feat: add mail layout settings and update email list components

app/[locale]/page.tsx

@@ -53,6 +53,7 @@ export default function Home() {
   const t = useTranslations();
   const tCommon = useTranslations('common');
   const { appName } = useConfig();
+  const mailLayout = useSettingsStore((state) => state.mailLayout);
   const [showComposer, setShowComposer] = useState(false);
   const [composerMode, setComposerMode] = useState<'compose' | 'reply' | 'replyAll' | 'forward'>('compose');
   const [composerDraftText, setComposerDraftText] = useState("");
@@ -970,6 +971,10 @@ export default function Home() {
 
   // Get current mailbox name for mobile header
   const currentMailboxName = mailboxes.find(m => m.id === selectedMailbox)?.name || "Inbox";
+  const isFocusedMailLayout = mailLayout === 'focus';
+  const hasViewerContent = showComposer || Boolean(conversationThread) || Boolean(selectedEmail);
+  const shouldCollapseListPane = (isTablet && !tabletListVisible) || (!isMobile && isFocusedMailLayout && hasViewerContent);
+  const shouldHideViewerPane = !isMobile && isFocusedMailLayout && !hasViewerContent;
 
   // Handle email selection with mobile view switching
   const handleEmailSelect = async (email: { id: string }) => {
@@ -1020,6 +1025,9 @@ export default function Home() {
       setConversationEmails([]);
     }
     selectEmail(null);
+    if (isTablet) {
+      setTabletListVisible(true);
+    }
     setActiveView("list");
   };
 
@@ -1202,10 +1210,9 @@ export default function Home() {
               // Tablet/Desktop: fixed width with collapse animation
               "md:flex-shrink-0 md:shadow-sm",
               !isResizing && "transition-all duration-200 ease-out",
-              // Tablet: collapse when email selected
+              shouldCollapseListPane && "md:w-0 md:opacity-0 md:overflow-hidden md:border-r-0"
-              isTablet && !tabletListVisible && "md:w-0 md:opacity-0 md:overflow-hidden md:border-r-0"
             )}
-            style={!isMobile && !(isTablet && !tabletListVisible) ? { width: emailListWidth } : undefined}
+            style={!isMobile && !shouldCollapseListPane ? { width: emailListWidth } : undefined}
           >
             {/* Mobile Header for List View */}
             <MobileHeader
@@ -1507,7 +1514,7 @@ export default function Home() {
           </div>
 
           {/* Email list resize handle (desktop only) */}
-          {!isMobile && !isTablet && (
+          {!isMobile && !isTablet && !isFocusedMailLayout && (
             <ResizeHandle
               onResizeStart={() => { dragStartWidth.current = emailListWidth; setIsResizing(true); }}
               onResize={(delta) => setEmailListWidth(dragStartWidth.current + delta)}
@@ -1524,7 +1531,8 @@ export default function Home() {
               "max-md:fixed max-md:inset-0 max-md:z-30",
               isMobile && activeView !== "viewer" && "max-md:hidden",
               // Tablet/Desktop: relative
-              "md:relative"
+              "md:relative",
+              shouldHideViewerPane && "md:hidden"
             )}
           >
             {/* Inline Composer - shown in viewer pane */}
@@ -1652,10 +1660,7 @@ export default function Home() {
                     }}
                     onDownloadAttachment={handleDownloadAttachment}
                     onQuickReply={handleQuickReply}
-                    onBack={() => {
+                    onBack={handleMobileBack}
-                      setTabletListVisible(true);
-                      selectEmail(null);
-                    }}
                     onNavigateNext={handleNavigateNext}
                     onNavigatePrev={handleNavigatePrev}
                     onShowShortcuts={() => setShowShortcutsModal(true)}

app/admin/policy/page.tsx

@@ -28,6 +28,7 @@ const RESTRICTABLE_SETTINGS = [
   { key: 'markAsReadDelay', label: 'Mark as Read Delay', category: 'Email', type: 'number' },
   { key: 'deleteAction', label: 'Delete Action', category: 'Email', type: 'enum', allowedValues: ['trash', 'permanent'] },
   { key: 'showPreview', label: 'Show Preview', category: 'Email', type: 'boolean' },
+  { key: 'mailLayout', label: 'Mail Layout', category: 'Email', type: 'enum', allowedValues: ['split', 'focus'] },
   { key: 'emailsPerPage', label: 'Emails Per Page', category: 'Email', type: 'number' },
   { key: 'externalContentPolicy', label: 'External Content Policy', category: 'Email', type: 'enum', allowedValues: ['allow', 'block', 'ask'] },
   { key: 'sendConfirmation', label: 'Send Confirmation', category: 'Composer', type: 'boolean' },

components/email/__tests__/email-list-item.test.tsx

@@ -38,6 +38,7 @@ describe('EmailListItem tag badge', () => {
     useSettingsStore.setState({
       emailKeywords: [...DEFAULT_KEYWORDS],
       showPreview: false,
+      mailLayout: 'split',
     });
     useEmailStore.setState({
       selectedEmailIds: new Set<string>(),
@@ -104,4 +105,17 @@ describe('EmailListItem tag badge', () => {
     render(<EmailListItem email={email} />);
     expect(screen.getByText('Hello World')).toBeInTheDocument();
   });
+
+  it('renders inline preview text in focused mail layout', () => {
+    useSettingsStore.setState({
+      showPreview: true,
+      mailLayout: 'focus',
+    });
+    const email = makeEmail({ preview: 'Inline preview content' });
+    const { container } = render(<EmailListItem email={email} />);
+
+    expect(screen.getByText('Test Subject')).toBeInTheDocument();
+    expect(screen.getByText(/Inline preview content/)).toBeInTheDocument();
+    expect(container.querySelector('p')).toBeNull();
+  });
 });

components/email/email-list-item.tsx

@@ -35,6 +35,7 @@ export function EmailListItem({ email, selected, onClick, onContextMenu, onToggl
   const { selectedEmailIds, toggleEmailSelection, selectRangeEmails, selectedMailbox, clearSelection } = useEmailStore();
   const showPreview = useSettingsStore((state) => state.showPreview);
   const density = useSettingsStore((state) => state.density);
+  const mailLayout = useSettingsStore((state) => state.mailLayout);
   const emailKeywords = useSettingsStore((state) => state.emailKeywords);
   const { identities } = useAuthStore();
   const isChecked = selectedEmailIds.has(email.id);
@@ -44,6 +45,8 @@ export function EmailListItem({ email, selected, onClick, onContextMenu, onToggl
   const isAnswered = email.keywords?.$answered;
   const isForwarded = email.keywords?.$forwarded;
   const sender = email.from?.[0];
+  const isFocusedMailLayout = mailLayout === 'focus';
+  const inlinePreview = showPreview && email.preview ? ` ${email.preview}` : '';
 
   // Resolve color tag using keyword definitions from settings
   const colorTagId = getEmailColorTag(email.keywords);
@@ -114,15 +117,19 @@ export function EmailListItem({ email, selected, onClick, onContextMenu, onToggl
         }
       }}
       onContextMenu={handleContextMenu}
-      style={{ minHeight: 'var(--list-item-height)' }}
+      style={{ minHeight: isFocusedMailLayout ? undefined : 'var(--list-item-height)' }}
     >
-      <div className="flex items-start px-4" style={{ gap: 'var(--density-item-gap)', paddingBlock: 'var(--density-item-py)' }}>
+      <div
+        className={cn('px-4', isFocusedMailLayout ? 'flex items-center py-2.5' : 'flex items-start')}
+        style={isFocusedMailLayout ? { gap: '12px' } : { gap: 'var(--density-item-gap)', paddingBlock: 'var(--density-item-py)' }}
+      >
         {/* Checkbox - only visible when in selection mode */}
         {selectedEmailIds.size > 0 && (
           <button
             onClick={handleCheckboxClick}
             className={cn(
-              "p-3 lg:p-1 rounded mt-2 flex-shrink-0 transition-all duration-200",
+              "p-3 lg:p-1 rounded flex-shrink-0 transition-all duration-200",
+              !isFocusedMailLayout && 'mt-2',
               "hover:bg-muted/50 hover:scale-110",
               "active:scale-95",
               "animate-in fade-in zoom-in-95 duration-150",
@@ -145,7 +152,7 @@ export function EmailListItem({ email, selected, onClick, onContextMenu, onToggl
         )}
 
         {/* Avatar */}
-        {density !== 'extra-compact' && (
+        {!isFocusedMailLayout && density !== 'extra-compact' && (
           <Avatar
             name={sender?.name}
             email={sender?.email}
@@ -156,85 +163,131 @@ export function EmailListItem({ email, selected, onClick, onContextMenu, onToggl
 
         {/* Content */}
         <div className="flex-1 min-w-0">
-          {/* First Line: Sender and Date */}
+          {isFocusedMailLayout ? (
-          <div className="flex items-center justify-between gap-2 mb-1">
+            <div className="flex items-center justify-between gap-3">
-            <div className="flex items-center gap-2 min-w-0 flex-1">
+              <div className="flex min-w-0 flex-1 items-center gap-3">
-              <span className={cn(
+                <span className={cn(
-                "truncate text-sm",
+                  'w-32 shrink-0 truncate text-sm lg:w-40',
-                isUnread
+                  isUnread ? 'font-semibold text-foreground' : 'font-medium text-foreground/80'
-                  ? "font-bold text-foreground"
+                )}>
-                  : "font-medium text-muted-foreground"
+                  {sender?.name || sender?.email || 'Unknown'}
-              )}>
+                </span>
-                {sender?.name || sender?.email || "Unknown"}
+                <div className="flex min-w-0 flex-1 items-center gap-2 text-sm">
-              </span>
+                  <span className={cn(
-              <div className="flex items-center gap-1.5">
+                    'shrink-0 truncate',
-                {isStarred && (
+                    isUnread ? 'font-semibold text-foreground' : 'text-foreground/90'
-                  <Star className="w-3.5 h-3.5 fill-amber-400 text-amber-400" />
+                  )}>
-                )}
+                    {email.subject || t('no_subject')}
-                {isImportant && (
-                  <span className="px-1.5 py-0.5 text-xs bg-warning/15 text-warning dark:text-warning rounded font-medium">
-                    Important
                   </span>
-                )}
+                  {inlinePreview && (
-                <EmailIdentityBadge email={email} identities={identities} compact={true} />
+                    <span className="min-w-0 truncate text-muted-foreground">{inlinePreview}</span>
-                {isAnswered && !isForwarded && (
+                  )}
-                  <Reply className="w-3.5 h-3.5 text-muted-foreground" />
+                </div>
-                )}
+              </div>
-                {isForwarded && !isAnswered && (
+              <div className="flex items-center gap-2.5 shrink-0">
-                  <Forward className="w-3.5 h-3.5 text-muted-foreground" />
+                {isStarred && <Star className="w-3.5 h-3.5 fill-amber-400 text-amber-400" />}
-                )}
+                {isImportant && <span className="h-2 w-2 rounded-full bg-warning" />}
+                {isAnswered && !isForwarded && <Reply className="w-3.5 h-3.5 text-muted-foreground" />}
+                {isForwarded && !isAnswered && <Forward className="w-3.5 h-3.5 text-muted-foreground" />}
                 {isAnswered && isForwarded && (
                   <>
                     <Reply className="w-3.5 h-3.5 text-muted-foreground" />
                     <Forward className="w-3.5 h-3.5 text-muted-foreground" />
                   </>
                 )}
-                {email.hasAttachment && (
+                {email.hasAttachment && <Paperclip className="w-3.5 h-3.5 text-muted-foreground" />}
-                  <Paperclip className="w-3.5 h-3.5 text-muted-foreground" />
+                {keywordDef && <span className={cn('h-2.5 w-2.5 rounded-full', KEYWORD_PALETTE[keywordDef.color]?.dot || 'bg-gray-400')} />}
-                )}
+                <span className={cn(
+                  'text-xs tabular-nums',
+                  isUnread ? 'text-foreground font-semibold' : 'text-muted-foreground'
+                )}>
+                  {formatDate(email.receivedAt)}
+                </span>
               </div>
             </div>
-            <div className="flex items-center gap-1.5 flex-shrink-0">
+          ) : (
-              {keywordDef && (
+            <>
-                <span className={cn(
+              {/* First Line: Sender and Date */}
-                  "inline-flex items-center gap-1 px-1.5 py-0.5 text-[10px] font-medium rounded-full",
+              <div className="flex items-center justify-between gap-2 mb-1">
-                  KEYWORD_PALETTE[keywordDef.color]?.bg || "bg-muted"
+                <div className="flex items-center gap-2 min-w-0 flex-1">
-                )}>
+                  <span className={cn(
-                  <span className={cn("w-1.5 h-1.5 rounded-full", KEYWORD_PALETTE[keywordDef.color]?.dot || "bg-gray-400")} />
+                    "truncate text-sm",
-                  {keywordDef.label}
+                    isUnread
-                </span>
+                      ? "font-bold text-foreground"
-              )}
+                      : "font-medium text-muted-foreground"
-              <span className={cn(
+                  )}>
-                "text-xs tabular-nums",
+                    {sender?.name || sender?.email || "Unknown"}
+                  </span>
+                  <div className="flex items-center gap-1.5">
+                    {isStarred && (
+                      <Star className="w-3.5 h-3.5 fill-amber-400 text-amber-400" />
+                    )}
+                    {isImportant && (
+                      <span className="px-1.5 py-0.5 text-xs bg-warning/15 text-warning dark:text-warning rounded font-medium">
+                        Important
+                      </span>
+                    )}
+                    <EmailIdentityBadge email={email} identities={identities} compact={true} />
+                    {isAnswered && !isForwarded && (
+                      <Reply className="w-3.5 h-3.5 text-muted-foreground" />
+                    )}
+                    {isForwarded && !isAnswered && (
+                      <Forward className="w-3.5 h-3.5 text-muted-foreground" />
+                    )}
+                    {isAnswered && isForwarded && (
+                      <>
+                        <Reply className="w-3.5 h-3.5 text-muted-foreground" />
+                        <Forward className="w-3.5 h-3.5 text-muted-foreground" />
+                      </>
+                    )}
+                    {email.hasAttachment && (
+                      <Paperclip className="w-3.5 h-3.5 text-muted-foreground" />
+                    )}
+                  </div>
+                </div>
+                <div className="flex items-center gap-1.5 flex-shrink-0">
+                  {keywordDef && (
+                    <span className={cn(
+                      "inline-flex items-center gap-1 px-1.5 py-0.5 text-[10px] font-medium rounded-full",
+                      KEYWORD_PALETTE[keywordDef.color]?.bg || "bg-muted"
+                    )}>
+                      <span className={cn("w-1.5 h-1.5 rounded-full", KEYWORD_PALETTE[keywordDef.color]?.dot || "bg-gray-400")} />
+                      {keywordDef.label}
+                    </span>
+                  )}
+                  <span className={cn(
+                    "text-xs tabular-nums",
+                    isUnread
+                      ? "text-foreground font-semibold"
+                      : "text-muted-foreground"
+                  )}>
+                    {formatDate(email.receivedAt)}
+                  </span>
+                </div>
+              </div>
+
+              {/* Second Line: Subject */}
+              <div className={cn(
+                "mb-1 line-clamp-1 text-sm",
                 isUnread
-                  ? "text-foreground font-semibold"
+                  ? "font-semibold text-foreground"
-                  : "text-muted-foreground"
+                  : "font-normal text-foreground/90"
               )}>
-                {formatDate(email.receivedAt)}
+                {email.subject || t('no_subject')}
-              </span>
+              </div>
-            </div>
-          </div>
 
-          {/* Second Line: Subject */}
+              {/* Third Line: Preview (controlled by showPreview setting) */}
-          <div className={cn(
+              {showPreview && density !== 'extra-compact' && (
-            "mb-1 line-clamp-1 text-sm",
+                <p className={cn(
-            isUnread
+                  "text-sm leading-relaxed line-clamp-2",
-              ? "font-semibold text-foreground"
+                  isUnread
-              : "font-normal text-foreground/90"
+                    ? "text-muted-foreground"
-          )}>
+                    : "text-muted-foreground/80"
-            {email.subject || t('no_subject')}
+                )}>
-          </div>
+                  {email.preview || "No preview available"}
-
+                </p>
-          {/* Third Line: Preview (controlled by showPreview setting) */}
+              )}
-          {showPreview && density !== 'extra-compact' && (
+            </>
-            <p className={cn(
-              "text-sm leading-relaxed line-clamp-2",
-              isUnread
-                ? "text-muted-foreground"
-                : "text-muted-foreground/80"
-            )}>
-              {email.preview || "No preview available"}
-            </p>
           )}
         </div>
       </div>

components/email/email-list.tsx

@@ -103,11 +103,16 @@ export function EmailList({
   const parentRef = useRef<HTMLDivElement>(null);
   const density = useSettingsStore((state) => state.density);
   const showPreview = useSettingsStore((state) => state.showPreview);
+  const mailLayout = useSettingsStore((state) => state.mailLayout);
+  const isFocusedMailLayout = mailLayout === 'focus';
 
   const estimateSize = useCallback(() => {
+    if (isFocusedMailLayout) {
+      return { 'extra-compact': 32, compact: 40, regular: 46, comfortable: 54 }[density];
+    }
     const base = { 'extra-compact': 32, compact: 60, regular: 84, comfortable: 104 }[density];
     return (showPreview && density !== 'extra-compact') ? base + 36 : base;
-  }, [density, showPreview]);
+  }, [density, isFocusedMailLayout, showPreview]);
 
   const virtualizer = useVirtualizer({
     count: threadGroups.length,
@@ -244,7 +249,7 @@ export function EmailList({
   useEffect(() => {
     virtualizer.measure();
     // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [density, showPreview]);
+  }, [density, isFocusedMailLayout, showPreview]);
 
   return (
     <div className={cn("flex flex-col min-h-0", className)}>

components/email/email-viewer.tsx

@@ -887,8 +887,10 @@ export function EmailViewer({
   const emailKeywords = useSettingsStore((state) => state.emailKeywords);
   const toolbarPosition = useSettingsStore((state) => state.toolbarPosition);
   const showToolbarLabels = useSettingsStore((state) => state.showToolbarLabels);
+  const mailLayout = useSettingsStore((state) => state.mailLayout);
   const calendarInvitationParsingEnabled = useSettingsStore((state) => state.calendarInvitationParsingEnabled);
   const timeFormat = useSettingsStore((state) => state.timeFormat);
+  const isFocusedMailLayout = mailLayout === 'focus';
 
   // Detect if current mailbox is Junk folder
   const isInJunkFolder = currentMailboxRole === 'junk';
@@ -2790,7 +2792,7 @@ export function EmailViewer({
     <>
       {/* Left: Reply actions */}
       <div className={cn("flex items-center gap-0", showBackButton ? "sm:gap-1" : "sm:gap-0.5")}>
-        {showBackButton && isTablet && !tabletListVisible && onBack && (
+        {showBackButton && ((isTablet && !tabletListVisible) || (isFocusedMailLayout && !isMobile)) && onBack && (
           <Button
             variant="ghost"
             size="icon"
@@ -3524,7 +3526,7 @@ export function EmailViewer({
         <div className="px-4 lg:px-6" style={{ paddingBlock: 'var(--density-header-py)' }}>
           <div className="flex items-start justify-between gap-2 lg:gap-4">
             {/* Back button (for below-subject mode on tablet) */}
-            {toolbarPosition === 'below-subject' && isTablet && !tabletListVisible && onBack && (
+            {toolbarPosition === 'below-subject' && ((isTablet && !tabletListVisible) || (isFocusedMailLayout && !isMobile)) && onBack && (
               <Button
                 variant="ghost"
                 size="icon"

components/email/thread-list-item.tsx

@@ -59,7 +59,10 @@ const SingleEmailItem = React.forwardRef<HTMLDivElement, SingleEmailItemProps>(
     const { selectedMailbox, selectedEmailIds, toggleEmailSelection, selectRangeEmails, clearSelection } = useEmailStore();
     const emailKeywords = useSettingsStore((state) => state.emailKeywords);
     const density = useSettingsStore((state) => state.density);
+    const mailLayout = useSettingsStore((state) => state.mailLayout);
     const isChecked = selectedEmailIds.has(email.id);
+    const isFocusedMailLayout = mailLayout === 'focus';
+    const inlinePreview = showPreview && email.preview ? ` ${email.preview}` : '';
 
     // Resolve color and keyword definition from keyword definitions if not passed directly
     const tagId = getEmailColorTag(email.keywords);
@@ -131,15 +134,19 @@ const SingleEmailItem = React.forwardRef<HTMLDivElement, SingleEmailItemProps>(
         )}
         onClick={handleClick}
         onContextMenu={handleContextMenu}
-        style={{ minHeight: 'var(--list-item-height)' }}
+        style={{ minHeight: isFocusedMailLayout ? undefined : 'var(--list-item-height)' }}
       >
-        <div className="flex items-start px-3" style={{ gap: 'var(--density-item-gap)', paddingBlock: 'var(--density-item-py)' }}>
+        <div
+          className={cn('px-3', isFocusedMailLayout ? 'flex items-center py-2.5' : 'flex items-start')}
+          style={isFocusedMailLayout ? { gap: '12px' } : { gap: 'var(--density-item-gap)', paddingBlock: 'var(--density-item-py)' }}
+        >
           {/* Checkbox - only visible when in selection mode */}
           {selectedEmailIds.size > 0 && (
             <button
               onClick={handleCheckboxClick}
               className={cn(
-                "p-3 lg:p-1 rounded mt-2 flex-shrink-0 transition-all duration-200",
+                "p-3 lg:p-1 rounded flex-shrink-0 transition-all duration-200",
+                !isFocusedMailLayout && 'mt-2',
                 "hover:bg-muted/50 hover:scale-110",
                 "active:scale-95",
                 "animate-in fade-in zoom-in-95 duration-150",
@@ -160,7 +167,7 @@ const SingleEmailItem = React.forwardRef<HTMLDivElement, SingleEmailItemProps>(
             </div>
           )}
 
-          {density !== 'extra-compact' && (
+          {!isFocusedMailLayout && density !== 'extra-compact' && (
             <Avatar
               name={sender?.name}
               email={sender?.email}
@@ -170,76 +177,121 @@ const SingleEmailItem = React.forwardRef<HTMLDivElement, SingleEmailItemProps>(
           )}
 
           <div className="flex-1 min-w-0">
-            <div className="flex items-center justify-between gap-2 mb-1">
+            {isFocusedMailLayout ? (
-              <div className="flex items-center gap-2 min-w-0 flex-1">
+              <div className="flex items-center justify-between gap-3">
-                <span className={cn(
+                <div className="flex min-w-0 flex-1 items-center gap-3">
-                  "truncate text-sm",
+                  <span className={cn(
-                  isUnread
+                    'w-32 shrink-0 truncate text-sm lg:w-40',
-                    ? "font-bold text-foreground"
+                    isUnread ? 'font-semibold text-foreground' : 'font-medium text-foreground/80'
-                    : "font-medium text-muted-foreground"
+                  )}>
-                )}>
+                    {sender?.name || sender?.email || 'Unknown'}
-                  {sender?.name || sender?.email || "Unknown"}
+                  </span>
-                </span>
+                  <div className="flex min-w-0 flex-1 items-center gap-2 text-sm">
-                <div className="flex items-center gap-1.5">
+                    <span className={cn(
-                  {isStarred && (
+                      'shrink-0 truncate',
-                    <Star className="w-3.5 h-3.5 fill-amber-400 text-amber-400" />
+                      isUnread ? 'font-semibold text-foreground' : 'text-foreground/90'
-                  )}
+                    )}>
-                  {isAnswered && !isForwarded && (
+                      {email.subject || '(no subject)'}
-                    <Reply className="w-3.5 h-3.5 text-muted-foreground" />
+                    </span>
-                  )}
+                    {inlinePreview && (
-                  {isForwarded && !isAnswered && (
+                      <span className="min-w-0 truncate text-muted-foreground">{inlinePreview}</span>
-                    <Forward className="w-3.5 h-3.5 text-muted-foreground" />
+                    )}
-                  )}
+                  </div>
+                </div>
+                <div className="flex items-center gap-2.5 shrink-0">
+                  {isStarred && <Star className="w-3.5 h-3.5 fill-amber-400 text-amber-400" />}
+                  {isAnswered && !isForwarded && <Reply className="w-3.5 h-3.5 text-muted-foreground" />}
+                  {isForwarded && !isAnswered && <Forward className="w-3.5 h-3.5 text-muted-foreground" />}
                   {isAnswered && isForwarded && (
                     <>
                       <Reply className="w-3.5 h-3.5 text-muted-foreground" />
                       <Forward className="w-3.5 h-3.5 text-muted-foreground" />
                     </>
                   )}
-                  {email.hasAttachment && (
+                  {email.hasAttachment && <Paperclip className="w-3.5 h-3.5 text-muted-foreground" />}
-                    <Paperclip className="w-3.5 h-3.5 text-muted-foreground" />
+                  {resolvedKeywordDef && <span className={cn('h-2.5 w-2.5 rounded-full', KEYWORD_PALETTE[resolvedKeywordDef.color]?.dot || 'bg-gray-400')} />}
-                  )}
+                  <span className={cn(
+                    'text-xs tabular-nums',
+                    isUnread ? 'text-foreground font-semibold' : 'text-muted-foreground'
+                  )}>
+                    {formatDate(email.receivedAt)}
+                  </span>
                 </div>
               </div>
-              <div className="flex items-center gap-1.5 flex-shrink-0">
+            ) : (
-                {resolvedKeywordDef && (
+              <>
-                  <span className={cn(
+                <div className="flex items-center justify-between gap-2 mb-1">
-                    "inline-flex items-center gap-1 px-1.5 py-0.5 text-[10px] font-medium rounded-full",
+                  <div className="flex items-center gap-2 min-w-0 flex-1">
-                    KEYWORD_PALETTE[resolvedKeywordDef.color]?.bg || "bg-muted"
+                    <span className={cn(
-                  )}>
+                      "truncate text-sm",
-                    <span className={cn("w-1.5 h-1.5 rounded-full", KEYWORD_PALETTE[resolvedKeywordDef.color]?.dot || "bg-gray-400")} />
+                      isUnread
-                    {resolvedKeywordDef.label}
+                        ? "font-bold text-foreground"
-                  </span>
+                        : "font-medium text-muted-foreground"
-                )}
+                    )}>
-                <span className={cn(
+                      {sender?.name || sender?.email || "Unknown"}
-                  "text-xs tabular-nums",
+                    </span>
+                    <div className="flex items-center gap-1.5">
+                      {isStarred && (
+                        <Star className="w-3.5 h-3.5 fill-amber-400 text-amber-400" />
+                      )}
+                      {isAnswered && !isForwarded && (
+                        <Reply className="w-3.5 h-3.5 text-muted-foreground" />
+                      )}
+                      {isForwarded && !isAnswered && (
+                        <Forward className="w-3.5 h-3.5 text-muted-foreground" />
+                      )}
+                      {isAnswered && isForwarded && (
+                        <>
+                          <Reply className="w-3.5 h-3.5 text-muted-foreground" />
+                          <Forward className="w-3.5 h-3.5 text-muted-foreground" />
+                        </>
+                      )}
+                      {email.hasAttachment && (
+                        <Paperclip className="w-3.5 h-3.5 text-muted-foreground" />
+                      )}
+                    </div>
+                  </div>
+                  <div className="flex items-center gap-1.5 flex-shrink-0">
+                    {resolvedKeywordDef && (
+                      <span className={cn(
+                        "inline-flex items-center gap-1 px-1.5 py-0.5 text-[10px] font-medium rounded-full",
+                        KEYWORD_PALETTE[resolvedKeywordDef.color]?.bg || "bg-muted"
+                      )}>
+                        <span className={cn("w-1.5 h-1.5 rounded-full", KEYWORD_PALETTE[resolvedKeywordDef.color]?.dot || "bg-gray-400")} />
+                        {resolvedKeywordDef.label}
+                      </span>
+                    )}
+                    <span className={cn(
+                      "text-xs tabular-nums",
+                      isUnread
+                        ? "text-foreground font-semibold"
+                        : "text-muted-foreground"
+                    )}>
+                      {formatDate(email.receivedAt)}
+                    </span>
+                  </div>
+                </div>
+
+                <div className={cn(
+                  "mb-1 line-clamp-1 text-sm",
                   isUnread
-                    ? "text-foreground font-semibold"
+                    ? "font-semibold text-foreground"
-                    : "text-muted-foreground"
+                    : "font-normal text-foreground/90"
                 )}>
-                  {formatDate(email.receivedAt)}
+                  {email.subject || "(no subject)"}
-                </span>
+                </div>
-              </div>
-            </div>
 
-            <div className={cn(
+                {showPreview && density !== 'extra-compact' && (
-              "mb-1 line-clamp-1 text-sm",
+                  <p className={cn(
-              isUnread
+                    "text-sm leading-relaxed line-clamp-2",
-                ? "font-semibold text-foreground"
+                    isUnread
-                : "font-normal text-foreground/90"
+                      ? "text-muted-foreground"
-            )}>
+                      : "text-muted-foreground/80"
-              {email.subject || "(no subject)"}
+                  )}>
-            </div>
+                    {email.preview || "No preview available"}
-
+                  </p>
-            {showPreview && density !== 'extra-compact' && (
+                )}
-              <p className={cn(
+              </>
-                "text-sm leading-relaxed line-clamp-2",
-                isUnread
-                  ? "text-muted-foreground"
-                  : "text-muted-foreground/80"
-              )}>
-                {email.preview || "No preview available"}
-              </p>
             )}
           </div>
         </div>
@@ -281,8 +333,11 @@ export const ThreadListItem = React.forwardRef<HTMLDivElement, ThreadListItemPro
     const t = useTranslations('threads');
     const showPreview = useSettingsStore((state) => state.showPreview);
     const density = useSettingsStore((state) => state.density);
+    const mailLayout = useSettingsStore((state) => state.mailLayout);
     const isMobile = useUIStore((state) => state.isMobile);
     const { latestEmail, participantNames, hasUnread, hasStarred, hasAttachment, hasAnswered, hasForwarded, emailCount } = thread;
+    const isFocusedMailLayout = mailLayout === 'focus';
+    const inlinePreview = showPreview && latestEmail.preview ? ` ${latestEmail.preview}` : '';
 
     const { selectedMailbox, selectedEmailIds, toggleEmailSelection, selectRangeEmails, clearSelection } = useEmailStore();
 
@@ -406,15 +461,19 @@ export const ThreadListItem = React.forwardRef<HTMLDivElement, ThreadListItemPro
           )}
           onClick={handleHeaderClick}
           onContextMenu={handleContextMenu}
-          style={{ minHeight: 'var(--list-item-height)' }}
+          style={{ minHeight: isFocusedMailLayout ? undefined : 'var(--list-item-height)' }}
         >
-          <div className="flex items-start px-3" style={{ gap: 'var(--density-item-gap)', paddingBlock: 'var(--density-item-py)' }}>
+          <div
+            className={cn('px-3', isFocusedMailLayout ? 'flex items-center py-2.5' : 'flex items-start')}
+            style={isFocusedMailLayout ? { gap: '12px' } : { gap: 'var(--density-item-gap)', paddingBlock: 'var(--density-item-py)' }}
+          >
             {/* Checkbox for thread selection - only visible when in selection mode */}
             {selectedEmailIds.size > 0 && (
               <button
                 onClick={handleThreadCheckboxClick}
                 className={cn(
-                  "p-3 lg:p-1 rounded mt-2 flex-shrink-0 transition-all duration-200",
+                  "p-3 lg:p-1 rounded flex-shrink-0 transition-all duration-200",
+                  !isFocusedMailLayout && 'mt-2',
                   "hover:bg-muted/50 hover:scale-110",
                   "active:scale-95",
                   "animate-in fade-in zoom-in-95 duration-150",
@@ -429,7 +488,7 @@ export const ThreadListItem = React.forwardRef<HTMLDivElement, ThreadListItemPro
               </button>
             )}
 
-            {!isMobile && (
+            {!isMobile && !isFocusedMailLayout && (
               <button
                 data-expand-toggle
                 onClick={(e) => {
@@ -461,7 +520,7 @@ export const ThreadListItem = React.forwardRef<HTMLDivElement, ThreadListItemPro
               </div>
             )}
 
-            {density !== 'extra-compact' && (
+            {!isFocusedMailLayout && density !== 'extra-compact' && (
               <Avatar
                 name={latestEmail.from?.[0]?.name}
                 email={latestEmail.from?.[0]?.email}
@@ -471,88 +530,143 @@ export const ThreadListItem = React.forwardRef<HTMLDivElement, ThreadListItemPro
             )}
 
             <div className="flex-1 min-w-0">
-              <div className="flex items-center justify-between gap-2 mb-1">
+              {isFocusedMailLayout ? (
-                <div className="flex items-center gap-2 min-w-0 flex-1">
+                <div className="flex items-center justify-between gap-3">
-                  <span className={cn(
+                  <div className="flex min-w-0 flex-1 items-center gap-3">
-                    "truncate text-sm",
+                    <span className={cn(
-                    hasUnread
+                      'w-32 shrink-0 truncate text-sm lg:w-44',
-                      ? "font-bold text-foreground"
+                      hasUnread ? 'font-semibold text-foreground' : 'font-medium text-foreground/80'
-                      : "font-medium text-muted-foreground"
+                    )}>
-                  )}>
+                      {participantNames.join(', ')}
-                    {participantNames.join(", ")}
+                    </span>
-                  </span>
+                    <span
-                  <span
+                      className={cn(
-                    className={cn(
+                        'inline-flex shrink-0 items-center gap-0.5 rounded-full px-1.5 py-0.5 text-xs font-medium',
-                      "flex-shrink-0 inline-flex items-center gap-0.5 px-1.5 py-0.5 text-xs rounded-full font-medium",
+                        hasUnread ? 'bg-primary text-primary-foreground' : 'bg-muted text-muted-foreground'
-                      hasUnread
+                      )}
-                        ? "bg-primary text-primary-foreground"
+                      title={t('messages_tooltip', { count: emailCount })}
-                        : "bg-muted text-muted-foreground"
+                    >
-                    )}
+                      <MessageSquare className="w-3 h-3" />
-                    title={t('messages_tooltip', { count: emailCount })}
+                      {emailCount}
-                  >
+                    </span>
-                    <MessageSquare className="w-3 h-3" />
+                    <div className="flex min-w-0 flex-1 items-center gap-2 text-sm">
-                    {emailCount}
+                      <span className={cn(
-                  </span>
+                        'shrink-0 truncate',
-                  <div className="flex items-center gap-1.5">
+                        hasUnread ? 'font-semibold text-foreground' : 'text-foreground/90'
-                    {hasStarred && (
+                      )}>
-                      <Star className="w-3.5 h-3.5 fill-amber-400 text-amber-400" />
+                        {latestEmail.subject || '(no subject)'}
-                    )}
+                      </span>
-                    {hasAnswered && !hasForwarded && (
+                      {inlinePreview && (
-                      <Reply className="w-3.5 h-3.5 text-muted-foreground" />
+                        <span className="min-w-0 truncate text-muted-foreground">{inlinePreview}</span>
-                    )}
+                      )}
-                    {hasForwarded && !hasAnswered && (
+                    </div>
-                      <Forward className="w-3.5 h-3.5 text-muted-foreground" />
+                  </div>
-                    )}
+                  <div className="flex items-center gap-2.5 shrink-0">
+                    {hasStarred && <Star className="w-3.5 h-3.5 fill-amber-400 text-amber-400" />}
+                    {hasAnswered && !hasForwarded && <Reply className="w-3.5 h-3.5 text-muted-foreground" />}
+                    {hasForwarded && !hasAnswered && <Forward className="w-3.5 h-3.5 text-muted-foreground" />}
                     {hasAnswered && hasForwarded && (
                       <>
                         <Reply className="w-3.5 h-3.5 text-muted-foreground" />
                         <Forward className="w-3.5 h-3.5 text-muted-foreground" />
                       </>
                     )}
-                    {hasAttachment && (
+                    {hasAttachment && <Paperclip className="w-3.5 h-3.5 text-muted-foreground" />}
-                      <Paperclip className="w-3.5 h-3.5 text-muted-foreground" />
+                    {keywordDef && <span className={cn('h-2.5 w-2.5 rounded-full', KEYWORD_PALETTE[keywordDef.color]?.dot || 'bg-gray-400')} />}
-                    )}
+                    <span className={cn(
+                      'text-xs tabular-nums',
+                      hasUnread ? 'text-foreground font-semibold' : 'text-muted-foreground'
+                    )}>
+                      {formatDate(latestEmail.receivedAt)}
+                    </span>
                   </div>
                 </div>
-                <div className="flex items-center gap-1.5 flex-shrink-0">
+              ) : (
-                  {keywordDef && (
+                <>
-                    <span className={cn(
+                  <div className="flex items-center justify-between gap-2 mb-1">
-                      "inline-flex items-center gap-1 px-1.5 py-0.5 text-[10px] font-medium rounded-full",
+                    <div className="flex items-center gap-2 min-w-0 flex-1">
-                      KEYWORD_PALETTE[keywordDef.color]?.bg || "bg-muted"
+                      <span className={cn(
-                    )}>
+                        "truncate text-sm",
-                      <span className={cn("w-1.5 h-1.5 rounded-full", KEYWORD_PALETTE[keywordDef.color]?.dot || "bg-gray-400")} />
+                        hasUnread
-                      {keywordDef.label}
+                          ? "font-bold text-foreground"
-                    </span>
+                          : "font-medium text-muted-foreground"
-                  )}
+                      )}>
-                  <span className={cn(
+                        {participantNames.join(", ")}
-                    "text-xs tabular-nums",
+                      </span>
+                      <span
+                        className={cn(
+                          "flex-shrink-0 inline-flex items-center gap-0.5 px-1.5 py-0.5 text-xs rounded-full font-medium",
+                          hasUnread
+                            ? "bg-primary text-primary-foreground"
+                            : "bg-muted text-muted-foreground"
+                        )}
+                        title={t('messages_tooltip', { count: emailCount })}
+                      >
+                        <MessageSquare className="w-3 h-3" />
+                        {emailCount}
+                      </span>
+                      <div className="flex items-center gap-1.5">
+                        {hasStarred && (
+                          <Star className="w-3.5 h-3.5 fill-amber-400 text-amber-400" />
+                        )}
+                        {hasAnswered && !hasForwarded && (
+                          <Reply className="w-3.5 h-3.5 text-muted-foreground" />
+                        )}
+                        {hasForwarded && !hasAnswered && (
+                          <Forward className="w-3.5 h-3.5 text-muted-foreground" />
+                        )}
+                        {hasAnswered && hasForwarded && (
+                          <>
+                            <Reply className="w-3.5 h-3.5 text-muted-foreground" />
+                            <Forward className="w-3.5 h-3.5 text-muted-foreground" />
+                          </>
+                        )}
+                        {hasAttachment && (
+                          <Paperclip className="w-3.5 h-3.5 text-muted-foreground" />
+                        )}
+                      </div>
+                    </div>
+                    <div className="flex items-center gap-1.5 flex-shrink-0">
+                      {keywordDef && (
+                        <span className={cn(
+                          "inline-flex items-center gap-1 px-1.5 py-0.5 text-[10px] font-medium rounded-full",
+                          KEYWORD_PALETTE[keywordDef.color]?.bg || "bg-muted"
+                        )}>
+                          <span className={cn("w-1.5 h-1.5 rounded-full", KEYWORD_PALETTE[keywordDef.color]?.dot || "bg-gray-400")} />
+                          {keywordDef.label}
+                        </span>
+                      )}
+                      <span className={cn(
+                        "text-xs tabular-nums",
+                        hasUnread
+                          ? "text-foreground font-semibold"
+                          : "text-muted-foreground"
+                      )}>
+                        {formatDate(latestEmail.receivedAt)}
+                      </span>
+                    </div>
+                  </div>
+
+                  <div className={cn(
+                    "mb-1 line-clamp-1 text-sm",
                     hasUnread
-                      ? "text-foreground font-semibold"
+                      ? "font-semibold text-foreground"
-                      : "text-muted-foreground"
+                      : "font-normal text-foreground/90"
                   )}>
-                    {formatDate(latestEmail.receivedAt)}
+                    {latestEmail.subject || "(no subject)"}
-                  </span>
+                  </div>
-                </div>
-              </div>
 
-              <div className={cn(
+                  {showPreview && density !== 'extra-compact' && (
-                "mb-1 line-clamp-1 text-sm",
+                    <p className={cn(
-                hasUnread
+                      "text-sm leading-relaxed line-clamp-2",
-                  ? "font-semibold text-foreground"
+                      hasUnread
-                  : "font-normal text-foreground/90"
+                        ? "text-muted-foreground"
-              )}>
+                        : "text-muted-foreground/80"
-                {latestEmail.subject || "(no subject)"}
+                    )}>
-              </div>
+                      {latestEmail.preview || "No preview available"}
-
+                    </p>
-              {showPreview && density !== 'extra-compact' && (
+                  )}
-                <p className={cn(
+                </>
-                  "text-sm leading-relaxed line-clamp-2",
-                  hasUnread
-                    ? "text-muted-foreground"
-                    : "text-muted-foreground/80"
-                )}>
-                  {latestEmail.preview || "No preview available"}
-                </p>
               )}
             </div>
           </div>
@@ -570,7 +684,7 @@ export const ThreadListItem = React.forwardRef<HTMLDivElement, ThreadListItemPro
           />
         </div>
 
-        {isExpanded && !isMobile && (
+        {isExpanded && !isMobile && !isFocusedMailLayout && (
           <div className="bg-muted/20 animate-in slide-in-from-top-2 duration-200">
             {isLoading ? (
               <div className="py-4 flex items-center justify-center text-sm text-muted-foreground">

components/settings/email-settings.tsx

@@ -4,16 +4,92 @@ import { useState, useCallback } from 'react';
 import { useTranslations } from 'next-intl';
 import { useConfig } from '@/hooks/use-config';
 import { useSettingsStore } from '@/stores/settings-store';
-import type { ArchiveMode, HoverAction } from '@/stores/settings-store';
+import type { ArchiveMode, HoverAction, MailLayout } from '@/stores/settings-store';
 import { ALL_HOVER_ACTIONS } from '@/stores/settings-store';
 import { useAuthStore } from '@/stores/auth-store';
 import { useEmailStore } from '@/stores/email-store';
 import { cn } from '@/lib/utils';
-import { SettingsSection, SettingItem, Select, ToggleSwitch } from './settings-section';
+import { RadioGroup, SettingsSection, SettingItem, Select, ToggleSwitch } from './settings-section';
 import { TrustedSendersModal } from '@/components/trusted-senders-modal';
 import { ChevronRight, AlertTriangle, FolderSync, Loader2, Mail } from 'lucide-react';
 import { usePolicyStore } from '@/stores/policy-store';
 
+const MAIL_LAYOUT_PREVIEW_ROWS = [
+  { sender: 'Alice', subject: 'Quarterly roadmap', preview: 'The draft is ready for review.', selected: false },
+  { sender: 'Nadia', subject: 'Design sync', preview: 'Pushed updated mocks and notes.', selected: true },
+  { sender: 'Billing', subject: 'Invoice 1042', preview: 'Your receipt is attached.', selected: false },
+];
+
+function MailLayoutPreview({
+  value,
+  t,
+}: {
+  value: MailLayout;
+  t: (key: string) => string;
+}) {
+  const isSplit = value === 'split';
+
+  return (
+    <div className="mt-3 rounded-xl border border-border bg-background p-3">
+      <div>
+        <div className="text-sm font-medium text-foreground">{t(`mail_layout.${value}`)}</div>
+        <div className="mt-1 text-xs text-muted-foreground">{t(`mail_layout.${value}_description`)}</div>
+      </div>
+
+      <div className="mt-3 overflow-hidden rounded-lg border border-border bg-muted/20">
+        <div className="flex h-28">
+          <div className="w-11 border-r border-border bg-muted/40" />
+
+          {isSplit ? (
+            <>
+              <div className="w-28 border-r border-border bg-background">
+                {MAIL_LAYOUT_PREVIEW_ROWS.map((row) => (
+                  <div
+                    key={row.subject}
+                    className={cn(
+                      'border-b border-border px-2 py-1.5 text-[10px] last:border-b-0',
+                      row.selected && 'bg-primary/10'
+                    )}
+                  >
+                    <div className="truncate font-medium text-foreground">{row.sender}</div>
+                    <div className="truncate text-muted-foreground">{row.subject}</div>
+                  </div>
+                ))}
+              </div>
+              <div className="flex-1 bg-background px-3 py-2">
+                <div className="h-2.5 w-20 rounded bg-foreground/10" />
+                <div className="mt-2 h-2 w-full rounded bg-foreground/10" />
+                <div className="mt-1.5 h-2 w-5/6 rounded bg-foreground/10" />
+                <div className="mt-1.5 h-2 w-2/3 rounded bg-foreground/10" />
+              </div>
+            </>
+          ) : (
+            <div className="flex-1 bg-background px-2 py-2">
+              <div className="space-y-1.5">
+                {MAIL_LAYOUT_PREVIEW_ROWS.map((row) => (
+                  <div
+                    key={row.subject}
+                    className={cn(
+                      'rounded-md px-2 py-1 text-[10px]',
+                      row.selected ? 'bg-primary/10' : 'bg-muted/20'
+                    )}
+                  >
+                    <div className="truncate text-foreground">
+                      <span className="font-medium">{row.sender}</span>
+                      <span className="mx-1.5 text-muted-foreground">{row.subject}</span>
+                      <span className="text-muted-foreground/80">{row.preview}</span>
+                    </div>
+                  </div>
+                ))}
+              </div>
+            </div>
+          )}
+        </div>
+      </div>
+    </div>
+  );
+}
+
 export function EmailSettings() {
   const t = useTranslations('settings.email_behavior');
   const { appName } = useConfig();
@@ -39,6 +115,7 @@ export function EmailSettings() {
     deleteAction,
     permanentlyDeleteJunk,
     showPreview,
+    mailLayout,
     disableThreading,
     autoSelectReplyIdentity,
     plainTextMode,
@@ -63,6 +140,8 @@ export function EmailSettings() {
     return t('trusted_senders.count_other', { count });
   };
 
+  const isFocusedLayout = mailLayout === 'focus';
+
   const handleReorganizeArchive = async () => {
     const { client } = useAuthStore.getState();
     const { mailboxes, fetchMailboxes } = useEmailStore.getState();
@@ -208,9 +287,29 @@ export function EmailSettings() {
         />
       </SettingItem>
 
+      {!isSettingHidden('mailLayout') && (
+      <SettingItem label={t('mail_layout.label')} description={t('mail_layout.description')} locked={isSettingLocked('mailLayout')}>
+        <div className="w-[22rem] max-w-full">
+          <RadioGroup
+            value={mailLayout}
+            onChange={(value) => updateSetting('mailLayout', value as MailLayout)}
+            options={[
+              { value: 'split', label: t('mail_layout.split') },
+              { value: 'focus', label: t('mail_layout.focus') },
+            ]}
+          />
+          <MailLayoutPreview value={mailLayout} t={t} />
+        </div>
+      </SettingItem>
+      )}
+
       {/* Show Preview */}
       {!isSettingHidden('showPreview') && (
-      <SettingItem label={t('show_preview.label')} description={t('show_preview.description')} locked={isSettingLocked('showPreview')}>
+      <SettingItem
+        label={t('show_preview.label')}
+        description={isFocusedLayout ? t('show_preview.focus_description') : t('show_preview.description')}
+        locked={isSettingLocked('showPreview')}
+      >
         <ToggleSwitch checked={showPreview} onChange={(checked) => updateSetting('showPreview', checked)} />
       </SettingItem>
       )}

locales/en/common.json

@@ -799,9 +799,18 @@
         "label": "Permanently Delete Junk",
         "description": "Permanently delete emails from the Junk/Spam folder instead of moving them to Trash"
       },
+      "mail_layout": {
+        "label": "Mail Layout",
+        "description": "Choose between the classic split reading pane and a Gmail-style focused reading flow.",
+        "split": "Split pane",
+        "split_description": "Keep the message list and reading pane visible side by side.",
+        "focus": "Focused list",
+        "focus_description": "Show one line per message and open mail full-width while keeping the folder sidebar visible."
+      },
       "show_preview": {
         "label": "Show Preview Text",
-        "description": "Display email preview in the list"
+        "description": "Display email preview in the list",
+        "focus_description": "Display inline preview text inside the focused one-line message list"
       },
       "disable_threading": {
         "label": "Disable Conversation Grouping",

stores/settings-store.ts

@@ -33,6 +33,7 @@ export type MailAttachmentAction = 'preview' | 'download';
 export type AttachmentPosition = 'beside-sender' | 'below-header';
 export type ToolbarPosition = 'top' | 'below-subject';
 export type ArchiveMode = 'single' | 'year' | 'month';
+export type MailLayout = 'split' | 'focus';
 
 export type HoverAction = 'delete' | 'star' | 'markRead' | 'archive' | 'tag' | 'spam';
 export type HoverActionsMode = 'inline' | 'floating';
@@ -105,6 +106,7 @@ interface SettingsState {
   deleteAction: DeleteAction;
   permanentlyDeleteJunk: boolean; // Permanently delete emails from junk/spam instead of moving to trash
   showPreview: boolean;
+  mailLayout: MailLayout;
   emailsPerPage: number;
   externalContentPolicy: ExternalContentPolicy;
   mailAttachmentAction: MailAttachmentAction;
@@ -225,6 +227,7 @@ const DEFAULT_SETTINGS = {
   deleteAction: 'trash' as DeleteAction,
   permanentlyDeleteJunk: false,
   showPreview: true,
+  mailLayout: 'split' as MailLayout,
   emailsPerPage: 50,
   externalContentPolicy: 'ask' as ExternalContentPolicy,
   mailAttachmentAction: 'preview' as MailAttachmentAction,
@@ -335,6 +338,7 @@ export const useSettingsStore = create<SettingsState>()(
           markAsReadDelay: state.markAsReadDelay,
           deleteAction: state.deleteAction,
           showPreview: state.showPreview,
+          mailLayout: state.mailLayout,
           emailsPerPage: state.emailsPerPage,
           externalContentPolicy: state.externalContentPolicy,
           mailAttachmentAction: state.mailAttachmentAction,