof useTranslations>;
+}) {
+  if (status.kind === 'enabled') {
+    return (
+      <span className="inline-flex items-center gap-1 text-xs text-emerald-600 dark:text-emerald-400">
+        <CheckCircle2 className="w-3.5 h-3.5" />
+        {t('push.status_active')}
+      </span>
+    );
+  }
+  if (status.kind === 'busy') {
+    return <span className="text-xs text-muted-foreground">{t('push.status_busy')}</span>;
+  }
+  if (status.kind === 'unsupported') {
+    return (
+      <span className="inline-flex items-center gap-1 text-xs text-muted-foreground">
+        <XCircle className="w-3.5 h-3.5" />
+        {t('push.status_unsupported')}
+      </span>
+    );
+  }
+  if (status.kind === 'error') {
+    return (
+      <span className="inline-flex items-center gap-1 text-xs text-destructive" title={status.message}>
+        <XCircle className="w-3.5 h-3.5" />
+        {status.message}
+      </span>
+    );
+  }
+  return <span className="text-xs text-muted-foreground">{t('push.status_inactive')}</span>;
+}

components/settings/share-collection-dialog.tsx

@@ -0,0 +1,347 @@
+"use client";
+
+import { useEffect, useMemo, useRef, useState } from "react";
+import { useTranslations } from "next-intl";
+import { Button } from "@/components/ui/button";
+import { X, Loader2, UserPlus, Trash2, Users, ChevronDown } from "lucide-react";
+import type { IJMAPClient } from "@/lib/jmap/client-interface";
+import type { Principal, CalendarRights, AddressBookRights } from "@/lib/jmap/types";
+import { toast } from "@/stores/toast-store";
+
+type ShareKind = "calendar" | "addressBook";
+type AnyRights = CalendarRights | AddressBookRights;
+
+type RolePreset = "freeBusy" | "read" | "readWrite" | "manager" | "custom";
+
+const CALENDAR_PRESETS: Record<Exclude<RolePreset, "custom">, CalendarRights> = {
+  freeBusy: {
+    mayReadFreeBusy: true, mayReadItems: false, mayWriteAll: false, mayWriteOwn: false,
+    mayUpdatePrivate: false, mayRSVP: false, mayShare: false, mayDelete: false,
+  },
+  read: {
+    mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: false, mayWriteOwn: false,
+    mayUpdatePrivate: false, mayRSVP: false, mayShare: false, mayDelete: false,
+  },
+  readWrite: {
+    mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true,
+    mayUpdatePrivate: true, mayRSVP: true, mayShare: false, mayDelete: false,
+  },
+  manager: {
+    mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true,
+    mayUpdatePrivate: true, mayRSVP: true, mayShare: true, mayDelete: true,
+  },
+};
+
+const ADDRESS_BOOK_PRESETS: Record<Exclude<RolePreset, "custom" | "freeBusy">, AddressBookRights> = {
+  read: { mayRead: true, mayWrite: false, mayShare: false, mayDelete: false },
+  readWrite: { mayRead: true, mayWrite: true, mayShare: false, mayDelete: false },
+  manager: { mayRead: true, mayWrite: true, mayShare: true, mayDelete: true },
+};
+
+function detectCalendarPreset(r: CalendarRights): RolePreset {
+  for (const [name, preset] of Object.entries(CALENDAR_PRESETS) as [Exclude<RolePreset, "custom">, CalendarRights][]) {
+    if ((Object.keys(preset) as (keyof CalendarRights)[]).every((k) => preset[k] === r[k])) {
+      return name;
+    }
+  }
+  return "custom";
+}
+
+function detectAddressBookPreset(r: AddressBookRights): RolePreset {
+  for (const [name, preset] of Object.entries(ADDRESS_BOOK_PRESETS) as [Exclude<RolePreset, "custom" | "freeBusy">, AddressBookRights][]) {
+    const keys = Object.keys(preset) as (keyof AddressBookRights)[];
+    if (keys.every((k) => preset[k] === (r[k] ?? false))) {
+      return name;
+    }
+  }
+  return "custom";
+}
+
+interface ShareCollectionDialogProps {
+  client: IJMAPClient;
+  kind: ShareKind;
+  collectionName: string;
+  shareWith: Record<string, AnyRights> | null | undefined;
+  ownAccountId: string;
+  onShare: (principalId: string, rights: AnyRights | null) => Promise<void>;
+  onClose: () => void;
+}
+
+export function ShareCollectionDialog({
+  client,
+  kind,
+  collectionName,
+  shareWith,
+  ownAccountId,
+  onShare,
+  onClose,
+}: ShareCollectionDialogProps) {
+  const t = useTranslations("sharing");
+  const tCommon = useTranslations("common");
+  const modalRef = useRef<HTMLDivElement>(null);
+  const [principals, setPrincipals] = useState<Principal[]>([]);
+  const [loadingPrincipals, setLoadingPrincipals] = useState(true);
+  const [search, setSearch] = useState("");
+  const [savingId, setSavingId] = useState<string | null>(null);
+  const [showAdd, setShowAdd] = useState(false);
+
+  // Load principals on mount
+  useEffect(() => {
+    let cancelled = false;
+    setLoadingPrincipals(true);
+    client.getPrincipals().then((list) => {
+      if (cancelled) return;
+      // Exclude the user themselves and any principal that already has a share
+      const existing = new Set(Object.keys(shareWith || {}));
+      const filtered = list.filter((p) => p.id !== ownAccountId && !existing.has(p.id));
+      setPrincipals(filtered);
+      setLoadingPrincipals(false);
+    }).catch(() => {
+      if (!cancelled) setLoadingPrincipals(false);
+    });
+    return () => { cancelled = true; };
+  }, [client, ownAccountId, shareWith]);
+
+  // Map principal id -> Principal for displayed shares
+  const allPrincipalsById = useMemo(() => {
+    const map = new Map<string, Principal>();
+    for (const p of principals) map.set(p.id, p);
+    return map;
+  }, [principals]);
+
+  // Close on Escape, focus trap, click outside
+  useEffect(() => {
+    const onKey = (e: KeyboardEvent) => {
+      if (e.key === "Escape") onClose();
+    };
+    document.addEventListener("keydown", onKey);
+    return () => document.removeEventListener("keydown", onKey);
+  }, [onClose]);
+
+  const handleSetRights = async (principalId: string, preset: RolePreset) => {
+    if (preset === "custom") return; // custom is read-only here
+    const rights = kind === "calendar"
+      ? CALENDAR_PRESETS[preset as keyof typeof CALENDAR_PRESETS]
+      : ADDRESS_BOOK_PRESETS[preset as keyof typeof ADDRESS_BOOK_PRESETS];
+    if (!rights) return;
+    setSavingId(principalId);
+    try {
+      await onShare(principalId, rights);
+      toast.success(t("share_updated"));
+    } catch (err) {
+      toast.error(err instanceof Error ? err.message : t("share_failed"));
+    } finally {
+      setSavingId(null);
+    }
+  };
+
+  const handleRemove = async (principalId: string) => {
+    setSavingId(principalId);
+    try {
+      await onShare(principalId, null);
+      toast.success(t("share_removed"));
+    } catch (err) {
+      toast.error(err instanceof Error ? err.message : t("share_failed"));
+    } finally {
+      setSavingId(null);
+    }
+  };
+
+  const handleAdd = async (principal: Principal) => {
+    const defaultPreset: RolePreset = "read";
+    const rights = kind === "calendar"
+      ? CALENDAR_PRESETS[defaultPreset]
+      : ADDRESS_BOOK_PRESETS[defaultPreset];
+    setSavingId(principal.id);
+    try {
+      await onShare(principal.id, rights);
+      // Move principal out of the "to add" list
+      setPrincipals((prev) => prev.filter((p) => p.id !== principal.id));
+      setShowAdd(false);
+      setSearch("");
+      toast.success(t("share_added"));
+    } catch (err) {
+      toast.error(err instanceof Error ? err.message : t("share_failed"));
+    } finally {
+      setSavingId(null);
+    }
+  };
+
+  const filteredPrincipals = useMemo(() => {
+    const q = search.trim().toLowerCase();
+    if (!q) return principals;
+    return principals.filter((p) =>
+      p.name.toLowerCase().includes(q) ||
+      p.email?.toLowerCase().includes(q) ||
+      p.description?.toLowerCase().includes(q)
+    );
+  }, [principals, search]);
+
+  const sharedEntries = useMemo(() => {
+    return Object.entries(shareWith || {}) as [string, AnyRights][];
+  }, [shareWith]);
+
+  const presetOptions = kind === "calendar"
+    ? ["freeBusy", "read", "readWrite", "manager"] as const
+    : ["read", "readWrite", "manager"] as const;
+
+  return (
+    <div className="fixed inset-0 z-50 flex items-center justify-center">
+      <div className="absolute inset-0 bg-black/50 backdrop-blur-[1px]" onClick={onClose} aria-hidden="true" />
+      <div
+        ref={modalRef}
+        role="dialog"
+        aria-modal="true"
+        aria-label={t("title", { name: collectionName })}
+        className="relative bg-background border border-border rounded-lg shadow-xl w-full max-w-lg mx-4 animate-in zoom-in-95 duration-200 max-h-[85vh] flex flex-col"
+      >
+        <div className="flex items-center justify-between px-6 py-4 border-b border-border">
+          <div className="flex items-center gap-2">
+            <Users className="w-5 h-5 text-primary" />
+            <h2 className="text-lg font-semibold">{t("title", { name: collectionName })}</h2>
+          </div>
+          <button
+            onClick={onClose}
+            className="p-1.5 rounded-md hover:bg-muted transition-colors duration-150 text-muted-foreground hover:text-foreground"
+            aria-label={tCommon("close")}
+          >
+            <X className="w-5 h-5" />
+          </button>
+        </div>
+
+        <div className="px-6 py-4 space-y-4 overflow-y-auto">
+          <p className="text-sm text-muted-foreground">{t("description")}</p>
+
+          {sharedEntries.length === 0 && !showAdd && (
+            <div className="text-sm text-muted-foreground italic py-4 text-center">
+              {t("no_shares")}
+            </div>
+          )}
+
+          {sharedEntries.length > 0 && (
+            <ul className="divide-y divide-border rounded-md border border-border overflow-hidden">
+              {sharedEntries.map(([principalId, rights]) => {
+                const principal = allPrincipalsById.get(principalId);
+                const preset = kind === "calendar"
+                  ? detectCalendarPreset(rights as CalendarRights)
+                  : detectAddressBookPreset(rights as AddressBookRights);
+                return (
+                  <li key={principalId} className="flex items-center gap-3 px-3 py-2.5">
+                    <div className="flex-1 min-w-0">
+                      <div className="text-sm font-medium truncate">
+                        {principal?.name || principal?.email || principalId}
+                      </div>
+                      {principal?.description && (
+                        <div className="text-xs text-muted-foreground truncate">
+                          {principal.description}
+                        </div>
+                      )}
+                    </div>
+                    <div className="relative">
+                      <select
+                        value={preset}
+                        onChange={(e) => handleSetRights(principalId, e.target.value as RolePreset)}
+                        disabled={savingId === principalId}
+                        className="appearance-none rounded-md border border-input bg-background pl-3 pr-8 py-1.5 text-xs focus:outline-none focus:ring-2 focus:ring-ring disabled:opacity-50"
+                      >
+                        {presetOptions.map((p) => (
+                          <option key={p} value={p}>{t(`preset.${p}`)}</option>
+                        ))}
+                        {preset === "custom" && (
+                          <option value="custom">{t("preset.custom")}</option>
+                        )}
+                      </select>
+                      <ChevronDown className="w-3 h-3 absolute right-2 top-1/2 -translate-y-1/2 pointer-events-none text-muted-foreground" />
+                    </div>
+                    <button
+                      onClick={() => handleRemove(principalId)}
+                      disabled={savingId === principalId}
+                      className="p-1.5 rounded-md hover:bg-destructive/10 text-muted-foreground hover:text-destructive transition-colors disabled:opacity-50"
+                      aria-label={t("remove")}
+                      title={t("remove")}
+                    >
+                      {savingId === principalId
+                        ? <Loader2 className="w-4 h-4 animate-spin" />
+                        : <Trash2 className="w-4 h-4" />}
+                    </button>
+                  </li>
+                );
+              })}
+            </ul>
+          )}
+
+          {!showAdd && (
+            <Button
+              variant="outline"
+              onClick={() => setShowAdd(true)}
+              className="w-full"
+            >
+              <UserPlus className="w-4 h-4 mr-2" />
+              {t("add_person")}
+            </Button>
+          )}
+
+          {showAdd && (
+            <div className="space-y-2 border border-border rounded-md p-3">
+              <input
+                type="text"
+                value={search}
+                onChange={(e) => setSearch(e.target.value)}
+                placeholder={t("search_placeholder")}
+                className="w-full rounded-md border border-input bg-background px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-ring"
+                autoFocus
+              />
+              <div className="max-h-48 overflow-y-auto -mx-1">
+                {loadingPrincipals && (
+                  <div className="flex items-center justify-center py-4 text-muted-foreground">
+                    <Loader2 className="w-4 h-4 animate-spin mr-2" />
+                    {t("loading_principals")}
+                  </div>
+                )}
+                {!loadingPrincipals && filteredPrincipals.length === 0 && (
+                  <div className="text-xs text-muted-foreground text-center py-3">
+                    {search.trim() ? t("no_match") : t("no_principals")}
+                  </div>
+                )}
+                {!loadingPrincipals && filteredPrincipals.map((p) => (
+                  <button
+                    key={p.id}
+                    onClick={() => handleAdd(p)}
+                    disabled={savingId === p.id}
+                    className="w-full text-left px-3 py-2 rounded-md hover:bg-muted disabled:opacity-50 transition-colors"
+                  >
+                    <div className="flex items-center gap-2">
+                      <div className="flex-1 min-w-0">
+                        <div className="text-sm font-medium truncate flex items-center gap-2">
+                          {p.name}
+                          {p.type === "group" && (
+                            <span className="text-[10px] uppercase font-normal text-muted-foreground bg-muted rounded px-1 py-0.5">
+                              {t("group")}
+                            </span>
+                          )}
+                        </div>
+                        {p.email && p.email !== p.name && (
+                          <div className="text-xs text-muted-foreground truncate">{p.email}</div>
+                        )}
+                      </div>
+                      {savingId === p.id && <Loader2 className="w-4 h-4 animate-spin" />}
+                    </div>
+                  </button>
+                ))}
+              </div>
+              <div className="flex justify-end pt-1">
+                <Button variant="ghost" size="sm" onClick={() => { setShowAdd(false); setSearch(""); }}>
+                  {tCommon("cancel")}
+                </Button>
+              </div>
+            </div>
+          )}
+        </div>
+
+        <div className="flex items-center justify-end gap-2 px-6 py-4 border-t border-border">
+          <Button onClick={onClose}>{tCommon("close")}</Button>
+        </div>
+      </div>
+    </div>
+  );
+}

components/ui/flag-icons.tsx

@@ -152,6 +152,18 @@ export function FlagRU(props: FlagProps) {
   );
 }
 
+/** Turkey - Red with white crescent and star */
+export function FlagTR(props: FlagProps) {
+  return (
+    <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 30 20" width={W} height={H} className={flagClass} {...props}>
+      <rect width="30" height="20" fill="#E30A17" />
+      <circle cx="10" cy="10" r="6" fill="#fff" />
+      <circle cx="11.5" cy="10" r="5" fill="#E30A17" />
+      <polygon points="19.5,7.8 19.994,9.32 21.592,9.32 20.299,10.26 20.793,11.78 19.5,10.84 18.207,11.78 18.701,10.26 17.408,9.32 19.006,9.32" fill="#fff" />
+    </svg>
+  );
+}
+
 /** Ukraine – Blue, Yellow horizontal */
 export function FlagUA(props: FlagProps) {
   return (
@@ -192,6 +204,7 @@ export const flagComponents: Record<string, (props: FlagProps) => ReactElement>
   pl: FlagPL,
   pt: FlagBR,
   ru: FlagRU,
+  tr: FlagTR,
   uk: FlagUA,
   zh: FlagCN,
 };

components/ui/language-switcher.tsx

@@ -8,6 +8,7 @@ import { cn } from '@/lib/utils';
 import { flagComponents } from './flag-icons';
 
 const languages = [
+  { value: 'cs', label: 'Česky' },
   { value: 'en', label: 'English' },
   { value: 'fr', label: 'Français' },
   { value: 'ja', label: '日本語' },
@@ -20,6 +21,7 @@ const languages = [
   { value: 'pl', label: 'Polski' },
   { value: 'pt', label: 'Português' },
   { value: 'ru', label: 'Русский' },
+  { value: 'tr', label: 'Türkçe' },
   { value: 'uk', label: 'Українська' },
   { value: 'zh', label: '简体中文' },
 ];

docker-compose.yml

@@ -8,6 +8,14 @@ services:
       - PORT=3000
     env_file:
       - .env.local
+    volumes:
+      # Encrypted user settings (SETTINGS_DATA_DIR).
+      - bulwark-settings:/app/data/settings
+      # Admin dashboard state: config, password hash, plugins, audit logs (ADMIN_DATA_DIR).
+      - bulwark-admin:/app/data/admin
+      # Anonymous telemetry: instance id, consent state, login HMACs (TELEMETRY_DATA_DIR).
+      # Persisting this preserves the admin's consent choice and stable instance id across upgrades.
+      - bulwark-telemetry:/app/data/telemetry
     healthcheck:
       test:
         [
@@ -23,3 +31,8 @@ services:
       retries: 3
       start_period: 10s
     restart: unless-stopped
+
+volumes:
+  bulwark-settings:
+  bulwark-admin:
+  bulwark-telemetry:

hooks/use-format-event-date.ts

@@ -0,0 +1,27 @@
+import { useCallback } from "react";
+import { useTranslations } from "next-intl";
+import { format } from "date-fns";
+
+/**
+ * Returns a memoized function that formats a calendar event date
+ * using the current locale for day and month names.
+ * 
+ * The string will be in the format: "EEE, MMM d, yyyy"
+ * 
+ * For example: "Wed, Apr 29, 2026" (en)
+ *              "Qua, Abr 29, 2026" (pt)
+ */
+export function useFormatEventDate(): (date: Date) => string {
+  const t = useTranslations("calendar");
+
+  return useCallback(
+    (date: Date): string => {
+      const dayOfWeek = format(date, "EEE").toLowerCase();
+      const month = format(date, "MMM").toLowerCase();
+      const day = format(date, "d");
+      const year = format(date, "yyyy");
+      return `${t(`days.${dayOfWeek}`)}, ${t(`months.${month}`)} ${day}, ${year}`;
+    },
+    [t]
+  );
+}

hooks/use-keyboard-shortcuts.ts

@@ -39,6 +39,7 @@ export interface UseKeyboardShortcutsOptions {
   enabled?: boolean;
   emails: Email[];
   selectedEmailId?: string;
+  selectionCount?: number;
   handlers: KeyboardShortcutHandlers;
 }
 
@@ -58,6 +59,7 @@ export function useKeyboardShortcuts({
   enabled = true,
   emails,
   selectedEmailId,
+  selectionCount = 0,
   handlers,
 }: UseKeyboardShortcutsOptions) {
   const handlersRef = useRef(handlers);
@@ -90,6 +92,8 @@ export function useKeyboardShortcuts({
       // Shortcuts that should NOT work with modifiers
       if (hasModifier) return;
 
+      const hasBatchTarget = !!selectedEmailId || selectionCount > 0;
+
       switch (key) {
         // Navigation
         case "j":
@@ -152,7 +156,7 @@ export function useKeyboardShortcuts({
           break;
 
         case "e":
-          if (selectedEmailId) {
+          if (hasBatchTarget) {
             event.preventDefault();
             h.onArchive?.();
           }
@@ -161,28 +165,28 @@ export function useKeyboardShortcuts({
         case "#":
         case "delete":
         case "backspace":
-          if (selectedEmailId && (key === "#" || key === "delete" || key === "backspace")) {
+          if (hasBatchTarget) {
             event.preventDefault();
             h.onDelete?.();
           }
           break;
 
         case "u":
-          if (selectedEmailId) {
+          if (hasBatchTarget) {
             event.preventDefault();
             h.onMarkAsUnread?.();
           }
           break;
 
         case "i":
-          if (selectedEmailId && event.shiftKey) {
+          if (hasBatchTarget && event.shiftKey) {
             event.preventDefault();
             h.onMarkAsRead?.();
           }
           break;
 
         case "!":
-          if (selectedEmailId) {
+          if (hasBatchTarget) {
             event.preventDefault();
             h.onToggleSpam?.();
           }
@@ -220,7 +224,7 @@ export function useKeyboardShortcuts({
           break;
       }
     },
-    [selectedEmailId]
+    [selectedEmailId, selectionCount]
   );
 
   useEffect(() => {

hooks/use-time-grid-interactions.ts

@@ -80,6 +80,7 @@ export function useTimeGridInteractions({
     dayDate: Date,
   ) => {
     if (isMobile) return;
+    if (e.pointerType === "touch") return;
     if (e.button !== 0) return;
     if ((e.target as HTMLElement).closest("[data-calendar-event], [data-resize-handle]")) return;
 

i18n/request.ts

@@ -11,6 +11,9 @@ export default getRequestConfig(async ({ requestLocale }) => {
   // Use static imports for better compatibility
   let messages;
   switch (locale) {
+    case 'cs':
+      messages = (await import('../locales/cs/common.json')).default;
+      break;
     case 'fr':
       messages = (await import('../locales/fr/common.json')).default;
       break;
@@ -44,6 +47,9 @@ export default getRequestConfig(async ({ requestLocale }) => {
     case 'ru':
       messages = (await import('../locales/ru/common.json')).default;
       break;
+    case 'tr':
+      messages = (await import('../locales/tr/common.json')).default;
+      break;
     case 'uk':
       messages = (await import('../locales/uk/common.json')).default;
       break;

i18n/routing.ts

@@ -13,7 +13,7 @@ const localePrefix = (process.env.NEXT_PUBLIC_LOCALE_PREFIX ?? 'never') as
   | 'as-needed';
 
 export const routing = defineRouting({
-  locales: ['en', 'fr', 'de', 'es', 'it', 'ja', 'ko', 'lv', 'nl', 'pl', 'pt', 'ru', 'uk', 'zh'],
+  locales: ['cs', 'en', 'fr', 'de', 'es', 'it', 'ja', 'ko', 'lv', 'nl', 'pl', 'pt', 'ru', 'tr', 'uk', 'zh'],
   defaultLocale: 'en',
   localePrefix
 });

instrumentation.node.ts

@@ -51,6 +51,14 @@ configManager.load()
   .then(() => {
     console.info("Admin dashboard initialized");
   })
+  .then(async () => {
+    // Anonymous telemetry - on by default. Admins can disable via the
+    // admin UI, the BULWARK_TELEMETRY env var, or by clearing the endpoint.
+    // See https://bulwarkmail.org/docs/legal/privacy/telemetry
+    const { startScheduler, markProcessStart } = await import("./lib/telemetry");
+    markProcessStart();
+    await startScheduler();
+  })
   .catch((err) => {
     console.warn("Admin dashboard init skipped:", err instanceof Error ? err.message : err);
   });

lib/__tests__/calendar-alerts.test.ts

@@ -82,7 +82,7 @@ function makeCalendar(overrides: Partial<Calendar> = {}): Calendar {
       mayWriteOwn: true,
       mayUpdatePrivate: true,
       mayRSVP: true,
-      mayAdmin: false,
+      mayShare: false,
       mayDelete: false,
     },
     ...overrides,

lib/__tests__/csp-frame-origins.test.ts

@@ -0,0 +1,104 @@
+import { describe, expect, it } from 'vitest';
+import {
+  isValidFrameOrigin,
+  sanitizeFrameOrigins,
+} from '@/lib/admin/csp-frame-origins';
+
+describe('isValidFrameOrigin', () => {
+  it('accepts plain https origins', () => {
+    expect(isValidFrameOrigin('https://www.youtube-nocookie.com')).toBe(true);
+    expect(isValidFrameOrigin('https://meet.example.com')).toBe(true);
+    expect(isValidFrameOrigin('https://a.b.c.example.com')).toBe(true);
+  });
+
+  it('accepts a wildcard subdomain', () => {
+    expect(isValidFrameOrigin('https://*.example.com')).toBe(true);
+    expect(isValidFrameOrigin('https://*.youtube.com')).toBe(true);
+  });
+
+  it('accepts an explicit port', () => {
+    expect(isValidFrameOrigin('https://meet.example.com:8443')).toBe(true);
+    expect(isValidFrameOrigin('https://*.example.com:443')).toBe(true);
+  });
+
+  it('rejects non-https schemes', () => {
+    expect(isValidFrameOrigin('http://example.com')).toBe(false);
+    expect(isValidFrameOrigin('ftp://example.com')).toBe(false);
+    expect(isValidFrameOrigin('data:text/html,foo')).toBe(false);
+    expect(isValidFrameOrigin('javascript:alert(1)')).toBe(false);
+  });
+
+  it('rejects bare schemes and wildcard hosts', () => {
+    expect(isValidFrameOrigin('https://')).toBe(false);
+    expect(isValidFrameOrigin('https://*')).toBe(false);
+    expect(isValidFrameOrigin('https://*.com')).toBe(false);
+    expect(isValidFrameOrigin('https://localhost')).toBe(false);
+  });
+
+  it('rejects paths, queries, and fragments', () => {
+    expect(isValidFrameOrigin('https://example.com/embed')).toBe(false);
+    expect(isValidFrameOrigin('https://example.com/')).toBe(false);
+    expect(isValidFrameOrigin('https://example.com?x=1')).toBe(false);
+    expect(isValidFrameOrigin('https://example.com#x')).toBe(false);
+  });
+
+  it('rejects userinfo, IPs, and IPv6', () => {
+    expect(isValidFrameOrigin('https://user:pass@example.com')).toBe(false);
+    expect(isValidFrameOrigin('https://1.2.3.4')).toBe(false);
+    expect(isValidFrameOrigin('https://[::1]')).toBe(false);
+  });
+
+  it('rejects values that try to break out of the directive', () => {
+    expect(isValidFrameOrigin("https://example.com'; script-src 'unsafe-eval")).toBe(false);
+    expect(isValidFrameOrigin('https://example.com" data:')).toBe(false);
+    expect(isValidFrameOrigin('https://example.com data:')).toBe(false);
+    expect(isValidFrameOrigin('https://example.com\nhttps://evil.com')).toBe(false);
+    expect(isValidFrameOrigin('https://example.com;https://evil.com')).toBe(false);
+    expect(isValidFrameOrigin('https://exa,mple.com')).toBe(false);
+  });
+
+  it('rejects non-strings and obvious garbage', () => {
+    expect(isValidFrameOrigin(undefined)).toBe(false);
+    expect(isValidFrameOrigin(null)).toBe(false);
+    expect(isValidFrameOrigin(42)).toBe(false);
+    expect(isValidFrameOrigin('')).toBe(false);
+    expect(isValidFrameOrigin('not-a-url')).toBe(false);
+    expect(isValidFrameOrigin('a'.repeat(300))).toBe(false);
+  });
+});
+
+describe('sanitizeFrameOrigins', () => {
+  it('returns empty for non-array input', () => {
+    expect(sanitizeFrameOrigins(undefined)).toEqual([]);
+    expect(sanitizeFrameOrigins(null)).toEqual([]);
+    expect(sanitizeFrameOrigins('https://example.com')).toEqual([]);
+    expect(sanitizeFrameOrigins({})).toEqual([]);
+  });
+
+  it('keeps valid entries and drops invalid ones silently', () => {
+    expect(
+      sanitizeFrameOrigins([
+        'https://www.youtube-nocookie.com',
+        'http://insecure.com',
+        'https://meet.example.com:8443',
+        'https://example.com/path',
+        42,
+        'https://*.vimeo.com',
+      ]),
+    ).toEqual([
+      'https://www.youtube-nocookie.com',
+      'https://meet.example.com:8443',
+      'https://*.vimeo.com',
+    ]);
+  });
+
+  it('dedupes case-insensitively', () => {
+    expect(
+      sanitizeFrameOrigins([
+        'https://Example.com',
+        'https://example.com',
+        'https://EXAMPLE.com',
+      ]),
+    ).toEqual(['https://Example.com']);
+  });
+});

lib/__tests__/email-threading.test.ts

@@ -0,0 +1,86 @@
+import { describe, it, expect } from 'vitest';
+import {
+  computeReplyThreadingHeaders,
+  stripMessageIdBrackets,
+} from '../email-threading';
+
+describe('stripMessageIdBrackets', () => {
+  it('strips surrounding angle brackets', () => {
+    expect(stripMessageIdBrackets('<abc@example.com>')).toBe('abc@example.com');
+  });
+
+  it('handles whitespace and missing brackets', () => {
+    expect(stripMessageIdBrackets('  abc@example.com  ')).toBe('abc@example.com');
+    expect(stripMessageIdBrackets('<abc@example.com')).toBe('abc@example.com');
+    expect(stripMessageIdBrackets('abc@example.com>')).toBe('abc@example.com');
+  });
+});
+
+describe('computeReplyThreadingHeaders', () => {
+  it('returns null when the parent has no Message-ID', () => {
+    expect(computeReplyThreadingHeaders(undefined)).toBeNull();
+    expect(computeReplyThreadingHeaders({})).toBeNull();
+    expect(computeReplyThreadingHeaders({ messageId: '' })).toBeNull();
+    expect(computeReplyThreadingHeaders({ messageId: '   ' })).toBeNull();
+  });
+
+  it('sets In-Reply-To to the parent Message-ID and seeds References with it', () => {
+    const result = computeReplyThreadingHeaders({
+      messageId: '<root@example.com>',
+    });
+    expect(result).toEqual({
+      inReplyTo: ['root@example.com'],
+      references: ['root@example.com'],
+    });
+  });
+
+  it('appends the parent to existing References per RFC 5322', () => {
+    const result = computeReplyThreadingHeaders({
+      messageId: '<msg-2@example.com>',
+      references: ['<msg-0@example.com>', '<msg-1@example.com>'],
+    });
+    expect(result).toEqual({
+      inReplyTo: ['msg-2@example.com'],
+      references: ['msg-0@example.com', 'msg-1@example.com', 'msg-2@example.com'],
+    });
+  });
+
+  it('de-duplicates if the parent already appears in References', () => {
+    const result = computeReplyThreadingHeaders({
+      messageId: '<msg-1@example.com>',
+      references: ['<msg-0@example.com>', '<msg-1@example.com>'],
+    });
+    expect(result?.references).toEqual([
+      'msg-0@example.com',
+      'msg-1@example.com',
+    ]);
+  });
+
+  it('accepts bare Message-IDs without angle brackets', () => {
+    const result = computeReplyThreadingHeaders({
+      messageId: 'msg-2@example.com',
+      references: ['msg-1@example.com'],
+    });
+    expect(result).toEqual({
+      inReplyTo: ['msg-2@example.com'],
+      references: ['msg-1@example.com', 'msg-2@example.com'],
+    });
+  });
+
+  // JMAP RFC 8621 §4.1.2.3 returns messageId as String[]|null. Verify we
+  // don't crash on that shape even though most call sites pass a string.
+  it('accepts an array-shaped messageId per JMAP spec', () => {
+    const result = computeReplyThreadingHeaders({
+      messageId: ['<msg-2@example.com>'],
+      references: ['<msg-1@example.com>'],
+    });
+    expect(result).toEqual({
+      inReplyTo: ['msg-2@example.com'],
+      references: ['msg-1@example.com', 'msg-2@example.com'],
+    });
+  });
+
+  it('returns null for an empty messageId array', () => {
+    expect(computeReplyThreadingHeaders({ messageId: [] })).toBeNull();
+  });
+});

lib/__tests__/jmap-send-threading.test.ts

@@ -0,0 +1,151 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { JMAPClient } from '../jmap/client';
+
+function createClient(): JMAPClient {
+  const client = new JMAPClient('https://jmap.example.com', 'user@example.com', 'pass');
+  Object.assign(client, {
+    apiUrl: 'https://jmap.example.com/api',
+    accountId: 'account-1',
+    username: 'user@example.com',
+  });
+  return client;
+}
+
+interface JMAPMethodCall {
+  0: string;
+  1: Record<string, unknown>;
+  2: string;
+}
+
+interface CapturedRequest {
+  using?: string[];
+  methodCalls: JMAPMethodCall[];
+}
+
+/**
+ * Mock fetch to script three sequential JMAP requests sendEmail makes:
+ * Mailbox/get → Identity/get → Email/set + EmailSubmission/set.
+ * Returns the captured request bodies for assertions.
+ */
+function mockSendEmailFlow() {
+  const captured: CapturedRequest[] = [];
+  const fetchSpy = vi.spyOn(globalThis, 'fetch');
+
+  fetchSpy.mockImplementation(async (_url, init) => {
+    const body = JSON.parse((init as { body: string }).body) as CapturedRequest;
+    captured.push(body);
+    const callIdx = captured.length - 1;
+
+    let payload: unknown;
+    if (callIdx === 0) {
+      payload = {
+        methodResponses: [[
+          'Mailbox/get',
+          {
+            list: [
+              { id: 'mb-drafts', name: 'Drafts', role: 'drafts' },
+              { id: 'mb-sent', name: 'Sent', role: 'sent' },
+            ],
+          },
+          '0',
+        ]],
+      };
+    } else if (callIdx === 1) {
+      payload = {
+        methodResponses: [[
+          'Identity/get',
+          { list: [{ id: 'identity-1', email: 'user@example.com', mayDelete: false }] },
+          '0',
+        ]],
+      };
+    } else {
+      payload = {
+        methodResponses: [
+          ['Email/set', { created: { [Object.keys((captured[callIdx].methodCalls[0][1] as { create: Record<string, unknown> }).create)[0]]: { id: 'sent-id-1' } } }, '0'],
+          ['EmailSubmission/set', { created: { '1': { id: 'sub-1' } } }, '1'],
+        ],
+      };
+    }
+
+    return {
+      ok: true,
+      status: 200,
+      text: () => Promise.resolve(JSON.stringify(payload)),
+      json: () => Promise.resolve(payload),
+    } as Response;
+  });
+
+  return captured;
+}
+
+describe('JMAPClient.sendEmail threading headers', () => {
+  beforeEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('writes inReplyTo and references on the Email/set create when supplied', async () => {
+    const client = createClient();
+    const captured = mockSendEmailFlow();
+
+    await client.sendEmail(
+      ['recipient@example.com'],
+      'Re: testmail',
+      'reply body',
+      undefined, undefined, 'identity-1', 'user@example.com',
+      undefined, undefined, undefined, undefined,
+      ['<parent@example.com>'],
+      ['<root@example.com>', '<parent@example.com>'],
+    );
+
+    // Third request is the Email/set + EmailSubmission/set batch.
+    const setCall = captured[2].methodCalls[0];
+    expect(setCall[0]).toBe('Email/set');
+    const create = setCall[1].create as Record<string, Record<string, unknown>>;
+    const draft = Object.values(create)[0];
+
+    // Bare msg-ids per RFC 8621 — angle brackets stripped.
+    expect(draft.inReplyTo).toEqual(['parent@example.com']);
+    expect(draft.references).toEqual(['root@example.com', 'parent@example.com']);
+  });
+
+  it('omits threading fields when no parent ids are supplied', async () => {
+    const client = createClient();
+    const captured = mockSendEmailFlow();
+
+    await client.sendEmail(
+      ['recipient@example.com'],
+      'Fresh thread',
+      'body',
+      undefined, undefined, 'identity-1', 'user@example.com',
+    );
+
+    const setCall = captured[2].methodCalls[0];
+    const create = setCall[1].create as Record<string, Record<string, unknown>>;
+    const draft = Object.values(create)[0];
+
+    expect(draft.inReplyTo).toBeUndefined();
+    expect(draft.references).toBeUndefined();
+  });
+
+  it('drops empty / whitespace-only ids rather than sending blank entries', async () => {
+    const client = createClient();
+    const captured = mockSendEmailFlow();
+
+    await client.sendEmail(
+      ['recipient@example.com'],
+      'Re: testmail',
+      'body',
+      undefined, undefined, 'identity-1', 'user@example.com',
+      undefined, undefined, undefined, undefined,
+      ['<>', '   ', '<real@example.com>'],
+      [],
+    );
+
+    const setCall = captured[2].methodCalls[0];
+    const create = setCall[1].create as Record<string, Record<string, unknown>>;
+    const draft = Object.values(create)[0];
+
+    expect(draft.inReplyTo).toEqual(['real@example.com']);
+    expect(draft.references).toBeUndefined();
+  });
+});

lib/__tests__/plugin-store.test.ts

@@ -47,6 +47,8 @@ function resetStore() {
       'email-banner': [],
       'email-footer': [],
       'composer-toolbar': [],
+      'composer-sidebar': [],
+      'composer-sidebar-right': [],
       'sidebar-widget': [],
       'email-detail-sidebar': [],
       'settings-section': [],

lib/__tests__/plugin-validator.test.ts

@@ -28,23 +28,11 @@ describe('extractTheme', () => {
   });
 
   it('rejects oversized theme', async () => {
-    const zip = new JSZip();
-    zip.file('manifest.json', JSON.stringify({
-      id: 'big-theme',
-      name: 'Big',
-      version: '1.0.0',
-      author: 'Test',
-      type: 'theme',
-      variants: ['light'],
-    }));
-    // Make a large file > 1MB
-    zip.file('theme.css', 'x'.repeat(1024 * 1024 + 1));
-
-    // Manually create oversized File
-    const oversizedFile = new File([new ArrayBuffer(1024 * 1024 + 1)], 'big.zip');
+    // Theme size limit is 2 MB; create a file just past it.
+    const oversizedFile = new File([new ArrayBuffer(2 * 1024 * 1024 + 1)], 'big.zip');
     const result = await extractTheme(oversizedFile);
     expect(result.valid).toBe(false);
-    expect(result.errors).toContain('Theme ZIP exceeds 1 MB size limit');
+    expect(result.errors).toContain('Theme ZIP exceeds 2 MB size limit');
   });
 
   it('rejects non-ZIP file', async () => {
@@ -139,6 +127,129 @@ describe('extractTheme', () => {
     expect(result.valid).toBe(true);
     expect(result.manifest!.id).toBe('nested-theme');
   });
+
+  // ── Theme API v2 (advanced manifest) ──────────────────────────────
+
+  it('compiles a v2 manifest with tokens and no theme.css', async () => {
+    const zip = new JSZip();
+    zip.file('manifest.json', JSON.stringify({
+      id: 'tokens-only',
+      name: 'Tokens Only',
+      version: '1.0.0',
+      author: 'Test',
+      type: 'theme',
+      variants: ['light', 'dark'],
+      apiVersion: 2,
+      tokens: {
+        light: { primary: '#1373d9', background: '#ffffff' },
+        dark: { primary: '#58c9ff', background: '#1a202c' },
+      },
+    }));
+    const file = await createZipFile(zip);
+    const result = await extractTheme(file);
+    expect(result.valid).toBe(true);
+    expect(result.css).toContain('--color-primary: #1373d9');
+    expect(result.css).toContain('--color-primary: #58c9ff');
+  });
+
+  it('concatenates compiled tokens with author-supplied theme.css', async () => {
+    const zip = new JSZip();
+    zip.file('manifest.json', JSON.stringify({
+      id: 'tokens-plus-css',
+      name: 'Tokens + CSS',
+      version: '1.0.0',
+      author: 'Test',
+      type: 'theme',
+      variants: ['light'],
+      apiVersion: 2,
+      tokens: { light: { primary: '#000' } },
+    }));
+    zip.file('theme.css', '@font-face { font-family: "X"; src: local("X"); }');
+    const file = await createZipFile(zip);
+    const result = await extractTheme(file);
+    expect(result.valid).toBe(true);
+    expect(result.css).toContain('--color-primary: #000');
+    expect(result.css).toContain('@font-face');
+  });
+
+  it('extracts a skin.css when shipped with a v2 manifest', async () => {
+    const zip = new JSZip();
+    zip.file('manifest.json', JSON.stringify({
+      id: 'with-skin',
+      name: 'With Skin',
+      version: '1.0.0',
+      author: 'Test',
+      type: 'theme',
+      variants: ['light'],
+      apiVersion: 2,
+      tokens: { light: { primary: '#000' } },
+    }));
+    zip.file('skin.css', '[data-tour="email-list"] { font-size: 13px; }');
+    const file = await createZipFile(zip);
+    const result = await extractTheme(file);
+    expect(result.valid).toBe(true);
+    expect(result.skin).not.toBeNull();
+    expect(result.skin!).toContain('[data-tour="email-list"]');
+  });
+
+  it('strips dangerous patterns from skin.css', async () => {
+    const zip = new JSZip();
+    zip.file('manifest.json', JSON.stringify({
+      id: 'evil-skin',
+      name: 'Evil',
+      version: '1.0.0',
+      author: 'Test',
+      type: 'theme',
+      variants: ['light'],
+      apiVersion: 2,
+      tokens: { light: { primary: '#000' } },
+    }));
+    zip.file('skin.css', '@import url("https://x.com/p.css"); button { background: javascript:alert(1); }');
+    const file = await createZipFile(zip);
+    const result = await extractTheme(file);
+    expect(result.valid).toBe(true);
+    expect(result.skin).not.toBeNull();
+    expect(result.skin!).not.toContain('javascript:');
+    expect(result.skin!).not.toContain('@import');
+    expect(result.warnings.some((w) => w.toLowerCase().includes('skin'))).toBe(true);
+  });
+
+  it('ignores skin.css when manifest is not v2', async () => {
+    const zip = new JSZip();
+    zip.file('manifest.json', JSON.stringify({
+      id: 'v1-with-skin',
+      name: 'V1',
+      version: '1.0.0',
+      author: 'Test',
+      type: 'theme',
+      variants: ['light'],
+    }));
+    zip.file('theme.css', ':root { --color-primary: #000; }');
+    zip.file('skin.css', 'body { display: none; }');
+    const file = await createZipFile(zip);
+    const result = await extractTheme(file);
+    expect(result.valid).toBe(true);
+    expect(result.skin).toBeNull();
+    expect(result.warnings.some((w) => w.includes('skin.css ignored'))).toBe(true);
+  });
+
+  it('rejects a v2 manifest with invalid density', async () => {
+    const zip = new JSZip();
+    zip.file('manifest.json', JSON.stringify({
+      id: 'bad-density',
+      name: 'Bad',
+      version: '1.0.0',
+      author: 'Test',
+      type: 'theme',
+      variants: ['light'],
+      density: 'gigantic',
+      tokens: { light: { primary: '#000' } },
+    }));
+    const file = await createZipFile(zip);
+    const result = await extractTheme(file);
+    expect(result.valid).toBe(false);
+    expect(result.errors.some((e) => e.includes('density'))).toBe(true);
+  });
 });
 
 describe('extractPlugin', () => {

lib/__tests__/sub-addressing.test.ts

@@ -6,6 +6,10 @@ import {
   suggestTagsForDomain,
   isValidTag,
   getTagValidationError,
+  isSupportedSubAddressDelimiter,
+  isValidSubAddressDelimiter,
+  SUPPORTED_SUB_ADDRESS_DELIMITERS,
+  DEFAULT_SUB_ADDRESS_DELIMITER,
   MAX_TAG_LENGTH,
 } from '../sub-addressing';
 
@@ -354,3 +358,122 @@ describe('getTagValidationError', () => {
     expect(getTagValidationError('日本語')).toBe('INVALID_CHARS');
   });
 });
+
+describe('custom delimiter', () => {
+  describe('parseSubAddress with non-default delimiter', () => {
+    it('should parse with "-" delimiter', () => {
+      const result = parseSubAddress('user-shopping@example.com', '-');
+      expect(result.baseUser).toBe('user');
+      expect(result.tag).toBe('shopping');
+    });
+
+    it('should parse with "." delimiter', () => {
+      const result = parseSubAddress('user.shopping@example.com', '.');
+      expect(result.baseUser).toBe('user');
+      expect(result.tag).toBe('shopping');
+    });
+
+    it('should parse with "=" delimiter', () => {
+      const result = parseSubAddress('user=shopping@example.com', '=');
+      expect(result.baseUser).toBe('user');
+      expect(result.tag).toBe('shopping');
+    });
+
+    it('should ignore "+" when "-" is configured as the delimiter', () => {
+      const result = parseSubAddress('user+shopping@example.com', '-');
+      expect(result.baseUser).toBe('user+shopping');
+      expect(result.tag).toBeNull();
+    });
+
+    it('should split on first occurrence when delimiter appears multiple times', () => {
+      const result = parseSubAddress('alice-shop-orders@example.com', '-');
+      expect(result.baseUser).toBe('alice');
+      expect(result.tag).toBe('shop-orders');
+    });
+  });
+
+  describe('generateSubAddress with non-default delimiter', () => {
+    it('should generate using "-" delimiter', () => {
+      expect(generateSubAddress('user@example.com', 'shopping', '-')).toBe('user-shopping@example.com');
+    });
+
+    it('should generate using "." delimiter', () => {
+      expect(generateSubAddress('user@example.com', 'shopping', '.')).toBe('user.shopping@example.com');
+    });
+
+    it('should replace existing tag using the configured delimiter', () => {
+      expect(generateSubAddress('user-old@example.com', 'new', '-')).toBe('user-new@example.com');
+    });
+
+    it('should not strip a "+" sign in the local part when delimiter is "-"', () => {
+      // "+" is not the delimiter so it should remain part of the base user
+      expect(generateSubAddress('user+plus@example.com', 'tag', '-')).toBe('user+plus-tag@example.com');
+    });
+  });
+
+  describe('isSupportedSubAddressDelimiter', () => {
+    it('accepts every supported delimiter', () => {
+      for (const delim of SUPPORTED_SUB_ADDRESS_DELIMITERS) {
+        expect(isSupportedSubAddressDelimiter(delim)).toBe(true);
+      }
+    });
+
+    it('rejects unsupported characters', () => {
+      expect(isSupportedSubAddressDelimiter('_')).toBe(false);
+      expect(isSupportedSubAddressDelimiter('++')).toBe(false);
+      expect(isSupportedSubAddressDelimiter('')).toBe(false);
+    });
+
+    it('default delimiter is supported', () => {
+      expect(isSupportedSubAddressDelimiter(DEFAULT_SUB_ADDRESS_DELIMITER)).toBe(true);
+    });
+  });
+
+  describe('isValidSubAddressDelimiter', () => {
+    it('accepts every preset delimiter', () => {
+      for (const delim of SUPPORTED_SUB_ADDRESS_DELIMITERS) {
+        expect(isValidSubAddressDelimiter(delim)).toBe(true);
+      }
+    });
+
+    it('accepts atext special characters as custom delimiters', () => {
+      const customs = ['~', '!', '#', '$', '%', '&', "'", '*', '/', '?', '^', '_', '`', '{', '|', '}'];
+      for (const c of customs) {
+        expect(isValidSubAddressDelimiter(c)).toBe(true);
+      }
+    });
+
+    it('rejects alphanumeric characters', () => {
+      expect(isValidSubAddressDelimiter('a')).toBe(false);
+      expect(isValidSubAddressDelimiter('Z')).toBe(false);
+      expect(isValidSubAddressDelimiter('0')).toBe(false);
+    });
+
+    it('rejects "@", whitespace, and quotes', () => {
+      expect(isValidSubAddressDelimiter('@')).toBe(false);
+      expect(isValidSubAddressDelimiter(' ')).toBe(false);
+      expect(isValidSubAddressDelimiter('\t')).toBe(false);
+      expect(isValidSubAddressDelimiter('"')).toBe(false);
+    });
+
+    it('rejects multi-character strings', () => {
+      expect(isValidSubAddressDelimiter('++')).toBe(false);
+      expect(isValidSubAddressDelimiter('abc')).toBe(false);
+    });
+
+    it('rejects empty / non-string inputs', () => {
+      expect(isValidSubAddressDelimiter('')).toBe(false);
+      expect(isValidSubAddressDelimiter(null)).toBe(false);
+      expect(isValidSubAddressDelimiter(undefined)).toBe(false);
+      expect(isValidSubAddressDelimiter(1)).toBe(false);
+    });
+
+    it('round-trips through parse/generate with a custom "~" delimiter', () => {
+      const generated = generateSubAddress('user@example.com', 'shopping', '~');
+      expect(generated).toBe('user~shopping@example.com');
+      const parsed = parseSubAddress(generated, '~');
+      expect(parsed.baseUser).toBe('user');
+      expect(parsed.tag).toBe('shopping');
+    });
+  });
+});

lib/__tests__/theme-compiler.test.ts

@@ -0,0 +1,181 @@
+import { describe, it, expect } from 'vitest';
+import { compileAdvancedTheme, isAdvancedManifest } from '../theme-compiler';
+import type { ThemeManifest } from '../plugin-types';
+
+const baseManifest = (overrides: Partial<ThemeManifest> = {}): ThemeManifest => ({
+  id: 't',
+  name: 'T',
+  version: '1.0.0',
+  author: 'tester',
+  description: '',
+  type: 'theme',
+  variants: ['light', 'dark'],
+  ...overrides,
+});
+
+describe('isAdvancedManifest', () => {
+  it('returns false for plain v1 manifests', () => {
+    expect(isAdvancedManifest(baseManifest())).toBe(false);
+  });
+
+  it.each([
+    { apiVersion: 2 as const },
+    { tokens: { light: { primary: '#000' } } },
+    { extends: 'builtin-nord' },
+    { derive: true },
+    { density: 'compact' as const },
+    { radii: { md: '6px' } },
+    { typography: { fontSans: 'Inter' } },
+  ])('returns true when manifest has %p', (extra) => {
+    expect(isAdvancedManifest(baseManifest(extra))).toBe(true);
+  });
+});
+
+describe('compileAdvancedTheme', () => {
+  it('emits :root and .dark blocks from token sets', () => {
+    const { css, errors } = compileAdvancedTheme(
+      baseManifest({
+        tokens: {
+          light: { primary: '#1373d9', background: '#ffffff' },
+          dark: { primary: '#58c9ff', background: '#1a202c' },
+        },
+      }),
+    );
+    expect(errors).toHaveLength(0);
+    expect(css).toMatch(/:root\s*\{[\s\S]*--color-primary:\s*#1373d9/);
+    expect(css).toMatch(/\.dark\s*\{[\s\S]*--color-primary:\s*#58c9ff/);
+  });
+
+  it('omits .dark block for light-only themes', () => {
+    const { css } = compileAdvancedTheme(
+      baseManifest({
+        variants: ['light'],
+        tokens: { light: { primary: '#000' }, dark: { primary: '#fff' } },
+      }),
+    );
+    expect(css).toContain(':root');
+    expect(css).not.toContain('.dark');
+  });
+
+  it('emits common tokens into both :root and .dark', () => {
+    const { css } = compileAdvancedTheme(
+      baseManifest({
+        tokens: {
+          common: { ring: '#abc' },
+          light: { background: '#fff' },
+          dark: { background: '#000' },
+        },
+      }),
+    );
+    const rootMatch = css.match(/:root\s*\{([\s\S]*?)\}/)?.[1] ?? '';
+    const darkMatch = css.match(/\.dark\s*\{([\s\S]*?)\}/)?.[1] ?? '';
+    expect(rootMatch).toContain('--color-ring: #abc');
+    expect(darkMatch).toContain('--color-ring: #abc');
+  });
+
+  it('derives a contrasting *-foreground when derive: true', () => {
+    const { css } = compileAdvancedTheme(
+      baseManifest({
+        derive: true,
+        tokens: { light: { primary: '#000000' }, dark: { primary: '#ffffff' } },
+      }),
+    );
+    expect(css).toMatch(/:root\s*\{[\s\S]*--color-primary-foreground:\s*#ffffff/);
+    expect(css).toMatch(/\.dark\s*\{[\s\S]*--color-primary-foreground:\s*#0f172a/);
+  });
+
+  it('respects an author-provided *-foreground over derive', () => {
+    const { css } = compileAdvancedTheme(
+      baseManifest({
+        derive: true,
+        tokens: {
+          light: { primary: '#000000', 'primary-foreground': '#ff00ff' },
+        },
+      }),
+    );
+    expect(css).toContain('--color-primary-foreground: #ff00ff');
+  });
+
+  it('emits radii, typography, and density vars', () => {
+    const { css } = compileAdvancedTheme(
+      baseManifest({
+        tokens: { light: { primary: '#000' } },
+        radii: { sm: '2px', md: '6px', full: '9999px' },
+        typography: { fontSans: 'Inter, sans-serif', baseFontSize: '15px' },
+        density: 'compact',
+      }),
+    );
+    expect(css).toContain('--radius-sm: 2px');
+    expect(css).toContain('--radius-full: 9999px');
+    expect(css).toContain('--font-sans: Inter, sans-serif');
+    expect(css).toContain('--font-size-base: 15px');
+    expect(css).toContain('--density-row-height: 28px');
+  });
+
+  it('drops tokens with unsafe values and warns', () => {
+    const { css, warnings } = compileAdvancedTheme(
+      baseManifest({
+        tokens: {
+          light: {
+            primary: '#000',
+            evil: 'red; background: url("https://x.com/track.png")',
+          },
+        },
+      }),
+    );
+    expect(css).toContain('--color-primary: #000');
+    expect(css).not.toContain('https://x.com');
+    expect(warnings.some((w) => w.includes('evil'))).toBe(true);
+  });
+
+  it('drops tokens with unsafe keys and warns', () => {
+    const { css, warnings } = compileAdvancedTheme(
+      baseManifest({
+        tokens: { light: { 'primary }; body { background: red': '#fff', primary: '#000' } },
+      }),
+    );
+    expect(css).toContain('--color-primary: #000');
+    expect(css).not.toContain('body { background');
+    expect(warnings.some((w) => w.includes('invalid key'))).toBe(true);
+  });
+
+  it('errors when no structured fields are present', () => {
+    const { errors } = compileAdvancedTheme(baseManifest());
+    expect(errors.length).toBeGreaterThan(0);
+  });
+
+  it('inlines parent CSS when extends + resolver supplied', () => {
+    const { css, warnings } = compileAdvancedTheme(
+      baseManifest({
+        extends: 'parent-theme',
+        tokens: { light: { primary: '#fff' } },
+      }),
+      { resolveExtends: (id) => (id === 'parent-theme' ? ':root { --x: 1; }' : null) },
+    );
+    expect(css).toContain('--x: 1');
+    expect(css).toContain('--color-primary: #fff');
+    expect(warnings).toHaveLength(0);
+  });
+
+  it('warns when extends parent cannot be resolved', () => {
+    const { warnings } = compileAdvancedTheme(
+      baseManifest({
+        extends: 'missing',
+        tokens: { light: { primary: '#fff' } },
+      }),
+      { resolveExtends: () => null },
+    );
+    expect(warnings.some((w) => w.includes('missing'))).toBe(true);
+  });
+
+  it('appends user-supplied CSS after compiled output', () => {
+    const { css } = compileAdvancedTheme(
+      baseManifest({ tokens: { light: { primary: '#fff' } } }),
+      { userCSS: '@font-face { font-family: "X"; src: local("X"); }' },
+    );
+    const compiledIdx = css.indexOf('--color-primary');
+    const userIdx = css.indexOf('@font-face');
+    expect(compiledIdx).toBeGreaterThanOrEqual(0);
+    expect(userIdx).toBeGreaterThan(compiledIdx);
+  });
+});

lib/__tests__/theme-loader.test.ts

@@ -1,9 +1,12 @@
 import { describe, it, expect, afterEach } from 'vitest';
 import {
   sanitizeThemeCSS,
+  sanitizeSkinCSS,
   validateThemeSelectors,
   injectThemeCSS,
   removeThemeCSS,
+  injectThemeSkinCSS,
+  removeThemeSkinCSS,
   validateThemeCSSSafety,
 } from '../theme-loader';
 
@@ -144,6 +147,64 @@ describe('theme-loader', () => {
     });
   });
 
+  describe('injectThemeSkinCSS / removeThemeSkinCSS', () => {
+    afterEach(() => {
+      removeThemeSkinCSS();
+    });
+
+    it('injects a separate <style> tag from the colour block', () => {
+      injectThemeCSS(':root { --color-primary: red; }');
+      injectThemeSkinCSS('button { padding: 4px; }', 'thunderbird');
+      expect(document.getElementById('active-theme')).not.toBeNull();
+      expect(document.getElementById('active-theme-skin')).not.toBeNull();
+      expect(document.getElementById('active-theme-skin')?.textContent).toContain('button');
+    });
+
+    it('sets data-theme-skin on body to the active theme id', () => {
+      injectThemeSkinCSS('button { padding: 4px; }', 'my-theme');
+      expect(document.body.getAttribute('data-theme-skin')).toBe('my-theme');
+    });
+
+    it('removes the skin tag and body attribute on remove', () => {
+      injectThemeSkinCSS('button { padding: 4px; }', 'my-theme');
+      removeThemeSkinCSS();
+      expect(document.getElementById('active-theme-skin')).toBeNull();
+      expect(document.body.getAttribute('data-theme-skin')).toBeNull();
+    });
+
+    it('does not throw when removing without a prior inject', () => {
+      expect(() => removeThemeSkinCSS()).not.toThrow();
+    });
+  });
+
+  describe('sanitizeSkinCSS', () => {
+    it('preserves component-level selectors', () => {
+      const css = '[data-tour="email-list"] { font-size: 13px; } button { padding: 4px; }';
+      const { css: cleaned, warnings } = sanitizeSkinCSS(css);
+      expect(cleaned).toBe(css);
+      expect(warnings).toHaveLength(0);
+    });
+
+    it('strips dangerous patterns', () => {
+      const { css: cleaned, warnings } = sanitizeSkinCSS(
+        '@import url("https://x.com/p.css"); button { background: javascript:alert(1); }',
+      );
+      expect(cleaned).not.toContain('@import');
+      expect(cleaned).not.toContain('javascript:');
+      expect(warnings.length).toBeGreaterThanOrEqual(2);
+    });
+
+    it('strips @charset and @namespace', () => {
+      const { css: cleaned, warnings } = sanitizeSkinCSS(
+        '@charset "utf-8"; @namespace url(http://www.w3.org/1999/xhtml); button { padding: 4px; }',
+      );
+      expect(cleaned).not.toContain('@charset');
+      expect(cleaned).not.toContain('@namespace');
+      expect(cleaned).toContain('button');
+      expect(warnings.length).toBeGreaterThanOrEqual(2);
+    });
+  });
+
   describe('validateThemeCSSSafety', () => {
     it('accepts valid theme CSS', () => {
       const css = ':root { --color-primary: #3b82f6; --color-background: #fff; }';

lib/__tests__/url-guard.test.ts

@@ -0,0 +1,124 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+
+const lookup = vi.fn();
+
+vi.mock('node:dns/promises', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('node:dns/promises')>();
+  return {
+    ...actual,
+    default: { ...actual, lookup: (...args: unknown[]) => lookup(...args) },
+    lookup: (...args: unknown[]) => lookup(...args),
+  };
+});
+
+describe('isPublicHttpUrl', () => {
+  beforeEach(() => {
+    lookup.mockReset();
+  });
+
+  afterEach(() => {
+    vi.resetModules();
+  });
+
+  async function load() {
+    const mod = await import('@/lib/security/url-guard');
+    return mod.isPublicHttpUrl;
+  }
+
+  it('accepts public https URLs whose DNS resolves to a public address', async () => {
+    lookup.mockResolvedValue([{ address: '93.184.216.34', family: 4 }]);
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('https://example.com/jmap')).toBe(true);
+  });
+
+  it('rejects malformed URLs', async () => {
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('not a url')).toBe(false);
+    expect(await isPublicHttpUrl('')).toBe(false);
+  });
+
+  it('rejects non-http(s) protocols', async () => {
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('file:///etc/passwd')).toBe(false);
+    expect(await isPublicHttpUrl('gopher://example.com/')).toBe(false);
+    expect(await isPublicHttpUrl('javascript:alert(1)')).toBe(false);
+  });
+
+  it('rejects URLs with embedded credentials', async () => {
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('https://user:pass@example.com/')).toBe(false);
+    expect(await isPublicHttpUrl('https://user@example.com/')).toBe(false);
+  });
+
+  it('rejects loopback hostnames without DNS', async () => {
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('http://localhost/')).toBe(false);
+    expect(await isPublicHttpUrl('http://service.localhost/')).toBe(false);
+    expect(await isPublicHttpUrl('http://server.local/')).toBe(false);
+    expect(await isPublicHttpUrl('http://kube.internal/api')).toBe(false);
+    expect(await isPublicHttpUrl('http://1.0.0.127.in-addr.arpa/')).toBe(false);
+    expect(lookup).not.toHaveBeenCalled();
+  });
+
+  it('rejects literal IPv4 loopback and RFC-1918 ranges', async () => {
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('http://127.0.0.1/')).toBe(false);
+    expect(await isPublicHttpUrl('http://10.0.0.5/')).toBe(false);
+    expect(await isPublicHttpUrl('http://10.255.255.255/')).toBe(false);
+    expect(await isPublicHttpUrl('http://172.16.0.1/')).toBe(false);
+    expect(await isPublicHttpUrl('http://172.31.255.254/')).toBe(false);
+    expect(await isPublicHttpUrl('http://192.168.1.1/')).toBe(false);
+    expect(await isPublicHttpUrl('http://0.0.0.0/')).toBe(false);
+    expect(lookup).not.toHaveBeenCalled();
+  });
+
+  it('rejects literal AWS / GCP / Azure metadata IP', async () => {
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('http://169.254.169.254/latest/meta-data/')).toBe(false);
+    expect(await isPublicHttpUrl('http://169.254.0.1/')).toBe(false);
+    expect(lookup).not.toHaveBeenCalled();
+  });
+
+  it('rejects IPv6 loopback, ULA, and link-local literals', async () => {
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('http://[::1]/')).toBe(false);
+    expect(await isPublicHttpUrl('http://[::]/')).toBe(false);
+    expect(await isPublicHttpUrl('http://[fc00::1]/')).toBe(false);
+    expect(await isPublicHttpUrl('http://[fd12:3456::1]/')).toBe(false);
+    expect(await isPublicHttpUrl('http://[fe80::1]/')).toBe(false);
+    expect(lookup).not.toHaveBeenCalled();
+  });
+
+  it('rejects when DNS resolves to a private address (rebinding)', async () => {
+    lookup.mockResolvedValue([{ address: '127.0.0.1', family: 4 }]);
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('https://evil.example.com/')).toBe(false);
+  });
+
+  it('rejects when any resolved address is private (mixed)', async () => {
+    lookup.mockResolvedValue([
+      { address: '93.184.216.34', family: 4 },
+      { address: '10.0.0.1', family: 4 },
+    ]);
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('https://mixed.example.com/')).toBe(false);
+  });
+
+  it('rejects when DNS resolves to IPv6 loopback', async () => {
+    lookup.mockResolvedValue([{ address: '::1', family: 6 }]);
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('https://evil6.example.com/')).toBe(false);
+  });
+
+  it('rejects when DNS lookup throws', async () => {
+    lookup.mockRejectedValue(new Error('ENOTFOUND'));
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('https://nonexistent.example.com/')).toBe(false);
+  });
+
+  it('rejects when DNS returns no records', async () => {
+    lookup.mockResolvedValue([]);
+    const isPublicHttpUrl = await load();
+    expect(await isPublicHttpUrl('https://empty.example.com/')).toBe(false);
+  });
+});

lib/__tests__/vcard.test.ts

@@ -34,11 +34,11 @@ describe("parseVCard", () => {
     expect(result).toHaveLength(1);
     const components = result[0].name?.components || [];
     expect(components).toEqual([
-      { kind: "prefix", value: "Mr." },
+      { kind: "title", value: "Mr." },
       { kind: "given", value: "John" },
-      { kind: "additional", value: "Michael" },
+      { kind: "given2", value: "Michael" },
       { kind: "surname", value: "Doe" },
-      { kind: "suffix", value: "Jr." },
+      { kind: "generation", value: "Jr." },
     ]);
   });
 
@@ -52,6 +52,21 @@ describe("parseVCard", () => {
     expect(components.find((c) => c.kind === "surname")?.value).toBe("Doe");
   });
 
+  it("maps prefix and middle name to RFC 9553 standard kinds (issue #224)", () => {
+    // N: family;given;additional;prefix;suffix (RFC 6350 order)
+    const withPrefix = parseVCard(`BEGIN:VCARD\r\nVERSION:3.0\r\nN:Smith;John;;Mr.;\r\nEMAIL:j@example.com\r\nEND:VCARD`);
+    const c1 = withPrefix[0].name?.components || [];
+    expect(c1.find((c) => c.kind === "surname")?.value).toBe("Smith");
+    expect(c1.find((c) => c.kind === "given")?.value).toBe("John");
+    expect(c1.find((c) => c.kind === "title")?.value).toBe("Mr.");
+
+    const withMiddle = parseVCard(`BEGIN:VCARD\r\nVERSION:3.0\r\nN:Smith;John;Mike;;\r\nEMAIL:j@example.com\r\nEND:VCARD`);
+    const c2 = withMiddle[0].name?.components || [];
+    expect(c2.find((c) => c.kind === "surname")?.value).toBe("Smith");
+    expect(c2.find((c) => c.kind === "given")?.value).toBe("John");
+    expect(c2.find((c) => c.kind === "given2")?.value).toBe("Mike");
+  });
+
   it("parses vCard with phone, org, and address", () => {
     const vcf = [
       "BEGIN:VCARD",
@@ -204,6 +219,60 @@ describe("parseVCard", () => {
     expect(result[0].kind).toBe("group");
   });
 
+  it("decodes ENCODING=QUOTED-PRINTABLE values with UTF-8 charset", () => {
+    const vcf = [
+      "BEGIN:VCARD",
+      "VERSION:2.1",
+      "N;CHARSET=UTF-8;ENCODING=QUOTED-PRINTABLE:M=C3=BCller;Hans;;;",
+      "FN;CHARSET=UTF-8;ENCODING=QUOTED-PRINTABLE:Hans M=C3=BCller",
+      "NOTE;CHARSET=UTF-8;ENCODING=QUOTED-PRINTABLE:Caf=C3=A9 stra=C3=9Fe",
+      "EMAIL:hans@example.com",
+      "END:VCARD",
+    ].join("\r\n");
+
+    const result = parseVCard(vcf);
+    expect(result).toHaveLength(1);
+    const card = result[0];
+
+    const components = card.name?.components || [];
+    expect(components.find((c) => c.kind === "given")?.value).toBe("Hans");
+    expect(components.find((c) => c.kind === "surname")?.value).toBe("Müller");
+    expect(card.notes?.n0?.note).toBe("Café straße");
+  });
+
+  it("joins QUOTED-PRINTABLE soft line breaks (= at end of line)", () => {
+    const vcf = [
+      "BEGIN:VCARD",
+      "VERSION:2.1",
+      "FN;CHARSET=UTF-8;ENCODING=QUOTED-PRINTABLE:Hans=20J=",
+      "=C3=BCrgen=20M=C3=BCller",
+      "EMAIL:hj@example.com",
+      "END:VCARD",
+    ].join("\r\n");
+
+    const result = parseVCard(vcf);
+    expect(result).toHaveLength(1);
+    const components = result[0].name?.components || [];
+    const given = components.find((c) => c.kind === "given")?.value;
+    const surname = components.find((c) => c.kind === "surname")?.value;
+    expect(given).toBe("Hans");
+    expect(surname).toBe("Jürgen Müller");
+  });
+
+  it("recognizes bare QUOTED-PRINTABLE encoding parameter (vCard 2.1 style)", () => {
+    const vcf = [
+      "BEGIN:VCARD",
+      "VERSION:2.1",
+      "FN;QUOTED-PRINTABLE;CHARSET=UTF-8:Caf=C3=A9",
+      "EMAIL:c@example.com",
+      "END:VCARD",
+    ].join("\r\n");
+
+    const result = parseVCard(vcf);
+    const components = result[0].name?.components || [];
+    expect(components.find((c) => c.kind === "given")?.value).toBe("Café");
+  });
+
   it("parses GENDER, LOGO, SOUND, LABEL, CALURI, CALADRURI, FBURL, SOURCE", () => {
     const vcf = [
       "BEGIN:VCARD",

lib/__tests__/verify-jmap-auth.test.ts

@@ -0,0 +1,175 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+
+const lookup = vi.fn();
+
+vi.mock('node:dns/promises', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('node:dns/promises')>();
+  return {
+    ...actual,
+    default: { ...actual, lookup: (...args: unknown[]) => lookup(...args) },
+    lookup: (...args: unknown[]) => lookup(...args),
+  };
+});
+
+describe('verifyJmapAuth SSRF protection', () => {
+  let fetchSpy: ReturnType<typeof vi.spyOn>;
+
+  beforeEach(() => {
+    lookup.mockReset();
+    vi.resetModules();
+    fetchSpy = vi.spyOn(globalThis, 'fetch');
+  });
+
+  afterEach(() => {
+    fetchSpy.mockRestore();
+  });
+
+  async function load() {
+    const mod = await import('@/lib/auth/verify-jmap-auth');
+    return mod;
+  }
+
+  it('rejects loopback literal without issuing fetch', async () => {
+    const { verifyJmapAuth, JmapAuthVerificationError } = await load();
+    await expect(verifyJmapAuth('http://127.0.0.1', 'Bearer x')).rejects.toBeInstanceOf(
+      JmapAuthVerificationError,
+    );
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+
+  it('rejects AWS IMDS endpoint without issuing fetch', async () => {
+    const { verifyJmapAuth } = await load();
+    await expect(
+      verifyJmapAuth('http://169.254.169.254', 'Bearer x'),
+    ).rejects.toMatchObject({ status: 400 });
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+
+  it('rejects RFC-1918 literals without issuing fetch', async () => {
+    const { verifyJmapAuth } = await load();
+    for (const target of ['http://10.0.0.5', 'http://172.16.0.1', 'http://192.168.1.1']) {
+      await expect(verifyJmapAuth(target, 'Bearer x')).rejects.toMatchObject({ status: 400 });
+    }
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+
+  it('rejects localhost hostname without issuing fetch', async () => {
+    const { verifyJmapAuth } = await load();
+    await expect(verifyJmapAuth('http://localhost', 'Bearer x')).rejects.toMatchObject({
+      status: 400,
+    });
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+
+  it('rejects IPv6 loopback literal without issuing fetch', async () => {
+    const { verifyJmapAuth } = await load();
+    await expect(verifyJmapAuth('http://[::1]', 'Bearer x')).rejects.toMatchObject({
+      status: 400,
+    });
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+
+  it('rejects hostnames whose DNS resolves to a private IP without issuing fetch', async () => {
+    lookup.mockResolvedValue([{ address: '10.0.0.1', family: 4 }]);
+    const { verifyJmapAuth } = await load();
+    await expect(verifyJmapAuth('https://internal.example.com', 'Bearer x')).rejects.toMatchObject({
+      status: 400,
+    });
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+
+  it('rejects file:// URLs', async () => {
+    const { verifyJmapAuth } = await load();
+    await expect(verifyJmapAuth('file:///etc/passwd', 'Bearer x')).rejects.toMatchObject({
+      status: 400,
+    });
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+
+  it('refuses to follow a redirect to a private address', async () => {
+    lookup.mockResolvedValue([{ address: '93.184.216.34', family: 4 }]);
+    fetchSpy.mockResolvedValueOnce(
+      new Response(null, { status: 302, headers: { location: 'http://127.0.0.1/.well-known/jmap' } }),
+    );
+    const { verifyJmapAuth } = await load();
+    await expect(verifyJmapAuth('https://example.com', 'Bearer x')).rejects.toMatchObject({
+      status: 400,
+    });
+    expect(fetchSpy).toHaveBeenCalledTimes(1);
+  });
+
+  it('refuses to follow a redirect to AWS IMDS', async () => {
+    lookup.mockResolvedValue([{ address: '93.184.216.34', family: 4 }]);
+    fetchSpy.mockResolvedValueOnce(
+      new Response(null, {
+        status: 302,
+        headers: { location: 'http://169.254.169.254/latest/meta-data/' },
+      }),
+    );
+    const { verifyJmapAuth } = await load();
+    await expect(verifyJmapAuth('https://example.com', 'Bearer x')).rejects.toMatchObject({
+      status: 400,
+    });
+    expect(fetchSpy).toHaveBeenCalledTimes(1);
+  });
+
+  it('accepts a public host that returns a valid JMAP session', async () => {
+    lookup.mockResolvedValue([{ address: '93.184.216.34', family: 4 }]);
+    fetchSpy.mockResolvedValueOnce(
+      new Response(JSON.stringify({ apiUrl: 'https://example.com/api', accounts: {} }), {
+        status: 200,
+        headers: { 'content-type': 'application/json' },
+      }),
+    );
+    const { verifyJmapAuth } = await load();
+    await expect(verifyJmapAuth('https://example.com', 'Bearer x')).resolves.toBe(
+      'https://example.com',
+    );
+    expect(fetchSpy).toHaveBeenCalledWith(
+      'https://example.com/.well-known/jmap',
+      expect.objectContaining({ redirect: 'manual' }),
+    );
+  });
+
+  it('rejects an invalid Authorization header before any fetch', async () => {
+    const { verifyJmapAuth } = await load();
+    await expect(verifyJmapAuth('https://example.com', 'NotAuth')).rejects.toMatchObject({
+      status: 400,
+    });
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+
+  it('with trusted=true, accepts a hostname resolving to a private IP', async () => {
+    lookup.mockResolvedValue([{ address: '10.0.20.5', family: 4 }]);
+    fetchSpy.mockResolvedValueOnce(
+      new Response(JSON.stringify({ apiUrl: 'https://mail.internal/api', accounts: {} }), {
+        status: 200,
+        headers: { 'content-type': 'application/json' },
+      }),
+    );
+    const { verifyJmapAuth } = await load();
+    await expect(
+      verifyJmapAuth('https://mail.internal', 'Bearer x', { trusted: true }),
+    ).resolves.toBe('https://mail.internal');
+    expect(fetchSpy).toHaveBeenCalledWith(
+      'https://mail.internal/.well-known/jmap',
+      expect.objectContaining({ redirect: 'manual' }),
+    );
+  });
+
+  it('with trusted=true, still rejects unsupported protocols', async () => {
+    const { verifyJmapAuth } = await load();
+    await expect(
+      verifyJmapAuth('file:///etc/passwd', 'Bearer x', { trusted: true }),
+    ).rejects.toMatchObject({ status: 400 });
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+
+  it('with trusted=true, still rejects an invalid Authorization header', async () => {
+    const { verifyJmapAuth } = await load();
+    await expect(
+      verifyJmapAuth('https://mail.internal', 'NotAuth', { trusted: true }),
+    ).rejects.toMatchObject({ status: 400 });
+    expect(fetchSpy).not.toHaveBeenCalled();
+  });
+});

lib/admin/config-manager.ts

@@ -2,7 +2,8 @@ import { readFile, writeFile, mkdir, rename } from 'node:fs/promises';
 import { existsSync } from 'node:fs';
 import path from 'node:path';
 import { logger } from '@/lib/logger';
-import { CONFIG_ENV_MAP, DEFAULT_POLICY, DEFAULT_THEME_POLICY, type SettingsPolicy } from './types';
+import { readFileEnv } from '@/lib/read-file-env';
+import { CONFIG_ENV_MAP, DEFAULT_FEATURE_GATES, DEFAULT_POLICY, DEFAULT_THEME_POLICY, type SettingsPolicy } from './types';
 
 function getAdminDir(): string {
   return process.env.ADMIN_DATA_DIR || path.join(process.cwd(), 'data', 'admin');
@@ -34,6 +35,7 @@ class ConfigManager {
       this.policyCache = {
         ...DEFAULT_POLICY,
         ...policy,
+        features: { ...DEFAULT_FEATURE_GATES, ...(policy.features || {}) },
         themePolicy: { ...DEFAULT_THEME_POLICY, ...(policy.themePolicy || {}) },
       };
     } else {
@@ -64,6 +66,12 @@ class ConfigManager {
       if (envVal !== undefined) {
         return parseEnvValue(envVal, mapping.type) as T;
       }
+      if (mapping.fileEnvVar) {
+        const fileVal = readFileEnv(process.env[mapping.fileEnvVar]);
+        if (fileVal !== null) {
+          return parseEnvValue(fileVal, mapping.type) as T;
+        }
+      }
       if (defaultValue !== undefined) return defaultValue;
       return mapping.defaultValue as T;
     }
@@ -94,9 +102,16 @@ class ConfigManager {
         const envVal = process.env[mapping.envVar];
         if (envVal !== undefined) {
           result[key] = { value: parseEnvValue(envVal, mapping.type), source: 'env' };
-        } else {
-          result[key] = { value: mapping.defaultValue, source: 'default' };
+          continue;
         }
+        if (mapping.fileEnvVar) {
+          const fileVal = readFileEnv(process.env[mapping.fileEnvVar]);
+          if (fileVal !== null) {
+            result[key] = { value: parseEnvValue(fileVal, mapping.type), source: 'env' };
+            continue;
+          }
+        }
+        result[key] = { value: mapping.defaultValue, source: 'default' };
       }
     }
     return result;
@@ -129,7 +144,12 @@ class ConfigManager {
    * Update the settings policy. Writes to disk.
    */
   async setPolicy(policy: SettingsPolicy): Promise<void> {
-    this.policyCache = { ...DEFAULT_POLICY, ...policy };
+    this.policyCache = {
+      ...DEFAULT_POLICY,
+      ...policy,
+      features: { ...DEFAULT_FEATURE_GATES, ...(policy.features || {}) },
+      themePolicy: { ...DEFAULT_THEME_POLICY, ...(policy.themePolicy || {}) },
+    };
     await this.writeJsonFile('policy.json', this.policyCache as unknown as Record<string, unknown>);
   }
 

lib/admin/csp-frame-origins.ts

@@ -0,0 +1,102 @@
+/**
+ * Computes the union of CSP `frame-src` origins declared by installed and
+ * enabled plugins. The proxy reads this on each request so that plugins can
+ * embed external content (YouTube, Vimeo, Jitsi, …) without us hard-coding
+ * domains in the host CSP.
+ *
+ * Origins are validated at install time and re-validated here as defense in
+ * depth - any malformed value is dropped so a corrupted registry can never
+ * inject arbitrary CSP fragments.
+ */
+
+import { getPluginRegistry } from './plugin-registry';
+
+// `https://host`, `https://host:port`, or `https://*.host[:port]`
+//
+// Each label is alphanumeric with optional inner dashes; the final TLD label
+// MUST start with a letter so we reject raw IPv4 literals.
+//
+// Disallowed by the regex (intentionally):
+//   - any scheme other than https
+//   - paths, queries, fragments
+//   - userinfo, IPv4 literals, IPv6 literals (`[::1]`)
+//   - bare wildcards (`https://*`)
+const FRAME_ORIGIN_RE =
+  /^https:\/\/(?:\*\.)?(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?)(?:\.(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?))*\.(?:[a-z](?:[a-z0-9-]*[a-z0-9])?)(?::[0-9]{1,5})?$/i;
+
+export function isValidFrameOrigin(origin: unknown): origin is string {
+  if (typeof origin !== 'string') return false;
+  if (origin.length > 200) return false;
+  if (!FRAME_ORIGIN_RE.test(origin)) return false;
+  // Reject control characters / whitespace as a final safeguard against
+  // anything that would let an attacker break out of the directive.
+  if (/[\s'"`;,()]/.test(origin)) return false;
+  return true;
+}
+
+/**
+ * Sanitises a list of candidate origins from a manifest. Drops invalid
+ * entries silently and dedupes (case-insensitive on the host).
+ */
+export function sanitizeFrameOrigins(input: unknown): string[] {
+  if (!Array.isArray(input)) return [];
+  const seen = new Set<string>();
+  const out: string[] = [];
+  for (const value of input) {
+    if (!isValidFrameOrigin(value)) continue;
+    const key = value.toLowerCase();
+    if (seen.has(key)) continue;
+    seen.add(key);
+    out.push(value);
+  }
+  return out;
+}
+
+// In-memory cache. The proxy fires on every page navigation; reading the
+// registry JSON every time is fine but cheap to skip when nothing has
+// changed. Five seconds is short enough to make plugin install/uninstall
+// feel snappy without measurable overhead.
+let cachedAt = 0;
+let cachedOrigins: string[] = [];
+const CACHE_TTL_MS = 5_000;
+
+/**
+ * Returns the union of frame origins declared by every enabled plugin in
+ * the server-side registry, deduped and validated.
+ *
+ * Returns an empty array on any failure (missing file, parse error, …) so
+ * a broken registry only ever shrinks the CSP - never widens it.
+ */
+export async function getEnabledPluginFrameOrigins(): Promise<string[]> {
+  const now = Date.now();
+  if (now - cachedAt < CACHE_TTL_MS) return cachedOrigins;
+
+  try {
+    const registry = await getPluginRegistry();
+    const seen = new Set<string>();
+    const out: string[] = [];
+    for (const plugin of registry.plugins) {
+      if (!plugin.enabled) continue;
+      const origins = sanitizeFrameOrigins(plugin.frameOrigins);
+      for (const o of origins) {
+        const key = o.toLowerCase();
+        if (seen.has(key)) continue;
+        seen.add(key);
+        out.push(o);
+      }
+    }
+    cachedOrigins = out;
+    cachedAt = now;
+    return out;
+  } catch {
+    cachedOrigins = [];
+    cachedAt = now;
+    return [];
+  }
+}
+
+/** Force the next call to re-read the registry. Used by install/uninstall. */
+export function invalidateFrameOriginsCache(): void {
+  cachedAt = 0;
+  cachedOrigins = [];
+}

lib/admin/plugin-registry.ts

@@ -41,6 +41,11 @@ export interface ServerPlugin {
   configSchema?: Record<string, PluginConfigField>;
   installedAt: string;
   updatedAt: string;
+  /**
+   * Validated CSP origins (https-only, single-origin form) the plugin may
+   * embed. Merged into the host frame-src by the proxy.
+   */
+  frameOrigins?: string[];
 }
 
 export interface ServerTheme {

lib/admin/types.ts

@@ -39,6 +39,7 @@ export interface FeatureGates {
   folderIconsEnabled: boolean;
   hoverActionsConfigEnabled: boolean;
   filesEnabled: boolean;
+  contactsEnabled: boolean;
 }
 
 export const DEFAULT_FEATURE_GATES: FeatureGates = {
@@ -58,6 +59,7 @@ export const DEFAULT_FEATURE_GATES: FeatureGates = {
   folderIconsEnabled: true,
   hoverActionsConfigEnabled: true,
   filesEnabled: true,
+  contactsEnabled: true,
 };
 
 export interface ThemePolicy {
@@ -106,7 +108,7 @@ export interface AuditEntry {
 }
 
 /** Config keys that map to environment variables */
-export const CONFIG_ENV_MAP: Record<string, { envVar: string; type: 'string' | 'boolean' | 'url' | 'enum'; defaultValue: unknown; enumValues?: string[] }> = {
+export const CONFIG_ENV_MAP: Record<string, { envVar: string; fileEnvVar?: string; type: 'string' | 'boolean' | 'url' | 'enum'; defaultValue: unknown; enumValues?: string[] }> = {
   appName: { envVar: 'APP_NAME', type: 'string', defaultValue: 'Webmail' },
   jmapServerUrl: { envVar: 'JMAP_SERVER_URL', type: 'url', defaultValue: '' },
   stalwartFeaturesEnabled: { envVar: 'STALWART_FEATURES', type: 'boolean', defaultValue: true },
@@ -124,7 +126,7 @@ export const CONFIG_ENV_MAP: Record<string, { envVar: string; type: 'string' | '
   oauthEnabled: { envVar: 'OAUTH_ENABLED', type: 'boolean', defaultValue: false },
   oauthOnly: { envVar: 'OAUTH_ONLY', type: 'boolean', defaultValue: false },
   oauthClientId: { envVar: 'OAUTH_CLIENT_ID', type: 'string', defaultValue: '' },
-  oauthClientSecret: { envVar: 'OAUTH_CLIENT_SECRET', type: 'string', defaultValue: '' },
+  oauthClientSecret: { envVar: 'OAUTH_CLIENT_SECRET', fileEnvVar: 'OAUTH_CLIENT_SECRET_FILE', type: 'string', defaultValue: '' },
   oauthIssuerUrl: { envVar: 'OAUTH_ISSUER_URL', type: 'url', defaultValue: '' },
   allowCustomJmapEndpoint: { envVar: 'ALLOW_CUSTOM_JMAP_ENDPOINT', type: 'boolean', defaultValue: false },
   autoSsoEnabled: { envVar: 'AUTO_SSO_ENABLED', type: 'boolean', defaultValue: false },
@@ -134,7 +136,7 @@ export const CONFIG_ENV_MAP: Record<string, { envVar: string; type: 'string' | '
   settingsSyncEnabled: { envVar: 'SETTINGS_SYNC_ENABLED', type: 'boolean', defaultValue: false },
   logFormat: { envVar: 'LOG_FORMAT', type: 'enum', defaultValue: 'text', enumValues: ['text', 'json'] },
   logLevel: { envVar: 'LOG_LEVEL', type: 'enum', defaultValue: 'info', enumValues: ['error', 'warn', 'info', 'debug'] },
-  sessionSecret: { envVar: 'SESSION_SECRET', type: 'string', defaultValue: '' },
+  sessionSecret: { envVar: 'SESSION_SECRET', fileEnvVar: 'SESSION_SECRET_FILE', type: 'string', defaultValue: '' },
 };
 
 /** Keys that should never be exposed to the client config endpoint */

lib/auth/verify-jmap-auth.ts

@@ -1,4 +1,7 @@
+import { isPublicHttpUrl } from '@/lib/security/url-guard';
+
 const VERIFY_TIMEOUT_MS = 10000;
+const MAX_REDIRECTS = 3;
 
 export class JmapAuthVerificationError extends Error {
   status: number;
@@ -37,19 +40,55 @@ export function validateProxyAuthHeader(authHeader: string): void {
   }
 }
 
-export async function verifyJmapAuth(serverUrl: string, authHeader: string): Promise<string> {
+export async function verifyJmapAuth(
+  serverUrl: string,
+  authHeader: string,
+  options: { trusted?: boolean } = {},
+): Promise<string> {
   const normalizedServerUrl = normalizeJmapServerUrl(serverUrl);
   validateProxyAuthHeader(authHeader);
 
+  if (!options.trusted && !(await isPublicHttpUrl(normalizedServerUrl))) {
+    throw new JmapAuthVerificationError('Server URL is not allowed', 400);
+  }
+
   const controller = new AbortController();
   const timeout = setTimeout(() => controller.abort(), VERIFY_TIMEOUT_MS);
 
   try {
-    const response = await fetch(`${normalizedServerUrl}/.well-known/jmap`, {
-      method: 'GET',
-      headers: { Authorization: authHeader },
-      signal: controller.signal,
-    });
+    let currentUrl = `${normalizedServerUrl}/.well-known/jmap`;
+    let response: Response | undefined;
+
+    for (let i = 0; i <= MAX_REDIRECTS; i++) {
+      if (!options.trusted && !(await isPublicHttpUrl(currentUrl))) {
+        throw new JmapAuthVerificationError('Server URL is not allowed', 400);
+      }
+
+      response = await fetch(currentUrl, {
+        method: 'GET',
+        headers: { Authorization: authHeader },
+        signal: controller.signal,
+        redirect: 'manual',
+      });
+
+      if (response.status >= 300 && response.status < 400) {
+        const location = response.headers.get('location');
+        if (!location) {
+          throw new JmapAuthVerificationError('Failed to verify JMAP session', 502);
+        }
+        currentUrl = new URL(location, currentUrl).toString();
+        continue;
+      }
+      break;
+    }
+
+    if (!response) {
+      throw new JmapAuthVerificationError('Failed to verify JMAP session', 502);
+    }
+
+    if (response.status >= 300 && response.status < 400) {
+      throw new JmapAuthVerificationError('Too many redirects verifying JMAP session', 502);
+    }
 
     if (!response.ok) {
       throw new JmapAuthVerificationError(
@@ -77,4 +116,4 @@ export async function verifyJmapAuth(serverUrl: string, authHeader: string): Pro
   } finally {
     clearTimeout(timeout);
   }
-}
+}

lib/birthday-calendar.ts

@@ -30,7 +30,7 @@ export function createBirthdayCalendar(name?: string, color?: string): Calendar
       mayWriteOwn: false,
       mayUpdatePrivate: false,
       mayRSVP: false,
-      mayAdmin: false,
+      mayShare: false,
       mayDelete: false,
     },
   };

lib/demo/demo-client.ts

@@ -78,6 +78,10 @@ export class DemoJMAPClient implements IJMAPClient {
   supportsCalendars(): boolean { return true; }
   supportsSieve(): boolean { return true; }
   supportsFiles(): boolean { return true; }
+  supportsPrincipals(): boolean { return false; }
+  async getPrincipals(): Promise<never[]> { return []; }
+  async setCalendarShare(): Promise<void> { /* demo: no-op */ }
+  async setAddressBookShare(): Promise<void> { /* demo: no-op */ }
 
   // ── Push / state ──────────────────────────────────────────────
 
@@ -91,6 +95,18 @@ export class DemoJMAPClient implements IJMAPClient {
   getLastStates(): AccountStates { return { ...this.lastStates }; }
   setLastStates(states: AccountStates): void { this.lastStates = { ...states }; }
 
+  // PushSubscription endpoints have no meaning in demo mode - the demo client
+  // never makes real network calls so there's nothing for the relay to push to.
+  async listPushSubscriptions() { return []; }
+  async createPushSubscription(): Promise<string> {
+    throw new Error('Push subscriptions are not available in demo mode');
+  }
+  async verifyPushSubscription(): Promise<void> {
+    throw new Error('Push subscriptions are not available in demo mode');
+  }
+  async updatePushSubscription(): Promise<boolean> { return false; }
+  async destroyPushSubscription(): Promise<void> { /* no-op */ }
+
   // ── Quota ─────────────────────────────────────────────────────
 
   async getQuota(): Promise<{ used: number; total: number } | null> {
@@ -379,6 +395,7 @@ export class DemoJMAPClient implements IJMAPClient {
     draftId?: string,
     attachments?: Array<{ blobId: string; name: string; type: string; size: number; disposition?: 'attachment' | 'inline'; cid?: string }>,
     _fromName?: string,
+    htmlBody?: string,
   ): Promise<string> {
     const draftsMb = this.data.mailboxes.find(m => m.role === 'drafts');
     const id = draftId || generateDemoId('email');
@@ -398,9 +415,13 @@ export class DemoJMAPClient implements IJMAPClient {
       sentAt: new Date().toISOString(),
       preview: body.substring(0, 200),
       hasAttachment: !!attachments?.length,
-      textBody: [{ partId: '1', blobId: generateDemoId('blob'), size: body.length, type: 'text/plain' }],
-      htmlBody: [],
-      bodyValues: { '1': { value: body } },
+      textBody: [{ partId: htmlBody ? 'text' : '1', blobId: generateDemoId('blob'), size: body.length, type: 'text/plain' }],
+      htmlBody: htmlBody
+        ? [{ partId: 'html', blobId: generateDemoId('blob'), size: htmlBody.length, type: 'text/html' }]
+        : [],
+      bodyValues: htmlBody
+        ? { text: { value: body }, html: { value: htmlBody } }
+        : { '1': { value: body } },
       attachments: attachments?.map(a => ({ ...a, partId: generateDemoId('part') })),
       messageId: `<${id}@demo.example.com>`,
     };
@@ -426,6 +447,8 @@ export class DemoJMAPClient implements IJMAPClient {
     _fromName?: string,
     htmlBody?: string,
     attachments?: Array<{ blobId: string; name: string; type: string; size: number; disposition?: 'attachment' | 'inline'; cid?: string }>,
+    inReplyTo?: string[],
+    references?: string[],
   ): Promise<void> {
     // Remove draft if updating
     if (draftId) {
@@ -451,6 +474,8 @@ export class DemoJMAPClient implements IJMAPClient {
       bodyValues: htmlBody ? { '1': { value: body }, '2': { value: htmlBody } } : { '1': { value: body } },
       attachments: attachments?.map(a => ({ ...a, partId: generateDemoId('part') })),
       messageId: `<${generateDemoId('msg')}@demo.example.com>`,
+      inReplyTo: inReplyTo?.length ? inReplyTo : undefined,
+      references: references?.length ? references : undefined,
     };
     this.data.emails.push(email);
     this.recalcMailboxCounts();
@@ -552,6 +577,11 @@ export class DemoJMAPClient implements IJMAPClient {
     if (book) Object.assign(book, updates);
   }
 
+  async deleteAddressBook(addressBookId: string): Promise<void> {
+    this.data.addressBooks = this.data.addressBooks.filter(b => b.id !== addressBookId);
+    this.data.contacts = this.data.contacts.filter(c => !c.addressBookIds?.[addressBookId]);
+  }
+
   async getContacts(addressBookId?: string): Promise<ContactCard[]> {
     if (addressBookId) return this.data.contacts.filter(c => c.addressBookIds[addressBookId]);
     return [...this.data.contacts];
@@ -609,7 +639,7 @@ export class DemoJMAPClient implements IJMAPClient {
       includeInAvailability: 'all',
       defaultAlertsWithTime: null, defaultAlertsWithoutTime: null,
       timeZone: null, shareWith: null,
-      myRights: { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true, mayUpdatePrivate: true, mayRSVP: true, mayAdmin: true, mayDelete: true },
+      myRights: { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true, mayUpdatePrivate: true, mayRSVP: true, mayShare: true, mayDelete: true },
       ...calendar,
     } as Calendar;
     this.data.calendars.push(full);

lib/demo/fixtures/calendars.ts

@@ -17,7 +17,7 @@ export function createDemoCalendars(): Calendar[] {
       defaultAlertsWithoutTime: null,
       timeZone: null,
       shareWith: null,
-      myRights: { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true, mayUpdatePrivate: true, mayRSVP: true, mayAdmin: true, mayDelete: false },
+      myRights: { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true, mayUpdatePrivate: true, mayRSVP: true, mayShare: true, mayDelete: false },
     },
     {
       id: 'demo-calendar-work',
@@ -33,7 +33,7 @@ export function createDemoCalendars(): Calendar[] {
       defaultAlertsWithoutTime: null,
       timeZone: null,
       shareWith: null,
-      myRights: { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true, mayUpdatePrivate: true, mayRSVP: true, mayAdmin: true, mayDelete: true },
+      myRights: { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true, mayUpdatePrivate: true, mayRSVP: true, mayShare: true, mayDelete: true },
     },
     {
       id: 'demo-calendar-birthdays',
@@ -49,7 +49,7 @@ export function createDemoCalendars(): Calendar[] {
       defaultAlertsWithoutTime: null,
       timeZone: null,
       shareWith: null,
-      myRights: { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true, mayUpdatePrivate: true, mayRSVP: true, mayAdmin: true, mayDelete: true },
+      myRights: { mayReadFreeBusy: true, mayReadItems: true, mayWriteAll: true, mayWriteOwn: true, mayUpdatePrivate: true, mayRSVP: true, mayShare: true, mayDelete: true },
     },
   ];
 }

lib/email-sanitization.ts

@@ -151,6 +151,7 @@ export function collapseBlockedImageContainers(html: string): string {
         const hasVisibleMedia = el.querySelector('img:not([data-blocked-src]), video, canvas');
         const hasLinks = el.querySelector('a[href]');
         if (!hasVisibleText && !hasVisibleMedia && !hasLinks) {
+          el.setAttribute('data-blocked-collapsed-style', el.style.cssText);
           el.style.display = 'none';
           el.style.height = '0';
           el.style.padding = '0';

lib/email-threading.ts

@@ -0,0 +1,51 @@
+/**
+ * RFC 5322 §3.6.4 reply threading.
+ *
+ * Computes the In-Reply-To and References headers an outgoing reply must
+ * carry so MUAs can stitch the conversation back together.
+ *
+ *   In-Reply-To = parent.Message-ID
+ *   References  = parent.References (if any) + parent.Message-ID
+ *
+ * Bare msg-ids only — angle brackets are stripped because JMAP RFC 8621
+ * §4.1.2.3 stores Message-IDs without them.
+ */
+
+export interface ParentThreadingInfo {
+  // JMAP RFC 8621 §4.1.2.3 specifies messageId as String[]|null, but the
+  // codebase has historically typed it as string. Accept either shape.
+  messageId?: string | string[];
+  references?: string[];
+}
+
+export interface ReplyThreadingHeaders {
+  inReplyTo: string[];
+  references: string[];
+}
+
+export function stripMessageIdBrackets(id: string): string {
+  return id.trim().replace(/^<+/, '').replace(/>+$/, '').trim();
+}
+
+export function computeReplyThreadingHeaders(
+  parent: ParentThreadingInfo | undefined,
+): ReplyThreadingHeaders | null {
+  const rawId = Array.isArray(parent?.messageId) ? parent.messageId[0] : parent?.messageId;
+  const parentId = rawId ? stripMessageIdBrackets(rawId) : '';
+  if (!parentId) return null;
+
+  const ancestors = (parent?.references ?? [])
+    .map(stripMessageIdBrackets)
+    .filter(Boolean);
+
+  // De-dupe while preserving order; the parent's id closes the chain.
+  const seen = new Set<string>();
+  const references: string[] = [];
+  for (const id of [...ancestors, parentId]) {
+    if (seen.has(id)) continue;
+    seen.add(id);
+    references.push(id);
+  }
+
+  return { inReplyTo: [parentId], references };
+}

lib/jmap/client-interface.ts

@@ -1,4 +1,4 @@
-import type { Email, Mailbox, StateChange, AccountStates, Thread, Identity, EmailAddress, ContactCard, AddressBook, VacationResponse, Calendar, CalendarEvent, CalendarEventFilter, CalendarTask, FileNode } from "./types";
+import type { Email, Mailbox, StateChange, AccountStates, Thread, Identity, EmailAddress, ContactCard, AddressBook, AddressBookRights, VacationResponse, Calendar, CalendarRights, CalendarEvent, CalendarEventFilter, CalendarTask, FileNode, Principal, PushSubscription } from "./types";
 import type { SieveScript, SieveCapabilities } from "./sieve-types";
 
 /**
@@ -51,6 +51,20 @@ export interface IJMAPClient {
   getLastStates(): AccountStates;
   setLastStates(states: AccountStates): void;
 
+  // ── PushSubscription (RFC 8620 §7.2) ───────────────────────────
+  // Browser-driven Web Push setup: register a relay URL the JMAP server can
+  // forward StateChange events to. Mobile uses the same primitives.
+  listPushSubscriptions(): Promise<PushSubscription[]>;
+  createPushSubscription(params: {
+    deviceClientId: string;
+    url: string;
+    types: string[];
+    expires?: string;
+  }): Promise<string>;
+  verifyPushSubscription(id: string, verificationCode: string): Promise<void>;
+  updatePushSubscription(id: string, patch: { expires?: string; types?: string[] }): Promise<boolean>;
+  destroyPushSubscription(id: string): Promise<void>;
+
   // ── Quota ─────────────────────────────────────────────────────
   getQuota(): Promise<{ used: number; total: number } | null>;
 
@@ -115,6 +129,7 @@ export interface IJMAPClient {
     draftId?: string,
     attachments?: Array<{ blobId: string; name: string; type: string; size: number; disposition?: 'attachment' | 'inline'; cid?: string }>,
     fromName?: string,
+    htmlBody?: string,
   ): Promise<string>;
 
   sendEmail(
@@ -129,6 +144,8 @@ export interface IJMAPClient {
     fromName?: string,
     htmlBody?: string,
     attachments?: Array<{ blobId: string; name: string; type: string; size: number; disposition?: 'attachment' | 'inline'; cid?: string }>,
+    inReplyTo?: string[],
+    references?: string[],
   ): Promise<void>;
 
   sendImipReply(opts: {
@@ -190,6 +207,7 @@ export interface IJMAPClient {
   getAllAddressBooks(): Promise<AddressBook[]>;
   createAddressBook(name: string): Promise<AddressBook>;
   updateAddressBook(addressBookId: string, updates: Partial<AddressBook>, targetAccountId?: string): Promise<void>;
+  deleteAddressBook(addressBookId: string, targetAccountId?: string): Promise<void>;
   getContacts(addressBookId?: string): Promise<ContactCard[]>;
   getAllContacts(): Promise<ContactCard[]>;
   getContact(contactId: string, accountId?: string): Promise<ContactCard | null>;
@@ -227,6 +245,12 @@ export interface IJMAPClient {
   updateCalendarTask(taskId: string, updates: Partial<CalendarTask>, targetAccountId?: string): Promise<void>;
   deleteCalendarTask(taskId: string, targetAccountId?: string): Promise<void>;
 
+  // ── Sharing (RFC 9670 Principals) ─────────────────────────────
+  supportsPrincipals(): boolean;
+  getPrincipals(targetAccountId?: string): Promise<Principal[]>;
+  setCalendarShare(calendarId: string, principalId: string, rights: CalendarRights | null, targetAccountId?: string): Promise<void>;
+  setAddressBookShare(addressBookId: string, principalId: string, rights: AddressBookRights | null, targetAccountId?: string): Promise<void>;
+
   // ── Sieve / Filters ──────────────────────────────────────────
   getSieveAccountId(): string;
   getSieveCapabilities(): SieveCapabilities | null;

lib/jmap/client.ts

@@ -1,4 +1,4 @@
-import type { Email, Mailbox, StateChange, AccountStates, Thread, Identity, EmailAddress, ContactCard, AddressBook, VacationResponse, Calendar, CalendarEvent, CalendarEventFilter, CalendarTask, FileNode, FileNodeFilter } from "./types";
+import type { Email, Mailbox, StateChange, AccountStates, Thread, Identity, EmailAddress, ContactCard, AddressBook, AddressBookRights, VacationResponse, Calendar, CalendarRights, CalendarEvent, CalendarEventFilter, CalendarTask, FileNode, FileNodeFilter, Principal, PushSubscription } from "./types";
 import type { SieveScript, SieveCapabilities } from "./sieve-types";
 import type { IJMAPClient } from "./client-interface";
 import { toWildcardQuery } from "./search-utils";
@@ -294,6 +294,12 @@ function foldIcsLine(line: string): string {
   return chunks.join('\r\n');
 }
 
+// JMAP RFC 8621 stores Message-IDs without angle brackets. Strip any that
+// snuck in (e.g. when echoing values that originated from RFC 5322 headers).
+function stripMessageIdBrackets(id: string): string {
+  return id.trim().replace(/^<+/, '').replace(/>+$/, '').trim();
+}
+
 export class JMAPClient implements IJMAPClient {
   private static readonly RATE_LIMIT_TOAST_THROTTLE_MS = 10_000;
 
@@ -1933,7 +1939,8 @@ export class JMAPClient implements IJMAPClient {
     fromEmail?: string,
     draftId?: string,
     attachments?: Array<{ blobId: string; name: string; type: string; size: number; disposition?: 'attachment' | 'inline'; cid?: string }>,
-    fromName?: string
+    fromName?: string,
+    htmlBody?: string
   ): Promise<string> {
     const mailboxes = await this.getMailboxes();
     const draftsMailbox = mailboxes.find(mb => mb.role === 'drafts');
@@ -1952,7 +1959,8 @@ export class JMAPClient implements IJMAPClient {
       keywords: Record<string, boolean>;
       mailboxIds: Record<string, boolean>;
       bodyValues: Record<string, { value: string }>;
-      textBody: { partId: string }[];
+      textBody: { partId: string; type?: string }[];
+      htmlBody?: { partId: string; type: string }[];
       attachments?: { blobId: string; type: string; name: string; disposition: string; cid?: string }[];
     }
 
@@ -1964,8 +1972,13 @@ export class JMAPClient implements IJMAPClient {
       subject,
       keywords: { "$draft": true },
       mailboxIds: { [draftsMailbox.id]: true },
-      bodyValues: { "1": { value: body } },
-      textBody: [{ partId: "1" }],
+      bodyValues: htmlBody
+        ? { "text": { value: body }, "html": { value: htmlBody } }
+        : { "1": { value: body } },
+      textBody: htmlBody
+        ? [{ partId: "text", type: "text/plain" }]
+        : [{ partId: "1" }],
+      ...(htmlBody ? { htmlBody: [{ partId: "html", type: "text/html" }] } : {}),
     };
 
     if (attachments?.length) {
@@ -2027,7 +2040,9 @@ export class JMAPClient implements IJMAPClient {
     draftId?: string,
     fromName?: string,
     htmlBody?: string,
-    attachments?: Array<{ blobId: string; name: string; type: string; size: number; disposition?: 'attachment' | 'inline'; cid?: string }>
+    attachments?: Array<{ blobId: string; name: string; type: string; size: number; disposition?: 'attachment' | 'inline'; cid?: string }>,
+    inReplyTo?: string[],
+    references?: string[]
   ): Promise<void> {
     const emailId = `send-${Date.now()}`;
     const mailboxes = await this.getMailboxes();
@@ -2067,6 +2082,11 @@ export class JMAPClient implements IJMAPClient {
       }
     }
 
+    // Per RFC 8621 §4.1.2.3 inReplyTo/references are arrays of bare msg-ids
+    // (no angle brackets). Stalwart may return them either way, so normalize.
+    const normalizedInReplyTo = inReplyTo?.map(stripMessageIdBrackets).filter(Boolean);
+    const normalizedReferences = references?.map(stripMessageIdBrackets).filter(Boolean);
+
     // Always create a new email with the final body content
     const emailCreate: Record<string, unknown> = {
       from: [{ ...(fromName ? { name: fromName } : {}), email: fromEmail || this.username }],
@@ -2075,6 +2095,8 @@ export class JMAPClient implements IJMAPClient {
       cc: cc?.map(email => ({ email })),
       bcc: bcc?.map(email => ({ email })),
       subject,
+      inReplyTo: normalizedInReplyTo?.length ? normalizedInReplyTo : undefined,
+      references: normalizedReferences?.length ? normalizedReferences : undefined,
       keywords: { "$seen": true, "$draft": true },
       mailboxIds: { [draftsMailbox.id]: true },
     };
@@ -2826,6 +2848,10 @@ export class JMAPClient implements IJMAPClient {
     return this.hasCapability("urn:ietf:params:jmap:sieve");
   }
 
+  supportsPrincipals(): boolean {
+    return this.hasCapability("urn:ietf:params:jmap:principals");
+  }
+
   getSieveAccountId(): string {
     const sieveAccount = this.session?.primaryAccounts?.["urn:ietf:params:jmap:sieve"];
     return sieveAccount || this.accountId;
@@ -3198,6 +3224,102 @@ export class JMAPClient implements IJMAPClient {
     throw new Error("Failed to update address book");
   }
 
+  async deleteAddressBook(addressBookId: string, targetAccountId?: string): Promise<void> {
+    const accountId = targetAccountId || this.getContactsAccountId();
+    const response = await this.request([
+      ["AddressBook/set", { accountId, destroy: [addressBookId] }, "0"],
+    ], this.contactUsing());
+
+    const result = response.methodResponses?.[0]?.[1];
+    if (result?.notDestroyed?.[addressBookId]) {
+      const err = result.notDestroyed[addressBookId];
+      throw new Error(err.description || "Failed to delete address book");
+    }
+  }
+
+  // ── Sharing (RFC 9670) ──────────────────────────────────────────────────────
+
+  private principalsUsing(): string[] {
+    return ["urn:ietf:params:jmap:core", "urn:ietf:params:jmap:principals"];
+  }
+
+  /**
+   * List all principals visible to the user (RFC 9670). Stalwart returns the
+   * full directory regardless of `filter`, so we fetch the whole list and let
+   * callers filter client-side.
+   */
+  async getPrincipals(targetAccountId?: string): Promise<Principal[]> {
+    if (!this.supportsPrincipals()) return [];
+    const accountId = targetAccountId || this.accountId;
+    try {
+      const response = await this.request([
+        ["Principal/query", { accountId }, "0"],
+        ["Principal/get", {
+          accountId,
+          "#ids": { resultOf: "0", name: "Principal/query", path: "/ids" },
+        }, "1"],
+      ], this.principalsUsing());
+
+      const getResp = response.methodResponses?.find((r) => r[0] === "Principal/get");
+      if (!getResp) return [];
+      const list = (getResp[1].list || []) as Principal[];
+      return list.map((p) => ({ ...p, accountId }));
+    } catch (error) {
+      console.error("Failed to fetch principals:", error);
+      return [];
+    }
+  }
+
+  /**
+   * Add, update, or remove a principal's rights on a calendar.
+   * Pass `rights: null` to revoke access.
+   */
+  async setCalendarShare(
+    calendarId: string,
+    principalId: string,
+    rights: CalendarRights | null,
+    targetAccountId?: string,
+  ): Promise<void> {
+    const accountId = targetAccountId || this.getCalendarsAccountId();
+    const response = await this.request([
+      ["Calendar/set", {
+        accountId,
+        update: { [calendarId]: { [`shareWith/${principalId}`]: rights } },
+      }, "0"],
+    ], this.calendarUsing());
+
+    const result = response.methodResponses?.[0]?.[1];
+    if (result?.notUpdated?.[calendarId]) {
+      const err = result.notUpdated[calendarId];
+      throw new Error(err.description || "Failed to update calendar share");
+    }
+  }
+
+  /**
+   * Add, update, or remove a principal's rights on an address book.
+   * Pass `rights: null` to revoke access.
+   */
+  async setAddressBookShare(
+    addressBookId: string,
+    principalId: string,
+    rights: AddressBookRights | null,
+    targetAccountId?: string,
+  ): Promise<void> {
+    const accountId = targetAccountId || this.getContactsAccountId();
+    const response = await this.request([
+      ["AddressBook/set", {
+        accountId,
+        update: { [addressBookId]: { [`shareWith/${principalId}`]: rights } },
+      }, "0"],
+    ], this.contactUsing());
+
+    const result = response.methodResponses?.[0]?.[1];
+    if (result?.notUpdated?.[addressBookId]) {
+      const err = result.notUpdated[addressBookId];
+      throw new Error(err.description || "Failed to update address book share");
+    }
+  }
+
   private async fetchPaginatedContacts(
     accountId: string,
     filter?: Record<string, unknown>,
@@ -5191,4 +5313,80 @@ export class JMAPClient implements IJMAPClient {
       }
     }
   }
+
+  // ── PushSubscription (RFC 8620 §7.2) ──────────────────────────────
+  // Used by the PWA Web Push integration. The mobile app does the same dance
+  // through its own JMAP client - keep these in sync.
+
+  async listPushSubscriptions(): Promise<PushSubscription[]> {
+    const response = await this.request(
+      [['PushSubscription/get', { ids: null }, '0']],
+      ['urn:ietf:params:jmap:core'],
+    );
+    const [, body] = response.methodResponses[0] ?? [];
+    return ((body as { list?: PushSubscription[] } | undefined)?.list) ?? [];
+  }
+
+  async createPushSubscription(params: {
+    deviceClientId: string;
+    url: string;
+    types: string[];
+    expires?: string;
+  }): Promise<string> {
+    const created: Record<string, unknown> = {
+      deviceClientId: params.deviceClientId,
+      url: params.url,
+      types: params.types,
+    };
+    if (params.expires) created.expires = params.expires;
+
+    const response = await this.request(
+      [['PushSubscription/set', { create: { new: created } }, '0']],
+      ['urn:ietf:params:jmap:core'],
+    );
+    const [, body] = response.methodResponses[0] ?? [];
+    const result = (body as { created?: { new?: { id?: string } }; notCreated?: { new?: unknown } } | undefined);
+    const id = result?.created?.new?.id;
+    if (!id) {
+      throw new Error(
+        `PushSubscription/set create failed: ${JSON.stringify(result?.notCreated?.new ?? body)}`,
+      );
+    }
+    return id;
+  }
+
+  async verifyPushSubscription(id: string, verificationCode: string): Promise<void> {
+    const response = await this.request(
+      [['PushSubscription/set', { update: { [id]: { verificationCode } } }, '0']],
+      ['urn:ietf:params:jmap:core'],
+    );
+    const [, body] = response.methodResponses[0] ?? [];
+    const notUpdated = (body as { notUpdated?: Record<string, unknown> } | undefined)?.notUpdated?.[id];
+    if (notUpdated) {
+      throw new Error(`PushSubscription verification failed: ${JSON.stringify(notUpdated)}`);
+    }
+  }
+
+  // Returns false when the server rejects the update (e.g. the subscription
+  // was already destroyed) - the caller treats that as a signal to recreate.
+  async updatePushSubscription(
+    id: string,
+    patch: { expires?: string; types?: string[] },
+  ): Promise<boolean> {
+    const response = await this.request(
+      [['PushSubscription/set', { update: { [id]: patch } }, '0']],
+      ['urn:ietf:params:jmap:core'],
+    );
+    const [, body] = response.methodResponses[0] ?? [];
+    const r = body as { updated?: Record<string, unknown>; notUpdated?: Record<string, unknown> } | undefined;
+    if (r?.notUpdated?.[id]) return false;
+    return r?.updated?.[id] !== undefined;
+  }
+
+  async destroyPushSubscription(id: string): Promise<void> {
+    await this.request(
+      [['PushSubscription/set', { destroy: [id] }, '0']],
+      ['urn:ietf:params:jmap:core'],
+    );
+  }
 }

lib/jmap/types.ts

@@ -368,6 +368,7 @@ export interface AddressBook {
   isDefault?: boolean;
   isSubscribed?: boolean;
   myRights?: AddressBookRights;
+  shareWith?: Record<string, AddressBookRights> | null;
   accountId?: string;
   accountName?: string;
   isShared?: boolean;
@@ -376,10 +377,22 @@ export interface AddressBook {
 export interface AddressBookRights {
   mayRead: boolean;
   mayWrite: boolean;
-  mayShare: boolean;
+  mayShare?: boolean;
   mayDelete: boolean;
 }
 
+// JMAP Principals (RFC 9670)
+export interface Principal {
+  id: string;
+  type: 'individual' | 'group' | 'resource' | 'location' | 'other';
+  name: string;
+  description?: string | null;
+  email?: string | null;
+  timeZone?: string | null;
+  capabilities?: Record<string, unknown>;
+  accountId?: string;
+}
+
 export interface VacationResponse {
   id: string;
   isEnabled: boolean;
@@ -442,7 +455,7 @@ export interface CalendarRights {
   mayWriteOwn: boolean;
   mayUpdatePrivate: boolean;
   mayRSVP: boolean;
-  mayAdmin: boolean;
+  mayShare: boolean;
   mayDelete: boolean;
 }
 

lib/oauth/discovery.ts

@@ -7,8 +7,21 @@ export interface OAuthMetadata {
 }
 
 const CACHE_TTL_MS = 10 * 60 * 1000;
+const CACHE_MAX_ENTRIES = 64;
 const metadataCache = new Map<string, { metadata: OAuthMetadata; expiresAt: number }>();
 
+function rememberMetadata(serverUrl: string, metadata: OAuthMetadata): void {
+  // Bound the cache so callers that can supply arbitrary serverUrl values
+  // (e.g. unauthenticated routes that fall back to user input) cannot
+  // exhaust memory. Map preserves insertion order, so the oldest entry is
+  // always the first one yielded by keys().
+  if (metadataCache.size >= CACHE_MAX_ENTRIES) {
+    const oldest = metadataCache.keys().next().value;
+    if (oldest !== undefined) metadataCache.delete(oldest);
+  }
+  metadataCache.set(serverUrl, { metadata, expiresAt: Date.now() + CACHE_TTL_MS });
+}
+
 export async function discoverOAuth(serverUrl: string): Promise<OAuthMetadata | null> {
   const cached = metadataCache.get(serverUrl);
   if (cached && cached.expiresAt > Date.now()) return cached.metadata;
@@ -38,7 +51,7 @@ export async function discoverOAuth(serverUrl: string): Promise<OAuthMetadata |
           revocation_endpoint: data.revocation_endpoint,
           end_session_endpoint: data.end_session_endpoint,
         };
-        metadataCache.set(serverUrl, { metadata, expiresAt: Date.now() + CACHE_TTL_MS });
+        rememberMetadata(serverUrl, metadata);
         return metadata;
       }
       errors.push(`${url} response missing required endpoints`);

lib/plugin-api.ts

@@ -121,6 +121,7 @@ export interface PluginAPI {
     registerSettingsSection: (section: SettingsSection) => Disposable;
     registerComposerAction: (action: ComposerAction) => Disposable;
     registerSidebarWidget: (widget: SidebarWidget) => Disposable;
+    registerComposerSidebar: (widget: SidebarWidget) => Disposable;
     registerDetailSidebar: (widget: SidebarWidget) => Disposable;
     registerContextMenuItem: (item: ContextMenuItem) => Disposable;
     registerNavigationRailItem: (component: React.ComponentType) => Disposable;
@@ -609,6 +610,12 @@ export function createPluginAPI(plugin: InstalledPlugin): PluginAPI {
         return registerSlot(plugin.id, 'sidebar-widget', widget.render as React.ComponentType<Record<string, unknown>>, widget.order ?? 100);
       },
 
+      registerComposerSidebar: (widget: SidebarWidget) => {
+        requirePermission(plugin, 'ui:composer-sidebar');
+        const slot = widget.side === 'right' ? 'composer-sidebar-right' : 'composer-sidebar';
+        return registerSlot(plugin.id, slot, widget.render as React.ComponentType<Record<string, unknown>>, widget.order ?? 100);
+      },
+
       registerDetailSidebar: (widget: SidebarWidget) => {
         requirePermission(plugin, 'ui:sidebar-widget');
         return registerSlot(plugin.id, 'email-detail-sidebar', widget.render as React.ComponentType<Record<string, unknown>>, widget.order ?? 100);

lib/plugin-hooks.ts

@@ -365,6 +365,18 @@ export const themeHooks = {
   onThemeChange: new HookBus(),
   onCustomThemeChange: new HookBus(),
   onLocaleChange: new HookBus(),
+  /**
+   * Transform hook fired immediately before a theme's compiled CSS is
+   * injected into the document.
+   *
+   *   handler(css: string, ctx: { themeId: string | null; variant: 'light' | 'dark' }): string | undefined
+   *
+   * Return a new CSS string to override what gets injected, or `undefined`
+   * to pass through unchanged. Use this to inject extra `@font-face` rules,
+   * patch a third-party theme's variables for accessibility, or implement
+   * site-wide design-token overrides.
+   */
+  onThemeBeforeApply: new HookBus(),
 };
 
 // §7.15 Toast Hooks

lib/plugin-storage.ts

@@ -1,9 +1,11 @@
 // IndexedDB storage for plugin/theme binary blobs (JS bundles, CSS, previews)
 
 const DB_NAME = 'bulwark-plugins';
-const DB_VERSION = 1;
+// Bumped to 2 to add the theme-skin store; existing stores are preserved.
+const DB_VERSION = 2;
 const STORE_PLUGINS = 'plugin-code';
 const STORE_THEMES = 'theme-css';
+const STORE_THEME_SKINS = 'theme-skin';
 const STORE_PREVIEWS = 'previews';
 
 function openDB(): Promise<IDBDatabase> {
@@ -18,6 +20,9 @@ function openDB(): Promise<IDBDatabase> {
       if (!db.objectStoreNames.contains(STORE_THEMES)) {
         db.createObjectStore(STORE_THEMES);
       }
+      if (!db.objectStoreNames.contains(STORE_THEME_SKINS)) {
+        db.createObjectStore(STORE_THEME_SKINS);
+      }
       if (!db.objectStoreNames.contains(STORE_PREVIEWS)) {
         db.createObjectStore(STORE_PREVIEWS);
       }
@@ -83,6 +88,18 @@ export const pluginStorage = {
     await deleteItem(STORE_THEMES, themeId);
   },
 
+  // Theme skin CSS - separate store so it can be present/absent independently
+  // of the colour-token CSS (e.g. some v2 themes ship colours only).
+  async saveThemeSkin(themeId: string, skin: string): Promise<void> {
+    await putItem(STORE_THEME_SKINS, themeId, skin);
+  },
+  async getThemeSkin(themeId: string): Promise<string | null> {
+    return getItem<string>(STORE_THEME_SKINS, themeId);
+  },
+  async deleteThemeSkin(themeId: string): Promise<void> {
+    await deleteItem(STORE_THEME_SKINS, themeId);
+  },
+
   // Preview images (stored as data URIs)
   async savePreview(id: string, dataUri: string): Promise<void> {
     await putItem(STORE_PREVIEWS, id, dataUri);

lib/plugin-types.ts

@@ -11,6 +11,41 @@ export type ThemeVariant = 'light' | 'dark';
 
 // ─── Manifests ───────────────────────────────────────────────
 
+/**
+ * Advanced theme fields ("Theme API v2"). All optional and additive - a
+ * legacy theme that ships only `:root`/`.dark` CSS continues to work.
+ *
+ * When `apiVersion >= 2` (or any of `tokens`/`extends`/`derive`/`density`/
+ * `radii`/`typography` is present), the theme compiler runs at install time
+ * and produces a single CSS string from the structured fields, optionally
+ * concatenated with a hand-written `theme.css` for fine-grained overrides.
+ */
+export interface ThemeTokenSet {
+  /** Tokens applied regardless of variant (emitted into `:root`). */
+  common?: Record<string, string>;
+  /** Tokens applied in light mode (emitted into `:root`). */
+  light?: Record<string, string>;
+  /** Tokens applied in dark mode (emitted into `.dark`). */
+  dark?: Record<string, string>;
+}
+
+export type ThemeDensity = 'compact' | 'normal' | 'touch';
+
+export interface ThemeRadii {
+  sm?: string;
+  md?: string;
+  lg?: string;
+  xl?: string;
+  full?: string;
+}
+
+export interface ThemeTypography {
+  fontSans?: string;
+  fontMono?: string;
+  fontDisplay?: string;
+  baseFontSize?: string;
+}
+
 export interface ThemeManifest {
   id: string;
   name: string;
@@ -21,6 +56,22 @@ export interface ThemeManifest {
   preview?: string;
   variants: ThemeVariant[];
   minAppVersion?: string;
+
+  // ─── Advanced (Theme API v2) ─────────────────────────────────
+  /** Theme API version. Defaults to 1 (raw-CSS only). */
+  apiVersion?: 1 | 2;
+  /** Inherit tokens/CSS from another installed (or built-in) theme by id. */
+  extends?: string;
+  /** Structured colour tokens - compiled into CSS at install time. */
+  tokens?: ThemeTokenSet;
+  /** When true, missing standard tokens are derived (e.g. *-foreground from contrast). */
+  derive?: boolean;
+  /** Default UI density preset (compact / normal / touch). */
+  density?: ThemeDensity;
+  /** Border-radius scale, emitted as `--radius-*` vars. */
+  radii?: ThemeRadii;
+  /** Font stacks + base size, emitted as `--font-*` vars. */
+  typography?: ThemeTypography;
 }
 
 export interface PluginManifest {
@@ -41,6 +92,14 @@ export interface PluginManifest {
    * so plugins can use api.i18n.t() without calling addTranslations() first.
    */
   locales?: Record<string, Record<string, string>>;
+  /**
+   * External origins this plugin may embed in iframes (e.g. for YouTube,
+   * Vimeo, Jitsi). Each entry is a single CSP origin like
+   *   "https://www.youtube-nocookie.com"
+   *   "https://*.example.com:8443"
+   * Validated at install time and merged into the host CSP `frame-src`.
+   */
+  frameOrigins?: string[];
 }
 
 export interface SettingFieldSchema {
@@ -62,12 +121,29 @@ export interface InstalledTheme {
   author: string;
   description: string;
   preview?: string;       // data: URI or blob URL
-  css: string;            // raw CSS text
+  css: string;            // compiled CSS text - what gets injected
+  /**
+   * Optional "skin" CSS shipped by Theme API v2 themes that need to restyle
+   * actual UI components (toolbars, lists, buttons, etc.) - not just colour
+   * tokens. Injected into a separate `<style>` tag so it can be stripped
+   * cleanly when the theme is deactivated. Stored in IndexedDB with the same
+   * lifecycle as `css` to keep localStorage small.
+   */
+  skin?: string;
   variants: ThemeVariant[];
   enabled: boolean;
   builtIn: boolean;
   managed?: boolean;
   forceEnabled?: boolean;
+
+  // ─── Advanced (Theme API v2) ─ carried over from the manifest ─
+  apiVersion?: 1 | 2;
+  extends?: string;
+  tokens?: ThemeTokenSet;
+  derive?: boolean;
+  density?: ThemeDensity;
+  radii?: ThemeRadii;
+  typography?: ThemeTypography;
 }
 
 export interface InstalledPlugin {
@@ -101,6 +177,8 @@ export type SlotName =
   | 'email-banner'
   | 'email-footer'
   | 'composer-toolbar'
+  | 'composer-sidebar'
+  | 'composer-sidebar-right'
   | 'sidebar-widget'
   | 'email-detail-sidebar'
   | 'settings-section'
@@ -150,6 +228,12 @@ export interface SidebarWidget {
   label: string;
   render: React.ComponentType;
   order?: number;
+  /**
+   * For composer sidebars, choose which side of the New Message dialog the
+   * panel renders on. Defaults to `'left'` for backwards compatibility.
+   * Ignored by other sidebar slots.
+   */
+  side?: 'left' | 'right';
 }
 
 export interface ContextMenuItem {
@@ -495,7 +579,8 @@ export const ALL_PERMISSIONS = [
   'auth:observe',
   'http:post',
   'ui:observe', 'ui:toolbar', 'ui:email-banner', 'ui:email-footer',
-  'ui:composer-toolbar', 'ui:sidebar-widget', 'ui:settings-section',
+  'ui:composer-toolbar', 'ui:composer-sidebar',
+  'ui:sidebar-widget', 'ui:settings-section',
   'ui:context-menu', 'ui:navigation-rail', 'ui:keyboard',
   'ui:calendar-action', 'ui:admin-page',
   'admin:config',
@@ -510,7 +595,13 @@ export const IMPLICIT_PERMISSIONS: Permission[] = ['ui:observe', 'app:lifecycle'
 // ─── Validation ──────────────────────────────────────────────
 
 export const MAX_PLUGIN_SIZE = 5 * 1024 * 1024; // 5 MB
-export const MAX_THEME_SIZE = 1 * 1024 * 1024;  // 1 MB
+export const MAX_THEME_SIZE = 2 * 1024 * 1024;  // 2 MB (was 1 MB; v2 themes may ship a skin.css)
+/**
+ * Maximum size of an individual `skin.css` payload after extraction.
+ * Skins are component-level CSS, not images - anything bigger than this is
+ * almost certainly bundling assets the validator will refuse anyway.
+ */
+export const MAX_THEME_SKIN_BYTES = 256 * 1024; // 256 KB
 
 export const ALLOWED_PLUGIN_FILES = new Set([
   '.js', '.mjs', '.css', '.json', '.png', '.svg', '.woff2', '.jpg', '.jpeg', '.webp',

lib/plugin-validator.ts

@@ -8,9 +8,11 @@ import {
   ALL_PERMISSIONS,
   MAX_PLUGIN_SIZE,
   MAX_THEME_SIZE,
+  MAX_THEME_SKIN_BYTES,
   ALLOWED_PLUGIN_FILES,
 } from './plugin-types';
-import { sanitizeThemeCSS, validateThemeCSSSafety } from './theme-loader';
+import { sanitizeThemeCSS, sanitizeSkinCSS, validateThemeCSSSafety } from './theme-loader';
+import { compileAdvancedTheme, isAdvancedManifest } from './theme-compiler';
 
 export interface ValidationResult {
   valid: boolean;
@@ -21,6 +23,11 @@ export interface ValidationResult {
 export interface ThemeExtractionResult extends ValidationResult {
   manifest: ThemeManifest | null;
   css: string;
+  /**
+   * Optional skin CSS - component-level overrides extracted from `skin.css`.
+   * Only populated for Theme API v2 manifests; v1 themes ignore the file.
+   */
+  skin: string | null;
   preview: string | null; // data URI
 }
 
@@ -63,6 +70,29 @@ function validateThemeManifest(manifest: Record<string, unknown>): { result: The
     if (!valid) errors.push('Variants must be "light" or "dark"');
   }
 
+  // ── Theme API v2 fields (all optional) ──
+  if (manifest.apiVersion !== undefined && manifest.apiVersion !== 1 && manifest.apiVersion !== 2) {
+    errors.push('"apiVersion" must be 1 or 2 if present');
+  }
+  if (manifest.extends !== undefined && typeof manifest.extends !== 'string') {
+    errors.push('"extends" must be a string (the parent theme id)');
+  }
+  if (manifest.tokens !== undefined && (typeof manifest.tokens !== 'object' || manifest.tokens === null)) {
+    errors.push('"tokens" must be an object with optional "common"/"light"/"dark" maps');
+  }
+  if (manifest.density !== undefined && !['compact', 'normal', 'touch'].includes(manifest.density as string)) {
+    errors.push('"density" must be "compact", "normal", or "touch"');
+  }
+  if (manifest.derive !== undefined && typeof manifest.derive !== 'boolean') {
+    errors.push('"derive" must be a boolean');
+  }
+  if (manifest.radii !== undefined && (typeof manifest.radii !== 'object' || manifest.radii === null)) {
+    errors.push('"radii" must be an object');
+  }
+  if (manifest.typography !== undefined && (typeof manifest.typography !== 'object' || manifest.typography === null)) {
+    errors.push('"typography" must be an object');
+  }
+
   if (errors.length > 0) return { result: null, errors };
 
   return {
@@ -157,7 +187,12 @@ export async function extractTheme(file: File): Promise<ThemeExtractionResult> {
 
   // Size check
   if (file.size > MAX_THEME_SIZE) {
-    return { valid: false, errors: ['Theme ZIP exceeds 1 MB size limit'], warnings: [], manifest: null, css: '', preview: null };
+    return {
+      valid: false,
+      errors: [`Theme ZIP exceeds ${Math.round(MAX_THEME_SIZE / (1024 * 1024))} MB size limit`],
+      warnings: [],
+      manifest: null, css: '', skin: null, preview: null,
+    };
   }
 
   let zip: JSZip;
@@ -165,7 +200,7 @@ export async function extractTheme(file: File): Promise<ThemeExtractionResult> {
     const buffer = await file.arrayBuffer();
     zip = await JSZip.loadAsync(buffer);
   } catch {
-    return { valid: false, errors: ['Invalid ZIP file'], warnings: [], manifest: null, css: '', preview: null };
+    return { valid: false, errors: ['Invalid ZIP file'], warnings: [], manifest: null, css: '', skin: null, preview: null };
   }
 
   const root = findZipRoot(zip);
@@ -173,7 +208,7 @@ export async function extractTheme(file: File): Promise<ThemeExtractionResult> {
   // Read manifest
   const manifestFile = zip.file(root + 'manifest.json');
   if (!manifestFile) {
-    return { valid: false, errors: ['Missing manifest.json'], warnings: [], manifest: null, css: '', preview: null };
+    return { valid: false, errors: ['Missing manifest.json'], warnings: [], manifest: null, css: '', skin: null, preview: null };
   }
 
   let manifestData: Record<string, unknown>;
@@ -181,28 +216,49 @@ export async function extractTheme(file: File): Promise<ThemeExtractionResult> {
     const raw = await manifestFile.async('string');
     manifestData = JSON.parse(raw);
   } catch {
-    return { valid: false, errors: ['Invalid manifest.json (not valid JSON)'], warnings: [], manifest: null, css: '', preview: null };
+    return { valid: false, errors: ['Invalid manifest.json (not valid JSON)'], warnings: [], manifest: null, css: '', skin: null, preview: null };
   }
 
   const { result: manifest, errors: manifestErrors } = validateThemeManifest(manifestData);
   errors.push(...manifestErrors);
   if (!manifest) {
-    return { valid: false, errors, warnings, manifest: null, css: '', preview: null };
+    return { valid: false, errors, warnings, manifest: null, css: '', skin: null, preview: null };
   }
 
-  // Read theme.css
+  // Read theme.css - required for v1 themes, optional when the manifest
+  // declares Theme API v2 fields (tokens/extends/derive/density/radii/typography),
+  // since the compiler can produce CSS purely from the manifest.
   const cssFile = zip.file(root + 'theme.css');
-  if (!cssFile) {
+  const isAdvanced = isAdvancedManifest(manifest);
+
+  let userCSS = '';
+  if (cssFile) {
+    userCSS = await cssFile.async('string');
+    const safety = validateThemeCSSSafety(userCSS);
+    if (!safety.valid) {
+      // Sanitize instead of rejecting
+      const sanitized = sanitizeThemeCSS(userCSS);
+      userCSS = sanitized.css;
+      warnings.push(...sanitized.warnings);
+    }
+  } else if (!isAdvanced) {
     errors.push('Missing theme.css');
-    return { valid: false, errors, warnings, manifest, css: '', preview: null };
+    return { valid: false, errors, warnings, manifest, css: '', skin: null, preview: null };
   }
 
-  let rawCSS = await cssFile.async('string');
+  // Compile advanced tokens into CSS (for v2 manifests). The compiled output
+  // is concatenated with any user-supplied theme.css for fine-grained overrides.
+  let rawCSS = userCSS;
+  if (isAdvanced) {
+    const compiled = compileAdvancedTheme(manifest, { userCSS });
+    if (compiled.errors.length > 0) {
+      errors.push(...compiled.errors);
+      return { valid: false, errors, warnings, manifest, css: '', skin: null, preview: null };
+    }
+    warnings.push(...compiled.warnings);
+    rawCSS = compiled.css;
 
-  // Validate CSS safety
-  const safety = validateThemeCSSSafety(rawCSS);
-  if (!safety.valid) {
-    // Sanitize instead of rejecting
+    // Run sanitizer over the final compiled output as a defence-in-depth check.
     const sanitized = sanitizeThemeCSS(rawCSS);
     rawCSS = sanitized.css;
     warnings.push(...sanitized.warnings);
@@ -222,12 +278,33 @@ export async function extractTheme(file: File): Promise<ThemeExtractionResult> {
     }
   }
 
+  // Read skin.css if present (Theme API v2 only). Skins target real
+  // component selectors and bypass the strict :root/.dark selector check -
+  // they still go through the dangerous-pattern sanitizer.
+  let skin: string | null = null;
+  const skinFile = zip.file(root + 'skin.css');
+  if (skinFile) {
+    if (!isAdvanced) {
+      warnings.push('skin.css ignored - only Theme API v2 manifests can ship a skin');
+    } else {
+      const rawSkin = await skinFile.async('string');
+      if (rawSkin.length > MAX_THEME_SKIN_BYTES) {
+        warnings.push(`skin.css exceeds ${Math.round(MAX_THEME_SKIN_BYTES / 1024)} KB and was dropped`);
+      } else {
+        const sanitized = sanitizeSkinCSS(rawSkin);
+        skin = sanitized.css;
+        warnings.push(...sanitized.warnings);
+      }
+    }
+  }
+
   return {
     valid: errors.length === 0,
     errors,
     warnings,
     manifest,
     css: rawCSS,
+    skin,
     preview,
   };
 }

lib/security/url-guard.ts

@@ -0,0 +1,67 @@
+import { lookup } from 'node:dns/promises';
+import { BlockList, isIP } from 'node:net';
+
+const blockedAddressRanges = new BlockList();
+blockedAddressRanges.addAddress('0.0.0.0');
+blockedAddressRanges.addAddress('127.0.0.1');
+blockedAddressRanges.addSubnet('10.0.0.0', 8);
+blockedAddressRanges.addSubnet('172.16.0.0', 12);
+blockedAddressRanges.addSubnet('192.168.0.0', 16);
+blockedAddressRanges.addSubnet('169.254.0.0', 16);
+blockedAddressRanges.addAddress('::', 'ipv6');
+blockedAddressRanges.addAddress('::1', 'ipv6');
+blockedAddressRanges.addSubnet('fc00::', 7, 'ipv6');
+blockedAddressRanges.addSubnet('fe80::', 10, 'ipv6');
+
+const BLOCKED_HOSTNAMES = new Set(['localhost']);
+const BLOCKED_HOSTNAME_SUFFIXES = ['.localhost', '.local', '.internal', '.arpa', '.localdomain'];
+
+function normalizeHostname(hostname: string): string {
+  return hostname.replace(/^\[(.*)\]$/, '$1').toLowerCase();
+}
+
+function isBlockedIpAddress(hostname: string): boolean {
+  const normalized = normalizeHostname(hostname);
+  const family = isIP(normalized);
+  if (family === 4) return blockedAddressRanges.check(normalized, 'ipv4');
+  if (family === 6) return blockedAddressRanges.check(normalized, 'ipv6');
+  return false;
+}
+
+/**
+ * Returns true only when the URL targets a public host reachable over http(s).
+ * Rejects loopback / RFC-1918 / link-local / ULA addresses, special hostname
+ * suffixes (.local, .internal, .arpa, ...), URLs with embedded credentials,
+ * and any hostname whose DNS resolves to a blocked address.
+ *
+ * Note: there is a TOCTOU window between this lookup and the eventual fetch().
+ * Callers that need rebinding-safe behavior must additionally pin the resolved
+ * IP at connect time (e.g. via a custom undici dispatcher).
+ */
+export async function isPublicHttpUrl(urlString: string): Promise<boolean> {
+  let url: URL;
+  try {
+    url = new URL(urlString);
+  } catch {
+    return false;
+  }
+
+  if (url.protocol !== 'http:' && url.protocol !== 'https:') return false;
+  if (url.username || url.password) return false;
+
+  const hostname = normalizeHostname(url.hostname);
+  if (!hostname) return false;
+  if (BLOCKED_HOSTNAMES.has(hostname)) return false;
+  if (BLOCKED_HOSTNAME_SUFFIXES.some((suffix) => hostname.endsWith(suffix))) return false;
+
+  if (isBlockedIpAddress(hostname)) return false;
+  if (isIP(hostname)) return true;
+
+  try {
+    const records = await lookup(hostname, { all: true, verbatim: true });
+    if (records.length === 0) return false;
+    return records.every((record) => !isBlockedIpAddress(record.address));
+  } catch {
+    return false;
+  }
+}

lib/sub-addressing.ts

@@ -1,12 +1,32 @@
 /**
- * Sub-addressing utilities for user+tag@domain.com format
+ * Sub-addressing utilities for user{delimiter}tag@domain.com format
  * Works server-side automatically - no JMAP API calls needed
+ *
+ * The delimiter character is configurable per server (RFC 5233). Common
+ * choices: "+" (Postfix, Stalwart default), "-" (qmail), ".", "=".
  */
 
 // Constants for tag validation
 const MAX_TAG_LENGTH = 30;
 const TAG_REGEX = /^[a-zA-Z0-9-]{1,30}$/;
 
+export const DEFAULT_SUB_ADDRESS_DELIMITER = '+';
+export const SUPPORTED_SUB_ADDRESS_DELIMITERS = ['+', '-', '.', '='] as const;
+export type SubAddressDelimiterPreset = (typeof SUPPORTED_SUB_ADDRESS_DELIMITERS)[number];
+
+export function isSupportedSubAddressDelimiter(value: string): value is SubAddressDelimiterPreset {
+  return (SUPPORTED_SUB_ADDRESS_DELIMITERS as readonly string[]).includes(value);
+}
+
+// RFC 5321 atext "special" characters, minus alphanumerics and "@". A custom
+// delimiter must be exactly one of these — they're safe to embed in a local
+// part and unambiguously separate the user from the tag.
+const VALID_DELIMITER_REGEX = /^[!#$%&'*+\-./=?^_`{|}~]$/;
+
+export function isValidSubAddressDelimiter(value: unknown): value is string {
+  return typeof value === 'string' && VALID_DELIMITER_REGEX.test(value);
+}
+
 export type TagValidationErrorCode =
   | 'EMPTY'
   | 'TOO_LONG'
@@ -22,10 +42,14 @@ export interface ParsedAddress {
 }
 
 /**
- * Parse an email address to extract sub-address tag
- * Example: "user+shopping@example.com" -> { baseUser: "user", tag: "shopping" }
+ * Parse an email address to extract sub-address tag.
+ * The first occurrence of the delimiter in the local part separates the
+ * base user from the tag, matching the behavior of Postfix/qmail/Sieve.
  */
-export function parseSubAddress(email: string): ParsedAddress {
+export function parseSubAddress(
+  email: string,
+  delimiter: string = DEFAULT_SUB_ADDRESS_DELIMITER,
+): ParsedAddress {
   const [localPart, domain] = email.split('@');
 
   if (!localPart || !domain) {
@@ -38,9 +62,9 @@ export function parseSubAddress(email: string): ParsedAddress {
     };
   }
 
-  const plusIndex = localPart.indexOf('+');
+  const delimiterIndex = localPart.indexOf(delimiter);
 
-  if (plusIndex === -1) {
+  if (delimiterIndex === -1) {
     return {
       localPart,
       baseUser: localPart,
@@ -50,8 +74,8 @@ export function parseSubAddress(email: string): ParsedAddress {
     };
   }
 
-  const baseUser = localPart.substring(0, plusIndex);
-  const tag = localPart.substring(plusIndex + 1);
+  const baseUser = localPart.substring(0, delimiterIndex);
+  const tag = localPart.substring(delimiterIndex + delimiter.length);
 
   return {
     localPart,
@@ -63,18 +87,25 @@ export function parseSubAddress(email: string): ParsedAddress {
 }
 
 /**
- * Generate a sub-addressed email
- * Example: generateSubAddress("user@example.com", "shopping") -> "user+shopping@example.com"
+ * Generate a sub-addressed email.
+ * Example: generateSubAddress("user@example.com", "shopping", "+") -> "user+shopping@example.com"
  */
-export function generateSubAddress(baseEmail: string, tag: string): string {
+export function generateSubAddress(
+  baseEmail: string,
+  tag: string,
+  delimiter: string = DEFAULT_SUB_ADDRESS_DELIMITER,
+): string {
   const [localPart, domain] = baseEmail.split('@');
 
   if (!localPart || !domain || !tag) {
     return baseEmail;
   }
 
-  // Remove existing tag if present
-  const cleanLocal = localPart.split('+')[0];
+  // Strip an existing tag if one is already present
+  const existingDelimiterIndex = localPart.indexOf(delimiter);
+  const cleanLocal = existingDelimiterIndex === -1
+    ? localPart
+    : localPart.substring(0, existingDelimiterIndex);
 
   // Sanitize tag (alphanumeric and dash only)
   const cleanTag = tag.replace(/[^a-zA-Z0-9-]/g, '').toLowerCase();
@@ -83,7 +114,7 @@ export function generateSubAddress(baseEmail: string, tag: string): string {
     return baseEmail;
   }
 
-  return `${cleanLocal}+${cleanTag}@${domain}`;
+  return `${cleanLocal}${delimiter}${cleanTag}@${domain}`;
 }
 
 /**

lib/telemetry/endpoint-guard.ts

@@ -0,0 +1,115 @@
+import { lookup } from 'node:dns/promises';
+import { isIP } from 'node:net';
+
+// Block telemetry endpoints from pointing at internal/loopback addresses.
+// Required because the admin UI lets an authenticated admin set an arbitrary
+// URL; without this an attacker with a session (or a hostile admin in a
+// multi-tenant deploy) could redirect heartbeats at internal hosts.
+//
+// Set BULWARK_TELEMETRY_ALLOW_PRIVATE=1 to bypass - useful only for local
+// dev where the collector is on the loopback.
+
+const PRIVATE_V4: RegExp[] = [
+  /^0\./,                                          // 0.0.0.0/8
+  /^10\./,                                         // 10.0.0.0/8
+  /^127\./,                                        // loopback
+  /^169\.254\./,                                   // link-local + cloud metadata
+  /^172\.(1[6-9]|2\d|3[0-1])\./,                   // 172.16.0.0/12
+  /^192\.168\./,                                   // 192.168.0.0/16
+  /^192\.0\.0\./,                                  // IETF reserved
+  /^198\.(1[8-9])\./,                              // benchmarking 198.18.0.0/15
+  /^100\.(6[4-9]|[7-9]\d|1[01]\d|12[0-7])\./,      // 100.64.0.0/10 CGNAT
+  /^22[4-9]\./,                                    // 224.0.0.0/4 multicast
+  /^23\d\./,
+  /^2[4-5]\d\./,                                   // 240.0.0.0/4 reserved
+];
+
+function isPrivateV4(ip: string): boolean {
+  return PRIVATE_V4.some((re) => re.test(ip));
+}
+
+function isPrivateV6(ip: string): boolean {
+  const lower = ip.toLowerCase();
+  if (lower === '::1' || lower === '::') return true;
+  if (/^fe[89ab][0-9a-f]:/.test(lower)) return true;     // fe80::/10 link-local
+  if (/^f[cd][0-9a-f]{2}:/.test(lower)) return true;     // fc00::/7 ULA
+  const mapped = lower.match(/^::ffff:(\d+\.\d+\.\d+\.\d+)$/);
+  if (mapped) return isPrivateV4(mapped[1]);
+  return false;
+}
+
+export function isPrivateAddress(ip: string): boolean {
+  const family = isIP(ip);
+  if (family === 4) return isPrivateV4(ip);
+  if (family === 6) return isPrivateV6(ip);
+  return false;
+}
+
+const BAD_HOSTS = new Set([
+  'localhost',
+  'localhost.localdomain',
+  'ip6-localhost',
+  'ip6-loopback',
+]);
+
+function bypassEnabled(): boolean {
+  return process.env.BULWARK_TELEMETRY_ALLOW_PRIVATE === '1';
+}
+
+export type EndpointCheck = { ok: true } | { ok: false; reason: string };
+
+// Sync URL/host shape check. Catches the obvious cases without DNS.
+export function validateEndpointUrl(raw: string): EndpointCheck {
+  let url: URL;
+  try {
+    url = new URL(raw);
+  } catch {
+    return { ok: false, reason: 'invalid URL' };
+  }
+  if (url.protocol !== 'http:' && url.protocol !== 'https:') {
+    return { ok: false, reason: 'must be http(s)://' };
+  }
+  if (bypassEnabled()) return { ok: true };
+
+  const host = url.hostname.toLowerCase().replace(/^\[|\]$/g, '');
+  if (!host) return { ok: false, reason: 'host required' };
+  if (BAD_HOSTS.has(host)) {
+    return { ok: false, reason: 'localhost endpoints are not allowed' };
+  }
+  if (host.endsWith('.local') || host.endsWith('.internal') || host.endsWith('.localhost')) {
+    return { ok: false, reason: 'private TLDs are not allowed' };
+  }
+  if (isIP(host) && isPrivateAddress(host)) {
+    return { ok: false, reason: 'private/loopback IP is not allowed' };
+  }
+  return { ok: true };
+}
+
+// Async check that additionally resolves DNS hostnames. Use this on
+// set-endpoint AND immediately before fetch to defeat DNS-rebinding tricks
+// where a hostname resolves to a public IP at validation time and a private
+// one at fetch time.
+export async function resolveEndpointAllowed(raw: string): Promise<EndpointCheck> {
+  const initial = validateEndpointUrl(raw);
+  if (!initial.ok) return initial;
+  if (bypassEnabled()) return { ok: true };
+
+  const host = new URL(raw).hostname.toLowerCase().replace(/^\[|\]$/g, '');
+  if (isIP(host)) return { ok: true };
+
+  try {
+    const addrs = await lookup(host, { all: true });
+    for (const a of addrs) {
+      if (isPrivateAddress(a.address)) {
+        return { ok: false, reason: `host ${host} resolves to private address ${a.address}` };
+      }
+    }
+    return { ok: true };
+  } catch {
+    // Don't block on transient DNS failures - fetch will fail loudly anyway,
+    // and we don't want to lock admins out of their config when the resolver
+    // is flaky. The literal-IP check above already covers the direct-attack
+    // case.
+    return { ok: true };
+  }
+}

lib/telemetry/index.ts

@@ -0,0 +1,15 @@
+export { startScheduler, stopScheduler, reschedule, sendOnce } from './sender';
+export { buildPayload, markProcessStart } from './payload';
+export {
+  loadState, saveState, getInstanceId, effectiveConsent,
+} from './state';
+export { recordLogin, getLoginCounts } from './login-tracker';
+export {
+  validateEndpointUrl, resolveEndpointAllowed, isPrivateAddress,
+} from './endpoint-guard';
+export type { EndpointCheck } from './endpoint-guard';
+export type {
+  TelemetryPayload, TelemetryStateFile, ConsentState,
+  Platform, OsFamily, CountBucket, TelemetryFeatures,
+} from './types';
+export { DEFAULT_ENDPOINT } from './types';

lib/telemetry/login-tracker.ts

@@ -0,0 +1,125 @@
+import { readFile, writeFile, mkdir, rename } from 'node:fs/promises';
+import { existsSync } from 'node:fs';
+import path from 'node:path';
+import { createHmac } from 'node:crypto';
+import { logger } from '@/lib/logger';
+import { getInstanceId } from './state';
+
+// We never store usernames or server URLs in the clear. Each login is
+// recorded as HMAC-SHA256(username + '@' + serverUrl, instance_id), so the
+// file on disk cannot be cross-correlated with any other instance and is
+// not PII even if leaked.
+
+interface LoginRecord {
+  id: string;
+  lastLoginAt: string;
+}
+
+interface LoginsFile {
+  records: LoginRecord[];
+}
+
+const SEVEN_DAYS_MS = 7 * 24 * 60 * 60 * 1000;
+const RETENTION_MS = 90 * 24 * 60 * 60 * 1000;
+
+let cache: LoginsFile | null = null;
+
+function getDir(): string {
+  return process.env.TELEMETRY_DATA_DIR || path.join(process.cwd(), 'data', 'telemetry');
+}
+
+function loginsPath(): string {
+  return path.join(getDir(), 'logins.json');
+}
+
+async function ensureDir(): Promise<void> {
+  const dir = getDir();
+  if (!existsSync(dir)) await mkdir(dir, { recursive: true });
+}
+
+async function loadFile(): Promise<LoginsFile> {
+  if (cache) return cache;
+  try {
+    const raw = await readFile(loginsPath(), 'utf8');
+    const parsed = JSON.parse(raw) as Partial<LoginsFile>;
+    cache = Array.isArray(parsed?.records) ? { records: parsed.records as LoginRecord[] } : { records: [] };
+  } catch {
+    cache = { records: [] };
+  }
+  return cache;
+}
+
+async function saveFile(file: LoginsFile): Promise<void> {
+  await ensureDir();
+  cache = file;
+  const tmp = loginsPath() + '.tmp';
+  await writeFile(tmp, JSON.stringify(file), 'utf8');
+  await rename(tmp, loginsPath());
+}
+
+function normalizeServer(serverUrl: string): string {
+  return serverUrl.trim().replace(/\/+$/, '').toLowerCase();
+}
+
+async function hashIdentity(username: string, serverUrl: string): Promise<string> {
+  const instanceId = await getInstanceId();
+  const subject = `${username.trim().toLowerCase()}@${normalizeServer(serverUrl)}`;
+  return createHmac('sha256', instanceId).update(subject).digest('hex').slice(0, 32);
+}
+
+/**
+ * Record a successful login. Best-effort; never throws. Updates the
+ * existing record's timestamp if the same identity has logged in before,
+ * otherwise appends a new record. Records older than the retention window
+ * are pruned on every write.
+ */
+export async function recordLogin(username: string, serverUrl: string): Promise<void> {
+  if (!username || !serverUrl) return;
+  try {
+    const id = await hashIdentity(username, serverUrl);
+    const file = await loadFile();
+    const now = new Date().toISOString();
+    const cutoff = Date.now() - RETENTION_MS;
+    const next: LoginRecord[] = [];
+    let updated = false;
+    for (const rec of file.records) {
+      const ts = new Date(rec.lastLoginAt).getTime();
+      if (Number.isNaN(ts) || ts < cutoff) continue;
+      if (rec.id === id) {
+        next.push({ id, lastLoginAt: now });
+        updated = true;
+      } else {
+        next.push(rec);
+      }
+    }
+    if (!updated) next.push({ id, lastLoginAt: now });
+    await saveFile({ records: next });
+  } catch (err) {
+    logger.debug?.('telemetry: recordLogin failed', {
+      error: err instanceof Error ? err.message : String(err),
+    });
+  }
+}
+
+/**
+ * Total distinct accounts seen in the 90-day retention window, plus those
+ * with a login in the last 7 days.
+ */
+export async function getLoginCounts(): Promise<{ total: number; active7d: number }> {
+  try {
+    const file = await loadFile();
+    const cutoff = Date.now() - RETENTION_MS;
+    const sevenAgo = Date.now() - SEVEN_DAYS_MS;
+    let total = 0;
+    let active7d = 0;
+    for (const rec of file.records) {
+      const ts = new Date(rec.lastLoginAt).getTime();
+      if (Number.isNaN(ts) || ts < cutoff) continue;
+      total++;
+      if (ts >= sevenAgo) active7d++;
+    }
+    return { total, active7d };
+  } catch {
+    return { total: 0, active7d: 0 };
+  }
+}

lib/telemetry/payload.ts

@@ -0,0 +1,173 @@
+import { readFileSync } from 'node:fs';
+import path from 'node:path';
+import { configManager } from '@/lib/admin/config-manager';
+import { logger } from '@/lib/logger';
+import { resolveEndpointAllowed } from './endpoint-guard';
+import { getInstanceId } from './state';
+import { getLoginCounts } from './login-tracker';
+import type {
+  TelemetryPayload,
+  TelemetryFeatures,
+  Platform,
+  OsFamily,
+  CountBucket,
+} from './types';
+
+let processStartedAt = Date.now();
+export function markProcessStart(): void {
+  processStartedAt = Date.now();
+}
+
+function readPackage(): { version: string; build: string | null } {
+  try {
+    const pkg = JSON.parse(
+      readFileSync(path.join(process.cwd(), 'package.json'), 'utf8'),
+    ) as { version?: string };
+    return { version: pkg.version ?? '0.0.0', build: process.env.BULWARK_BUILD ?? 'release' };
+  } catch {
+    return { version: '0.0.0', build: null };
+  }
+}
+
+function detectPlatform(): Platform {
+  if (process.env.KUBERNETES_SERVICE_HOST) return 'k8s';
+  // /.dockerenv is the standard Docker container marker.
+  try {
+    readFileSync('/.dockerenv');
+    return 'docker';
+  } catch { /* not in docker */ }
+  return 'bare';
+}
+
+function detectOs(): OsFamily {
+  switch (process.platform) {
+    case 'linux':   return 'linux';
+    case 'darwin':  return 'darwin';
+    case 'win32':   return 'windows';
+    default:        return 'unknown';
+  }
+}
+
+export function bucketCount(n: number): CountBucket {
+  if (n <= 0) return '0';
+  if (n === 1) return '1';
+  if (n <= 5) return '2-5';
+  if (n <= 10) return '6-10';
+  if (n <= 50) return '11-50';
+  if (n <= 200) return '51-200';
+  return '201+';
+}
+
+async function readFeatures(): Promise<TelemetryFeatures> {
+  await configManager.ensureLoaded();
+  const gates = configManager.getPolicy().features;
+  const cfg = configManager.getAll();
+  return {
+    // Booleans only. We read whether a feature is enabled - never any
+    // config value beyond a presence check.
+    calendar:      gates.calendarTasksEnabled === true,
+    contacts:      gates.contactsEnabled === true,
+    files:         gates.filesEnabled === true,
+    extensions:    gates.pluginsEnabled === true,
+    oauth_enabled: cfg['oauthEnabled'] === true,
+    smime_enabled: gates.smimeEnabled === true,
+  };
+}
+
+const STALWART_VERSION_TTL_MS = 24 * 60 * 60 * 1000;
+let stalwartVersionCache: { version: string | null; fetchedAt: number } | null = null;
+
+// Stalwart returns the version in the Server response header
+// (e.g. "Stalwart Mail Server v0.16.0"). The /.well-known/jmap endpoint
+// requires auth, but the header is on the 401 response too, so an
+// unauthenticated GET is enough. Cached for a day to avoid hammering
+// the JMAP server on every payload preview.
+async function detectStalwartVersion(): Promise<string | null> {
+  if (process.env.STALWART_VERSION) return process.env.STALWART_VERSION;
+  if (stalwartVersionCache &&
+      Date.now() - stalwartVersionCache.fetchedAt < STALWART_VERSION_TTL_MS) {
+    return stalwartVersionCache.version;
+  }
+  await configManager.ensureLoaded();
+  const serverUrl = configManager.get<string>('jmapServerUrl', '').trim();
+  if (!serverUrl) {
+    stalwartVersionCache = { version: null, fetchedAt: Date.now() };
+    return null;
+  }
+  const wellKnown = `${serverUrl.replace(/\/+$/, '')}/.well-known/jmap`;
+  // Reuse the SSRF guard so a misconfigured JMAP_SERVER_URL pointing at an
+  // internal host doesn't get probed from telemetry context either.
+  const guard = await resolveEndpointAllowed(wellKnown);
+  if (!guard.ok) {
+    stalwartVersionCache = { version: null, fetchedAt: Date.now() };
+    return null;
+  }
+  try {
+    const res = await fetch(wellKnown, {
+      method: 'GET',
+      signal: AbortSignal.timeout(3000),
+    });
+    const server = res.headers.get('server') ?? '';
+    const m = server.match(/(\d+\.\d+\.\d+(?:-[\w.]+)?)/);
+    const version = m?.[1] ?? null;
+    stalwartVersionCache = { version, fetchedAt: Date.now() };
+    return version;
+  } catch (err) {
+    logger.debug?.('telemetry: stalwart version probe failed', {
+      error: err instanceof Error ? err.message : String(err),
+    });
+    stalwartVersionCache = { version: null, fetchedAt: Date.now() };
+    return null;
+  }
+}
+
+// Account counts come from the local login tracker, which records a per-
+// instance HMAC of every successful login plus the timestamp. Total = unique
+// identities seen in the last 90 days; active7d = identities with a login in
+// the last 7 days.
+
+async function countExtensions(): Promise<{ extensions: number; themes: number }> {
+  try {
+    const { getPluginRegistry, getThemeRegistry } = await import('@/lib/admin/plugin-registry');
+    const [plugins, themes] = await Promise.all([getPluginRegistry(), getThemeRegistry()]);
+    return {
+      extensions: plugins.plugins.length,
+      themes: themes.themes.length,
+    };
+  } catch {
+    return { extensions: 0, themes: 0 };
+  }
+}
+
+export async function buildPayload(): Promise<TelemetryPayload> {
+  const instance_id = await getInstanceId();
+  const { version, build } = readPackage();
+  const features = await readFeatures();
+  const accounts = await getLoginCounts();
+  const exts = await countExtensions();
+  const stalwart_version = await detectStalwartVersion();
+  const uptime_days = Math.min(
+    365,
+    Math.floor((Date.now() - processStartedAt) / 86_400_000),
+  );
+
+  return {
+    schema: '1',
+    instance_id,
+    ts: new Date().toISOString(),
+    version,
+    build,
+    platform: detectPlatform(),
+    node_version: process.versions.node,
+    os_family: detectOs(),
+    stalwart_version,
+    features,
+    counts: {
+      accounts: bucketCount(accounts.total),
+      accounts_active_7d: bucketCount(accounts.active7d),
+      extensions_installed: exts.extensions,
+      themes_installed: exts.themes,
+    },
+    uptime_days,
+  };
+}

lib/telemetry/sender.ts

@@ -0,0 +1,108 @@
+import { logger } from '@/lib/logger';
+import { effectiveConsent, endpointEnabled, loadState, saveState } from './state';
+import { buildPayload } from './payload';
+import { resolveEndpointAllowed } from './endpoint-guard';
+import { DEFAULT_ENDPOINT } from './types';
+
+const DAY_MS = 24 * 60 * 60 * 1000;
+const JITTER_MS = 2 * 60 * 60 * 1000; // ± 2 hours
+const FIRST_DELAY_MS = 60 * 60 * 1000;  // 1 hour after consent
+
+let currentTimer: NodeJS.Timeout | null = null;
+
+function jitteredDelay(base: number): number {
+  const j = (Math.random() * 2 - 1) * JITTER_MS;
+  return Math.max(60_000, base + j);
+}
+
+export async function sendOnce(opts?: { reason?: string }): Promise<{
+  ok: boolean;
+  status?: number;
+  error?: string;
+}> {
+  const { consent, source, state } = await effectiveConsent();
+  if (consent !== 'on') return { ok: false, error: `consent ${consent} (source ${source})` };
+  const endpoint = state.endpoint || DEFAULT_ENDPOINT;
+  if (!endpointEnabled(endpoint)) return { ok: false, error: 'endpoint blank' };
+
+  // Re-check at fetch time: defeats DNS rebinding, and catches the case
+  // where state.json was edited out-of-band to bypass the admin API.
+  const guard = await resolveEndpointAllowed(endpoint);
+  if (!guard.ok) {
+    logger.warn('telemetry: endpoint blocked', { reason: guard.reason });
+    return { ok: false, error: `endpoint blocked: ${guard.reason}` };
+  }
+
+  const payload = await buildPayload();
+  try {
+    const res = await fetch(endpoint, {
+      method: 'POST',
+      headers: { 'content-type': 'application/json' },
+      body: JSON.stringify(payload),
+      signal: AbortSignal.timeout(5000),
+    });
+    const ok = res.ok;
+    if (ok) {
+      const next = await loadState();
+      next.lastSentAt = new Date().toISOString();
+      await saveState(next);
+    }
+    logger.info('telemetry: heartbeat', {
+      ok, status: res.status, reason: opts?.reason ?? 'scheduled',
+    });
+    return { ok, status: res.status };
+  } catch (err) {
+    const msg = err instanceof Error ? err.message : String(err);
+    logger.warn('telemetry: heartbeat failed', { error: msg });
+    return { ok: false, error: msg };
+  }
+}
+
+async function scheduleNext(delayMs: number): Promise<void> {
+  if (currentTimer) clearTimeout(currentTimer);
+  const at = new Date(Date.now() + delayMs).toISOString();
+  const state = await loadState();
+  state.nextScheduledAt = at;
+  await saveState(state);
+  currentTimer = setTimeout(() => { void tick(); }, delayMs);
+  // Don't keep the process alive just for this.
+  currentTimer.unref?.();
+}
+
+async function tick(): Promise<void> {
+  await sendOnce({ reason: 'scheduled' });
+  await scheduleNext(jitteredDelay(DAY_MS));
+}
+
+// Called from instrumentation. Idempotent.
+export async function startScheduler(): Promise<void> {
+  const { consent } = await effectiveConsent();
+  if (consent !== 'on') {
+    logger.info('telemetry: scheduler not started', { consent });
+    return;
+  }
+  const state = await loadState();
+  // If we have a next-scheduled time in the future use it; otherwise schedule
+  // FIRST_DELAY_MS out. This means after a restart we don't fire immediately.
+  let delay = FIRST_DELAY_MS;
+  if (state.nextScheduledAt) {
+    const remaining = new Date(state.nextScheduledAt).getTime() - Date.now();
+    if (remaining > 0) delay = Math.min(remaining, DAY_MS + JITTER_MS);
+  }
+  await scheduleNext(delay);
+  logger.info('telemetry: scheduler started', {
+    nextInMs: delay,
+    endpoint: state.endpoint,
+  });
+}
+
+export async function stopScheduler(): Promise<void> {
+  if (currentTimer) clearTimeout(currentTimer);
+  currentTimer = null;
+}
+
+// Called when consent flips on/off via the UI.
+export async function reschedule(): Promise<void> {
+  await stopScheduler();
+  await startScheduler();
+}