[Copilot Agent Autopilot] VS Code Insiders completely freezes ("The window is not responding") when agent runs GitHub CLI commands

[ppiova]

Type: Performance Issue

Description

When using GitHub Copilot Agent in Autopilot mode (Preview), VS Code Insiders freezes completely with the system dialog:

"The window is not responding. You can reopen or close the window or keep waiting."

This happens specifically when the agent tries to interact with GitHub, for example when executing gh issue list --repo ... or similar GitHub CLI commands.

In the attached screenshot, the agent was working on task "INICIO DE PHASE 3 — US-019 (GENERACIÓN AUTOMÁTICA DE ARB)", reached the "Loading" state after running a GitHub command, and shortly after the entire VS Code window became unresponsive.

This issue occurred multiple times during the same Autopilot session (a plan with 9 tasks). The agent typically reaches around task 7/9, triggers the freeze, and I have to click "Reopen" several times. I was eventually able to reach task 9 after multiple restarts, but the experience is very unstable.

Steps to Reproduce

1. Open VS Code Insiders
2. Start a new Copilot Agent session in Autopilot (Preview) mode
3. Give it a multi-step task that involves GitHub interactions (reading issues, using gh CLI, etc.)
4. Let the agent run autonomously
5. The freeze occurs when the agent executes terminal commands that interact with GitHub

Expected Behavior

The agent should execute GitHub CLI commands without causing the entire VS Code window to hang.

Actual Behavior

VS Code becomes completely unresponsive ("The window is not responding") during GitHub-related operations in Autopilot mode.

Environment

• VS Code Version: 1.115.0-insider (user setup)
• Commit: 3d70aab
• Date: 2026-04-03T09:58:58-07:00
• Electron: 39.8.5
• OS: Windows_NT x64 10.0.26200 (Windows 11)
• GitHub Copilot Extension: [por favor agrega la versión exacta que tienes]
• Model used: Claude Opus 4.6 - High
• Repository: Working with ppiova/00-Agent-Opportunity (or similar)

Additional Context

• The freeze is triggered around task 7/9 in plans with many steps.
• It seems related to the agent running terminal commands via GitHub CLI (gh).
• This is happening consistently on Windows 11.

Logs (please include if possible)

• Go to View → Output
• Select GitHub Copilot, Copilot Agent, or Terminal from the dropdown
• Copy any errors or last lines that appear just before the freeze

Screenshot

(attached)

Workaround

Clicking "Reopen" several times eventually allows the session to continue, but it is unreliable and interrupts long-running Autopilot tasks.

This appears to be a stability issue with Copilot Agent + GitHub CLI integration on the latest VS Code Insiders on Windows 11.

VS Code version: Code - Insiders 1.115.0-insider (3d70aab, 2026-04-03T09:58:58-07:00)
OS version: Windows_NT x64 10.0.26200
Modes:

System Info

Item	Value
CPUs	AMD Ryzen AI 9 365 w/ Radeon 880M (20 x 1996)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x1002, DEVICE=0x150e [AMD Radeon(TM) Graphics], DRIVER_VENDOR=AMD, DRIVER_VERSION=32.0.11026.4001 ACTIVE GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.7309 Machine model name: Machine model version: direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	31.29GB (8.35GB free)
Process Argv	--crash-reporter-id 808ee221-d76c-4ebe-8542-9de2f8c93fea
Screen Reader	no
VM	0%

Process Info

CPU %	Mem MB	   PID	Process
    0	   147	  4116	code-insiders
    0	    24	  5980	   crashpad-handler
    0	    42	  9368	   utility-network-service
    1	   228	 20956	   gpu-process
    0	   138	 32124	file-watcher [8]
    0	   134	 41364	shared-process
    0	   169	 43180	pty-host
    5	   119	  5352	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    12	  8852	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x824 --server 0x87c
    0	    10	 11572	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x6e4 --server 0x734
    0	   148	 11832	     "C:\Program Files\PowerShell\7\pwsh.exe" -NoProfile -ExecutionPolicy Bypass -Command "Import-Module 'c:\Users\ppiov\.vscode-insiders\extensions\ms-vscode.powershell-2025.4.0\modules\PowerShellEditorServices\PowerShellEditorServices.psd1'; Start-EditorServices -HostName 'Visual Studio Code Host' -HostProfileId 'Microsoft.VSCode' -HostVersion '2025.4.0' -BundledModulesPath 'c:\Users\ppiov\.vscode-insiders\extensions\ms-vscode.powershell-2025.4.0\modules' -EnableConsoleRepl -StartupBanner \"PowerShell Extension v2025.4.0
Copyright (c) Microsoft Corporation.

https://aka.ms/vscode-powershell
Type 'help' to get help.
\" -LogLevel 'Warning' -LogPath 'c:\Users\ppiov\AppData\Roaming\Code - Insiders\logs\20260403T171212\window3\exthost\ms-vscode.powershell' -SessionDetailsPath 'c:\Users\ppiov\AppData\Roaming\Code - Insiders\User\globalStorage\ms-vscode.powershell\sessions\PSES-VSCode-4116-907209.json' -FeatureFlags @() "
    0	    12	 11908	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 72 --height 11 --signal 0x7d8 --server 0x574
    0	   113	 15068	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    10	 16820	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x774 --server 0x794
    0	    85	 17972	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	   125	 20972	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    12	 23896	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x92c --server 0x934
    5	   119	 24020	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    10	 25360	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x5dc --server 0x644
    0	   128	 25808	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	   123	 26444	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    12	 31516	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x808 --server 0x8d4
    0	   113	 35252	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    10	 39528	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x69c --server 0x570
    0	   122	 39708	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	   116	 40512	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    12	 41004	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x78c --server 0x81c
    0	    13	 41628	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x8d0 --server 0x78c
    0	    82	 45272	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    12	 45740	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 108 --height 12 --signal 0x958 --server 0x608
    0	    10	 46692	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x5d8 --server 0x644
    0	   131	 47784	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    81	 48308	     "C:\Program Files\PowerShell\7\pwsh.exe" -noexit -command "try { . \"c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\out\vs\workbench\contrib\terminal\common\scripts\shellIntegration.ps1\" } catch {}"
    0	    10	 48704	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x6e8 --server 0x6e0
    0	    12	 51128	     "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\node_modules\node-pty\build\Release\conpty\OpenConsole.exe" --headless --width 80 --height 30 --signal 0x9ac --server 0x9a4
    1	   495	 45060	extension-host [8]
    0	     4	 40948	     c:\GitHubRepos\00-Agent-Opportunity\.venv\Scripts\python.exe c:\Users\ppiov\.vscode-insiders\extensions\ms-python.python-2026.4.0-win32-x64\python_files\run-jedi-language-server.py
    0	     7	 21672	       C:\Windows\system32\conhost.exe 0x4
    0	    59	 50896	       c:\GitHubRepos\00-Agent-Opportunity\.venv\Scripts\python.exe c:\Users\ppiov\.vscode-insiders\extensions\ms-python.python-2026.4.0-win32-x64\python_files\run-jedi-language-server.py
    0	    12	 45504	     c:\Users\ppiov\.vscode-insiders\extensions\ms-python.vscode-python-envs-1.26.0-win32-x64\python-env-tools\bin\pet.exe server
    0	     7	  4800	       C:\Windows\system32\conhost.exe 0x4
    0	   114	 50440	     "C:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\Code - Insiders.exe" "c:\Users\ppiov\AppData\Local\Programs\Microsoft VS Code Insiders\3d70aab9a4\resources\app\extensions\json-language-features\server\dist\node\jsonServerMain" --node-ipc --clientProcessId=45060
    0	   121	 51780	     electron-nodejs (server-node.js)
    3	   393	 50340	window [8] (Welcome - 00-Agent-Opportunity - Visual Studio Code - Insiders)

Workspace Info

|  Window (Welcome - 00-Agent-Opportunity - Visual Studio Code - Insiders)
|    Folder (00-Agent-Opportunity): 9851 files
|      File types: pyc(3681) py(3629) xml(416) txt(165) log(154) h(86)
|                  typed(64) pyi(45) exe(31) pyd(28)
|      Conf files: github-actions(4) copilot-instructions.md(1)
|                  github-prompts-dir(1);

Extensions (7)

Extension	Author (truncated)	Version
claude-code	Ant	2.1.90
copilot-chat	Git	0.43.2026040304
vscode-github-actions	git	0.31.2
debugpy	ms-	2025.18.0
python	ms-	2026.4.0
vscode-python-envs	ms-	1.26.0
powershell	ms-	2025.4.0

A/B Experiments

vsliv368:30146709
pythonvspyt551cf:31249598
nativeloc1:31118317
dwcopilot:31158714
dwoutputs:31242946
copilot_t_ci:31333650
g012b348:31231168
pythonrdcb7:31268811
pythonpcpt1:31399616
6518g693:31302842
b6b4d950:31327385
6abeh943:31336334
envsactivate1:31349248
editstats-enabled:31346256
cloudbuttont:31366566
3efgi100_wstrepl:31403338
839jf696:31457053
use-responses-api:31390341
je187915:31454425
cp_cls_t_966_ss:31454198
inlinechat_v2_hd992725:31445440
4je02754:31455664
8hhj4413:31478653
ge8j1254_inline_auto_hint_haiku:31488153
38bie571_auto:31426784
cp_cls_c_1081:31454833
conptydll_true:31485575
ia-use-proxy-models-svc:31446143
e9c30283:31453065
test_treatment2:31471001
idci7584:31454084
nes_chat_context_disabled:31451402
e3e4d672:31454087
showingstats:31457201
ei9d7968:31462942
534a6447:31478742
7ef87755:31455235
nes-extended-on:31455475
f860i809:31458078
jc933416:31462667
89g7j272:31480197
7e884298:31462391
bg_compact_t:31477450
t-some:31466503
7e187181:31482583
cpptoolsoff-v2:31475362
i2gc6536:31472020
30450953:31486770
h08i8180_copy:31475366
23c7c724:31488001
client_tst_t:31486874
po_split_t:31488387
ddid_t:31478204
file_logging_enabled:31485059
61f49681:31488289
fixed-ctrl-prompt-cache:31487637
pro_large_t:31484703
41e7a136_t:31485218

[ppiova]

Hi @alexr00 ,

Update: I removed the GitHub MCP server completely and then re-added it. After that, the Copilot Agent in Autopilot mode completed the 9/9 tasks without any freezes or repeated "Reopen" prompts.

The issue appears to have been related to a corrupted GitHub MCP state/configuration.

Thanks!

[DuoLocal]

Confirming this exact issue on my setup.

Environment:

• VS Code Insiders (latest as of 2026-04-06)
• Windows 11 Pro 10.0.26120
• GitHub Copilot Chat (release channel)
• Models used: GPT 5.4 (xhigh reasoning), Claude Opus 4.6

Symptoms:

• "The window is not responding" dialog appears during Copilot Chat agent streaming
• Freeze occurs specifically when the AI is actively generating and the chat panel is rendering streamed content
• Terminal processes crash with exit code 1 (pwsh.exe -ExecutionPolicy Bypass -NoProfile)
• CPU and memory are NOT elevated when it freezes — it's a renderer/main thread block, not a resource issue

What we tried (none of these resolved it):

• Disabled hardware acceleration (argv.json)
• Increased V8 heap to 8GB (--max-old-space-size=8192)
• Uninstalled all extensions except Copilot Chat + theme
• Disabled all Copilot experimental features (temporalContext, thinkingTool, codesearch, nextEditSuggestions, languageContext, etc.)
• Set files.watcherExclude and search.exclude for node_modules, dist, .git, etc.
• Set search.followSymlinks: false
• Disabled formatOnSave, formatOnPaste, formatOnType
• Switched autoSave to afterDelay: 1000
• Reduced terminal scrollback to defaults (1000/100)
• Reduced chat.agent.maxRequests to 30
• Set diffEditor.maxComputationTime: 5000 (was unlimited)
• Set editor.largeFileOptimizations: true
• Switched from pre-release to release Copilot Chat extension
• Cleaned VS Code cached state

Conclusion: This is a platform-level bug in the chat webview renderer, not addressable through user configuration. The freeze correlates with the volume of streamed content — higher reasoning levels (more tokens) trigger it more reliably.

[alexr00]

Starting by assigning to @justschen since you've been investigating perf recently.

[ryansmccoy]

Adding a data point from stable VS Code 1.115.0 (Windows 11, Copilot Chat 0.43.0) — this isn't Insiders-only.

@DuoLocal's analysis matches my experience exactly — mitigations don't help. I also tried:

• Reducing to a single-folder workspace (rules out multi-root)
• Disabling git integration, shell integration, file watchers
• Clearing Copilot session state
• Removing and re-adding GitHub MCP server + resetting MCP cache across all workspace storage DBs (@ppiova's workaround did not fix it for me)

One additional observation that might help @justschen narrow it down:

The same command succeeds or freezes depending on who runs it:

Who runs it	Result
Me, typing in the integrated terminal	✅ Completes instantly
Copilot Agent via terminal tool	❌ "The window is not responding"

Example command:

gh issue view 2241 --json title,body,labels,state,milestone 2>&1 | Out-String -Width 500

So the freeze isn't the command or its output — it's something in the agent's terminal integration path (output capture → tool result serialization → chat rendering). This aligns with @DuoLocal's conclusion that it's a renderer/main-thread block rather than a resource issue.

Narrowing it down

I ran a series of tests to isolate the trigger:

Agent runs this	Output size	Result
echo 1	tiny	✅ Works
Get-Date	small	✅ Works
gh issue list --limit 1 --json number	medium	✅ Works
gh issue view 2234 --json body	1.3 KB	✅ Works
gh issue view 2231 --json body	1.9 KB	✅ Works
gh issue view 2240 --json body	2.7 KB	✅ Works
gh issue view 2245 --json body	3.5 KB	❌ Freezes
gh issue view 2241 --json body	4.8 KB	❌ Freezes
gh issue view 2239 --json body	5.0 KB	❌ Freezes

Threshold: between 2.7 KB and 3.5 KB of terminal output. Tested systematically across 7 different GitHub issues with increasing body sizes. The same commands run manually in the integrated terminal complete instantly — only the agent terminal tool path freezes.

This confirms @DuoLocal's observation: the freeze correlates with output volume. The threshold appears to be around ~3 KB of terminal output passed through the agent tool result → chat renderer pipeline.

[michael-rabe]

The same problem occurs in the command line.
GitHub issues are encoded differently than terminal output.
This apparently led to an infinite loop when parsing terminal output to JSON.
The following command prompt works perfectly for me and bypasses the usual approach of using terminal output by reading a temporary file instead.

The following is the first shot of a working agent instruction (on a windows system)

## ⚠️ GitHub CLI (gh) Terminal Safety (CRITICAL)

**Problem:** VS Code 1.115+ freezes ("The window is not responding") when the

Copilot agent runs `gh` commands that produce large JSON output directly in

the integrated terminal. The RunInTerminalTool output analyzer hangs on the

combination of multi-kilobyte JSON payloads and encoding mismatches

(gh emits UTF-8, PowerShell 5.1 defaults to Codepage 850).


**Rule — Never capture `gh` JSON output through the terminal.** Always pipe it

to a temp file and read the file separately:


powershell

# ✅ CORRECT — Step 1: pipe to file, only "OK" goes to terminal

gh issue view 83 --json title,body,labels,assignees 2>$null | Out-File "$env:TEMP\gh_result.json" -Encoding utf8; "OK"

# ✅ CORRECT — Step 2: use the read_file tool (NOT Get-Content) to read the file

# read_file on: C:\Users\<user>\AppData\Local\Temp\gh_result.json


# ✅ CORRECT — small scalar outputs are safe

gh pr list --json number,title --limit 5 --jq ".[].number"


# ❌ WRONG — large JSON to terminal will freeze VS Code

gh issue view 83 --json title,body,labels,assignees


# ❌ WRONG — reading the temp file into terminal causes the same freeze!

Get-Content "$env:TEMP\gh_result.json" -Raw

cat "$env:TEMP\gh_result.json"

type "$env:TEMP\gh_result.json"


**When is this needed?**

- Any `gh` command that returns more than ~2 KB of JSON output

- Any `gh issue view` or `gh pr view` with `--json body` (issue/PR bodies

  can be 10–50 KB)

- Any `gh api` call returning lists or detailed objects



**Safe without redirect:**

- `gh auth status`, `gh repo view --json name`, `gh pr list --json number`

  (small outputs under ~1 KB)

[tolotrasamuel]

I am facing the same issue on macos

[smilearchery]

Same freeze on macOS (Stable 1.115.0) — root cause traced to RegExp.test in shell integration

Description

Experiencing the same complete UI freeze ("The window is not responding") on VS Code Stable 1.115.0 on macOS. The freeze occurs when Copilot Agent executes a burst of terminal commands (test, git diff, git add, git commit, gh CLI), especially when terminal output contains multi-line content with CJK (Chinese) characters.

I was able to capture a CPU sample and main process logs while the window was frozen, which pinpoint the root cause to a RegExp.test() call inside sLo / _waitForIdle on the renderer main thread — likely catastrophic backtracking on shell integration ANSI sequences.

Root Cause Analysis

Main process log (main.log):

23:22:28 [error] CodeWindow: detected unresponsive
23:22:43 [error] [uncaught exception in main]: UnresponsiveSampleError: from window with ID 1 belonging to process with pid 41115
    at RegExp.test (<anonymous>)
    at workbench.desktop.main.js:3963:4685
    at Array.some (<anonymous>)
    at sLo (workbench.desktop.main.js:3963:4675)
    at Ire._waitForIdle (workbench.desktop.main.js:3914:29140)
    at async Ire._startMonitoring (workbench.desktop.main.js:3914:20445)

All 14 unresponsive samples show the identical RegExp.test → sLo → _waitForIdle call stack, confirming the renderer main thread is stuck in a regex evaluation loop.

Terminal log shows 6× repeated warnings just before the freeze:

23:19:54 [warning] Shell integration failed to add capabilities within 10 seconds
23:20:01 [warning] Shell integration failed to add capabilities within 10 seconds
23:20:07 [warning] Shell integration failed to add capabilities within 10 seconds
23:20:13 [warning] Shell integration failed to add capabilities within 10 seconds
23:20:19 [warning] Shell integration failed to add capabilities within 10 seconds
23:20:30 [warning] Shell integration failed to add capabilities within 10 seconds

CPU sample (sample 41115 3) confirms the renderer process at 101% CPU (state: R running), with the main thread entirely inside V8 JIT / regex execution:

2198 Thread_2378409  DispatchQueue_1: com.apple.main-thread
  + 2198 ElectronMain → v8::Message::GetLineNumber → ... → cppgc::internal::ExplicitManagementImpl::Resize

All 2198 samples (100%) are on the main thread — no concurrency, pure main-thread block.

Trigger Pattern

The freeze was triggered by Copilot Agent rapidly executing terminal commands via RunInTerminalTool with the rich execute strategy. The specific sequence:

1. pnpm test:run ...
2. git diff --stat
3. git diff -- file.json
4. git status --short
5. git add ... (8 files)
6. git commit -m "fix(issue-18): ..." — multi-line commit message with Chinese characters (~600 bytes)
7. gh-app.sh ... pr view 43 ...

The commit message at step 6 contained multi-line CJK text, which likely caused the shell integration regex to backtrack catastrophically.

Process Info at Freeze Time

CPU %   Mem MB    PID  Process
100.7      643  41115  Code Helper (Renderer) — FROZEN, state R
  1.3      440  41137  Code Helper (Plugin) — extension host
  1.2      390  42186  Code Helper (Plugin) — tsserver
  0.7       86  41111  Code Helper (GPU)
  0.4      137  41106  Code (main process)
  0.2       59  41135  Code Helper (utility)
  0.2       54  41134  Code Helper (utility)
  0.1       40  41138  Code Helper (utility)
  0.0       12  41221  codex app-server (OpenAI extension)

Environment

Item	Value
VS Code	1.115.0 (Stable)
Commit	41dd792
Date	2026-04-07T22:04:57Z
Electron	39.8.5
OS	macOS 15.7.5 (24G624)
CPU	Intel Core i7-8850H @ 2.60GHz
Memory	32 GB

Extensions

Extension	Version
github.copilot-chat	0.43.0
openai.chatgpt	26.409.20454
anthropic.claude-code	2.1.101
vscodevim.vim	1.32.4
esbenp.prettier-vscode	12.4.0
ms-python.python	2026.4.0
+ 30 others	(Java, C++, Jupyter, etc.)

[tolotrasam]

I made a PR about it #309232