fix: sync tab and pane titles when reopening renamed sessions from sidebar

src/components/HistoryView.tsx

@@ -127,6 +127,7 @@ export default function HistoryView({ onOpenSession }: { onOpenSession?: () => v
       firstUserMessage: session.firstUserMessage,
       isSubagent: session.isSubagent,
       isNonInteractive: session.isNonInteractive,
+      hasTitle: !!session.title,
     }))
     onOpenSession?.()
   }

src/components/Sidebar.tsx

@@ -7,7 +7,7 @@ import { Tooltip, TooltipTrigger, TooltipContent } from '@/components/ui/tooltip
 import { useAppDispatch, useAppSelector, useAppStore } from '@/store/hooks'
 import { shallowEqual } from 'react-redux'
 import { addTab, openSessionTab, setActiveTab, updateTab } from '@/store/tabsSlice'
-import { addPane, initLayout, setActivePane } from '@/store/panesSlice'
+import { addPane, initLayout, setActivePane, updatePaneTitle } from '@/store/panesSlice'
 import { findPaneForSession } from '@/lib/session-utils'
 import { resolveSessionTypeConfig, buildResumeContent } from '@/lib/session-type-utils'
 import { getAgentChatProviderConfig } from '@/lib/agent-chat-utils'
@@ -377,6 +377,13 @@ export default function Sidebar({
       localServerInstanceId,
     )
     if (existing) {
+      const existingTab = state.tabs.tabs.find((t) => t.id === existing.tabId)
+      if (existingTab && item.title && item.hasTitle && item.title !== existingTab.title && !existingTab.titleSetByUser) {
+        dispatch(updateTab({ id: existingTab.id, updates: { title: item.title } }))
+      }
+      if (existing.paneId && item.hasTitle && item.title) {
+        dispatch(updatePaneTitle({ tabId: existing.tabId, paneId: existing.paneId, title: item.title, setByUser: false }))
+      }
       dispatch(setActiveTab(existing.tabId))
       if (existing.paneId) {
         dispatch(setActivePane({ tabId: existing.tabId, paneId: existing.paneId }))
@@ -406,6 +413,7 @@ export default function Sidebar({
         firstUserMessage: item.firstUserMessage,
         isSubagent: item.isSubagent,
         isNonInteractive: item.isNonInteractive,
+        hasTitle: item.hasTitle,
       }))
       onNavigate('terminal')
       return
@@ -424,6 +432,7 @@ export default function Sidebar({
         firstUserMessage: item.firstUserMessage,
         isSubagent: item.isSubagent,
         isNonInteractive: item.isNonInteractive,
+        hasTitle: item.hasTitle,
       }))
       onNavigate('terminal')
       return

src/components/context-menu/ContextMenuProvider.tsx

@@ -380,6 +380,7 @@ export function ContextMenuProvider({
       firstUserMessage: session.firstUserMessage,
       isSubagent: session.isSubagent,
       isNonInteractive: session.isNonInteractive,
+      hasTitle: !!session.title,
     }))
   }, [dispatch, getSessionInfo, menuState?.target])
 
@@ -605,6 +606,7 @@ export function ContextMenuProvider({
               isSubagent: session.isSubagent,
               isNonInteractive: session.isNonInteractive,
               forceNew: true,
+              hasTitle: !!session.title,
             }))
           }
         }

src/store/selectors/sidebarSelectors.ts

@@ -201,7 +201,6 @@ export function buildSessionItems(
       const fallbackTitle = input.title?.trim()
       if (!existing.hasTitle && fallbackTitle) {
         existing.title = fallbackTitle
-        existing.hasTitle = true
       }
       const fallbackSessionType = input.metadata?.sessionType || input.sessionType
       if (fallbackSessionType && (!existing.sessionType || existing.sessionType === existing.provider)) {
@@ -232,7 +231,7 @@ export function buildSessionItems(
       provider: input.provider,
       sessionType: input.metadata?.sessionType || input.sessionType,
       title: fallbackTitle,
-      hasTitle: fallbackTitle !== input.sessionId.slice(0, 8),
+      hasTitle: false,
       subtitle: input.cwd ? getProjectName(input.cwd) : undefined,
       projectPath: input.cwd,
       timestamp: input.timestamp ?? 0,

src/store/tabsSlice.ts

@@ -1,7 +1,7 @@
 import { createSlice, PayloadAction, createAsyncThunk } from '@reduxjs/toolkit'
 import type { Tab, TerminalStatus, TabMode, ShellType, CodingCliProviderName } from './types'
 import { nanoid } from 'nanoid'
-import { closePane, initLayout, restoreLayout, removeLayout, updatePaneContent } from './panesSlice'
+import { closePane, initLayout, restoreLayout, removeLayout, updatePaneContent, updatePaneTitleByTerminalId, updatePaneTitle } from './panesSlice'
 import { clearTabAttention, clearPaneAttention } from './turnCompletionSlice.js'
 import type { PaneNode } from './paneTypes'
 import { findTabIdForSession } from '@/lib/session-utils'
@@ -524,7 +524,7 @@ export const reopenClosedTab = createAsyncThunk(
 export const openSessionTab = createAsyncThunk(
   'tabs/openSessionTab',
   async (
-    { sessionId, title, cwd, provider, sessionType, terminalId, forceNew, firstUserMessage, isSubagent, isNonInteractive }: {
+    { sessionId, title, cwd, provider, sessionType, terminalId, forceNew, firstUserMessage, isSubagent, isNonInteractive, hasTitle }: {
       sessionId: string
       title?: string
       cwd?: string
@@ -535,6 +535,8 @@ export const openSessionTab = createAsyncThunk(
       firstUserMessage?: string
       isSubagent?: boolean
       isNonInteractive?: boolean
+      /** Only sync title into an existing tab when the session title is a real rename (not a synthesized fallback). */
+      hasTitle?: boolean
     },
     { dispatch, getState }
   ) => {
@@ -762,6 +764,12 @@ export const openSessionTab = createAsyncThunk(
           : undefined
         if (existingTab) {
           updateExistingTabMetadata(existingTab)
+          if (title && hasTitle && title !== existingTab.title && !existingTab.titleSetByUser) {
+            dispatch(updateTab({ id: existingTab.id, updates: { title } }))
+          }
+          if (hasTitle && title) {
+            dispatch(updatePaneTitleByTerminalId({ terminalId, title, setByUser: false }))
+          }
           dispatch(setActiveTab(existingTab.id))
           return
         }
@@ -809,6 +817,36 @@ export const openSessionTab = createAsyncThunk(
         const selectedExistingTabId = existingTabId ?? tabToOpen.id
         const usingStaleSinglePaneFallback = !existingTabId && staleSinglePaneFallbackTab?.id === tabToOpen.id
         updateExistingTabMetadata(tabToOpen)
+        if (title && hasTitle && title !== tabToOpen.title && !tabToOpen.titleSetByUser) {
+          dispatch(updateTab({ id: tabToOpen.id, updates: { title } }))
+        }
+        if (hasTitle && title) {
+          const layout = state.panes.layouts[selectedExistingTabId]
+          if (layout) {
+            const syncPaneTitles = (node: PaneNode) => {
+              if (node.type === 'leaf') {
+                const content = node.content
+                const sessionRef = (content as { sessionRef?: { provider?: unknown; sessionId?: unknown } }).sessionRef
+                const matchesExplicitRef =
+                  typeof sessionRef?.provider === 'string'
+                  && typeof sessionRef?.sessionId === 'string'
+                  && sessionRef.provider === resolvedProvider
+                  && sessionRef.sessionId === sessionId
+                const matchesImplicitRef = (
+                  (content.kind === 'terminal' && content.mode === resolvedProvider && content.resumeSessionId === sessionId) ||
+                  (content.kind === 'agent-chat' && resolvedProvider === 'claude' && content.resumeSessionId === sessionId)
+                )
+                if (matchesExplicitRef || matchesImplicitRef) {
+                  dispatch(updatePaneTitle({ tabId: selectedExistingTabId, paneId: node.id, title, setByUser: false }))
+                }
+                return
+              }
+              syncPaneTitles(node.children[0])
+              syncPaneTitles(node.children[1])
+            }
+            syncPaneTitles(layout)
+          }
+        }
         repairExistingTabLayout(tabToOpen, {
           tabFallbackMissingPaneLocator: usingStaleSinglePaneFallback,
         })

test/e2e/sidebar-click-opens-pane.test.tsx

@@ -448,6 +448,132 @@ describe('sidebar click opens pane (e2e)', () => {
     expect(state.panes.layouts['tab-2'].type).toBe('leaf')
   })
 
+  it('syncs tab and pane title when clicking a renamed session already open in a pane', async () => {
+    const targetId = sessionId('renamed-session')
+
+    const projects: ProjectGroup[] = [
+      {
+        projectPath: '/home/user/project',
+        sessions: [
+          {
+            sessionId: targetId,
+            projectPath: '/home/user/project',
+            lastActivityAt: Date.now(),
+            title: 'Renamed beside name',
+            cwd: '/home/user/project',
+          },
+        ],
+      },
+    ]
+
+    const store = createStore({
+      projects,
+      tabs: [
+        { id: 'tab-1', mode: 'shell' },
+        { id: 'tab-2', mode: 'claude', title: 'Stale Title' },
+      ],
+      activeTabId: 'tab-1',
+      panes: {
+        layouts: {
+          'tab-1': {
+            type: 'leaf',
+            id: 'pane-1',
+            content: { kind: 'terminal', mode: 'shell', createRequestId: 'req-1', status: 'running' },
+          },
+          'tab-2': {
+            type: 'leaf',
+            id: 'pane-2',
+            content: {
+              kind: 'terminal', mode: 'claude', createRequestId: 'req-2', status: 'running',
+              resumeSessionId: targetId,
+            },
+          },
+        },
+        activePane: { 'tab-1': 'pane-1', 'tab-2': 'pane-2' },
+        paneTitles: {},
+      },
+    })
+
+    // Set a stale pane title to test it also gets synced
+    store.dispatch({ type: 'panes/updatePaneTitle', payload: { tabId: 'tab-2', paneId: 'pane-2', title: 'Old Pane Name', setByUser: false } })
+
+    renderSidebar(store)
+
+    await act(async () => {
+      vi.advanceTimersByTime(100)
+    })
+
+    const sessionButton = screen.getByText('Renamed beside name').closest('button')
+    fireEvent.click(sessionButton!)
+
+    const state = store.getState()
+
+    // Should focus the existing tab
+    expect(state.tabs.activeTabId).toBe('tab-2')
+    // Tab title should be updated
+    const tab = state.tabs.tabs.find((t) => t.id === 'tab-2')
+    expect(tab?.title).toBe('Renamed beside name')
+    // Pane title should also be updated (stale title replaced)
+    const paneTitle = state.panes.paneTitles?.['tab-2']?.['pane-2']
+    expect(paneTitle).toBe('Renamed beside name')
+  })
+
+  it('does not sync title when clicking a session without a custom title (hasTitle=false)', async () => {
+    const targetId = sessionId('untitled-session')
+
+    const projects: ProjectGroup[] = [
+      {
+        projectPath: '/home/user/project',
+        sessions: [
+          {
+            sessionId: targetId,
+            projectPath: '/home/user/project',
+            lastActivityAt: Date.now(),
+            // No title → hasTitle will be false, title will be sessionId.slice(0, 8)
+            cwd: '/home/user/project',
+          },
+        ],
+      },
+    ]
+
+    const store = createStore({
+      projects,
+      tabs: [
+        { id: 'tab-1', mode: 'claude', title: 'Claude' },
+      ],
+      activeTabId: 'tab-1',
+      panes: {
+        layouts: {
+          'tab-1': {
+            type: 'leaf',
+            id: 'pane-1',
+            content: {
+              kind: 'terminal', mode: 'claude', createRequestId: 'req-1', status: 'running',
+              resumeSessionId: targetId,
+            },
+          },
+        },
+        activePane: { 'tab-1': 'pane-1' },
+        paneTitles: {},
+      },
+    })
+
+    renderSidebar(store)
+
+    await act(async () => {
+      vi.advanceTimersByTime(100)
+    })
+
+    const sessionTitle = screen.getByText(targetId.slice(0, 8), { exact: false })
+    const sessionButton = sessionTitle.closest('button')
+    fireEvent.click(sessionButton!)
+
+    const state = store.getState()
+    const tab = state.tabs.tabs.find((t) => t.id === 'tab-1')
+    // Original title should be preserved (not overwritten by sessionId fallback)
+    expect(tab?.title).toBe('Claude')
+  })
+
   it('clicking a session already open in an agent-chat pane focuses it', async () => {
     const targetId = sessionId('freshclaude-open')