diff --git a/webui/src/App.tsx b/webui/src/App.tsx
index 43729e05b..c7a5e942d 100644
--- a/webui/src/App.tsx
+++ b/webui/src/App.tsx
@@ -2718,7 +2718,6 @@ function Shell({
                 addPaneDisabled={creatingPane || activePaneLimitReached}
                 addPaneDisabledLabel={activePaneLimitReached
                   ? t("workbench.paneLimit", {
-                      defaultValue: "Maximum {{count}} panes",
                       count: MAX_WORKBENCH_PANES,
                     })
                   : undefined}
@@ -2812,7 +2811,6 @@ function Shell({
                       composerPortalTarget={context.composerPortalTarget}
                       composerActive={context.active}
                       composerInputAriaLabel={t("workbench.composerAria", {
-                        defaultValue: "Message {{title}}",
                         title: pane.title,
                       })}
                       emptyComposerVariant="thread"
diff --git a/webui/src/components/ChatList.tsx b/webui/src/components/ChatList.tsx
index 2d178244e..e8d4735ae 100644
--- a/webui/src/components/ChatList.tsx
+++ b/webui/src/components/ChatList.tsx
@@ -1013,9 +1013,7 @@ export const ChatList = memo(function ChatList({
                               {paneGroup && onCreateTab ? (
                                 <DropdownMenuItem onSelect={() => onCreateTab(s.key)}>
                                   <PanelsTopLeft className="h-4 w-4 shrink-0" aria-hidden />
-                                  {t("workbench.createGroup", {
-                                    defaultValue: "Create group",
-                                  })}
+                                  {t("workbench.createGroup")}
                                 </DropdownMenuItem>
                               ) : null}
                               {paneGroup && onAttachPane ? (
@@ -1220,7 +1218,7 @@ function WorkbenchTabHeader({
               {onDissolve ? (
                 <DropdownMenuItem onSelect={onDissolve}>
                   <Ungroup className="h-4 w-4 shrink-0" />
-                  {t("workbench.dissolveTab", { defaultValue: "Dissolve group" })}
+                  {t("workbench.dissolveTab")}
                 </DropdownMenuItem>
               ) : null}
               <DropdownMenuItem
@@ -1229,9 +1227,7 @@ function WorkbenchTabHeader({
                 className="whitespace-nowrap"
               >
                 <Trash2 className="h-4 w-4 shrink-0" />
-                {t("workbench.deleteConversations", {
-                  defaultValue: "Delete all chats",
-                })}
+                {t("workbench.deleteConversations")}
               </DropdownMenuItem>
             </DropdownMenuContent>
           </DropdownMenu>
@@ -1322,10 +1318,7 @@ function ActivePaneRows({
   return (
     <ul
       id={id}
-      aria-label={t("workbench.panesInTab", {
-        defaultValue: "Panes in {{title}}",
-        title: tabTitle,
-      })}
+      aria-label={t("workbench.panesInTab", { title: tabTitle })}
       className="mt-0.5 space-y-0.5 rounded-es-[14px] border-s-2 border-sidebar-foreground/25 pb-1"
     >
       {panes.map((pane) => {
@@ -1335,10 +1328,7 @@ function ActivePaneRows({
           : updated.has(pane.chatId) && !active
             ? "updated"
             : null;
-        const paneActionsLabel = t("workbench.paneActions", {
-          defaultValue: "{{title}} pane actions",
-          title: pane.title,
-        });
+        const paneActionsLabel = t("workbench.paneActions", { title: pane.title });
         const selected = selectedDeleteKeys.has(pane.key);
         const isPinned = pinned.has(pane.key);
         const isArchived = archived.has(pane.key);
@@ -1452,10 +1442,7 @@ function ActivePaneRows({
                   {onDetachPane ? (
                     <DropdownMenuItem onSelect={() => onDetachPane(group.tabKey, pane.key)}>
                       <Unplug className="h-4 w-4 shrink-0" />
-                      {t("workbench.detachPane", {
-                        defaultValue: "Remove",
-                        title: pane.title,
-                      })}
+                      {t("workbench.detachPane", { title: pane.title })}
                     </DropdownMenuItem>
                   ) : null}
                   {onAttachPane ? (
@@ -1521,7 +1508,7 @@ function MoveToGroupSubmenu({
     <DropdownMenuSub>
       <DropdownMenuSubTrigger>
         <MoveRight className="h-4 w-4 shrink-0" aria-hidden />
-        {t("workbench.moveTo", { defaultValue: "Move to" })}
+        {t("workbench.moveTo")}
       </DropdownMenuSubTrigger>
       <DropdownMenuSubContent>
         {targets.map((target) => (
diff --git a/webui/src/i18n/locales/en/common.json b/webui/src/i18n/locales/en/common.json
index b108a01e6..a90a2f0b4 100644
--- a/webui/src/i18n/locales/en/common.json
+++ b/webui/src/i18n/locales/en/common.json
@@ -1451,7 +1451,7 @@
   "workbench": {
     "aria": "Conversation workbench",
     "panes": "Panes",
-    "tabAria": "Tab: {{title}}",
+    "tabAria": "Group: {{title}}",
     "panesInTab": "Panes in {{title}}",
     "collapseTabGroup": "Collapse panes in {{title}}",
     "expandTabGroup": "Expand panes in {{title}}",
diff --git a/webui/src/i18n/locales/es/common.json b/webui/src/i18n/locales/es/common.json
index fd8ab197e..87932c357 100644
--- a/webui/src/i18n/locales/es/common.json
+++ b/webui/src/i18n/locales/es/common.json
@@ -1438,7 +1438,7 @@
   "workbench": {
     "aria": "Área de conversaciones",
     "panes": "Paneles",
-    "tabAria": "Pestaña: {{title}}",
+    "tabAria": "Grupo: {{title}}",
     "panesInTab": "Paneles de {{title}}",
     "collapseTabGroup": "Contraer los paneles de {{title}}",
     "expandTabGroup": "Expandir los paneles de {{title}}",
diff --git a/webui/src/i18n/locales/fr/common.json b/webui/src/i18n/locales/fr/common.json
index 822397e50..d60356ffa 100644
--- a/webui/src/i18n/locales/fr/common.json
+++ b/webui/src/i18n/locales/fr/common.json
@@ -1437,7 +1437,7 @@
   "workbench": {
     "aria": "Espace de conversations",
     "panes": "Volets",
-    "tabAria": "Onglet : {{title}}",
+    "tabAria": "Groupe : {{title}}",
     "panesInTab": "Volets dans {{title}}",
     "collapseTabGroup": "Réduire les volets de {{title}}",
     "expandTabGroup": "Développer les volets de {{title}}",
diff --git a/webui/src/i18n/locales/id/common.json b/webui/src/i18n/locales/id/common.json
index f25a2767f..b2d73b44b 100644
--- a/webui/src/i18n/locales/id/common.json
+++ b/webui/src/i18n/locales/id/common.json
@@ -1437,7 +1437,7 @@
   "workbench": {
     "aria": "Ruang kerja percakapan",
     "panes": "Panel",
-    "tabAria": "Tab: {{title}}",
+    "tabAria": "Grup: {{title}}",
     "panesInTab": "Panel di {{title}}",
     "collapseTabGroup": "Ciutkan panel di {{title}}",
     "expandTabGroup": "Luaskan panel di {{title}}",
diff --git a/webui/src/i18n/locales/ja/common.json b/webui/src/i18n/locales/ja/common.json
index 0b67d35cb..851860d4e 100644
--- a/webui/src/i18n/locales/ja/common.json
+++ b/webui/src/i18n/locales/ja/common.json
@@ -1437,7 +1437,7 @@
   "workbench": {
     "aria": "会話ワークベンチ",
     "panes": "ペイン",
-    "tabAria": "タブ：{{title}}",
+    "tabAria": "グループ：{{title}}",
     "panesInTab": "{{title}} のペイン",
     "collapseTabGroup": "{{title}} のペインを折りたたむ",
     "expandTabGroup": "{{title}} のペインを展開する",
diff --git a/webui/src/i18n/locales/ko/common.json b/webui/src/i18n/locales/ko/common.json
index 88a56346c..7d17a7149 100644
--- a/webui/src/i18n/locales/ko/common.json
+++ b/webui/src/i18n/locales/ko/common.json
@@ -1437,7 +1437,7 @@
   "workbench": {
     "aria": "대화 워크벤치",
     "panes": "창",
-    "tabAria": "탭: {{title}}",
+    "tabAria": "그룹: {{title}}",
     "panesInTab": "{{title}}의 창",
     "collapseTabGroup": "{{title}}의 창 접기",
     "expandTabGroup": "{{title}}의 창 펼치기",
diff --git a/webui/src/i18n/locales/pt-BR/common.json b/webui/src/i18n/locales/pt-BR/common.json
index 9e6bbd0a1..3310e1c0b 100644
--- a/webui/src/i18n/locales/pt-BR/common.json
+++ b/webui/src/i18n/locales/pt-BR/common.json
@@ -1451,7 +1451,7 @@
   "workbench": {
     "aria": "Área de conversas",
     "panes": "Painéis",
-    "tabAria": "Aba: {{title}}",
+    "tabAria": "Grupo: {{title}}",
     "panesInTab": "Painéis em {{title}}",
     "collapseTabGroup": "Recolher os painéis em {{title}}",
     "expandTabGroup": "Expandir os painéis em {{title}}",
diff --git a/webui/src/i18n/locales/vi/common.json b/webui/src/i18n/locales/vi/common.json
index 3bad5d74d..3025ac67a 100644
--- a/webui/src/i18n/locales/vi/common.json
+++ b/webui/src/i18n/locales/vi/common.json
@@ -1437,7 +1437,7 @@
   "workbench": {
     "aria": "Không gian hội thoại",
     "panes": "Khung",
-    "tabAria": "Thẻ: {{title}}",
+    "tabAria": "Nhóm: {{title}}",
     "panesInTab": "Các khung trong {{title}}",
     "collapseTabGroup": "Thu gọn các khung trong {{title}}",
     "expandTabGroup": "Mở rộng các khung trong {{title}}",
diff --git a/webui/src/i18n/locales/zh-CN/common.json b/webui/src/i18n/locales/zh-CN/common.json
index 07c90d081..709b42ccd 100644
--- a/webui/src/i18n/locales/zh-CN/common.json
+++ b/webui/src/i18n/locales/zh-CN/common.json
@@ -1451,7 +1451,7 @@
   "workbench": {
     "aria": "会话工作台",
     "panes": "窗格",
-    "tabAria": "标签页：{{title}}",
+    "tabAria": "分组：{{title}}",
     "panesInTab": "{{title}} 中的窗格",
     "collapseTabGroup": "折叠 {{title}} 中的窗格",
     "expandTabGroup": "展开 {{title}} 中的窗格",
diff --git a/webui/src/i18n/locales/zh-TW/common.json b/webui/src/i18n/locales/zh-TW/common.json
index eef3d8401..9e3763d85 100644
--- a/webui/src/i18n/locales/zh-TW/common.json
+++ b/webui/src/i18n/locales/zh-TW/common.json
@@ -1437,7 +1437,7 @@
   "workbench": {
     "aria": "對話工作台",
     "panes": "窗格",
-    "tabAria": "標籤頁：{{title}}",
+    "tabAria": "群組：{{title}}",
     "panesInTab": "{{title}} 中的窗格",
     "collapseTabGroup": "收合 {{title}} 中的窗格",
     "expandTabGroup": "展開 {{title}} 中的窗格",
diff --git a/webui/src/tests/app-layout.test.tsx b/webui/src/tests/app-layout.test.tsx
index adb863655..0bba2d149 100644
--- a/webui/src/tests/app-layout.test.tsx
+++ b/webui/src/tests/app-layout.test.tsx
@@ -3099,7 +3099,7 @@ describe("App layout", () => {
 
     await waitFor(() => expect(connectSpy).toHaveBeenCalled());
     const sidebar = screen.getByRole("navigation", { name: "Sidebar navigation" });
-    const alphaTab = await within(sidebar).findByRole("button", { name: "Tab: Alpha tab" });
+    const alphaTab = await within(sidebar).findByRole("button", { name: "Group: Alpha tab" });
     const betaTab = within(sidebar).getByRole("button", { name: "Beta tab" });
     expect(alphaTab.compareDocumentPosition(betaTab) & Node.DOCUMENT_POSITION_FOLLOWING)
       .toBeTruthy();
@@ -3218,7 +3218,7 @@ describe("App layout", () => {
       statusHandlers.forEach((handler) => handler("open"));
     });
     const sidebar = screen.getByRole("navigation", { name: "Sidebar navigation" });
-    expect(within(sidebar).queryByRole("button", { name: "Tab: Solo pane" }))
+    expect(within(sidebar).queryByRole("button", { name: "Group: Solo pane" }))
       .not.toBeInTheDocument();
     setSidebarStateSpy.mockClear();
 
@@ -3228,14 +3228,14 @@ describe("App layout", () => {
     fireEvent.click(await screen.findByRole("menuitem", { name: "Create group" }));
 
     const tabButton = await within(sidebar).findByRole("button", {
-      name: "Tab: Solo pane",
+      name: "Group: Solo pane",
     });
     const tabGroup = tabButton.closest("[data-sidebar-tab-group]") as HTMLElement;
     expect(within(tabGroup).getByRole("list", { name: "Panes in Solo pane" }))
       .toBeInTheDocument();
     expect(within(tabGroup).getAllByRole("button", { name: "Solo pane" }))
       .toHaveLength(1);
-    expect(within(sidebar).queryByRole("button", { name: "Tab: Other pane" }))
+    expect(within(sidebar).queryByRole("button", { name: "Group: Other pane" }))
       .not.toBeInTheDocument();
     await waitFor(() => expect(setSidebarStateSpy).toHaveBeenCalledWith(
       expect.objectContaining({
@@ -3312,7 +3312,7 @@ describe("App layout", () => {
     render(<App />);
     await waitFor(() => expect(connectSpy).toHaveBeenCalled());
     const secondSidebar = screen.getByRole("navigation", { name: "Sidebar navigation" });
-    expect(await within(secondSidebar).findByRole("button", { name: "Tab: Solo pane" }))
+    expect(await within(secondSidebar).findByRole("button", { name: "Group: Solo pane" }))
       .toBeInTheDocument();
   });
 
diff --git a/webui/src/tests/chat-list.test.tsx b/webui/src/tests/chat-list.test.tsx
index e19afae86..54f561eef 100644
--- a/webui/src/tests/chat-list.test.tsx
+++ b/webui/src/tests/chat-list.test.tsx
@@ -90,7 +90,7 @@ describe("ChatList", () => {
       />,
     );
 
-    expect(screen.getByRole("button", { name: "Tab: Root topic" }))
+    expect(screen.getByRole("button", { name: "Group: Root topic" }))
       .toHaveAttribute("draggable", "false");
     const pane = screen.getByRole("button", { name: "Research pane" });
     expect(pane).toHaveAttribute("draggable", "true");
@@ -209,7 +209,7 @@ describe("ChatList", () => {
       />,
     );
 
-    expect(screen.queryByRole("button", { name: "Tab: Solo pane" }))
+    expect(screen.queryByRole("button", { name: "Group: Solo pane" }))
       .not.toBeInTheDocument();
     expect(screen.getAllByText("Solo pane")).toHaveLength(1);
     expect(screen.queryByRole("list", { name: "Panes in Solo pane" }))
@@ -293,10 +293,10 @@ describe("ChatList", () => {
       types: [SESSION_DRAG_TYPE],
     } as unknown as DataTransfer;
     const source = screen.getByRole("button", { name: "Solo topic" });
-    const targetGroup = screen.getByRole("button", { name: "Tab: Target group" })
+    const targetGroup = screen.getByRole("button", { name: "Group: Target group" })
       .closest("[data-sidebar-tab-group]")!;
     const targetSurface = targetGroup.querySelector("[data-workbench-tab-surface]")!;
-    const fullGroup = screen.getByRole("button", { name: "Tab: Full group" })
+    const fullGroup = screen.getByRole("button", { name: "Group: Full group" })
       .closest("[data-sidebar-tab-group]")!;
     const fullSurface = fullGroup.querySelector("[data-workbench-tab-surface]")!;
 
@@ -367,7 +367,7 @@ describe("ChatList", () => {
       types: [SESSION_DRAG_TYPE],
     } as unknown as DataTransfer;
     const source = screen.getByRole("button", { name: "Research pane" });
-    const sourceSurface = screen.getByRole("button", { name: "Tab: Root topic" })
+    const sourceSurface = screen.getByRole("button", { name: "Group: Root topic" })
       .closest("[data-workbench-tab-surface]")!;
     const standaloneList = document.querySelector("[data-chat-list-content]")!;
 
@@ -443,7 +443,7 @@ describe("ChatList", () => {
     expect(child.closest("[data-sidebar-pane]"))
       .toHaveAttribute("data-sidebar-pane", "websocket:child");
     expect(child).toHaveAttribute("aria-current", "true");
-    const targetTabRow = screen.getByRole("button", { name: "Tab: Target tab" })
+    const targetTabRow = screen.getByRole("button", { name: "Group: Target tab" })
       .closest("li")!;
     const targetChild = within(targetTabRow).getByRole("button", {
       name: "Target research",
@@ -464,7 +464,7 @@ describe("ChatList", () => {
     expect(onSelect).not.toHaveBeenCalled();
 
     onSelectPane.mockClear();
-    const rootTab = screen.getByRole("button", { name: "Tab: Root topic" });
+    const rootTab = screen.getByRole("button", { name: "Group: Root topic" });
     fireEvent.click(rootTab);
     expect(onSelectPane).not.toHaveBeenCalled();
     expect(onSelect).not.toHaveBeenCalled();
@@ -510,7 +510,7 @@ describe("ChatList", () => {
     fireEvent.keyDown(document, { key: "Escape" });
 
     expect(child).toHaveAttribute("draggable", "false");
-    expect(screen.getByRole("button", { name: "Tab: Target tab" }))
+    expect(screen.getByRole("button", { name: "Group: Target tab" }))
       .toHaveAttribute("draggable", "false");
   });
 
@@ -547,7 +547,7 @@ describe("ChatList", () => {
       />,
     );
 
-    const tabButton = screen.getByRole("button", { name: "Tab: Root topic" });
+    const tabButton = screen.getByRole("button", { name: "Group: Root topic" });
     const tabGroup = tabButton.closest("[data-sidebar-tab-group]")!;
     const tabHeader = tabButton.closest("[data-workbench-tab]")!;
     const tabSurface = tabButton.closest("[data-workbench-tab-surface]")!;
@@ -587,7 +587,7 @@ describe("ChatList", () => {
     expect(within(tabGroup).getByRole("button", {
       name: "Expand panes in Root topic",
     })).toHaveAttribute("aria-expanded", "false");
-    expect(within(tabGroup).getByRole("button", { name: "Tab: Root topic" }))
+    expect(within(tabGroup).getByRole("button", { name: "Group: Root topic" }))
       .not.toHaveAttribute("aria-current");
 
     fireEvent.click(within(tabGroup).getByRole("button", {
@@ -634,8 +634,8 @@ describe("ChatList", () => {
     fireEvent.click(await screen.findByRole("menuitem", { name: "Select" }));
 
     expect(screen.getByText("1 selected")).toBeInTheDocument();
-    fireEvent.click(screen.getByRole("button", { name: "Tab: Root topic" }));
-    expect(screen.getByRole("button", { name: "Tab: Root topic" }))
+    fireEvent.click(screen.getByRole("button", { name: "Group: Root topic" }));
+    expect(screen.getByRole("button", { name: "Group: Root topic" }))
       .toHaveAttribute("aria-pressed", "true");
     expect(screen.getByRole("button", { name: "Root topic" }))
       .toHaveAttribute("aria-pressed", "true");
@@ -942,12 +942,12 @@ describe("ChatList", () => {
     };
     const firstRender = render(<ChatList {...props} />);
 
-    fireEvent.click(screen.getByRole("button", { name: "Tab: Root topic" }));
+    fireEvent.click(screen.getByRole("button", { name: "Group: Root topic" }));
     expect(screen.queryByRole("button", { name: "Research pane" })).not.toBeInTheDocument();
     firstRender.unmount();
 
     render(<ChatList {...props} />);
-    expect(screen.getByRole("button", { name: "Tab: Root topic" }))
+    expect(screen.getByRole("button", { name: "Group: Root topic" }))
       .toHaveAttribute("aria-expanded", "false");
     expect(screen.queryByRole("button", { name: "Research pane" })).not.toBeInTheDocument();
   });
diff --git a/webui/src/tests/i18n.test.tsx b/webui/src/tests/i18n.test.tsx
index b3b5a68a5..2891cbd97 100644
--- a/webui/src/tests/i18n.test.tsx
+++ b/webui/src/tests/i18n.test.tsx
@@ -269,6 +269,22 @@ const LOCALIZED_NEW_SURFACE_KEYS = [
   "chat.groups.yesterday",
   "chat.groups.earlier",
   "chat.groups.archived",
+  "workbench.tabAria",
+  "workbench.panesInTab",
+  "workbench.collapseTabGroup",
+  "workbench.expandTabGroup",
+  "workbench.dropPane",
+  "workbench.createGroup",
+  "workbench.moveTo",
+  "workbench.renameGroupTitle",
+  "workbench.renameGroupDescription",
+  "workbench.renameGroupPlaceholder",
+  "workbench.dissolveTab",
+  "workbench.deleteConversations",
+  "workbench.paneLimit",
+  "workbench.paneActions",
+  "workbench.detachPane",
+  "workbench.composerAria",
   "thread.promptNavigator.railAria",
   "thread.composer.mentions.cliTitle",
   "thread.composer.mentions.mcpTitle",
@@ -582,6 +598,18 @@ describe("webui i18n", () => {
     expect(settings.skills.marketplaceTrendingTitle).toBe("各市场热门技能");
   });
 
+  it("keeps the Simplified Chinese group workflow localized", () => {
+    const workbench = resources["zh-CN"].common.workbench;
+
+    expect(workbench.tabAria).toBe("分组：{{title}}");
+    expect(workbench.createGroup).toBe("创建分组");
+    expect(workbench.renameGroupTitle).toBe("重命名分组");
+    expect(workbench.renameGroupDescription).toBe("为这个分组命名。");
+    expect(workbench.renameGroupPlaceholder).toBe("分组名称");
+    expect(workbench.moveTo).toBe("移动到");
+    expect(workbench.detachPane).toBe("移出");
+  });
+
   it("keeps Indonesian and Vietnamese settings free of copied Spanish help text", () => {
     const spanish = flattenResource(resources.es.common);