CodeWindow unresponsive when ask cursor code something in agent layout

[sueja (Jiang Shen)]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

When I work in Cursor’s Agent layout, the window becomes unresponsive whenever the assistant applies file modifications. The same prompts complete normally in the Editor layout. Logs show repeated “CodeWindow: detected unresponsive,” and a CPU trace reveals the renderer main thread stuck in heavy JS execution (large v8.callFunction/AsyncTask Run blocks, long ResponseBodyLoader::OnStateChange events, extensive Blink layout/paint work, plus significant V8 GC time). The unresponsiveness happens only during Agent-driven file rewrites; plain runs in the Editor layout do not trigger it.

Steps to Reproduce

1. Open Agent Layout
2. ask code something
3. when step to show code diff the window is unresponsive

Screenshots / Screen Recordings

Operating System

MacOS

Current Cursor Version (Menu → About Cursor → Copy)

Version: 2.0.69 (Universal)
VSCode Version: 1.99.3
Commit: 63fcac100bd5d5749f2a98aa47d65f6eca61db30
Date: 2025-11-07T18:21:29.650Z
Electron: 37.7.0
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Darwin arm64 23.6.0

For AI issues: which model did you use?

Auto

For AI issues: add Request ID with privacy disabled

01887f21-1955-47d4-bc3b-7437c135f588

Additional Information

main.log
2025-11-11 11:47:22.000 [info] [CursorProclistService] Native module loaded successfully
2025-11-11 11:47:22.044 [info] updateURL https://api2.cursor.sh/updates/api/update/darwin-universal/cursor/2.0.69/07478485a49b1e9a7dd63ccb5a743274ec9e8950ebc2eb6bff0469a602aa432a/stable
2025-11-11 11:47:22.046 [info] update#setState idle
2025-11-11 11:47:22.641 [info] [Tray] getMacOSIconPath: hasNotifications: false
2025-11-11 11:47:24.722 [warning] [BrowserViewMainService] Cannot flush storage data: browser view not created for window 1
2025-11-11 11:47:24.727 [warning] [BrowserViewMainService] Cannot set visibility: browser view not created for window 1
2025-11-11 11:47:25.491 [info] Extension host with pid 22530 exited with code: 0, signal: unknown.
2025-11-11 11:47:29.562 [warning] [BrowserViewMainService] Cannot execute JavaScript: browser view not created for window 1
2025-11-11 11:47:33.527 [info] [CursorProclistService] Config disabled feature
2025-11-11 11:47:52.048 [info] update#setState checking for updates
2025-11-11 11:47:53.235 [info] UpdateService onUpdateNotAvailable()
2025-11-11 11:47:53.236 [info] update#setState idle
2025-11-11 11:48:09.676 [info] [Tray] getMacOSIconPath: hasNotifications: true
2025-11-11 11:48:14.345 [info] [Tray] getMacOSIconPath: hasNotifications: false
2025-11-11 11:48:26.266 [warning] TracingService: dropping unsupported envelope
2025-11-11 11:49:54.794 [info] [Tray] getMacOSIconPath: hasNotifications: true
2025-11-11 11:49:57.342 [info] [Tray] getMacOSIconPath: hasNotifications: false
2025-11-11 11:53:26.270 [warning] TracingService: dropping unsupported envelope
2025-11-11 11:54:26.323 [error] CodeWindow: detected unresponsive
2025-11-11 11:54:28.734 [error] CodeWindow unresponsive samples:
<1>
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4858:26038
at Array.flatMap ()
at C (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4858:26030)
at Object.fn (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4858:26649)
at bIa (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:30076)
at _it (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:29830)
at FLt (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:31457)
at TBd (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:32859)
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:32319
at iG (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:31635)
at EBd (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:32312)
at iG (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:31646)
at YP (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:24452)
at eMt (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:441:22369)
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4857:36894
at p_o.invokeFunction (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:5895:960)
at dp (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4857:36810)
at t5c (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4858:40118)
at w (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4858:42953)
at MutationObserver. (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4858:44509)
<1>
at NLt (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:30453)
at Ee (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:25085)
at bE (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:28579)
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:34604
at wo (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:27299)
at Object.fn (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:34557)
at bIa (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:30076)
at _it (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:29830)
at vt (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:24886)
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:34548
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:36276
at wo (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:27299)
at V (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:36269)
at get children (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4857:36986)
at Object.fn (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:34613)
at bIa (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:30076)
at _it (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:29830)
at Ee (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:25219)
at bE (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:28579)
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:34604
at wo (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:27299)
at Object.fn (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:34557)
at bIa (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:30076)
at _it (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:29830)
at vt (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:24886)
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:34548
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:36276
at wo (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:27246)
at V (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:36269)
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4857:36910
at mIa (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:27803)
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4857:36902
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:441:22402
at YP.a (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:24406)
at iG (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:31635)
at YP (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:276:24452)
at eMt (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:441:22369)
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4857:36894
at p_o.invokeFunction (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:5895:960)
at dp (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4857:36810)
at t5c (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4858:40118)
at w (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4858:42953)
at MutationObserver. (vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:4858:44509)
Total Samples: 2
For full overview of the unresponsive period, capture cpu profile via Runtime debugging · microsoft/vscode Wiki · GitHub
2025-11-11 11:54:29.851 [info] Extension host with pid 22871 exited with code: 0, signal: unknown.
2025-11-11 11:54:33.237 [warning] [BrowserViewMainService] Cannot execute JavaScript: browser view not created for window 2

Does this stop you from using Cursor

Yes - Cursor is unusable

[condor (Condor (Tee))]

hi @sueja and thank you for the detailed bug report.

We may need more information to reproduce the issue:

• Does it occur on all file types or only specific files?
• Does it show only in existing chats or also in new chats?
• Please check Help > Open Process Explorer and post here a screenshot.
• Do you have any processes running in terminal within Cursor?
• Does this also occur on a new project? (would indicate large chat storage)
• Does this occur when you run with extensions disabled? cursor --disable-extensions

[sueja (Jiang Shen)]

• it occur on all file types，ex py, package.json、pyproject.toml，once agent load some code has changed

• existing chats or also in new chats => both

• Do you have any processes running in terminal within Cursor? => no

• Does this also occur on a new project => yes

• Does this occur when you run with extensions disabled? cursor --disable-extensions => yes

  

I have try run cursor with cursor --disable-extensions but it still occur, and try to delete the folder ~/Library/Application Support/Cursor and start new cursor without import any setting and extensions, but it still occur

[sueja (Jiang Shen)]

20251111T114721.zip (84.4 KB) file is cursor log, i can’t find any related. errors

[condor (Condor (Tee))]

From the screenshot it looks like it is related to language server (TypeScript,…) which is always enabled. Will check with the team.