refactor(desktop): move trace entry into Settings

Trace is a low-frequency diagnostic feature, so its entry points no
longer sit in primary chrome:

- Remove the Trace nav item above the session list in the sidebar
- Remove the trace open/open-window buttons from the session header
- Add a Trace tab in Settings between Token usage and Diagnostics,
  embedding the existing TraceList page full-bleed
- Add settings.tab.trace and drop unused sidebar.traces across locales

desktop/src/__tests__/generalSettings.test.tsx

@@ -94,6 +94,10 @@ vi.mock('../pages/ActivitySettings', () => ({
   ActivitySettings: () => <div>Activity Settings Mock</div>,
 }))
 
+vi.mock('../pages/TraceList', () => ({
+  TraceList: () => <div>Trace List Mock</div>,
+}))
+
 vi.mock('../stores/agentStore', () => ({
   useAgentStore: () => ({
     activeAgents: [],
@@ -677,6 +681,20 @@ describe('Settings > General tab', () => {
     expect(screen.getByText('Activity Settings Mock')).toBeInTheDocument()
   })
 
+  it('opens the Trace tab from Settings navigation between Token usage and Diagnostics', () => {
+    render(<Settings />)
+
+    const usageTab = screen.getByText('Token usage')
+    const traceTab = screen.getByText('Trace')
+    const diagnosticsTab = screen.getByText('Diagnostics')
+    expect((usageTab.compareDocumentPosition(traceTab) & Node.DOCUMENT_POSITION_FOLLOWING) !== 0).toBe(true)
+    expect((traceTab.compareDocumentPosition(diagnosticsTab) & Node.DOCUMENT_POSITION_FOLLOWING) !== 0).toBe(true)
+
+    fireEvent.click(traceTab)
+
+    expect(screen.getByText('Trace List Mock')).toBeInTheDocument()
+  })
+
   it('lets the user disable WebFetch preflight skipping', () => {
     render(<Settings />)
 

desktop/src/components/layout/Sidebar.tsx

@@ -5,7 +5,7 @@ import { useUIStore } from '../../stores/uiStore'
 import { useTranslation, type TranslationKey } from '../../i18n'
 import { ConfirmDialog } from '../shared/ConfirmDialog'
 import type { SessionListItem } from '../../types/session'
-import { useTabStore, SETTINGS_TAB_ID, SCHEDULED_TAB_ID, TRACE_LIST_TAB_ID } from '../../stores/tabStore'
+import { useTabStore, SETTINGS_TAB_ID, SCHEDULED_TAB_ID } from '../../stores/tabStore'
 import { useChatStore } from '../../stores/chatStore'
 import { useOpenTargetStore } from '../../stores/openTargetStore'
 import { desktopUiPreferencesApi, type SidebarProjectPreferences } from '../../api/desktopUiPreferences'
@@ -686,21 +686,6 @@ export function Sidebar({ isMobile = false, onRequestClose }: SidebarProps) {
             {t('sidebar.scheduled')}
           </NavItem>
         )}
-        {!isMobile && (
-          <NavItem
-            active={activeTabId === TRACE_LIST_TAB_ID}
-            collapsed={!expanded}
-            label={t('sidebar.traces')}
-            touchFriendly={isMobile}
-            onClick={() => {
-              useTabStore.getState().openTracesTab(t('sidebar.traces'))
-              closeMobileDrawer()
-            }}
-            icon={<span className="material-symbols-outlined text-[18px]">account_tree</span>}
-          >
-            {t('sidebar.traces')}
-          </NavItem>
-        )}
       </div>
 
       {expanded ? (

desktop/src/i18n/locales/en.ts

@@ -21,7 +21,6 @@ export const en = {
   // ─── Sidebar ──────────────────────────────────────
   'sidebar.newSession': 'New session',
   'sidebar.scheduled': 'Scheduled',
-  'sidebar.traces': 'Trace',
   'sidebar.terminal': 'Terminal',
   'sidebar.settings': 'Settings',
   'sidebar.searchPlaceholder': 'Search sessions...',
@@ -171,6 +170,7 @@ export const en = {
   'settings.tab.providers': 'Providers',
   'settings.tab.permissions': 'Permissions',
   'settings.tab.activity': 'Token usage',
+  'settings.tab.trace': 'Trace',
   'settings.tab.general': 'General',
   'settings.tab.h5Access': 'H5 Access',
   'settings.tab.terminal': 'Terminal',

desktop/src/i18n/locales/jp.ts

@@ -23,7 +23,6 @@ export const jp: Record<TranslationKey, string> = {
   // ─── Sidebar ──────────────────────────────────────
   'sidebar.newSession': '新しいセッション',
   'sidebar.scheduled': 'スケジュール',
-  'sidebar.traces': 'Trace',
   'sidebar.terminal': 'ターミナル',
   'sidebar.settings': '設定',
   'sidebar.searchPlaceholder': 'セッションを検索...',
@@ -173,6 +172,7 @@ export const jp: Record<TranslationKey, string> = {
   'settings.tab.providers': 'プロバイダー',
   'settings.tab.permissions': '権限',
   'settings.tab.activity': 'トークン使用量',
+  'settings.tab.trace': 'Trace',
   'settings.tab.general': '一般',
   'settings.tab.h5Access': 'H5 アクセス',
   'settings.tab.terminal': 'ターミナル',

desktop/src/i18n/locales/kr.ts

@@ -23,7 +23,6 @@ export const kr: Record<TranslationKey, string> = {
   // ─── Sidebar ──────────────────────────────────────
   'sidebar.newSession': '새 세션',
   'sidebar.scheduled': '예약 작업',
-  'sidebar.traces': 'Trace',
   'sidebar.terminal': '터미널',
   'sidebar.settings': '설정',
   'sidebar.searchPlaceholder': '세션 검색...',
@@ -173,6 +172,7 @@ export const kr: Record<TranslationKey, string> = {
   'settings.tab.providers': '공급자',
   'settings.tab.permissions': '권한',
   'settings.tab.activity': '토큰 사용량',
+  'settings.tab.trace': 'Trace',
   'settings.tab.general': '일반',
   'settings.tab.h5Access': 'H5 액세스',
   'settings.tab.terminal': '터미널',

desktop/src/i18n/locales/zh-TW.ts

@@ -23,7 +23,6 @@ export const zh: Record<TranslationKey, string> = {
   // ─── Sidebar ──────────────────────────────────────
   'sidebar.newSession': '新建會話',
   'sidebar.scheduled': '定時任務',
-  'sidebar.traces': 'Trace',
   'sidebar.terminal': '終端',
   'sidebar.settings': '設定',
   'sidebar.searchPlaceholder': '搜尋會話...',
@@ -173,6 +172,7 @@ export const zh: Record<TranslationKey, string> = {
   'settings.tab.providers': '服務商',
   'settings.tab.permissions': '許可權',
   'settings.tab.activity': 'Token 用量',
+  'settings.tab.trace': 'Trace',
   'settings.tab.general': '通用',
   'settings.tab.h5Access': 'H5 訪問',
   'settings.tab.terminal': '終端',

desktop/src/i18n/locales/zh.ts

@@ -23,7 +23,6 @@ export const zh: Record<TranslationKey, string> = {
   // ─── Sidebar ──────────────────────────────────────
   'sidebar.newSession': '新建会话',
   'sidebar.scheduled': '定时任务',
-  'sidebar.traces': 'Trace',
   'sidebar.terminal': '终端',
   'sidebar.settings': '设置',
   'sidebar.searchPlaceholder': '搜索会话...',
@@ -173,6 +172,7 @@ export const zh: Record<TranslationKey, string> = {
   'settings.tab.providers': '服务商',
   'settings.tab.permissions': '权限',
   'settings.tab.activity': 'Token 用量',
+  'settings.tab.trace': 'Trace',
   'settings.tab.general': '通用',
   'settings.tab.h5Access': 'H5 访问',
   'settings.tab.terminal': '终端',

desktop/src/pages/ActiveSession.test.tsx

@@ -186,67 +186,6 @@ describe('ActiveSession task polling', () => {
     expect(screen.getByTestId('chat-input')).toHaveAttribute('data-variant', 'default')
   })
 
-  it('opens the current session trace in a separate live window', () => {
-    const sessionId = 'trace-window-session'
-    const openSpy = vi.spyOn(window, 'open').mockImplementation(() => null)
-
-    useSessionStore.setState({
-      sessions: [{
-        id: sessionId,
-        title: 'Trace Window Session',
-        createdAt: '2026-05-07T00:00:00.000Z',
-        modifiedAt: '2026-05-07T00:00:00.000Z',
-        messageCount: 1,
-        projectPath: '/workspace/project',
-        workDir: '/workspace/project',
-        workDirExists: true,
-      }],
-      activeSessionId: sessionId,
-      isLoading: false,
-      error: null,
-    })
-    useTabStore.setState({
-      tabs: [{ sessionId, title: 'Trace Window Session', type: 'session', status: 'idle' }],
-      activeTabId: sessionId,
-    })
-    useChatStore.setState({
-      sessions: {
-        [sessionId]: {
-          messages: [{ id: 'msg-1', type: 'assistant_text', content: 'hello', timestamp: 1 }],
-          chatState: 'idle',
-          connectionState: 'connected',
-          streamingText: '',
-          streamingToolInput: '',
-          activeToolUseId: null,
-          activeToolName: null,
-          activeThinkingId: null,
-          pendingPermission: null,
-          pendingComputerUsePermission: null,
-          tokenUsage: { input_tokens: 0, output_tokens: 0 },
-          elapsedSeconds: 0,
-          statusVerb: '',
-          slashCommands: [],
-          agentTaskNotifications: {},
-          elapsedTimer: null,
-        },
-      },
-    })
-
-    try {
-      render(<ActiveSession />)
-      fireEvent.click(screen.getByLabelText(/独立|separate/i))
-
-      expect(openSpy).toHaveBeenCalledWith(
-        expect.stringContaining(`traceSessionId=${sessionId}`),
-        '_blank',
-        'noopener,noreferrer',
-      )
-      expect(openSpy.mock.calls[0]?.[0]).toContain('traceWindow=1')
-    } finally {
-      openSpy.mockRestore()
-    }
-  })
-
   it('renders the current goal as a lightweight header strip without a page-level panel', () => {
     const sessionId = 'goal-visible-session'
 

desktop/src/pages/ActiveSession.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useMemo, useRef, useState } from 'react'
-import { ExternalLink, RadioTower, Target } from 'lucide-react'
+import { Target } from 'lucide-react'
 import {
   SCHEDULED_TAB_ID,
   SETTINGS_TAB_ID,
@@ -32,8 +32,6 @@ import type { ActiveGoalState } from '../types/chat'
 import { useMobileViewport } from '../hooks/useMobileViewport'
 import { isDesktopRuntime } from '../lib/desktopRuntime'
 import { publicAssetPath } from '../lib/publicAsset'
-import { getDesktopHost } from '../lib/desktopHost'
-import { buildTraceWindowUrl } from '../lib/traceLaunch'
 
 const TASK_POLL_INTERVAL_MS = 1000
 const WORKSPACE_RESIZE_STEP = 32
@@ -364,22 +362,6 @@ export function ActiveSession() {
     return t('session.timeDays', { n: Math.floor(diff / 86400000) })
   }, [session?.modifiedAt, t])
 
-  const openTrace = () => {
-    if (!activeTabId) return
-    const title = session?.title || t('session.untitled')
-    useTabStore.getState().openTraceTab(activeTabId, `${t('trace.title')}: ${title}`)
-  }
-
-  const openTraceWindow = () => {
-    if (!activeTabId) return
-    const host = getDesktopHost()
-    if (host.trace) {
-      void host.trace.openWindow(activeTabId)
-      return
-    }
-    window.open(buildTraceWindowUrl(activeTabId), '_blank', 'noopener,noreferrer')
-  }
-
   if (!activeTabId) return null
 
   return (
@@ -480,25 +462,6 @@ export function ActiveSession() {
                       >
                         {session?.title || t('session.untitled')}
                       </h1>
-                      <button
-                        type="button"
-                        aria-label={t('trace.open')}
-                        title={t('trace.open')}
-                        onClick={openTrace}
-                        className="inline-flex h-8 shrink-0 items-center gap-1.5 rounded-[8px] border border-[var(--color-border)] px-2.5 text-xs font-semibold text-[var(--color-text-secondary)] transition-colors hover:border-[var(--color-border-focus)] hover:text-[var(--color-text-primary)] active:scale-[0.98]"
-                      >
-                        <RadioTower size={14} strokeWidth={2} aria-hidden="true" />
-                        <span className={showRightPanel ? 'sr-only' : 'hidden sm:inline'}>{t('trace.open')}</span>
-                      </button>
-                      <button
-                        type="button"
-                        aria-label={t('trace.openWindow')}
-                        title={t('trace.openWindow')}
-                        onClick={openTraceWindow}
-                        className="inline-flex h-8 w-8 shrink-0 items-center justify-center rounded-[8px] border border-[var(--color-border)] text-[var(--color-text-secondary)] transition-colors hover:border-[var(--color-border-focus)] hover:text-[var(--color-text-primary)] active:scale-[0.98]"
-                      >
-                        <ExternalLink size={14} strokeWidth={2} aria-hidden="true" />
-                      </button>
                     </div>
                     <div
                       className={

desktop/src/pages/Settings.tsx

@@ -28,6 +28,7 @@ import { ComputerUseSettings } from './ComputerUseSettings'
 import { McpSettings } from './McpSettings'
 import { TerminalSettings } from './TerminalSettings'
 import { DiagnosticsSettings } from './DiagnosticsSettings'
+import { TraceList } from './TraceList'
 import { ActivitySettings } from './ActivitySettings'
 import { MemorySettings } from './MemorySettings'
 import { useUIStore, type SettingsTab } from '../stores/uiStore'
@@ -166,6 +167,7 @@ export function Settings() {
             <TabButton icon="extension" label={t('settings.tab.plugins')} active={activeTab === 'plugins'} onClick={() => setActiveTab('plugins')} />
             <TabButton icon="mouse" label={t('settings.tab.computerUse')} active={activeTab === 'computerUse'} onClick={() => setActiveTab('computerUse')} />
             <TabButton icon="monitoring" label={t('settings.tab.activity')} active={activeTab === 'activity'} onClick={() => setActiveTab('activity')} />
+            <TabButton icon="account_tree" label={t('settings.tab.trace')} active={activeTab === 'trace'} onClick={() => setActiveTab('trace')} />
             <TabButton icon="monitor_heart" label={t('settings.tab.diagnostics')} active={activeTab === 'diagnostics'} onClick={() => setActiveTab('diagnostics')} />
           </div>
           <div className="border-t border-[var(--color-border)]/40 pt-1">
@@ -173,8 +175,8 @@ export function Settings() {
           </div>
         </div>
 
-        {/* Tab content */}
+        {/* Tab content; trace embeds a full-bleed page that manages its own scroll */}
-        <div className="flex-1 overflow-y-auto px-8 py-6">
+        <div className={activeTab === 'trace' ? 'flex-1 flex min-h-0 flex-col overflow-hidden' : 'flex-1 overflow-y-auto px-8 py-6'}>
           {activeTab === 'providers' && <ProviderSettings />}
           {activeTab === 'activity' && <ActivitySettings />}
           {activeTab === 'general' && <GeneralSettings />}
@@ -187,6 +189,7 @@ export function Settings() {
           {activeTab === 'memory' && <MemorySettings />}
           {activeTab === 'plugins' && <PluginSettings />}
           {activeTab === 'computerUse' && <ComputerUseSettings />}
+          {activeTab === 'trace' && <TraceList />}
           {activeTab === 'diagnostics' && <DiagnosticsSettings />}
           {activeTab === 'about' && <AboutSettings />}
         </div>

desktop/src/stores/uiStore.ts

@@ -41,6 +41,7 @@ export type SettingsTab =
   | 'memory'
   | 'plugins'
   | 'computerUse'
+  | 'trace'
   | 'diagnostics'
   | 'about'