fix(desktop): mirror strip order into native tabs and drag live tab titles

Reordering a browser tab in the resource strip now reorders the desktop's
native tab list too, so restore and the agent's tab list keep the strip's
order (`reorderTab` returns as an optional bridge method). Dragging a tab
into the chat carries the strip's live title rather than the title captured
when the tab was added. The fork route test follows the new policy that
stored browser rows are dropped.

Author: waleedlatif1

apps/desktop/src/main/browser-agent/session.test.ts

@@ -2403,6 +2403,19 @@ describe('browser-agent session', () => {
     ])
   })
 
+  it('reorders tabs to the order the resource strip asks for', () => {
+    const first = session.ensureTab()
+    const second = session.addTab()
+    const third = session.addTab()
+
+    session.reorderTab(third.id, 0)
+    expect(session.listTabs().map((tab) => tab.tabId)).toEqual([third.id, first.id, second.id])
+
+    session.reorderTab(third.id, 99)
+    expect(session.listTabs().map((tab) => tab.tabId)).toEqual([first.id, second.id, third.id])
+    expect(() => session.reorderTab('999', 0)).toThrow(/No tab with id 999/)
+  })
+
   it('allows creation and reopening beyond eight browser tabs', () => {
     session.ensureTab()
     for (let index = 1; index < 12; index++) {

apps/desktop/src/main/browser-agent/session.ts

@@ -3197,6 +3197,28 @@ export function switchAutomationTab(tabId: string): AgentTab {
   return tab
 }
 
+/**
+ * Moves a tab to a final list index. The renderer's resource strip owns tab
+ * order; this keeps the native list — what restore and `browser_list_tabs`
+ * report — in the same order.
+ */
+export function reorderTab(tabId: string, targetIndex: number): AgentTab {
+  restoreBrowserSession()
+  const currentIndex = tabs.findIndex((entry) => entry.id === tabId)
+  if (currentIndex < 0) {
+    throw new SessionError(`No tab with id ${tabId} — call browser_list_tabs.`)
+  }
+  const tab = tabs[currentIndex]
+  const nextIndex = Math.max(0, Math.min(tabs.length - 1, Math.trunc(targetIndex)))
+  if (nextIndex === currentIndex) return tab
+
+  tabs.splice(currentIndex, 1)
+  tabs.splice(nextIndex, 0, tab)
+  persistBrowserSession()
+  events?.onTabsChanged()
+  return tab
+}
+
 /**
  * Closes a tab. When the agent closes its own working tab it moves on to the
  * neighbour so its next page tool has a target; a close the user made leaves

apps/desktop/src/main/ipc.test.ts

@@ -1146,6 +1146,17 @@ describe('registerIpcHandlers', () => {
     expect(() => handler?.(appEvent, { action: 'reload' })).not.toThrow()
   })
 
+  it('restricts browser-tab reordering to typed app-origin messages', () => {
+    const { on } = collectHandlers()
+    const handler = on.get('browser-agent:reorder-tab')
+
+    expect(() => handler?.(evilEvent, '1', 0)).not.toThrow()
+    expect(() => handler?.(appEvent, 1, 0)).not.toThrow()
+    expect(() => handler?.(appEvent, '1', '0')).not.toThrow()
+    expect(() => handler?.(appEvent, '1', Number.NaN)).not.toThrow()
+    expect(() => handler?.(appEvent, '1', 0)).not.toThrow()
+  })
+
   it('restricts browser-panel focus updates to boolean app-origin messages', () => {
     const { on } = collectHandlers()
     const handler = on.get('browser-agent:set-panel-focused')

apps/desktop/src/main/ipc.ts

@@ -54,6 +54,7 @@ import {
   getBrowserDownloadsState,
   grantSiteOriginForUserNavigation,
   peekTabsState,
+  reorderTab,
   setBrowserAppTheme,
   showBrowserDownloadInFolder,
   showBrowserDownloadsMenu,
@@ -1171,6 +1172,26 @@ export function registerIpcHandlers(deps: IpcDeps): void {
         void handlePanelAction(scope, panelAction).catch(() => {})
       },
     },
+    'browser-agent:reorder-tab': {
+      kind: 'send',
+      gate: 'app-origin',
+      requires: 'browser',
+      passSender: true,
+      handler: (sender, tabId, targetIndex, rawScope) => {
+        const scope = activeRendererScope(browserScopeBySender, sender as WebContents, rawScope)
+        if (
+          !scope ||
+          typeof tabId !== 'string' ||
+          typeof targetIndex !== 'number' ||
+          !Number.isFinite(targetIndex)
+        ) {
+          return
+        }
+        try {
+          withBrowserScope(scope, () => reorderTab(tabId, targetIndex))
+        } catch {}
+      },
+    },
     'browser-agent:set-panel-bounds': {
       kind: 'send',
       gate: 'app-origin',

apps/desktop/src/preload/index.ts

@@ -228,6 +228,9 @@ const api: SimDesktopApi = {
       ipcRenderer.invoke('browser-agent:dispose-scope', scopeId),
     suspendScope: (scopeId: string): Promise<boolean> =>
       ipcRenderer.invoke('browser-agent:suspend-scope', scopeId),
+    reorderTab: (tabId: string, targetIndex: number, scopeId: string): void => {
+      ipcRenderer.send('browser-agent:reorder-tab', tabId, targetIndex, scopeId)
+    },
     setPanelBounds: (
       bounds: BrowserPanelBounds | null,
       anchor: BrowserPanelAnchor | null,

apps/sim/app/api/mothership/chats/[chatId]/fork/route.test.ts

@@ -307,7 +307,7 @@ describe('POST /api/mothership/chats/[chatId]/fork', () => {
     expect(dbChainMockFns.values.mock.calls[0][0].title).toBe('Fork | Generate Logs')
   })
 
-  it('repairs legacy page-level browser resources while forking', async () => {
+  it('drops legacy browser rows while forking, since the desktop app owns those pages', async () => {
     dbChainMockFns.limit.mockResolvedValue([
       {
         ...parentRow,
@@ -318,6 +318,7 @@ describe('POST /api/mothership/chats/[chatId]/fork', () => {
             title: 'mship-todo (Channel) - sim - Slack',
           },
           { type: 'browser', id: 'browser-session', title: 'Browser' },
+          { type: 'file', id: 'file-1', title: 'report.csv' },
         ],
       },
     ])
@@ -326,7 +327,7 @@ describe('POST /api/mothership/chats/[chatId]/fork', () => {
 
     expect(res.status).toBe(200)
     expect(dbChainMockFns.values.mock.calls[0][0].resources).toEqual([
-      { type: 'browser', id: 'browser-session', title: 'Browser' },
+      { type: 'file', id: 'file-1', title: 'report.csv' },
     ])
   })
 

apps/sim/app/workspace/[workspaceId]/home/components/mothership-view/components/resource-tabs/resource-tabs.tsx

@@ -22,7 +22,11 @@ import {
 } from '@sim/emcn'
 import { Columns3, Eye, Pencil } from '@sim/emcn/icons'
 import { browserTabTitle } from '@/lib/browser-agent/tab-label'
-import { openBrowserTab, sendBrowserPanelAction } from '@/lib/browser-agent/transport'
+import {
+  openBrowserTab,
+  reorderBrowserTab,
+  sendBrowserPanelAction,
+} from '@/lib/browser-agent/transport'
 import { SIM_RESOURCE_DRAG_TYPE, SIM_RESOURCES_DRAG_TYPE } from '@/lib/copilot/resource-types'
 import { isEphemeralResource } from '@/lib/copilot/resources/types'
 import { openTerminal } from '@/lib/terminal/transport'
@@ -396,11 +400,20 @@ export function ResourceTabs({
     [chatId, desktopScopeId, onRemoveResource, resources, selectedIds]
   )
 
+  /** The strip's own title for a resource — a browser tab's is its live page title. */
+  const withStripTitle = useCallback(
+    (resource: MothershipResource): MothershipResource => {
+      const title = tabs.find((tab) => tab.id === resource.id)?.title
+      return title && title !== resource.title ? { ...resource, title } : resource
+    },
+    [tabs]
+  )
+
   const handleTabDragStart = useCallback(
     (e: ReactDragEvent<HTMLDivElement>, id: string, drag: TabStripDragContext) => {
       const resource = resources.find((r) => r.id === id)
       if (!resource) return
-      const selected = resources.filter((r) => selectedIds.has(r.id))
+      const selected = resources.filter((r) => selectedIds.has(r.id)).map(withStripTitle)
       const isMultiDrag = selected.length > 1 && selectedIds.has(resource.id)
       if (isMultiDrag) {
         e.dataTransfer.effectAllowed = 'copy'
@@ -424,12 +437,13 @@ export function ResourceTabs({
       // and a drop target asking for `copy` is refused outright unless copying
       // is allowed too.
       e.dataTransfer.effectAllowed = 'copyMove'
+      const { type, id: resourceId, title } = withStripTitle(resource)
       e.dataTransfer.setData(
         SIM_RESOURCE_DRAG_TYPE,
-        JSON.stringify({ type: resource.type, id: resource.id, title: resource.title })
+        JSON.stringify({ type, id: resourceId, title })
       )
     },
-    [resources, selectedIds]
+    [resources, selectedIds, withStripTitle]
   )
 
   const handleReorder = useCallback(
@@ -440,6 +454,12 @@ export function ResourceTabs({
       const [moved] = reordered.splice(fromIndex, 1)
       reordered.splice(targetIndex, 0, moved)
       onReorderResources(reordered)
+      // Browser tabs are not stored with the chat; their order lives in the
+      // desktop's native list, which restore and the agent read back.
+      if (moved.type === 'browser') {
+        const browserIndex = reordered.filter((r) => r.type === 'browser').indexOf(moved)
+        reorderBrowserTab(moved.id, browserIndex, desktopScopeId)
+      }
       if (chatId) {
         const persistable = reordered.filter((r) => !isEphemeralResource(r))
         if (persistable.length > 0) {
@@ -448,7 +468,7 @@ export function ResourceTabs({
       }
     },
     // eslint-disable-next-line react-hooks/exhaustive-deps
-    [chatId, resources, onReorderResources]
+    [chatId, desktopScopeId, resources, onReorderResources]
   )
 
   const previewToggle =

apps/sim/lib/browser-agent/transport.test.ts

@@ -29,6 +29,7 @@ const {
   openUrlAvailable,
   panelAction,
   registerSitePermissionPromptSupport,
+  reorderTab,
   restoreScope,
   nativeSuspendScope,
   setPageState,
@@ -69,6 +70,7 @@ const {
   openUrlAvailable: { current: true },
   panelAction: vi.fn(),
   registerSitePermissionPromptSupport: vi.fn(),
+  reorderTab: vi.fn(),
   restoreScope: vi.fn(async (scopeId: string) => ({ scopeId, tabs: [], activeTabId: null })),
   nativeSuspendScope: vi.fn(async () => true),
   setPageState: vi.fn(),
@@ -108,6 +110,7 @@ vi.mock('@/lib/desktop', () => ({
       openUrl: openUrlAvailable.current ? openUrl : undefined,
       panelAction,
       registerSitePermissionPromptSupport,
+      reorderTab,
       restoreScope,
       suspendScope: nativeSuspendScope,
       setPanelBounds,
@@ -160,6 +163,7 @@ import {
   onBrowserToolbarCommand,
   openBrowserTab,
   openUrlInNewBrowserTab,
+  reorderBrowserTab,
   reportBrowserPanelBounds,
   reportBrowserPanelFocused,
   reportBrowserTheme,
@@ -337,6 +341,12 @@ describe('browser panel transport', () => {
     expect(supportsAtomicBrowserPanelOcclusion()).toBe(true)
   })
 
+  it('mirrors a strip reorder into the native tab list', () => {
+    reorderBrowserTab('tab-3', 1)
+
+    expect(reorderTab).toHaveBeenCalledWith('tab-3', 1, 'chat-test')
+  })
+
   it('opens and scopes the native browser toolbar menu', () => {
     showBrowserToolbarMenu({ x: 10, y: 20 }, 'chat-a')
     expect(showToolbarMenu).toHaveBeenCalledWith({ x: 10, y: 20 }, 'chat-a')

apps/sim/lib/browser-agent/transport.ts

@@ -383,6 +383,18 @@ export async function openUrlInNewBrowserTab(
   return state?.activeTabId ?? null
 }
 
+/**
+ * Mirrors a resource-strip reorder into the native tab list, so restore and
+ * the agent's tab list keep the strip's order. Older shells keep native order.
+ */
+export function reorderBrowserTab(
+  tabId: string,
+  targetIndex: number,
+  scopeId = currentBrowserScopeId()
+): void {
+  bridge()?.reorderTab?.(tabId, targetIndex, scopeId)
+}
+
 /** Mirrors Sim's raw light/dark/system preference into embedded pages. */
 export function reportBrowserTheme(theme: BrowserTheme): void {
   bridge()?.setTheme(theme)

packages/desktop-bridge/contract-snapshot.ts

@@ -1085,6 +1085,11 @@ export interface SimDesktopBrowserAgentApi {
   disposeScope(scopeId: string): Promise<boolean>
   /** Closes a soft-deleted chat's live pages while retaining its restart descriptor. */
   suspendScope(scopeId: string): Promise<boolean>
+  /**
+   * Move a live tab to a final list index, mirroring the resource strip.
+   * Optional for compatibility with installed shells that predate strip-owned order.
+   */
+  reorderTab?(tabId: string, targetIndex: number, scopeId: string): void
   /**
    * Report where the browser panel sits in the window (CSS pixels relative
    * to the viewport), or null when the panel is hidden/unmounted. The main