From 534894c38db6d0f9f0fdf66b3918bac34740588f Mon Sep 17 00:00:00 2001
From: Linus Rath <139418639+rathlinus@users.noreply.github.com>
Date: Mon, 25 May 2026 16:17:32 +0200
Subject: [PATCH] feat: locale-aware date format in email list with preset
 picker #331

---
 components/settings/calendar-settings.tsx | 27 +------
 components/settings/language-settings.tsx | 89 ++++++++++++++++++++++-
 lib/utils.ts                              | 88 +++++++++++++++++++---
 locales/cs/common.json                    | 17 +++--
 locales/da/common.json                    | 17 +++--
 locales/de/common.json                    | 17 +++--
 locales/en/common.json                    | 17 +++--
 locales/es/common.json                    | 17 +++--
 locales/fr/common.json                    | 17 +++--
 locales/it/common.json                    | 17 +++--
 locales/ja/common.json                    | 17 +++--
 locales/ko/common.json                    | 17 +++--
 locales/lv/common.json                    | 17 +++--
 locales/nl/common.json                    | 17 +++--
 locales/pl/common.json                    | 17 +++--
 locales/pt/common.json                    | 17 +++--
 locales/ru/common.json                    | 17 +++--
 locales/tr/common.json                    | 17 +++--
 locales/uk/common.json                    | 17 +++--
 locales/zh/common.json                    | 17 +++--
 stores/settings-store.ts                  | 12 ++-
 21 files changed, 342 insertions(+), 163 deletions(-)

diff --git a/components/settings/calendar-settings.tsx b/components/settings/calendar-settings.tsx
index b8e655f8..4154f17b 100644
--- a/components/settings/calendar-settings.tsx
+++ b/components/settings/calendar-settings.tsx
@@ -4,17 +4,14 @@ import { useTranslations } from 'next-intl';
 import { useCalendarStore, CalendarViewMode } from '@/stores/calendar-store';
 import { useSettingsStore } from '@/stores/settings-store';
 import { usePolicyStore } from '@/stores/policy-store';
-import { SettingsSection, SettingItem, Select, RadioGroup, ToggleSwitch } from './settings-section';
+import { SettingsSection, SettingItem, Select, ToggleSwitch } from './settings-section';
 
 export function CalendarSettings() {
   const t = useTranslations('calendar.settings');
   const tViews = useTranslations('calendar.views');
-  const tDays = useTranslations('calendar.days');
 
   const { viewMode, setViewMode } = useCalendarStore();
   const {
-    timeFormat,
-    firstDayOfWeek,
     showTimeInMonthView,
     showWeekNumbers,
     enableCalendarTasks,
@@ -40,28 +37,6 @@ export function CalendarSettings() {
         />
       </SettingItem>
 
-      <SettingItem label={t('week_starts_on')}>
-        <Select
-          value={firstDayOfWeek.toString()}
-          onChange={(value) => updateSetting('firstDayOfWeek', parseInt(value) as 0 | 1)}
-          options={[
-            { value: '1', label: tDays('monday') },
-            { value: '0', label: tDays('sunday') },
-          ]}
-        />
-      </SettingItem>
-
-      <SettingItem label={t('time_format')}>
-        <RadioGroup
-          value={timeFormat}
-          onChange={(value) => updateSetting('timeFormat', value as '12h' | '24h')}
-          options={[
-            { value: '12h', label: t('time_format_12h') },
-            { value: '24h', label: t('time_format_24h') },
-          ]}
-        />
-      </SettingItem>
-
       <SettingItem
         label={t('show_time_in_month_view')}
         description={t('show_time_in_month_view_desc')}
diff --git a/components/settings/language-settings.tsx b/components/settings/language-settings.tsx
index c8e22725..1a5cdf9d 100644
--- a/components/settings/language-settings.tsx
+++ b/components/settings/language-settings.tsx
@@ -1,17 +1,100 @@
 "use client";
 
+import { useMemo } from 'react';
 import { useTranslations } from 'next-intl';
 import { LanguageSwitcher } from '@/components/ui/language-switcher';
-import { SettingsSection, SettingItem } from './settings-section';
+import { useLocaleStore } from '@/stores/locale-store';
+import { useSettingsStore } from '@/stores/settings-store';
+import type { DateFormat, TimeFormat, FirstDayOfWeek } from '@/stores/settings-store';
+import { formatDate } from '@/lib/utils';
+import { SettingsSection, SettingItem, Select, RadioGroup } from './settings-section';
 
 export function LanguageSettings() {
-  const t = useTranslations('settings.appearance');
+  const t = useTranslations('settings.language_region');
+  const tDays = useTranslations('calendar.days');
+
+  const { dateFormat, timeFormat, firstDayOfWeek, updateSetting } = useSettingsStore();
+
+  // Subscribe to locale changes so the preview re-renders on language switch
+  // (formatDate reads it via getState() and would otherwise stay stale).
+  const locale = useLocaleStore((s) => s.locale);
+
+  const preview = useMemo(() => {
+    // Build sample timestamps for each bucket so users see what their pick
+    // will look like in practice. Use offsets relative to "now" so the
+    // bucketing is stable even though the wall-clock keeps moving.
+    void locale; void dateFormat; void timeFormat;
+    const now = new Date();
+    const today = new Date(now);
+    today.setHours(15, 31, 0, 0);
+    const thisWeek = new Date(now);
+    thisWeek.setDate(now.getDate() - 2);
+    thisWeek.setHours(15, 31, 0, 0);
+    const older = new Date(now);
+    older.setMonth(now.getMonth() - 2);
+    older.setHours(15, 31, 0, 0);
+    return {
+      today: formatDate(today),
+      thisWeek: formatDate(thisWeek),
+      older: formatDate(older),
+    };
+  }, [locale, dateFormat, timeFormat]);
 
   return (
-    <SettingsSection title={t('language.label')} description={t('language.description')}>
+    <SettingsSection title={t('title')} description={t('description')}>
       <SettingItem label={t('language.label')} description={t('language.description')}>
         <LanguageSwitcher />
       </SettingItem>
+
+      <SettingItem label={t('date_format.label')} description={t('date_format.description')}>
+        <div className="flex flex-col items-end gap-2">
+          <Select
+            value={dateFormat}
+            onChange={(value) => updateSetting('dateFormat', value as DateFormat)}
+            options={[
+              { value: 'smart', label: t('date_format.smart') },
+              { value: 'relative', label: t('date_format.relative') },
+              { value: 'full', label: t('date_format.full') },
+            ]}
+          />
+          <div className="text-xs text-muted-foreground text-right space-y-0.5 font-mono">
+            <div>
+              <span className="opacity-70">{t('date_format.preview_today')} </span>
+              <span className="text-foreground/90">{preview.today}</span>
+            </div>
+            <div>
+              <span className="opacity-70">{t('date_format.preview_this_week')} </span>
+              <span className="text-foreground/90">{preview.thisWeek}</span>
+            </div>
+            <div>
+              <span className="opacity-70">{t('date_format.preview_older')} </span>
+              <span className="text-foreground/90">{preview.older}</span>
+            </div>
+          </div>
+        </div>
+      </SettingItem>
+
+      <SettingItem label={t('time_format.label')} description={t('time_format.description')}>
+        <RadioGroup
+          value={timeFormat}
+          onChange={(value) => updateSetting('timeFormat', value as TimeFormat)}
+          options={[
+            { value: '12h', label: t('time_format.12h') },
+            { value: '24h', label: t('time_format.24h') },
+          ]}
+        />
+      </SettingItem>
+
+      <SettingItem label={t('first_day.label')} description={t('first_day.description')}>
+        <Select
+          value={firstDayOfWeek.toString()}
+          onChange={(value) => updateSetting('firstDayOfWeek', parseInt(value) as FirstDayOfWeek)}
+          options={[
+            { value: '1', label: tDays('monday') },
+            { value: '0', label: tDays('sunday') },
+          ]}
+        />
+      </SettingItem>
     </SettingsSection>
   );
 }
diff --git a/lib/utils.ts b/lib/utils.ts
index d6bd9371..9c623d27 100644
--- a/lib/utils.ts
+++ b/lib/utils.ts
@@ -3,6 +3,8 @@ import { twMerge } from "tailwind-merge";
 import { Mailbox, UNIFIED_MAILBOX_IDS } from "./jmap/types";
 import type { UnifiedMailboxRole } from "./jmap/types";
 import { debug } from "./debug";
+import { useLocaleStore } from "@/stores/locale-store";
+import { useSettingsStore } from "@/stores/settings-store";
 
 export function cn(...inputs: ClassValue[]) {
   return twMerge(clsx(inputs));
@@ -40,24 +42,86 @@ export function generateUUID(): string {
   return `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(16, 20)}-${hex.slice(20)}`;
 }
 
+/**
+ * Formats a received-at date for the email list. The output style is
+ * controlled by the `dateFormat` user setting:
+ *
+ *   - `smart` (default) — locale-aware, age-bucketed:
+ *       today        → time only           ("15:31" or "3:31 PM")
+ *       last 7 days  → short weekday+time  ("Fr 15:31", "Fri 3:31 PM")
+ *       older        → full locale date    ("28.04.2026", "04/28/2026")
+ *   - `relative` — legacy en-US relative format ("1h ago", "2d ago").
+ *   - `full` — always the full locale date+time.
+ *
+ * Both the locale (from the language picker) and 12h/24h preference are
+ * read via `getState()` so this stays SSR-safe.
+ */
 export function formatDate(date: Date | string): string {
   const d = typeof date === "string" ? new Date(date) : date;
   const now = new Date();
-  const diff = now.getTime() - d.getTime();
 
-  const minutes = Math.floor(diff / 60000);
-  const hours = Math.floor(diff / 3600000);
-  const days = Math.floor(diff / 86400000);
+  const localeRaw = useLocaleStore.getState().locale;
+  const locale = localeRaw && localeRaw.length > 0 ? localeRaw : "en";
+  // `en` alone resolves to en-US in Intl; everything else uses the language
+  // subtag as-is and lets the runtime pick a sensible default region.
+  const intlLocale = locale === "en" ? "en-US" : locale;
+  const { dateFormat, timeFormat } = useSettingsStore.getState();
+  const hour12 = timeFormat === "12h";
 
-  if (minutes < 1) return "Just now";
-  if (minutes < 60) return `${minutes}m ago`;
-  if (hours < 24) return `${hours}h ago`;
-  if (days < 7) return `${days}d ago`;
+  if (dateFormat === "relative") {
+    const diff = now.getTime() - d.getTime();
+    const minutes = Math.floor(diff / 60000);
+    const hours = Math.floor(diff / 3600000);
+    const days = Math.floor(diff / 86400000);
+    if (minutes < 1) return "Just now";
+    if (minutes < 60) return `${minutes}m ago`;
+    if (hours < 24) return `${hours}h ago`;
+    if (days < 7) return `${days}d ago`;
+    return d.toLocaleDateString(intlLocale, {
+      month: "short",
+      day: "numeric",
+      year: d.getFullYear() !== now.getFullYear() ? "numeric" : undefined,
+    });
+  }
 
-  return d.toLocaleDateString("en-US", {
-    month: "short",
-    day: "numeric",
-    year: d.getFullYear() !== now.getFullYear() ? "numeric" : undefined,
+  if (dateFormat === "full") {
+    return d.toLocaleString(intlLocale, {
+      year: "numeric",
+      month: "2-digit",
+      day: "2-digit",
+      hour: "2-digit",
+      minute: "2-digit",
+      hour12,
+    });
+  }
+
+  // 'smart' (default)
+  const timeStr = d.toLocaleTimeString(intlLocale, {
+    hour: "2-digit",
+    minute: "2-digit",
+    hour12,
+  });
+
+  const isSameDay =
+    d.getFullYear() === now.getFullYear() &&
+    d.getMonth() === now.getMonth() &&
+    d.getDate() === now.getDate();
+  if (isSameDay) return timeStr;
+
+  const daysAgo = Math.floor((now.getTime() - d.getTime()) / 86400000);
+  if (daysAgo < 7) {
+    // German Intl outputs "Fr." with a trailing dot for `weekday: 'short'`;
+    // strip it so the result reads cleanly next to the time.
+    const weekday = d
+      .toLocaleDateString(intlLocale, { weekday: "short" })
+      .replace(/\.$/, "");
+    return `${weekday} ${timeStr}`;
+  }
+
+  return d.toLocaleDateString(intlLocale, {
+    year: "numeric",
+    month: "2-digit",
+    day: "2-digit",
   });
 }
 
diff --git a/locales/cs/common.json b/locales/cs/common.json
index ba4801a0..833f774a 100644
--- a/locales/cs/common.json
+++ b/locales/cs/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Pokračovat v úpravách",
     "tabs": {
       "appearance": "Vzhled",
-      "language": "Jazyk a region",
+      "language": "Jazyk, region a čas",
       "email": "Chování e-mailu",
       "composer": "Psaní zpráv",
       "privacy": "Soukromí a bezpečnost",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Jazyk a region",
-      "description": "Nakonfigurujte jazykové a místní předvolby",
+      "title": "Jazyk, region a čas",
+      "description": "Jazyk, formát data, formát času a další regionální předvolby",
       "language": {
         "label": "Jazyk",
         "description": "Vyberte preferovaný jazyk",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Formát data",
-        "description": "Jak se mají zobrazovat data",
-        "regional": "Místní",
-        "iso": "ISO 8601",
-        "custom": "Vlastní"
+        "description": "Jak se zobrazují data v seznamu e-mailů",
+        "smart": "Chytrý (regionální)",
+        "relative": "Relativní (před 1 h, před 2 d)",
+        "full": "Vždy úplné datum",
+        "preview_today": "Dnes:",
+        "preview_this_week": "Tento týden:",
+        "preview_older": "Starší:"
       },
       "time_format": {
         "label": "Formát času",
diff --git a/locales/da/common.json b/locales/da/common.json
index 12e51df1..ba1aba8a 100644
--- a/locales/da/common.json
+++ b/locales/da/common.json
@@ -755,7 +755,7 @@
     "search_no_results": "Ingen match i indstillinger",
     "tabs": {
       "appearance": "Udseende",
-      "language": "Sprog & region",
+      "language": "Sprog, region & tid",
       "email": "E-mail-adfærd",
       "composer": "Komponist",
       "privacy": "Privatliv & sikkerhed",
@@ -935,8 +935,8 @@
       }
     },
     "language_region": {
-      "title": "Sprog & region",
-      "description": "Konfigurér sprog og regionale præferencer",
+      "title": "Sprog, region & tid",
+      "description": "Sprog, datoformat, tidsformat og andre regionale indstillinger",
       "language": {
         "label": "Sprog",
         "description": "Vælg dit foretrukne sprog",
@@ -945,10 +945,13 @@
       },
       "date_format": {
         "label": "Datoformat",
-        "description": "Hvordan datoer skal vises",
-        "regional": "Regionalt",
-        "iso": "ISO 8601",
-        "custom": "Brugerdefineret"
+        "description": "Sådan vises datoer på e-mail-listen",
+        "smart": "Smart (regionalt)",
+        "relative": "Relativ (for 1 t siden, for 2 d siden)",
+        "full": "Altid fuld dato",
+        "preview_today": "I dag:",
+        "preview_this_week": "Denne uge:",
+        "preview_older": "Ældre:"
       },
       "time_format": {
         "label": "Tidsformat",
diff --git a/locales/de/common.json b/locales/de/common.json
index e834e9a7..eb9a913f 100644
--- a/locales/de/common.json
+++ b/locales/de/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Weiter bearbeiten",
     "tabs": {
       "appearance": "Darstellung",
-      "language": "Sprache & Region",
+      "language": "Sprache, Region & Zeit",
       "email": "E-Mail-Verhalten",
       "composer": "Editor",
       "privacy": "Datenschutz & Sicherheit",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Sprache & Region",
-      "description": "Konfigurieren Sie Sprach- und Regionaleinstellungen",
+      "title": "Sprache, Region & Zeit",
+      "description": "Sprache, Datums- und Zeitformat sowie weitere regionale Einstellungen",
       "language": {
         "label": "Sprache",
         "description": "Wählen Sie Ihre bevorzugte Sprache",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Datumsformat",
-        "description": "Wie Daten angezeigt werden sollen",
-        "regional": "Regional",
-        "iso": "ISO 8601",
-        "custom": "Benutzerdefiniert"
+        "description": "Wie Daten in der E-Mail-Liste angezeigt werden",
+        "smart": "Intelligent (gebietsschemaabhängig)",
+        "relative": "Relativ (vor 1 Std., vor 2 Tagen)",
+        "full": "Immer vollständiges Datum",
+        "preview_today": "Heute:",
+        "preview_this_week": "Diese Woche:",
+        "preview_older": "Älter:"
       },
       "time_format": {
         "label": "Zeitformat",
diff --git a/locales/en/common.json b/locales/en/common.json
index d916c100..072169df 100644
--- a/locales/en/common.json
+++ b/locales/en/common.json
@@ -755,7 +755,7 @@
     "search_no_results": "No matching settings",
     "tabs": {
       "appearance": "Appearance",
-      "language": "Language & Region",
+      "language": "Language, Region & Time",
       "email": "Email Behavior",
       "composer": "Composer",
       "privacy": "Privacy & Security",
@@ -935,8 +935,8 @@
       }
     },
     "language_region": {
-      "title": "Language & Region",
-      "description": "Configure language and regional preferences",
+      "title": "Language, Region & Time",
+      "description": "Language, date format, time format, and other regional preferences",
       "language": {
         "label": "Language",
         "description": "Choose your preferred language",
@@ -945,10 +945,13 @@
       },
       "date_format": {
         "label": "Date Format",
-        "description": "How dates should be displayed",
-        "regional": "Regional",
-        "iso": "ISO 8601",
-        "custom": "Custom"
+        "description": "How dates are shown in the email list",
+        "smart": "Smart (locale-aware)",
+        "relative": "Relative (1h ago, 2d ago)",
+        "full": "Always full date",
+        "preview_today": "Today:",
+        "preview_this_week": "This week:",
+        "preview_older": "Older:"
       },
       "time_format": {
         "label": "Time Format",
diff --git a/locales/es/common.json b/locales/es/common.json
index 950a5e37..60687c16 100644
--- a/locales/es/common.json
+++ b/locales/es/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Seguir editando",
     "tabs": {
       "appearance": "Apariencia",
-      "language": "Idioma y Región",
+      "language": "Idioma, Región y Hora",
       "email": "Comportamiento del Correo",
       "composer": "Editor",
       "privacy": "Privacidad y Seguridad",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Idioma y Región",
-      "description": "Configure las preferencias de idioma y región",
+      "title": "Idioma, Región y Hora",
+      "description": "Idioma, formato de fecha, formato de hora y otras preferencias regionales",
       "language": {
         "label": "Idioma",
         "description": "Elija su idioma preferido",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Formato de Fecha",
-        "description": "Cómo se deben mostrar las fechas",
-        "regional": "Regional",
-        "iso": "ISO 8601",
-        "custom": "Personalizado"
+        "description": "Cómo se muestran las fechas en la lista de correos",
+        "smart": "Inteligente (según región)",
+        "relative": "Relativo (hace 1 h, hace 2 d)",
+        "full": "Fecha completa siempre",
+        "preview_today": "Hoy:",
+        "preview_this_week": "Esta semana:",
+        "preview_older": "Más antiguo:"
       },
       "time_format": {
         "label": "Formato de Hora",
diff --git a/locales/fr/common.json b/locales/fr/common.json
index f3c7067d..41ca1cf0 100644
--- a/locales/fr/common.json
+++ b/locales/fr/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Continuer l'édition",
     "tabs": {
       "appearance": "Apparence",
-      "language": "Langue et région",
+      "language": "Langue, région et heure",
       "email": "Comportement email",
       "composer": "Compositeur",
       "privacy": "Confidentialité et sécurité",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Langue et région",
-      "description": "Configurez vos préférences linguistiques et régionales",
+      "title": "Langue, région et heure",
+      "description": "Langue, format de date, format d'heure et autres préférences régionales",
       "language": {
         "label": "Langue",
         "description": "Choisissez votre langue préférée",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Format de date",
-        "description": "Comment les dates doivent être affichées",
-        "regional": "Régional",
-        "iso": "ISO 8601",
-        "custom": "Personnalisé"
+        "description": "Comment les dates apparaissent dans la liste des e-mails",
+        "smart": "Intelligent (adapté à la région)",
+        "relative": "Relatif (il y a 1 h, il y a 2 j)",
+        "full": "Toujours la date complète",
+        "preview_today": "Aujourd'hui :",
+        "preview_this_week": "Cette semaine :",
+        "preview_older": "Plus ancien :"
       },
       "time_format": {
         "label": "Format d'heure",
diff --git a/locales/it/common.json b/locales/it/common.json
index 7723fe38..e7a0d7e5 100644
--- a/locales/it/common.json
+++ b/locales/it/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Continua a modificare",
     "tabs": {
       "appearance": "Aspetto",
-      "language": "Lingua e regione",
+      "language": "Lingua, regione e ora",
       "email": "Comportamento email",
       "composer": "Editor",
       "privacy": "Privacy e sicurezza",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Lingua e regione",
-      "description": "Configura le preferenze di lingua e regionali",
+      "title": "Lingua, regione e ora",
+      "description": "Lingua, formato data, formato ora e altre preferenze regionali",
       "language": {
         "label": "Lingua",
         "description": "Scegli la tua lingua preferita",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Formato data",
-        "description": "Come devono essere visualizzate le date",
-        "regional": "Regionale",
-        "iso": "ISO 8601",
-        "custom": "Personalizzato"
+        "description": "Come vengono visualizzate le date nell'elenco delle e-mail",
+        "smart": "Intelligente (in base alla regione)",
+        "relative": "Relativo (1 h fa, 2 g fa)",
+        "full": "Sempre data completa",
+        "preview_today": "Oggi:",
+        "preview_this_week": "Questa settimana:",
+        "preview_older": "Più vecchio:"
       },
       "time_format": {
         "label": "Formato ora",
diff --git a/locales/ja/common.json b/locales/ja/common.json
index 8f37e703..85ecd13b 100644
--- a/locales/ja/common.json
+++ b/locales/ja/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "編集を続ける",
     "tabs": {
       "appearance": "外観",
-      "language": "言語と地域",
+      "language": "言語、地域、時刻",
       "email": "メール動作",
       "composer": "作成",
       "privacy": "プライバシーとセキュリティ",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "言語と地域",
-      "description": "言語と地域の設定を構成",
+      "title": "言語、地域、時刻",
+      "description": "言語、日付形式、時刻形式、その他の地域設定",
       "language": {
         "label": "言語",
         "description": "お好みの言語を選択",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "日付形式",
-        "description": "日付の表示形式",
-        "regional": "地域設定",
-        "iso": "ISO 8601",
-        "custom": "カスタム"
+        "description": "メール一覧での日付の表示方法",
+        "smart": "スマート（地域に合わせる）",
+        "relative": "相対表示（1時間前、2日前）",
+        "full": "常に完全な日付",
+        "preview_today": "今日:",
+        "preview_this_week": "今週:",
+        "preview_older": "それ以前:"
       },
       "time_format": {
         "label": "時刻形式",
diff --git a/locales/ko/common.json b/locales/ko/common.json
index 722fbf06..5b34dd9a 100644
--- a/locales/ko/common.json
+++ b/locales/ko/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "계속 수정하기",
     "tabs": {
       "appearance": "화면 설정",
-      "language": "언어 및 지역",
+      "language": "언어, 지역 및 시간",
       "email": "메일 동작",
       "composer": "메일 쓰기",
       "privacy": "개인정보 및 보안",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "언어 및 지역",
-      "description": "언어와 지역 형식을 설정해 주세요",
+      "title": "언어, 지역 및 시간",
+      "description": "언어, 날짜 형식, 시간 형식 및 기타 지역 환경설정",
       "language": {
         "label": "언어",
         "description": "사용할 언어를 선택해 주세요",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "날짜 형식",
-        "description": "날짜가 표시되는 방식을 설정해요",
-        "regional": "지역 설정",
-        "iso": "ISO 8601",
-        "custom": "사용자 지정"
+        "description": "이메일 목록에 날짜가 표시되는 방식",
+        "smart": "스마트 (지역에 맞춤)",
+        "relative": "상대 시간 (1시간 전, 2일 전)",
+        "full": "항상 전체 날짜",
+        "preview_today": "오늘:",
+        "preview_this_week": "이번 주:",
+        "preview_older": "이전:"
       },
       "time_format": {
         "label": "시간 형식",
diff --git a/locales/lv/common.json b/locales/lv/common.json
index 7c4311a2..eb405b2f 100644
--- a/locales/lv/common.json
+++ b/locales/lv/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Turpināt rediģēšanu",
     "tabs": {
       "appearance": "Izskats",
-      "language": "Valoda un reģions",
+      "language": "Valoda, reģions un laiks",
       "email": "Pasta darbība",
       "composer": "Redaktors",
       "privacy": "Privātums un drošība",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Valoda un reģions",
-      "description": "Iestatiet valodas un reģionālās preferences",
+      "title": "Valoda, reģions un laiks",
+      "description": "Valoda, datuma formāts, laika formāts un citas reģionālās preferences",
       "language": {
         "label": "Valoda",
         "description": "Izvēlieties vēlamo valodu",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Datuma formāts",
-        "description": "Kā attēlot datumus",
-        "regional": "Reģionālais",
-        "iso": "ISO 8601",
-        "custom": "Pielāgots"
+        "description": "Kā datumi tiek attēloti e-pasta sarakstā",
+        "smart": "Gudrs (atbilstoši reģionam)",
+        "relative": "Relatīvs (pirms 1 st., pirms 2 d.)",
+        "full": "Vienmēr pilns datums",
+        "preview_today": "Šodien:",
+        "preview_this_week": "Šajā nedēļā:",
+        "preview_older": "Vecāks:"
       },
       "time_format": {
         "label": "Laika formāts",
diff --git a/locales/nl/common.json b/locales/nl/common.json
index ea6ad7db..65397108 100644
--- a/locales/nl/common.json
+++ b/locales/nl/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Doorgaan met bewerken",
     "tabs": {
       "appearance": "Uiterlijk",
-      "language": "Taal & Regio",
+      "language": "Taal, Regio & Tijd",
       "email": "E-mailgedrag",
       "composer": "Opstellen",
       "privacy": "Privacy & Beveiliging",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Taal & Regio",
-      "description": "Configureer taal- en regiovoorkeuren",
+      "title": "Taal, Regio & Tijd",
+      "description": "Taal, datumnotatie, tijdnotatie en andere regionale voorkeuren",
       "language": {
         "label": "Taal",
         "description": "Kies je voorkeurstaal",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Datumnotatie",
-        "description": "Hoe datums moeten worden weergegeven",
-        "regional": "Regionaal",
-        "iso": "ISO 8601",
-        "custom": "Aangepast"
+        "description": "Hoe datums worden weergegeven in de e-maillijst",
+        "smart": "Slim (regionaal)",
+        "relative": "Relatief (1 u geleden, 2 d geleden)",
+        "full": "Altijd volledige datum",
+        "preview_today": "Vandaag:",
+        "preview_this_week": "Deze week:",
+        "preview_older": "Ouder:"
       },
       "time_format": {
         "label": "Tijdnotatie",
diff --git a/locales/pl/common.json b/locales/pl/common.json
index 2ff0dc34..151c4a06 100644
--- a/locales/pl/common.json
+++ b/locales/pl/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Kontynuuj edycję",
     "tabs": {
       "appearance": "Wygląd",
-      "language": "Język i region",
+      "language": "Język, region i czas",
       "email": "Zachowanie poczty e-mail",
       "composer": "Redagowanie",
       "privacy": "Prywatność i bezpieczeństwo",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Język i region",
-      "description": "Skonfiguruj preferencje językowe i regionalne",
+      "title": "Język, region i czas",
+      "description": "Język, format daty, format godziny i inne preferencje regionalne",
       "language": {
         "label": "Język",
         "description": "Wybierz preferowany język",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Format daty",
-        "description": "Jak mają być wyświetlane daty",
-        "regional": "Regionalny",
-        "iso": "ISO 8601",
-        "custom": "Niestandardowy"
+        "description": "Jak daty są wyświetlane na liście e-maili",
+        "smart": "Inteligentny (regionalny)",
+        "relative": "Względny (1 g temu, 2 d temu)",
+        "full": "Zawsze pełna data",
+        "preview_today": "Dzisiaj:",
+        "preview_this_week": "W tym tygodniu:",
+        "preview_older": "Starsze:"
       },
       "time_format": {
         "label": "Format czasu",
diff --git a/locales/pt/common.json b/locales/pt/common.json
index 489605fe..a6ce3596 100644
--- a/locales/pt/common.json
+++ b/locales/pt/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Continuar editando",
     "tabs": {
       "appearance": "Aparência",
-      "language": "Idioma e Região",
+      "language": "Idioma, Região e Hora",
       "email": "Comportamento de E-mail",
       "composer": "Editor",
       "privacy": "Privacidade e Segurança",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Idioma e Região",
-      "description": "Configure preferências de idioma e região",
+      "title": "Idioma, Região e Hora",
+      "description": "Idioma, formato de data, formato de hora e outras preferências regionais",
       "language": {
         "label": "Idioma",
         "description": "Escolha seu idioma preferido",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Formato de Data",
-        "description": "Como as datas devem ser exibidas",
-        "regional": "Regional",
-        "iso": "ISO 8601",
-        "custom": "Personalizado"
+        "description": "Como as datas são mostradas na lista de e-mails",
+        "smart": "Inteligente (regional)",
+        "relative": "Relativo (há 1 h, há 2 d)",
+        "full": "Sempre data completa",
+        "preview_today": "Hoje:",
+        "preview_this_week": "Esta semana:",
+        "preview_older": "Mais antigo:"
       },
       "time_format": {
         "label": "Formato de Hora",
diff --git a/locales/ru/common.json b/locales/ru/common.json
index da8e624b..45e2de45 100644
--- a/locales/ru/common.json
+++ b/locales/ru/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Продолжить редактирование",
     "tabs": {
       "appearance": "Внешний вид",
-      "language": "Язык и регион",
+      "language": "Язык, регион и время",
       "email": "Поведение почты",
       "composer": "Редактор",
       "privacy": "Конфиденциальность и безопасность",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Язык и регион",
-      "description": "Настройте языковые и региональные предпочтения",
+      "title": "Язык, регион и время",
+      "description": "Язык, формат даты, формат времени и другие региональные настройки",
       "language": {
         "label": "Язык",
         "description": "Выберите предпочтительный язык",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Формат даты",
-        "description": "Как отображать даты",
-        "regional": "Региональный",
-        "iso": "ISO 8601",
-        "custom": "Пользовательский"
+        "description": "Как отображаются даты в списке писем",
+        "smart": "Умный (по региону)",
+        "relative": "Относительный (1 ч назад, 2 д назад)",
+        "full": "Всегда полная дата",
+        "preview_today": "Сегодня:",
+        "preview_this_week": "На этой неделе:",
+        "preview_older": "Старее:"
       },
       "time_format": {
         "label": "Формат времени",
diff --git a/locales/tr/common.json b/locales/tr/common.json
index c9e6648a..7d2f5037 100644
--- a/locales/tr/common.json
+++ b/locales/tr/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Düzenlemeye devam et",
     "tabs": {
       "appearance": "Görünüm",
-      "language": "Dil ve Bölge",
+      "language": "Dil, Bölge ve Saat",
       "email": "E-posta Davranışı",
       "composer": "Yazıcı",
       "privacy": "Gizlilik ve Güvenlik",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Dil ve Bölge",
-      "description": "Dil ve bölgesel tercihleri yapılandırın",
+      "title": "Dil, Bölge ve Saat",
+      "description": "Dil, tarih biçimi, saat biçimi ve diğer bölgesel tercihler",
       "language": {
         "label": "Dil",
         "description": "Tercih ettiğiniz dili seçin",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Tarih Biçimi",
-        "description": "Tarihlerin nasıl görüntüleneceği",
-        "regional": "Bölgesel",
-        "iso": "ISO 8601",
-        "custom": "Özel"
+        "description": "Tarihlerin e-posta listesinde nasıl gösterileceği",
+        "smart": "Akıllı (bölgeye duyarlı)",
+        "relative": "Göreceli (1 sa önce, 2 g önce)",
+        "full": "Her zaman tam tarih",
+        "preview_today": "Bugün:",
+        "preview_this_week": "Bu hafta:",
+        "preview_older": "Daha eski:"
       },
       "time_format": {
         "label": "Saat Biçimi",
diff --git a/locales/uk/common.json b/locales/uk/common.json
index 54bc2ec1..fd1a458d 100644
--- a/locales/uk/common.json
+++ b/locales/uk/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "Продовжуйте редагувати",
     "tabs": {
       "appearance": "Зовнішній вигляд",
-      "language": "Мова та регіон",
+      "language": "Мова, регіон і час",
       "email": "Поведінка електронної пошти",
       "composer": "Композитор",
       "privacy": "Конфіденційність і безпека",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "Мова та регіон",
-      "description": "Налаштуйте мовні та регіональні параметри",
+      "title": "Мова, регіон і час",
+      "description": "Мова, формат дати, формат часу та інші регіональні налаштування",
       "language": {
         "label": "Мова",
         "description": "Виберіть бажану мову",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "Формат дати",
-        "description": "Як мають відображатися дати",
-        "regional": "Регіональний",
-        "iso": "ISO 8601",
-        "custom": "Довільний"
+        "description": "Як відображаються дати у списку листів",
+        "smart": "Розумний (за регіоном)",
+        "relative": "Відносний (1 год тому, 2 дн тому)",
+        "full": "Завжди повна дата",
+        "preview_today": "Сьогодні:",
+        "preview_this_week": "Цього тижня:",
+        "preview_older": "Старіше:"
       },
       "time_format": {
         "label": "Формат часу",
diff --git a/locales/zh/common.json b/locales/zh/common.json
index 2be4f21e..3de1074e 100644
--- a/locales/zh/common.json
+++ b/locales/zh/common.json
@@ -752,7 +752,7 @@
     "keep_editing": "继续编辑",
     "tabs": {
       "appearance": "外观",
-      "language": "语言及地区",
+      "language": "语言、地区与时间",
       "email": "邮件行为",
       "composer": "邮件撰写",
       "privacy": "隐私与安全",
@@ -932,8 +932,8 @@
       }
     },
     "language_region": {
-      "title": "语言及地区",
-      "description": "配置语言和区域首选项",
+      "title": "语言、地区与时间",
+      "description": "语言、日期格式、时间格式以及其他区域设置",
       "language": {
         "label": "语言",
         "description": "选择您的首选语言",
@@ -942,10 +942,13 @@
       },
       "date_format": {
         "label": "日期格式",
-        "description": "日期应如何显示",
-        "regional": "区域格式",
-        "iso": "ISO 8601",
-        "custom": "自定义"
+        "description": "电子邮件列表中日期的显示方式",
+        "smart": "智能（按地区）",
+        "relative": "相对时间（1 小时前、2 天前）",
+        "full": "始终完整日期",
+        "preview_today": "今天：",
+        "preview_this_week": "本周：",
+        "preview_older": "更早："
       },
       "time_format": {
         "label": "时间格式",
diff --git a/stores/settings-store.ts b/stores/settings-store.ts
index a93ab891..08bc4a05 100644
--- a/stores/settings-store.ts
+++ b/stores/settings-store.ts
@@ -31,7 +31,7 @@ export type ListDensity = Density;
 export type DeleteAction = 'trash' | 'trash-and-read' | 'permanent';
 export type ReplyMode = 'reply' | 'replyAll';
 export type SignaturePosition = 'above_quote' | 'below_quote';
-export type DateFormat = 'regional' | 'iso' | 'custom';
+export type DateFormat = 'smart' | 'relative' | 'full';
 export type TimeFormat = '12h' | '24h';
 export type FirstDayOfWeek = 0 | 1; // 0 = Sunday, 1 = Monday
 export type ExternalContentPolicy = 'ask' | 'block' | 'allow';
@@ -300,7 +300,7 @@ const DEFAULT_SETTINGS = {
   animationsEnabled: true,
 
   // Language & Region
-  dateFormat: 'regional' as DateFormat,
+  dateFormat: 'smart' as DateFormat,
   timeFormat: '24h' as TimeFormat,
   firstDayOfWeek: 1 as FirstDayOfWeek, // Monday
 
@@ -760,7 +760,7 @@ export const useSettingsStore = create<SettingsState>()(
     }),
     {
       name: 'settings-storage',
-      version: 3,
+      version: 4,
       migrate: (persisted, version) => {
         const state = persisted as Record<string, unknown>;
         if (version < 2 && state.listDensity) {
@@ -771,6 +771,12 @@ export const useSettingsStore = create<SettingsState>()(
           state.protocolOpenMode = state.protocolMailtoOpenMode;
         }
         delete state.protocolMailtoOpenMode;
+        // v4: `dateFormat` was repurposed from 'regional'|'iso'|'custom' to
+        // 'smart'|'relative'|'full'. The old setting was never read anywhere,
+        // so every persisted value maps to the new default.
+        if (version < 4) {
+          state.dateFormat = 'smart';
+        }
         return state as unknown as SettingsState;
       },
       onRehydrateStorage: () => {