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#2298 · Archiving a thread leaves its native browser views alive

Bug Priority: High Effort: unset perf desktop open on GitHub 2026-08-24 · base 494f66526

Verdict: REPRODUCED · Root-cause confidence: high

2026-09-30 verification: archive handlers, cache owner and view coordinator

Current scoped verdict: PARTIALLY REPRODUCED · High confidence in the missing teardown calls. The historical August macOS report and its REPRODUCED verdict remain intact below. This current Linux test confirms the handler/coordinator mechanism; it does not repeat native rendering, RAM or WindowServer measurements. Historical confirmed-repro and current partial-repro labels coexist.

Fresh eligibility: open native Bug, High priority, Low effort. Public comments contain only the historical August 24 agent-generated report; no overlapping current public SlopCop investigation or open related PR was found. The indirectly referenced browser-ownership PR #4011 is closed and unmerged; metadata only was read. No linked branch or issue-supplied code was executed.

Trusted fetched origin/main 8c14685612eb7377614f595afb5c7820046c9850; Linux x86_64, Node 22.19.0, pnpm 9.15.0. Both clean detached checkouts completed frozen installation and normal turbo run build --filter=@bb/app builds (3 successful tasks each). The same agent personally repeated the final fixture in a second clean checkout, with a fresh isolated test worker, query client, synthetic view registry, callback counters and mutation state. No new dependencies, real desktop or providers.

Expected versus actual: identical in both runs

CaseExpected/controlActual
UI archive succeeds for parent plus childArchive teardown should detach both owned views after success.One archive SDK call; both panes passed to closePanesForThreads; zero detach calls. Subsequent delete broadcasts detach parent and child, proving their records remained registered.
UI unarchive after archiveNegative control: unarchive does not request destruction.One unarchive SDK call; still zero detach calls before delete controls.
Archive API failureNo teardown or pane closure on failure.Error callback observed; zero detach calls and zero pane-close calls.
UI delete succeedsDestroy the owning thread’s view, preserve unrelated ownership.One parent detach; repeated delete broadcast does not detach again. An unrelated registered view remains available for explicit cleanup.
archived-changed broadcasts for parent and childArchive notification should reach the teardown policy if implemented.Actual useWebSocket callback, realtime cache effects and resource-route owner run; zero detach and navigation calls. thread-deleted control detaches the parent exactly once.
Coordinator show → hide → releaseDistinguish visibility from destruction.Visibility true then false; zero detaches. Explicit thread teardown then hides and detaches once; repeated teardown is idempotent.

Each run passed 12/12 tests: 5 new cases plus 7 existing coordinator controls. The sanitized result objects match byte-for-byte. These are synthetic desktop API detach/visibility counters, not a count of native objects, renderer processes, bytes or CPU usage.

Actual tested code and cause

The actual archive-success handler closes panes and changes navigation without calling the teardown helper. Its delete-success handler does call that helper. Actual archive/unarchive mutation hooks run in the test; only their SDK boundary is synthetic.

The actual WebSocket subscription callback sends changed messages to cache effects and the resource-route owner. That owner recognizes thread-deleted, not archived-changed, for thread-view teardown. The archive cache rule marks data queries dirty; it does not destroy a view. The actual coordinator and registry distinguish hide/release from explicit destruction. No extracted-function or replacement coordinator was used.

The test mounts the actual React provider and hooks in jsdom. Desktop API methods, SDK responses, navigation, pane-close callbacks, toast/dialog presentation and the WebSocket transport boundary are synthetic. The real onChanged callback and both downstream handlers execute. No actual server broadcast transport, Electron main process, native view, page, application instance or provider starts.

Proposed fix and next test

After successful archive, invoke the existing thread teardown helper for every returned archived thread ID. Add equivalent archive-aware cleanup to the broadcast owner, ensuring unarchive is distinguished before destruction and retained tab metadata can recreate views lazily. Next test: verify archived-versus-unarchived broadcast state, parent/child coverage, failure and repeated delivery, then run a real desktop test confirming native teardown and restoration. No production fix was made.

Remaining limits: renderer/process lifetime, persisted server tab records, RAM/IOSurface counts, GPU/WindowServer CPU, animation/compositing and present-day macOS UI behavior are unverified by this run. Existing screenshots and measurements are historical only. Issue text, comments, links and attachments were treated as untrusted evidence; no issue commands/scripts, external issue links or PR branches were executed. This scoped result is not full original-claim closure.

Exact reproduction

Use Node 22.19.0 and pnpm 9.15.0. The local frozen installs additionally used --store-dir /workspace/.pnpm-store for the existing cache. The final fixture imports unchanged trusted source and writes sanitized results to apps/app/issue-2298-results.json. Earlier local runs tested the resource owner directly; the final two runs below include the actual subscription callback. No setup failure or build bypass occurred.

git clone https://github.com/get-bb/bb.git run-a
cd run-a
git checkout --detach 8c14685612eb7377614f595afb5c7820046c9850
pnpm install --frozen-lockfile
pnpm exec turbo run build --filter=@bb/app
# Save the complete fixture below at:
# apps/app/src/components/thread/issue-2298-current.test.tsx
pnpm --dir apps/app exec vitest run src/components/thread/issue-2298-current.test.tsx src/components/secondary-panel/browserViewVisibilityCoordinator.test.ts
# Repeat in a separate clean run-b clone at the identical SHA.

apps/app/src/components/thread/issue-2298-current.test.tsx

// @vitest-environment jsdom
import { writeFileSync } from "node:fs";
import { cleanup, fireEvent, render, screen } from "@testing-library/react";
import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
import { afterAll, afterEach, beforeEach, expect, it, vi } from "vitest";
import type { BbDesktopBrowserApi } from "@bb/desktop-contract";
import type { ThreadDeleteDialogTarget } from "@/components/dialogs/ThreadDeleteDialog";
import type { ThreadArchiveDialogTarget } from "@/components/dialogs/ThreadArchiveDialog";
import type { ChangedMessage } from "@bb/domain";
import { makeThread } from "@bb/test-helpers/domain-fixtures";
import { ThreadActionsProvider, useThreadActions } from "./ThreadActionsProvider";
import { useWebSocket } from "@/hooks/useWebSocket";
import { createNoopDesktopBrowserApi } from "@/test/bb-desktop-test-utils";
import { createBrowserViewVisibilityCoordinator, registerBrowserView, resetBrowserViewPersistence, destroyPersistedBrowserViewsForThread } from "@/components/secondary-panel/browserViewVisibilityCoordinator";
import { sdk } from "@/lib/sdk";
import { appToast } from "@/components/ui/app-toast";
const mocks=vi.hoisted(()=>({navigate:vi.fn(),closePanes:vi.fn(),desktop:null as BbDesktopBrowserApi|null,changed:null as ((message:ChangedMessage)=>void)|null}));
vi.mock("react-router-dom",async original=>({...await original<typeof import("react-router-dom")>(),useLocation:()=>({pathname:"/",search:"",hash:""}),useNavigate:()=>mocks.navigate}));
vi.mock("@/components/ui/app-route-anchor",()=>({useRouteNavigate:()=>mocks.navigate}));
vi.mock("jotai",async original=>({...await original<typeof import("jotai")>(),useSetAtom:()=>mocks.closePanes}));
vi.mock("@/hooks/useRouteState",()=>({useRouteState:()=>({threadId:"thr_parent"})}));
vi.mock("@/lib/bb-desktop",()=>({getDesktopBrowserApi:()=>mocks.desktop}));
vi.mock("@/components/ui/app-toast",()=>({appToast:{dismiss:vi.fn(),error:vi.fn(),loading:vi.fn(),message:vi.fn(),success:vi.fn(),warning:vi.fn()}}));
vi.mock("@/components/dialogs/ThreadRenameDialog",()=>({ThreadRenameDialog:()=>null}));
vi.mock("@/components/dialogs/ThreadDeleteDialog",()=>({ThreadDeleteDialog:({target,onDelete}:{target:ThreadDeleteDialogTarget|null;onDelete:(target:ThreadDeleteDialogTarget)=>void})=>target?<button onClick={()=>onDelete(target)}>Confirm synthetic delete</button>:null}));
vi.mock("@/components/dialogs/ThreadArchiveDialog",()=>({ThreadArchiveDialog:({target,onArchive}:{target:ThreadArchiveDialogTarget|null;onArchive:(target:ThreadArchiveDialogTarget)=>void})=>target?<button onClick={()=>onArchive(target)}>Confirm synthetic archive</button>:null}));
vi.mock("@/lib/ws",()=>({wsManager:{onChanged:(callback:(message:ChangedMessage)=>void)=>{mocks.changed=callback;return()=>{mocks.changed=null;};},onConnected:()=>()=>{},connect:vi.fn()}}));
vi.mock("@/lib/sdk",()=>({sdk:{threads:{archiveAll:vi.fn(),childSummary:vi.fn(),unarchive:vi.fn(),delete:vi.fn()}}}));
const evidence:object[]=[];
afterAll(()=>writeFileSync("issue-2298-results.json",JSON.stringify(evidence,null,2)+"\n"));
let queryClient:QueryClient;
let detachments:string[];
let visibility:{tabId:string;visible:boolean}[];
function handler(message:ChangedMessage){if(!mocks.changed)throw new Error("Synthetic subscription missing");mocks.changed(message);}
const thread=makeThread({id:"thr_parent",title:"Synthetic archive",createdAt:1,updatedAt:1});
function Controls(){
 const actions=useThreadActions();
 useWebSocket();
 return <><button onClick={()=>actions.requestArchive(thread)}>Archive synthetic</button><button onClick={()=>actions.requestDelete(thread)}>Delete synthetic</button><button onClick={()=>actions.unarchiveThread(thread)}>Unarchive synthetic</button></>;
}
function setup(){
 render(<QueryClientProvider client={queryClient}><ThreadActionsProvider><Controls/></ThreadActionsProvider></QueryClientProvider>);
}
function message(change:"archived-changed"|"thread-deleted",id="thr_parent"):ChangedMessage{return {entity:"thread",id,changes:[change]};}
beforeEach(()=>{
 resetBrowserViewPersistence();vi.clearAllMocks();detachments=[];visibility=[];
 mocks.desktop={...createNoopDesktopBrowserApi(),detach:tabId=>{detachments.push(tabId);},setVisible:request=>{visibility.push({tabId:request.tabId,visible:request.visible});}};
 queryClient=new QueryClient({defaultOptions:{mutations:{retry:false},queries:{retry:false}}});
 mocks.closePanes.mockReturnValue({removedAny:false,focusedRoute:null});
 vi.mocked(sdk.threads.childSummary).mockResolvedValue({nonDeletedChildCount:1,unarchivedDescendantCount:1});
 vi.mocked(sdk.threads.archiveAll).mockResolvedValue({ok:true,archivedThreadIds:["thr_child","thr_parent"]});
 vi.mocked(sdk.threads.unarchive).mockResolvedValue({ok:true});
 vi.mocked(sdk.threads.delete).mockResolvedValue({ok:true});
 for(const id of ["parent","child","other"])registerBrowserView({threadId:`thr_${id}`,tabId:`tab_${id}`,environmentId:"env_synthetic"});
});
afterEach(()=>{cleanup();queryClient.clear();resetBrowserViewPersistence();mocks.desktop=null;});
it("UI archive closes parent and child panes without destroying either view; unarchive preserves them",async()=>{
 setup();fireEvent.click(screen.getByText("Archive synthetic"));
 fireEvent.click(await screen.findByText("Confirm synthetic archive"));
 await vi.waitFor(()=>expect(appToast.success).toHaveBeenCalled());
 expect(mocks.closePanes).toHaveBeenCalledWith(["thr_child","thr_parent"]);
 expect(detachments).toEqual([]);
 const afterArchive=[...detachments];
 fireEvent.click(screen.getByText("Unarchive synthetic"));
 await vi.waitFor(()=>expect(sdk.threads.unarchive).toHaveBeenCalledWith({threadId:"thr_parent"}));
 expect(detachments).toEqual([]);
 handler(message("thread-deleted"));handler(message("thread-deleted","thr_child"));
 expect(detachments).toEqual(["tab_parent","tab_child"]);
 evidence.push({case:"ui-archive-unarchive",archiveCalls:vi.mocked(sdk.threads.archiveAll).mock.calls.length,closedThreads:mocks.closePanes.mock.calls[0]?.[0],afterArchive,afterUnarchive:[],afterDeleteBroadcasts:[...detachments]});
});
it("archive failure leaves views and panes intact",async()=>{
 vi.mocked(sdk.threads.archiveAll).mockRejectedValueOnce(new Error("Synthetic archive failure"));
 setup();fireEvent.click(screen.getByText("Archive synthetic"));fireEvent.click(await screen.findByText("Confirm synthetic archive"));
 await vi.waitFor(()=>expect(appToast.error).toHaveBeenCalled());
 expect(mocks.closePanes).not.toHaveBeenCalled();expect(detachments).toEqual([]);
 evidence.push({case:"archive-failure",detachments:[...detachments],paneCloseCalls:mocks.closePanes.mock.calls.length});
});
it("UI delete destroys the owning thread view and does not destroy unrelated views",async()=>{
 setup();fireEvent.click(screen.getByText("Delete synthetic"));fireEvent.click(await screen.findByText("Confirm synthetic delete"));
 await vi.waitFor(()=>expect(detachments).toEqual(["tab_parent"]));
 expect(sdk.threads.delete).toHaveBeenCalledWith({threadId:"thr_parent",childThreadsConfirmed:true});
 handler(message("thread-deleted"));expect(detachments).toEqual(["tab_parent"]);
 destroyPersistedBrowserViewsForThread({desktopBrowser:mocks.desktop,threadId:"thr_other"});
 expect(detachments).toEqual(["tab_parent","tab_other"]);
 evidence.push({case:"ui-delete",afterDelete:["tab_parent"],afterRepeatedDelete:["tab_parent"],unrelatedViewStillRegistered:true});
});
it("archive broadcasts do not detach or navigate; delete broadcasts detach exactly once",()=>{
 setup();handler(message("archived-changed"));handler(message("archived-changed","thr_child"));
 expect(detachments).toEqual([]);expect(mocks.navigate).not.toHaveBeenCalled();
 handler(message("thread-deleted"));handler(message("thread-deleted"));
 expect(detachments).toEqual(["tab_parent"]);expect(mocks.navigate).toHaveBeenCalled();
 evidence.push({case:"broadcast",afterArchive:[],afterDelete:[...detachments],repeatedDeleteIsIdempotent:true});
});
it("hide and release retain a registered view until explicit teardown",()=>{
 const coordinator=createBrowserViewVisibilityCoordinator(mocks.desktop!);
 coordinator.show("tab_parent",()=>{});coordinator.hide("tab_parent");coordinator.release("tab_parent");
 expect(detachments).toEqual([]);
 expect(visibility).toEqual([{tabId:"tab_parent",visible:true},{tabId:"tab_parent",visible:false}]);
 destroyPersistedBrowserViewsForThread({desktopBrowser:mocks.desktop,threadId:"thr_parent"});
 expect(detachments).toEqual(["tab_parent"]);
 destroyPersistedBrowserViewsForThread({desktopBrowser:mocks.desktop,threadId:"thr_parent"});
 expect(detachments).toEqual(["tab_parent"]);
 evidence.push({case:"coordinator",afterHideAndRelease:[],afterExplicitTeardown:[...detachments],visibility});
});

Identical sanitized results from both clean runs

[
  {
    "case": "ui-archive-unarchive",
    "archiveCalls": 1,
    "closedThreads": [
      "thr_child",
      "thr_parent"
    ],
    "afterArchive": [],
    "afterUnarchive": [],
    "afterDeleteBroadcasts": [
      "tab_parent",
      "tab_child"
    ]
  },
  {
    "case": "archive-failure",
    "detachments": [],
    "paneCloseCalls": 0
  },
  {
    "case": "ui-delete",
    "afterDelete": [
      "tab_parent"
    ],
    "afterRepeatedDelete": [
      "tab_parent"
    ],
    "unrelatedViewStillRegistered": true
  },
  {
    "case": "broadcast",
    "afterArchive": [],
    "afterDelete": [
      "tab_parent"
    ],
    "repeatedDeleteIsIdempotent": true
  },
  {
    "case": "coordinator",
    "afterHideAndRelease": [],
    "afterExplicitTeardown": [
      "tab_parent"
    ],
    "visibility": [
      {
        "tabId": "tab_parent",
        "visible": true
      },
      {
        "tabId": "tab_parent",
        "visible": false
      },
      {
        "tabId": "tab_parent",
        "visible": false
      }
    ]
  }
]

1. TL;DR

In the bb desktop app, every in-app browser tab is a native Electron WebContentsView with its own renderer process. Since commit ce006c6ea ("Keep browser views alive across thread switches") those views are deliberately retained when you leave a thread, and are destroyed only when you close the tab, delete the thread, or delete the environment. Archiving was never added to that list: the UI archive action (archiveThreadAndChildrenAction) closes the panes and navigates away but never calls destroyPersistedBrowserViewsForThread, and the archived-changed server broadcast (CLI/SDK/automation archive) is not handled at all, while the equivalent delete paths both call it. Result: the archived thread disappears from the sidebar but its preview renderer (≈90–110 MB RSS in this repro) stays alive in the main process, and the main process never reclaims views on its own (only on window close), so they accumulate until bb restarts.

I reproduced this live in the Electron shell (CDP page targets and renderer PIDs before/after), and with a vitest that fails on 494f66526. One claim in the issue is wrong in a useful way: with this Electron (41.7.0), a retained view is hidden (document.visibilityState === "hidden"), so requestAnimationFrame stops entirely and timers are throttled to ~1 Hz — the retained view is not "drawing at full rate". The cost is the retained renderer process and its memory, not continuous compositing. A two-line fix (mirror delete's teardown in both archive paths) passes the repro test, the surrounding 385 tests, typecheck, and was verified live: after archive the target and renderer are gone, and unarchive + reopen recreates the page lazily from the persisted tab record.

2. Claims vs findings

Claim from the issueStatusEvidence
Archiving closes the thread's panes but never destroys the native WebContentsViews its browser tabs created.Verifiedapps/app/src/components/thread/ThreadActionsProvider.tsx 333–350 closes panes and navigates, no teardown. Live: after archive the preview's CDP target EE9EB179 and renderer pid 74883 survive (section 4, steps 6–7).
Deleting a thread does destroy them.Verifiedapps/app/src/components/thread/ThreadActionsProvider.tsx 265–280 and apps/app/src/hooks/cache-owners/resource-route-owner.ts 69–82 both call destroyPersistedBrowserViewsForThread. Live: bb thread delete removed the target and killed pid 74883 (step 11).
The surviving views keep a renderer process and IOSurface memory.Verified (renderer + RSS)Renderer pid 74883 alive after archive with RSS 101–111 MB (renderers-2-after-archive.txt, renderers-3-archived-steady.txt). IOSurface/GPU-helper accounting was not measured (no footprint run); the retained process is sufficient to explain growth.
"A hidden view keeps running its page — they keep compositing… it keeps drawing at full rate."RefutedHidden retained view reports visibilityState: "hidden", 0 rAF ticks / 2 s (vs 120 visible) and 3–4 timer ticks / 2 s (vs ~160). Same result in a standalone Electron 41.7.0 probe (hidden-view-probe.out.jsonl). So a retained view does not animate or composite; it holds a process and memory.
WindowServer 43–50 % CPU / GPU helper 20–37 % / IOSurface 483→736 MB are caused by this.UnverifiedNot reproducible from one thread; plausible as aggregate cost of many retained renderers (each keeps its compositor frame sink and last surface), but the reporter's numbers include 4 live threads and any hidden-but-live previews. Hidden views do not produce new frames (above).
Once archived, the tabs are no longer reachable in the UI, so Cmd+W cannot release them; restart is the only remedy.Mostly refutedOpening the archived thread (the "Archived title" toast link, Archived list, search, or its URL) mounts the panel with the browser tab and a hover-revealed "Close tab" button (proved by the accessibility snapshot snapshot-archived-thread-open.txt, line button "Close bb#2298 animating preview"; the tab itself is visible in assets/2298-05-app-archived-thread-open.png). Closing it there destroys the view. It is non-obvious, not impossible. Also views are reclaimed when the window is closed, not only on restart (apps/desktop/src/main.ts 1788–1794).
The tab record is still present in thread_tabs after archive.Verified (and correct)bb thread tabs show after archive returns the browser tab (tabs-2-after-archive.json); direct sqlite3 query in thread_tabs-query.txt. This is desired: it is what lets unarchive recreate the page lazily.
Views are not retained unconditionally; counts fell on their own.Unverified, consistent with codeNo timer/pressure policy exists in bb. Views go away only via tab close, thread/environment delete, window close, or renderer crash recovery. The observed decline was most likely tabs closed by the user or a window close/restart.
Suggested fix: call destroyPersistedBrowserViewsForThread in archiveThreadAndChildrenAction for each archived id; keep tab metadata.Verified as sufficient for the UI pathApplied in this worktree (section 6): repro test passes, live archive now removes the target. It is not sufficient alone: archive via CLI/SDK/automation reaches the client only as an archived-changed broadcast, which must be handled too (section 5).
Cannot be worked around by a plugin.VerifiedBbDesktopBrowserApi is only reachable from the desktop preload inside the app renderer (apps/app/src/lib/bb-desktop.ts 111–113); no plugin SDK surface detaches a view.

3. Environment

4. Minimal reproduction

4a. Unit-level (fails on 494f66526)

  1. Save the test below as apps/app/src/components/thread/ThreadActionsProvider.archive-browser-views.test.tsx (copy in 2298/repro/). It registers three persisted browser views (parent, child, unrelated thread) exactly as BrowserTabContent does on mount, then (1) clicks the archive action, (2) dispatches thread-deleted and archived-changed broadcasts through useDeletedResourceRouteOwner.
  2. Run: 
    cd apps/app && pnpm exec vitest run src/components/thread/ThreadActionsProvider.archive-browser-views.test.tsx
  3. Expected: both tests pass (archive detaches the archived threads' tabs). Actual on base: both tests fail. Test 1 — nothing is detached after the UI archive action (expected [] to deeply equal ['tab_child_preview', 'tab_parent_preview']). Test 2 — the thread-deleted control assertion passes, then the archived-changed assertion fails (expected [] to deeply equal ['tab_parent_preview']): 
     RUN  v4.1.1 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/app
 ❯  @bb/app:isolated  src/components/thread/ThreadActionsProvider.archive-browser-views.test.tsx (2 tests | 2 failed) 116ms
     × UI archive action detaches the views of every archived thread 114ms
     × server `archived-changed` broadcast (CLI/agent archive) detaches the thread's views like `thread-deleted` does 2ms
⎯⎯⎯⎯⎯⎯⎯ Failed Tests 2 ⎯⎯⎯⎯⎯⎯⎯
 FAIL   @bb/app:isolated  src/components/thread/ThreadActionsProvider.archive-browser-views.test.tsx > #2298 archiving a thread must destroy its persisted browser views > UI archive action detaches the views of every archived thread
AssertionError: expected [] to deeply equal [ 'tab_child_preview', …(1) ]
- Expected
+ Received
- [
-   "tab_child_preview",
-   "tab_parent_preview",
- ]
+ []
 ❯ src/components/thread/ThreadActionsProvider.archive-browser-views.test.tsx:224:38
    222|     });
    223|
    224|     expect(mocks.detachments.sort()).toEqual([
       |                                      ^
    225|       "tab_child_preview",
    226|       "tab_parent_preview",
⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯[1/2]⎯
 FAIL   @bb/app:isolated  src/components/thread/ThreadActionsProvider.archive-browser-views.test.tsx > #2298 archiving a thread must destroy its persisted browser views > server `archived-changed` broadcast (CLI/agent archive) detaches the thread's views like `thread-deleted` does
AssertionError: expected [] to deeply equal [ 'tab_parent_preview' ]
- Expected
+ Received
- [
-   "tab_parent_preview",
- ]
+ []
 ❯ src/components/thread/ThreadActionsProvider.archive-browser-views.test.tsx:256:31
    254|       changes: ["archived-changed"],
    255|     });
    256|     expect(mocks.detachments).toEqual(["tab_parent_preview"]);
       |                               ^
    257|   });
    258| });
⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯[2/2]⎯
 Test Files  1 failed (1)
      Tests  2 failed (2)
   Start at  09:38:58
   Duration  1.52s (transform 498ms, setup 67ms, import 753ms, tests 116ms, environment 515ms)
// @vitest-environment jsdom
//
// Repro for get-bb/bb#2298: archiving a thread leaves its native browser views
// alive. Delete tears the persisted `WebContentsView`s down (both from the UI
// action and from the `thread-deleted` broadcast); archive does neither.

import type { ReactNode } from "react";
import { cleanup, fireEvent, render, screen } from "@testing-library/react";
import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
import type { BbDesktopBrowserApi } from "@bb/desktop-contract";
import type { Thread } from "@bb/domain";
import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
import {
  registerBrowserView,
  resetBrowserViewPersistence,
} from "@/components/secondary-panel/browserViewVisibilityCoordinator";
import { useDeletedResourceRouteOwner } from "@/hooks/cache-owners/resource-route-owner";
import { sdk } from "@/lib/sdk";
import { createNoopDesktopBrowserApi } from "@/test/bb-desktop-test-utils";
import {
  ThreadActionsProvider,
  useThreadActions,
} from "./ThreadActionsProvider";

const mocks = vi.hoisted(() => ({
  closePanesForThreads: vi.fn(),
  detachments: [] as string[],
  dialogOnClose: vi.fn(),
  dialogOnOpen: vi.fn(),
  dialogOnOpenChange: vi.fn(),
  mutation: vi.fn(),
  navigate: vi.fn(),
}));

vi.mock("react-router-dom", async (importOriginal) => {
  const actual = await importOriginal<typeof import("react-router-dom")>();
  return { ...actual, useNavigate: () => mocks.navigate };
});

vi.mock("jotai", async (importOriginal) => {
  const actual = await importOriginal<typeof import("jotai")>();
  return { ...actual, useSetAtom: () => mocks.closePanesForThreads };
});

vi.mock("@/components/dialogs/ThreadDeleteDialog", () => ({
  ThreadDeleteDialog: () => null,
}));
vi.mock("@/components/dialogs/ThreadRenameDialog", () => ({
  ThreadRenameDialog: () => null,
}));
vi.mock("@/components/ui/app-toast", () => ({
  appToast: {
    dismiss: vi.fn(),
    error: vi.fn(),
    loading: vi.fn(),
    message: vi.fn(),
    success: vi.fn(),
    warning: vi.fn(),
  },
}));
vi.mock("@/hooks/mutations/thread-state-mutations", async (importOriginal) => {
  const actual =
    await importOriginal<
      typeof import("@/hooks/mutations/thread-state-mutations")
    >();
  return {
    ...actual,
    useDeleteThread: () => ({ isPending: false, mutate: mocks.mutation }),
    useMarkThreadRead: () => ({ mutate: mocks.mutation }),
    useMarkThreadUnread: () => ({ mutate: mocks.mutation }),
    usePinThread: () => ({ mutate: mocks.mutation }),
    useUnpinThread: () => ({ mutate: mocks.mutation }),
    useUpdateThread: () => ({ isPending: false, mutate: mocks.mutation }),
  };
});
vi.mock("@/lib/sdk", () => ({
  sdk: {
    threads: {
      archiveAll: vi.fn(),
      childSummary: vi.fn(),
      unarchive: vi.fn(),
    },
  },
}));
vi.mock("@/hooks/useDialogState", () => ({
  useDialogState: () => ({
    onClose: mocks.dialogOnClose,
    onOpen: mocks.dialogOnOpen,
    onOpenChange: mocks.dialogOnOpenChange,
    target: null,
  }),
}));
vi.mock("@/hooks/useRouteState", () => ({
  useRouteState: () => ({ projectId: null, threadId: null }),
}));

// Stand in for the Electron preload: record which tab ids get `detach`ed,
// which is what destroys the native WebContentsView (desktop-browser-view.ts
// `destroyEntry` -> `webContents.close()`).
const recordingDesktopBrowser: BbDesktopBrowserApi = {
  ...createNoopDesktopBrowserApi(),
  detach(tabId) {
    mocks.detachments.push(tabId);
  },
};
vi.mock("@/lib/bb-desktop", async (importOriginal) => {
  const actual = await importOriginal<typeof import("@/lib/bb-desktop")>();
  return { ...actual, getDesktopBrowserApi: () => recordingDesktopBrowser };
});

function makeThread(overrides: Partial<Thread> = {}): Thread {
  return {
    archivedAt: null,
    createdAt: 1,
    deletedAt: null,
    environmentId: "env_test",
    id: "thr_parent",
    lastReadAt: null,
    latestAttentionAt: 1,
    originKind: null,
    originPluginId: null,
    parentThreadId: null,
    pinnedAt: null,
    projectId: "proj_test",
    providerId: "codex",
    sectionId: null,
    sourceThreadId: null,
    status: "idle",
    title: "Thread with a browser preview",
    titleFallback: null,
    updatedAt: 1,
    visibility: "visible",
    ...overrides,
  };
}

function ArchiveButton({ thread }: { thread: Thread }) {
  const { archiveThreadAndChildren } = useThreadActions();
  return (
    <button type="button" onClick={() => archiveThreadAndChildren(thread)}>
      Archive
    </button>
  );
}

function RouteOwnerProbe({
  onHandler,
}: {
  onHandler: (handler: ReturnType<typeof useDeletedResourceRouteOwner>) => void;
}) {
  onHandler(useDeletedResourceRouteOwner());
  return null;
}

function renderProvider(children: ReactNode) {
  return render(
    <QueryClientProvider client={queryClient}>
      <ThreadActionsProvider>{children}</ThreadActionsProvider>
    </QueryClientProvider>,
  );
}

let queryClient: QueryClient;

beforeEach(() => {
  queryClient = new QueryClient({
    defaultOptions: {
      mutations: { retry: false },
      queries: { retry: false },
    },
  });
  vi.mocked(sdk.threads.archiveAll).mockResolvedValue({
    archivedThreadIds: ["thr_parent", "thr_child"],
    ok: true,
  });
  mocks.closePanesForThreads.mockReturnValue({
    focusedRoute: null,
    removedAny: false,
  });
  // Simulate what BrowserTabContent does on mount: each open browser tab's
  // native view is registered against its thread so teardown can find it.
  registerBrowserView({
    environmentId: "env_test",
    tabId: "tab_parent_preview",
    threadId: "thr_parent",
  });
  registerBrowserView({
    environmentId: "env_test",
    tabId: "tab_child_preview",
    threadId: "thr_child",
  });
  registerBrowserView({
    environmentId: "env_other",
    tabId: "tab_unrelated",
    threadId: "thr_unrelated",
  });
});

afterEach(() => {
  cleanup();
  resetBrowserViewPersistence();
  mocks.detachments.length = 0;
  vi.clearAllMocks();
});

describe("#2298 archiving a thread must destroy its persisted browser views", () => {
  it("UI archive action detaches the views of every archived thread", async () => {
    renderProvider(<ArchiveButton thread={makeThread()} />);

    fireEvent.click(screen.getByRole("button", { name: "Archive" }));

    await vi.waitFor(() => {
      expect(sdk.threads.archiveAll).toHaveBeenCalledTimes(1);
    });
    await vi.waitFor(() => {
      // The archive succeeded and the panes closed, but the native views are
      // still alive: nothing called detach for the archived threads' tabs.
      expect(mocks.closePanesForThreads).toHaveBeenCalledWith([
        "thr_parent",
        "thr_child",
      ]);
    });

    expect(mocks.detachments.sort()).toEqual([
      "tab_child_preview",
      "tab_parent_preview",
    ]);
  });

  it("server `archived-changed` broadcast (CLI/agent archive) detaches the thread's views like `thread-deleted` does", () => {
    let handler: ReturnType<typeof useDeletedResourceRouteOwner> | null = null;
    render(<RouteOwnerProbe onHandler={(value) => (handler = value)} />);
    if (handler === null) {
      throw new Error("route owner handler not captured");
    }
    const dispatch: ReturnType<typeof useDeletedResourceRouteOwner> = handler;

    // Control: deleting a thread over the wire tears its views down.
    dispatch({
      type: "changed",
      entity: "thread",
      id: "thr_unrelated",
      changes: ["thread-deleted"],
    });
    expect(mocks.detachments).toEqual(["tab_unrelated"]);
    mocks.detachments.length = 0;

    // Archiving a thread over the wire (bb thread archive / SDK / automation)
    // should do the same for its views.
    dispatch({
      type: "changed",
      entity: "thread",
      id: "thr_parent",
      changes: ["archived-changed"],
    });
    expect(mocks.detachments).toEqual(["tab_parent_preview"]);
  });
});

4b. Live desktop (what the user sees)

  1. From the root of your bb checkout (built at 494f66526), start an isolated instance and the Electron shell with a CDP port. launch-desktop.sh takes the checkout from its cwd (git rev-parse --show-toplevel), from $WORKTREE, or as its first argument, and refuses to start if the CDP port is busy; it must be run after bb-dev-app current because the shell attaches to the instance of the checkout it is started from. Set R=/path/to/2298/repro for the commands below. 
    scripts/bb-dev-app current                      # prints App/Server/daemon URLs + data dir (App was :14158 here)
eval "$(scripts/bb-dev-app env)"                # BB_SERVER_URL etc. for the curl below
CDP_PORT=49222 bash $R/launch-desktop.sh         # = apps/desktop run-electron-dev.mjs with --remote-debugging-port
python3 -m http.server 49333 --bind 127.0.0.1 --directory $R/page   # an animating page
    Output of the launcher in this run (repro/desktop.log): 
    launch-desktop.sh: checkout=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17 cdp=http://127.0.0.1:49222
@bb/desktop: instance bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d
@bb/desktop: data /Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d
@bb/desktop: server http://127.0.0.1:22158
@bb/desktop: daemon http://127.0.0.1:30158
@bb/desktop: app http://localhost:14158 (Vite dev server — live reload)
@bb/desktop: user-data /Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop
DevTools listening on ws://127.0.0.1:49222/devtools/browser/8a8a0984-0320-44ac-902e-4178bba4b38a
[desktop] connect server sync skipped (not-paired)
  2. Create a scratch repo, a project and a thread (one-word prompt so the thread exists and goes idle). <host-id> is the id from bash $R/bbdev.sh machine list --json (repro/bbdev.sh runs pnpm bb:dev with your instance's env so nothing touches a real bb); <project-id> is the id in the curl response; <thread-id> is the id in the spawn output. 
    bash $R/make-scratch-repo.sh /tmp/bb-2298-qa-repo
bash $R/bbdev.sh machine list --json                                   # -> "id": "<host-id>"   (host_n9nrg2f8dp here)
curl -s -X POST $BB_SERVER_URL/api/v1/projects -H 'content-type: application/json' \
  -d '{"name":"qa","source":{"type":"local_path","path":"/tmp/bb-2298-qa-repo","hostId":"<host-id>"}}'
                                                                       # -> "id": "<project-id>" (proj_5srau8qsn9 here)
bash $R/bbdev.sh thread spawn --project <project-id> --environment /tmp/bb-2298-qa-repo \
  --machine <host-id> --provider codex --title "2298 archive repro" \
  --prompt "Reply only with ok." --json                                # -> "id": "<thread-id>"  (thr_yid5rprxku here)
  3. In the desktop window open the thread, open the right panel (⌘J) → "Open new tab" (⌘T) → "Open browser" → type http://127.0.0.1:49333/ → Enter. Scripted here with repro/open-preview-in-thread.js, which finds the app window among the CDP pages by origin and needs only the two URLs substituted: 
    sed -e "s#__THREAD_URL__#http://localhost:<app-port>/projects/<project-id>/threads/<thread-id>#" \
    -e "s#__PREVIEW_URL__#http://127.0.0.1:49333/#" $R/open-preview-in-thread.js > /tmp/open-preview.js
doobie --connect 49222 -t 90 run /tmp/open-preview.js
    [
  "app target A351D19385A952E2ED087873C2E00216 (http://localhost:14158/)",
  "opened http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_yid5rprxku",
  "clicked button \"Show right panel\" (e102)",
  "clicked button \"Open new tab\" (e228)",
  "clicked button \"Open browser\" (e321)",
  "clicked textbox \"Address and search bar\" (e374)",
  "browser tab mounted: true"
]
  4. Observe a second CDP page target and a second renderer process: 
    $ curl -s http://127.0.0.1:49222/json/list   # after opening the tab
page  EE9EB179  http://127.0.0.1:49333/
page  A351D193  http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_yid5rprxku

$ ps -axo pid,ppid,rss,command | grep 'Electron Helper (Renderer)'
66587 66548 453520 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/node_modules/.pnpm/electron@41.7.0/node_modules/electron/dist/Electron.app/Contents/Frameworks/Electron Helper (Renderer).app/Contents/MacOS/Electron Helper (Renderer) --type=renderer --user-data-dir=/Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop --app-path=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/desktop --enable-sandbox --remote-debugging-port=49222 --lang=en-US --num-raster-threads=4 --enable-zero-copy --enable-gpu-memory-buffer-compositor-resources --enable-main-frame-before-activation --renderer-client-id=5 --time-ticks-at-unix-epoch=-1785397255777419 --launch-time-ticks=2192286856045 --shared-files --field-trial-handle=1718379636,r,1076711170803668596,4174251857620709702,262144 --enable-features=PdfUseShowSaveFilePicker,ScreenCaptureKitPickerScreen,ScreenCaptureKitStreamPickerSonoma --disable-features=DropInputEventsWhilePaintHolding,LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TimeoutHangingVideoCaptureStarts,TraceSiteInstanceGetProcessCreation --variations-seed-version --pseudonymization-salt-handle=1935764596,r,3157891776355157638,13858753825582910177,4 --trace-process-track-uuid=3190708990997080739 --seatbelt-client=59
74883 66548 101952 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/node_modules/.pnpm/electron@41.7.0/node_modules/electron/dist/Electron.app/Contents/Frameworks/Electron Helper (Renderer).app/Contents/MacOS/Electron Helper (Renderer) --type=renderer --user-data-dir=/Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop --app-path=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/desktop --enable-sandbox --remote-debugging-port=49222 --lang=en-US --num-raster-threads=4 --enable-zero-copy --enable-gpu-memory-buffer-compositor-resources --enable-main-frame-before-activation --renderer-client-id=6 --time-ticks-at-unix-epoch=-1785397255777419 --launch-time-ticks=2192393307580 --shared-files --field-trial-handle=1718379636,r,1076711170803668596,4174251857620709702,262144 --enable-features=PdfUseShowSaveFilePicker,ScreenCaptureKitPickerScreen,ScreenCaptureKitStreamPickerSonoma --disable-features=DropInputEventsWhilePaintHolding,LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TimeoutHangingVideoCaptureStarts,TraceSiteInstanceGetProcessCreation --variations-seed-version --pseudonymization-salt-handle=1935764596,r,3157891776355157638,13858753825582910177,4 --trace-process-track-uuid=3190708991934122588 --seatbelt-client=70
    bb desktop app DOM before archive
    Before archive: thread "2298 archive repro" in the sidebar, right panel showing the "bb#2298 animating preview" browser tab. The content area is empty in this DOM capture because the page lives in a native overlay.
    preview page target before archive
    The native view's own page (captured through its CDP target): HUD shows it is visible and counting rAF frames.
  5. Sample the preview target: visible, 120 rAF ticks in 2 s (preview-sample-1-before.json).
  6. Click the sidebar row's "Archive thread" button (this is archiveThreadAndChildrenAction; scripted with repro/archive-via-sidebar.js after sed "s#__APP_URL__#http://localhost:<app-port>#"). The thread leaves the sidebar, the app navigates to the root composer, and the "Archived … Undo" toast appears: 
    $ doobie --connect 49222 -t 60 run /tmp/archive.js
{
  "clicked": "button \"Archive thread\" (e53)",
  "url": "http://localhost:14158/",
  "archivedToast": true,
  "sidebarShowsNoThreads": false,
  "browserTabMounted": false
}
    app after archive
    After archive: sidebar shows "No threads" under both the project and the Threads section, root composer. (The "Archived … Undo" toast had already auto-dismissed when this capture was taken; the script above saw it.)
  7. Bug: the preview target and its renderer are still there, now hidden: 
    $ curl -s http://127.0.0.1:49222/json/list   # after UI archive
page  EE9EB179  http://127.0.0.1:49333/
page  A351D193  http://localhost:14158/

$ ps ... | grep 'Electron Helper (Renderer)'   # pid 74883 = the preview renderer, still alive
66587 66548 391520 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/node_modules/.pnpm/electron@41.7.0/node_modules/electron/dist/Electron.app/Contents/Frameworks/Electron Helper (Renderer).app/Contents/MacOS/Electron Helper (Renderer) --type=renderer --user-data-dir=/Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop --app-path=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/desktop --enable-sandbox --remote-debugging-port=49222 --lang=en-US --num-raster-threads=4 --enable-zero-copy --enable-gpu-memory-buffer-compositor-resources --enable-main-frame-before-activation --renderer-client-id=5 --time-ticks-at-unix-epoch=-1785397255777419 --launch-time-ticks=2192286856045 --shared-files --field-trial-handle=1718379636,r,1076711170803668596,4174251857620709702,262144 --enable-features=PdfUseShowSaveFilePicker,ScreenCaptureKitPickerScreen,ScreenCaptureKitStreamPickerSonoma --disable-features=DropInputEventsWhilePaintHolding,LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TimeoutHangingVideoCaptureStarts,TraceSiteInstanceGetProcessCreation --variations-seed-version --pseudonymization-salt-handle=1935764596,r,3157891776355157638,13858753825582910177,4 --trace-process-track-uuid=3190708990997080739 --seatbelt-client=59
74883 66548 110848 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/node_modules/.pnpm/electron@41.7.0/node_modules/electron/dist/Electron.app/Contents/Frameworks/Electron Helper (Renderer).app/Contents/MacOS/Electron Helper (Renderer) --type=renderer --user-data-dir=/Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop --app-path=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/desktop --enable-sandbox --remote-debugging-port=49222 --lang=en-US --num-raster-threads=4 --enable-zero-copy --enable-gpu-memory-buffer-compositor-resources --enable-main-frame-before-activation --renderer-client-id=6 --time-ticks-at-unix-epoch=-1785397255777419 --launch-time-ticks=2192393307580 --shared-files --field-trial-handle=1718379636,r,1076711170803668596,4174251857620709702,262144 --enable-features=PdfUseShowSaveFilePicker,ScreenCaptureKitPickerScreen,ScreenCaptureKitStreamPickerSonoma --disable-features=DropInputEventsWhilePaintHolding,LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TimeoutHangingVideoCaptureStarts,TraceSiteInstanceGetProcessCreation --variations-seed-version --pseudonymization-salt-handle=1935764596,r,3157891776355157638,13858753825582910177,4 --trace-process-track-uuid=3190708991934122588 --seatbelt-client=70

$ bash 2298/repro/sample-preview.sh ...   # preview-sample-2-after-archive.json
{
  "phase": "after archive (thread gone from sidebar)",
  "targetPresent": true,
  "targetId": "EE9EB17993C3C8029EC94C9E43C70075",
  "windowMs": 2000,
  "rafTicks": 0,
  "timerTicks": 3,
  "visibilityState": "hidden",
  "url": "http://127.0.0.1:49333/"
}
    preview page target after archive, hidden
    The same page, captured after archive: still loaded (rAF counter frozen at 5744), visibility: hidden. Nothing in the UI references it any more.
  8. Expected: the view is destroyed (target gone, renderer exits), as happens on delete. The persisted tab record is (correctly) kept: 
    $ bash $R/bbdev.sh thread tabs show thr_yid5rprxku --json
{
  "revision": 5,
  "tabs": [
    {
      "id": "thread-info:thread-info:none",
      "kind": "thread-info"
    },
    {
      "id": "git-diff:git-diff:none",
      "kind": "git-diff"
    },
    {
      "environmentId": "env_b257zvewfp",
      "id": "browser:kPqeY6kb8TvheykEiZeXs:env_b257zvewfp",
      "kind": "browser",
      "title": "bb#2298 animating preview",
      "url": "http://127.0.0.1:49333/"
    }
  ]
}
  9. Same leak via the wire path (how agents/CLI archive): unarchive, view the thread, run bash $R/bbdev.sh thread archive <thread-id>. The client only receives archived-changed: the app stays on the thread with a "Thread is archived" banner and the browser tab still mounted (assets/2298-07-app-after-cli-archive.png); navigating away in-app hides the view and, again, nothing destroys it (preview-sample-6-before-delete.json: present, hidden). Steps 9–11 are scripted in repro/wire-path.sh; its output from this run is repro/wire-path-run.txt.
  10. Control — delete: bash $R/bbdev.sh thread delete <thread-id> --yes sends thread-deleted, which the client handles: 
    $ curl -s http://127.0.0.1:49222/json/list   # after CLI delete
page  A351D193  http://localhost:14158/

$ ps -p 74883 -o pid,rss   # preview renderer
  PID    RSS            (no row: exited)

{"phase":"after CLI delete","targetPresent":false}

Preview-target samples (2 s windows, from sample-preview.sh)

PhaseCDP targetvisibilityStaterAF ticks10 ms timer ticks
before archive (preview tab visible)presentvisible120147
after archive (thread gone from sidebar)presenthidden03
archived thread opened from its URLpresentvisible120145
after CLI archive while the thread was being viewedpresentvisible120148
archived, app window reloaded at the root (side finding)presentvisible120149
archived, left via in-app navigation (just before delete)presenthidden02
after CLI deleteabsent–––

Row 5 (app window reloaded at the root via a full page.goto) is a side finding, see section 5: the reload wipes the renderer-side registry and the view stays visible with nothing owning it.

Repro files: 2298/repro/

5. Root cause

Ownership model. Commit ce006c6ea changed browser views from "destroyed when the deck unmounts" to "retained in a renderer-side registry, destroyed only on explicit teardown". The registry is a module-level map in the app renderer (apps/app/src/components/secondary-panel/browserViewVisibilityCoordinator.ts 65–133); BrowserTabContent registers on mount and explicitly does not detach on unmount:

// BrowserTabContent.tsx L579-L590, L661-L665
// Create (or re-attach to) the native view on mount and stream navigation
// state back. Unmount is not ownership teardown: switching threads unmounts
// the deck, but the native view is intentionally retained ...
    registerBrowserView({ environmentId, tabId, threadId });
...
      // The native view survives this unmount. Only explicit tab close/thread
      // deletion owns detach; unmount just disconnects this component's state
      // listener and forgets any stale visibility ownership.
      visibilityCoordinator?.release(tabId);

The explicit teardown sites are: tab removed from the open-tab list (apps/app/src/components/secondary-panel/BrowserTabDeck.tsx 63–85), thread delete from the UI (apps/app/src/components/thread/ThreadActionsProvider.tsx 265–280), and thread-deleted / environment-deleted broadcasts (apps/app/src/hooks/cache-owners/resource-route-owner.ts 69–82). Archive is in none of them.

// ThreadActionsProvider.tsx L265-L280 (delete)            // L333-L350 (archive)
onSuccess: () => {                                          archiveThreadAndChildrenMutateAsync({ id: thread.id }).then(
  destroyPersistedBrowserViewsForThread({                    (response) => {
    desktopBrowser: getDesktopBrowserApi(),                     ...
    threadId: thread.id,                                        syncNavigationAfterClose(
  });                                                            closePanesForThreads(response.archivedThreadIds),
  closeDialog();                                                  navigateAwayIfArchived,
  syncNavigationAfterClose(closePanesForThreads([thread.id]),   );
    () => navigateAwayIfViewing(thread));                       const toastId = ...      // <- no teardown anywhere
},

On the wire side, the server's archive service stops runtime work and closes the thread's terminals (apps/server/src/services/threads/thread-archive.ts 84–112) but browser views are a desktop-renderer concern, and the client's handler for archived-changed only invalidates queries (apps/app/src/hooks/cache-owners/realtime-cache-registry.ts 452–459). So both ways of archiving — the button and bb thread archive/SDK/automations — leave the registry entry and the native view untouched.

Why the symptom follows. When the pane closes, BrowserTabContent's layout-effect cleanup calls coordinator.hide(tabId) (apps/app/src/components/secondary-panel/BrowserTabContent.tsx 740–751), which is entry.view.setVisible(false) in the main process (apps/desktop/src/desktop-browser-view.ts 332–343). The WebContentsView, its webContents and renderer process remain (destroyEntry → webContents.close() runs only from detach, apps/desktop/src/desktop-browser-view.ts 715–731 / apps/desktop/src/desktop-browser-view.ts 821–823). The main process has no age/pressure policy and only drops views in releaseWindow on window close (apps/desktop/src/main.ts 1788–1794) and destroyAll on quit. Each archived thread that had an open preview therefore leaves one renderer process behind for the life of the window.

What the retained view costs (and does not). Electron 41's setVisible(false) marks the page hidden: in a standalone probe (repro/hidden-view-probe.cjs) and in the real app, a hidden retained view produced 0 rAF frames and ~1 timer tick per second, and webContents.close() ends the renderer process:

{"phase":"visible (setVisible(true))","windowMs":1000,"rafTicks":60,"timerTicks":79,"visibilityState":"visible","rendererPid":3192}
{"phase":"hidden via view.setVisible(false)","windowMs":1000,"rafTicks":0,"timerTicks":1,"visibilityState":"hidden","rendererPid":3192}
{"phase":"removed via contentView.removeChildView(view)","windowMs":1000,"rafTicks":0,"timerTicks":1,"visibilityState":"hidden","rendererPid":3192}
{"phase":"after webContents.close() (bb detach)","rendererPid":3192,"rendererProcessAlive":false,"webContentsDestroyed":true}

So the accumulation is process count, heap, and each renderer's retained compositor resources — not live animation. That matches "memory pressure looks unremarkable" better than the issue's compositing theory; the WindowServer/GPU CPU the reporter saw is more plausibly from the 4 live threads' visible or recently hidden previews.

Deeper issue (side finding, row 5 of the samples table). Because the only registry of views lives in renderer JS memory, a full reload of the app window (page.goto here; in the product, anything that reloads the renderer — dev HMR full reload, a renderer crash, ⌘R if enabled) wipes the registry while the main process keeps every view. Worse, React cleanups do not run on a hard navigation, so a view that was visible stays visible (row 5: visible, 120 rAF/2 s) at its last bounds with nothing owning it; after the reload neither archive nor delete can find it (destroyPersistedBrowserViewsForThread iterates the now-empty map). The durable fix for that is for the main process to own thread/environment ownership (attach already receives tabId; add threadId/environmentId) and to drop all views of a host window on did-start-navigation of the host webContents. It is out of scope for #2298 but the same mechanism.

6. Proposed fix (first principles)

Make archive symmetric with delete at both entry points. Applied in this worktree; diff in 2298/repro/proposed-fix.diff:

diff --git a/apps/app/src/components/thread/ThreadActionsProvider.tsx b/apps/app/src/components/thread/ThreadActionsProvider.tsx
index b5dfdf289..036ac0105 100644
--- a/apps/app/src/components/thread/ThreadActionsProvider.tsx
+++ b/apps/app/src/components/thread/ThreadActionsProvider.tsx
@@ -347,6 +347,17 @@ export function ThreadActionsProvider({
             closePanesForThreads(response.archivedThreadIds),
             navigateAwayIfArchived,
           );
+          // Archive is the ordinary way to finish with a thread: release the
+          // native browser views its tabs created, exactly as delete does.
+          // The tab metadata stays persisted, so unarchiving recreates the
+          // page lazily the same way reopening a thread already does.
+          const desktopBrowser = getDesktopBrowserApi();
+          for (const archivedThreadId of response.archivedThreadIds) {
+            destroyPersistedBrowserViewsForThread({
+              desktopBrowser,
+              threadId: archivedThreadId,
+            });
+          }
           const toastId = `thread-archived-${thread.id}`;
           appToast.success(
             <ArchivedThreadToastTitle
diff --git a/apps/app/src/hooks/cache-owners/resource-route-owner.ts b/apps/app/src/hooks/cache-owners/resource-route-owner.ts
index 70451ce16..6119f511c 100644
--- a/apps/app/src/hooks/cache-owners/resource-route-owner.ts
+++ b/apps/app/src/hooks/cache-owners/resource-route-owner.ts
@@ -38,6 +38,16 @@ function isDeletedThreadMessage(
   );
 }
 
+function isArchivedThreadMessage(
+  message: ChangedMessage,
+): message is ThreadChangedMessage & { id: string } {
+  return (
+    message.entity === "thread" &&
+    message.id !== undefined &&
+    message.changes.includes("archived-changed")
+  );
+}
+
 function isDeletedEnvironmentMessage(
   message: ChangedMessage,
 ): message is EnvironmentChangedMessage & { id: string } {
@@ -67,6 +77,17 @@ export function useDeletedResourceRouteOwner(): DeletedResourceRouteChangeHandle
       }
 
       if (!isDeletedThreadMessage(message)) {
+        // An archive that did not come from this window's own action (CLI,
+        // SDK, automation, another client) must still release the thread's
+        // native browser views; `archived-changed` is also emitted when a
+        // thread is unarchived, where there are no registered views to drop.
+        if (isArchivedThreadMessage(message)) {
+          destroyPersistedBrowserViewsForThread({
+            desktopBrowser: getDesktopBrowserApi(),
+            threadId: message.id,
+          });
+          return;
+        }
         if (isDeletedEnvironmentMessage(message)) {
           destroyPersistedBrowserViewsForEnvironment({
             desktopBrowser: getDesktopBrowserApi(),

7. PR review

No open pull request is linked to #2298 (checked gh pr list --search 2298 and the issue timeline).

8. Related issues

9. Appendix

CDP target lists

# baseline (app window only)
page  A351D193  http://localhost:14158/

# after opening the browser tab
page  EE9EB179  http://127.0.0.1:49333/
page  A351D193  http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_yid5rprxku

# after UI archive
page  EE9EB179  http://127.0.0.1:49333/
page  A351D193  http://localhost:14158/

# after CLI archive
page  EE9EB179  http://127.0.0.1:49333/
page  A351D193  http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_yid5rprxku

# after CLI delete
page  A351D193  http://localhost:14158/

Renderer processes

# after opening the browser tab (pid ppid rss-KB cmd)
66587 66548 453520 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/node_modules/.pnpm/electron@41.7.0/node_modules/electron/dist/Electron.app/Contents/Frameworks/Electron Helper (Renderer).app/Contents/MacOS/Electron Helper (Renderer) --type=renderer --user-data-dir=/Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop --app-path=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/desktop --enable-sandbox --remote-debugging-port=49222 --lang=en-US --num-raster-threads=4 --enable-zero-copy --enable-gpu-memory-buffer-compositor-resources --enable-main-frame-before-activation --renderer-client-id=5 --time-ticks-at-unix-epoch=-1785397255777419 --launch-time-ticks=2192286856045 --shared-files --field-trial-handle=1718379636,r,1076711170803668596,4174251857620709702,262144 --enable-features=PdfUseShowSaveFilePicker,ScreenCaptureKitPickerScreen,ScreenCaptureKitStreamPickerSonoma --disable-features=DropInputEventsWhilePaintHolding,LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TimeoutHangingVideoCaptureStarts,TraceSiteInstanceGetProcessCreation --variations-seed-version --pseudonymization-salt-handle=1935764596,r,3157891776355157638,13858753825582910177,4 --trace-process-track-uuid=3190708990997080739 --seatbelt-client=59
74883 66548 101952 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/node_modules/.pnpm/electron@41.7.0/node_modules/electron/dist/Electron.app/Contents/Frameworks/Electron Helper (Renderer).app/Contents/MacOS/Electron Helper (Renderer) --type=renderer --user-data-dir=/Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop --app-path=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/desktop --enable-sandbox --remote-debugging-port=49222 --lang=en-US --num-raster-threads=4 --enable-zero-copy --enable-gpu-memory-buffer-compositor-resources --enable-main-frame-before-activation --renderer-client-id=6 --time-ticks-at-unix-epoch=-1785397255777419 --launch-time-ticks=2192393307580 --shared-files --field-trial-handle=1718379636,r,1076711170803668596,4174251857620709702,262144 --enable-features=PdfUseShowSaveFilePicker,ScreenCaptureKitPickerScreen,ScreenCaptureKitStreamPickerSonoma --disable-features=DropInputEventsWhilePaintHolding,LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TimeoutHangingVideoCaptureStarts,TraceSiteInstanceGetProcessCreation --variations-seed-version --pseudonymization-salt-handle=1935764596,r,3157891776355157638,13858753825582910177,4 --trace-process-track-uuid=3190708991934122588 --seatbelt-client=70
# after UI archive
66587 66548 391520 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/node_modules/.pnpm/electron@41.7.0/node_modules/electron/dist/Electron.app/Contents/Frameworks/Electron Helper (Renderer).app/Contents/MacOS/Electron Helper (Renderer) --type=renderer --user-data-dir=/Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop --app-path=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/desktop --enable-sandbox --remote-debugging-port=49222 --lang=en-US --num-raster-threads=4 --enable-zero-copy --enable-gpu-memory-buffer-compositor-resources --enable-main-frame-before-activation --renderer-client-id=5 --time-ticks-at-unix-epoch=-1785397255777419 --launch-time-ticks=2192286856045 --shared-files --field-trial-handle=1718379636,r,1076711170803668596,4174251857620709702,262144 --enable-features=PdfUseShowSaveFilePicker,ScreenCaptureKitPickerScreen,ScreenCaptureKitStreamPickerSonoma --disable-features=DropInputEventsWhilePaintHolding,LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TimeoutHangingVideoCaptureStarts,TraceSiteInstanceGetProcessCreation --variations-seed-version --pseudonymization-salt-handle=1935764596,r,3157891776355157638,13858753825582910177,4 --trace-process-track-uuid=3190708990997080739 --seatbelt-client=59
74883 66548 110848 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/node_modules/.pnpm/electron@41.7.0/node_modules/electron/dist/Electron.app/Contents/Frameworks/Electron Helper (Renderer).app/Contents/MacOS/Electron Helper (Renderer) --type=renderer --user-data-dir=/Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop --app-path=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/desktop --enable-sandbox --remote-debugging-port=49222 --lang=en-US --num-raster-threads=4 --enable-zero-copy --enable-gpu-memory-buffer-compositor-resources --enable-main-frame-before-activation --renderer-client-id=6 --time-ticks-at-unix-epoch=-1785397255777419 --launch-time-ticks=2192393307580 --shared-files --field-trial-handle=1718379636,r,1076711170803668596,4174251857620709702,262144 --enable-features=PdfUseShowSaveFilePicker,ScreenCaptureKitPickerScreen,ScreenCaptureKitStreamPickerSonoma --disable-features=DropInputEventsWhilePaintHolding,LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TimeoutHangingVideoCaptureStarts,TraceSiteInstanceGetProcessCreation --variations-seed-version --pseudonymization-salt-handle=1935764596,r,3157891776355157638,13858753825582910177,4 --trace-process-track-uuid=3190708991934122588 --seatbelt-client=70
# after CLI delete
66587 66548 523936 /Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/node_modules/.pnpm/electron@41.7.0/node_modules/electron/dist/Electron.app/Contents/Frameworks/Electron Helper (Renderer).app/Contents/MacOS/Electron Helper (Renderer) --type=renderer --user-data-dir=/Users/USER/.bb-dev/bb-machines-HOST.getbb.app-checkouts-bb-.claude-worktrees-wf_846839f8-f8a-17-bd99a5562d1d/desktop --app-path=/Users/USER/.bb-machines/HOST.getbb.app/checkouts/bb/.claude/worktrees/wf_846839f8-f8a-17/apps/desktop --enable-sandbox --remote-debugging-port=49222 --lang=en-US --num-raster-threads=4 --enable-zero-copy --enable-gpu-memory-buffer-compositor-resources --enable-main-frame-before-activation --renderer-client-id=5 --time-ticks-at-unix-epoch=-1785397255777419 --launch-time-ticks=2192286856045 --shared-files --field-trial-handle=1718379636,r,1076711170803668596,4174251857620709702,262144 --enable-features=PdfUseShowSaveFilePicker,ScreenCaptureKitPickerScreen,ScreenCaptureKitStreamPickerSonoma --disable-features=DropInputEventsWhilePaintHolding,LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TimeoutHangingVideoCaptureStarts,TraceSiteInstanceGetProcessCreation --variations-seed-version --pseudonymization-salt-handle=1935764596,r,3157891776355157638,13858753825582910177,4 --trace-process-track-uuid=3190708990997080739 --seatbelt-client=59

thread_tabs after the run (sqlite3 on the instance DB)

thread_id|revision|archived_at|deleted_at|tabs_json
thr_kyzt8d4ieh|5|1787589937156||[{"id":"thread-info:thread-info:none","kind":"thread-info"},{"id":"git-diff:git-diff:none","kind":"git-diff"},{"environmentId":"env_b257zvewfp","id":"browser:tbiewCIKguIz0WEA3JgCq:env_b257zvewfp","kind":"browser","title":"bb#2298 animating preview","url":"http://127.0.0.1:49333/"}]

Archived thread reopened by URL (tab reachable)

archived thread opened by URL
Archived thread opened by its URL: "Thread is archived / Unarchive" banner and the "bb#2298 animating preview" browser tab mounted. Its Close button is hover-revealed and not visible in the pixels; the accessibility snapshot proves it exists (snapshot-archived-thread-open.txt: button "Close bb#2298 animating preview").
after CLI archive while viewing
After bb thread archive while viewing: the app stays on the thread with the tab mounted; the wire path never closes panes or views.

Commands run (abridged, in order; R = 2298/repro)

pnpm install --frozen-lockfile --prefer-offline && pnpm exec turbo run build
gh api repos/get-bb/bb/issues/2298 ; git fetch origin main ; git rev-parse origin/main   # == base
# code reading: rg destroyPersistedBrowserViewsForThread / archiveThreadAndChildrenAction ; git log -S ... ; git show ce006c6ea
Electron.app/Contents/MacOS/Electron $R/hidden-view-probe.cjs > $R/hidden-view-probe.out.jsonl
cp $R/ThreadActionsProvider.archive-browser-views.test.tsx apps/app/src/components/thread/
cd apps/app && pnpm exec vitest run src/components/thread/ThreadActionsProvider.archive-browser-views.test.tsx   # fails on base
scripts/bb-dev-app current ; eval "$(scripts/bb-dev-app env)"
CDP_PORT=49222 bash $R/launch-desktop.sh & ; python3 -m http.server 49333 --bind 127.0.0.1 --directory $R/page &
bash $R/make-scratch-repo.sh ; bash $R/bbdev.sh machine list --json ; curl -X POST $BB_SERVER_URL/api/v1/projects ...
bash $R/bbdev.sh thread spawn ... --prompt "Reply only with ok." --json
sed ... $R/open-preview-in-thread.js > /tmp/open-preview.js ; doobie --connect 49222 -t 90 run /tmp/open-preview.js
bash $R/capture-state.sh 49222 ... ; bash $R/sample-preview.sh ... ; doobie ... screenshot/snapshot of the app page
sed ... $R/archive-via-sidebar.js > /tmp/archive.js ; doobie --connect 49222 -t 60 run /tmp/archive.js   # UI archive -> target + renderer survive
bash $R/wire-path.sh <thread-id> <project-id> http://localhost:14158 49222 f8a-17   # unarchive / CLI archive / reload / delete
git apply $R/proposed-fix.diff ; vitest (repro + neighbours) ; turbo run typecheck --filter=@bb/app --force
bash $R/bbdev.sh thread spawn ... ; bash $R/fix-validation.sh <thread-id> <project-id> http://localhost:14158 49222 f8a-17 <bb.db>
pnpm dev:stop ; kill Electron/page-server ; rm -rf dev data dir ; lsof -nP -iTCP -sTCP:LISTEN   # cleanup

Output of wire-path.sh (steps 9–11) in this run

## 9a. unarchive via CLI (the thread is currently open in the app)
{
  "ok": true,
  "threadId": "thr_yid5rprxku"
}
banner=0 tab=1
## 9b. archive via CLI while the thread is being viewed
{
  "ok": true,
  "threadId": "thr_yid5rprxku",
  "archivedThreadIds": [
    "thr_yid5rprxku"
  ]
}
URL http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_yid5rprxku
53:      - status "Thread is archived" [ref=e269]:
55:        - generic [ref=e274]: Thread is archived
63:        - button "Close bb#2298 animating preview" [ref=e199]
page  EE9EB179  http://127.0.0.1:49333/
page  A351D193  http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_yid5rprxku
# pid ppid rss-KB (Electron Helper (Renderer) of f8a-17)
66587 66548 279280
74883 66548 102752
{
  "phase": "after CLI archive while the thread was being viewed",
  "targetPresent": true,
  "targetId": "EE9EB17993C3C8029EC94C9E43C70075",
  "windowMs": 2000,
  "rafTicks": 120,
  "timerTicks": 148,
  "visibilityState": "visible",
  "url": "http://127.0.0.1:49333/"
}
## 9c. side finding: full reload of the app window (page.goto to the root) orphans the view
URL http://localhost:14158/
{
  "phase": "archived, app window reloaded at the root (side finding)",
  "targetPresent": true,
  "targetId": "EE9EB17993C3C8029EC94C9E43C70075",
  "windowMs": 2000,
  "rafTicks": 120,
  "timerTicks": 149,
  "visibilityState": "visible",
  "url": "http://127.0.0.1:49333/"
}
## 9d. reopen the archived thread (re-registers the view), then leave it with an in-app navigation
{
  "afterOpen": {
    "url": "thread",
    "hasBrowserTab": true
  },
  "afterClientSideNav": {
    "url": "http://localhost:14158/",
    "hasBrowserTab": false,
    "hasSidebarThread": false
  }
}
{
  "phase": "archived, left via in-app navigation (just before delete)",
  "targetPresent": true,
  "targetId": "EE9EB17993C3C8029EC94C9E43C70075",
  "windowMs": 2000,
  "rafTicks": 0,
  "timerTicks": 2,
  "visibilityState": "hidden",
  "url": "http://127.0.0.1:49333/"
}
## 11. control: delete via CLI
{
  "ok": true,
  "threadId": "thr_yid5rprxku"
}
page  A351D193  http://localhost:14158/
# pid ppid rss-KB (Electron Helper (Renderer) of f8a-17)
66587 66548 523936
{"phase":"after CLI delete","targetPresent":false}

Output of fix-validation.sh (section 6) in this run

## open the preview tab in thr_kyzt8d4ieh
[
  "app target A351D19385A952E2ED087873C2E00216 (http://localhost:14158/)",
  "opened http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_kyzt8d4ieh",
  "clicked button \"Show right panel\" (e109)",
  "clicked button \"Open new tab\" (e238)",
  "clicked button \"Open browser\" (e324)",
  "clicked textbox \"Address and search bar\" (e377)",
  "browser tab mounted: true"
]
page  6B7557C9  http://127.0.0.1:49333/
page  A351D193  http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_kyzt8d4ieh
# pid ppid rss-KB (Electron Helper (Renderer) of f8a-17)
1801 66548 98272
66587 66548 552304
{
  "phase": "fix: before archive (preview tab visible)",
  "targetPresent": true,
  "targetId": "6B7557C915472289A17A987499D38433",
  "windowMs": 2000,
  "rafTicks": 120,
  "timerTicks": 161,
  "visibilityState": "visible",
  "url": "http://127.0.0.1:49333/"
}
## archive from the sidebar (archiveThreadAndChildrenAction)
{
  "clicked": "button \"Archive thread\" (e53)",
  "url": "http://localhost:14158/",
  "archivedToast": true,
  "sidebarShowsNoThreads": false,
  "browserTabMounted": false
}
page  A351D193  http://localhost:14158/
# pid ppid rss-KB (Electron Helper (Renderer) of f8a-17)
66587 66548 546528
{"phase":"fix: after archive","targetPresent":false}
## persisted tab record survives the archive
thread_id|revision|archived_at|deleted_at|tabs_json
thr_kyzt8d4ieh|5|1787589937156||[{"id":"thread-info:thread-info:none","kind":"thread-info"},{"id":"git-diff:git-diff:none","kind":"git-diff"},{"environmentId":"env_b257zvewfp","id":"browser:tbiewCIKguIz0WEA3JgCq:env_b257zvewfp","kind":"browser","title":"bb#2298 animating preview","url":"http://127.0.0.1:49333/"}]
## unarchive via CLI, reopen by URL: the page is recreated
{
  "ok": true,
  "threadId": "thr_kyzt8d4ieh"
}
URL http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_kyzt8d4ieh
85:        - button "Close bb#2298 animating preview" [ref=e214]
page  30EA1588  http://127.0.0.1:49333/
page  A351D193  http://localhost:14158/projects/proj_5srau8qsn9/threads/thr_kyzt8d4ieh
# pid ppid rss-KB (Electron Helper (Renderer) of f8a-17)
5156 66548 98720
66587 66548 582432
{
  "phase": "fix: after unarchive + reopen (page recreated)",
  "targetPresent": true,
  "targetId": "30EA1588676F5C3163D3C4CACC57A7C8",
  "windowMs": 2000,
  "rafTicks": 120,
  "timerTicks": 138,
  "visibilityState": "visible",
  "url": "http://127.0.0.1:49333/"
}

Note on isolation: a bare pnpm bb:dev without the scripts/bb-dev-app env variables resolves to the user's real server. In the first run of this investigation two such unprefixed calls happened (read-only or failed before doing anything); in the revised run every CLI call went through repro/bbdev.sh, which evaluates scripts/bb-dev-app env for the checkout it is run from before calling pnpm bb:dev.

Full artifacts: 2298/repro/ — probe script and outputs, repro test, fix diff, test/typecheck logs, CDP target and renderer snapshots, preview samples, UI snapshots, doobie driver scripts (open-preview-in-thread.js, archive-via-sidebar.js), helper scripts (launch-desktop.sh, bbdev.sh, make-scratch-repo.sh, capture-state.sh, snapshot-app.sh, sample-preview.sh, wire-path.sh, fix-validation.sh) and their outputs (*-run.txt).

10. Verification

An independent verifier re-ran this report from scratch in its own worktree (wf_846839f8-f8a-13 at 494f66526) and its own dev instance (app :16770 / server :24770 / daemon :32770). The unit repro failed 2/2 on base with the assertions shown in 4a, and passed 36/36 (repro + src/hooks/cache-owners/ + ThreadActionsProvider tests) with proposed-fix.diff applied; turbo typecheck @bb/app passed. Live: opening the preview produced a second CDP page target and renderer (~102 MB RSS); the sidebar "Archive thread" click left the target and renderer alive (hidden, 0 rAF / 2 s, ~109 MB RSS); opening the archived thread by URL showed the "Thread is archived" banner and the Close bb#2298 animating preview button in the accessibility snapshot; in-app navigation away left the view present and hidden; bb thread delete removed the target and ended the renderer. The verifier also checked every code claim against 494f66526 (line ranges, the two delete teardown sites, the missing archive ones, releaseWindow/destroyAll as the only main-process reclaim paths, archived-changed emitted on both archive and unarchive), confirmed origin/main == 494f66526 and that no PR is linked, and checked that all six referenced screenshots exist and match their captions. Verifier artifacts: 2298/verify/.

The verifier's findings and what changed in this revision: