Windows MSIX: opening the in-app Browser pane crashes the GPU process (exit 101457950); app then cannot relaunch until MSIX re-add (reinstall loop)

### Preflight Checklist

- [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) and this hasn't been reported yet
- [x] This is a single bug report (please file separate reports for different bugs)
- [x] I am using the latest version of Claude Code

### What's Wrong?

## Environment
- Claude desktop app 1.24012.9 (MSIX `Claude_1.24012.9.0_x64__pzs8sxrjxfjjc`), bundled Claude Code CLI 2.1.219
- Windows 11 Enterprise 10.0.26200
- GPU: NVIDIA GeForce RTX 3090 Ti — reproduces on driver 591.86 AND after a clean install of Studio 610.62
- Dual monitor, 144 Hz, 150% scaling, 128 GB RAM
- Timestamps below are local (UTC-3), 2026-07-24 → 2026-07-26

## Summary
Deterministic trigger, found empirically: whenever a chat task opens the built-in Browser pane, the Chromium GPU process crashes and takes every window down. The main process survives as a zombie (window-less claude.exe processes keep running). After that the app cannot be launched at all — clicking the icon does nothing. The only recovery is re-running "Claude Setup.exe" (258 MB download + in-place AddPackage). 7+ forced reinstalls in 3 days.

Sessions that never open the Browser pane stay up for many hours; opening it kills the app shortly after.

## Evidence

main.log — identical exit code before every death:
```
2026-07-26 05:48:17 [info] GPU process gone: { type: 'GPU', reason: 'crashed', exitCode: 101457950, serviceName: 'GPU' } (x3 burst, app died)
2026-07-26 06:20:01 [info] GPU process gone: { ... exitCode: 101457950 ... } (x3 burst, app died — driver 610.62 already active)
2026-07-26 06:08:22 [info] GPU process gone: { ... exitCode: 34 ... } (single, survivable — GPU process relaunched)
```

logs/gpu-info.json (since ~Jun 21) shows acceleration already degraded to software fallback on an RTX 3090 Ti: `gl=none`, `inProcessGpu: true`, `dx12FeatureLevel: "Not supported"`, all overlays NONE.

No WER / Application-event-log crash entries at all — processes die without Windows error reports, so the failure is silent.

Relaunch failure: Event Viewer (AppXDeploymentServer/Operational) shows each launch attempt triggering `RegisterByPackageFullName` with `ForceTargetApplicationShutdownOption,RepairAppRegistrationOption`; the operations complete successfully but the app remains unlaunchable. AppModel-Runtime package status flaps 0x2/0x80002 until a full re-add. Killing the zombie processes and deleting GPUCache/DawnGraphiteCache/DawnWebGPUCache does NOT restore launchability; only Claude Setup.exe (AddPackage with ForceApplicationShutdownOption,ForceUpdateFromAnyVersion) does.

ClaudeSetup.log — every installer run reports a conflicting packaged service it cannot remove, even elevated:
```
WARNING: CoworkVMService already exists (potential conflict)
Removing conflicting CoworkVMService...
WARNING: failed to remove conflicting service: could not open CoworkVMService: Access is denied.
Windows rejected data-preserving removal for Claude_1.24012.9.0_x64__pzs8sxrjxfjjc (0x80073CFA, requires developer mode); relying on in-place update
```
CoworkVMService: WIN32_PACKAGED_PROCESS, LocalSystem, AUTO_START, binPath inside the versioned package folder (...\WindowsApps\Claude_1.24012.9.0_x64__pzs8sxrjxfjjc\app\resources\cowork-svc.exe).

## Steps to reproduce
1. Windows MSIX install; open the desktop app.
2. In any session, run a task that opens the built-in Browser pane (preview/browse).
3. GPU process crashes (exit 101457950); all windows close; claude.exe processes remain running.
4. Try to reopen from the Start menu — nothing happens (repair registrations logged, no window).
5. Recover only by re-running Claude Setup.exe.

## Workarounds tried
- Clean NVIDIA driver update 591.86 → 610.62 (Studio): no effect — same exit code afterwards
- Killing zombie claude.exe processes: app still won't launch
- Deleting GPU/shader caches (GPUCache, DawnGraphiteCache, DawnWebGPUCache): no effect
- Re-registering the package (`Add-AppxPackage -Register -DisableDevelopmentMode -ForceApplicationShutdown AppxManifest.xml`): being tested
- Launching `Claude.exe --disable-gpu`: being tested
- Reinstall via Claude Setup.exe: works every time (only known fix)

## Probably related
- #72878 (main process killed at loader time on every launch after first successful run)
- #75337 (update leaves package in deferred-registration loop; cowork-svc keeps package files locked)

## Impact
7+ forced reinstalls in 3 days (258 MB each), active work sessions killed mid-task, Browser pane unusable.

Happy to provide full logs (main.log, ClaudeSetup.log, Event Viewer exports) on request.

### What Should Happen?

Expected behavior: The Browser pane opens; even if the GPU process dies, Chromium falls back to software rendering and the app keeps running — and the app can always be relaunched from the Start menu.

Actual behavior: The GPU process crash (exit 101457950) closes every window, leaves window-less claude.exe zombies, and the app cannot be relaunched by any means until the MSIX package is re-added by running Claude Setup.exe again (258 MB download each time).

### Error Messages/Logs

```shell
[claude-bug-logs.zip](https://github.com/user-attachments/files/30390331/claude-bug-logs.zip)
```

### Steps to Reproduce

1. Use a Windows 11 machine with an NVIDIA GPU. Reproduced on: Windows 11 Enterprise 10.0.26200, GeForce RTX 3090 Ti (both on driver 591.86 and after a clean install of Studio 610.62), dual monitor 144 Hz at 150% scaling.

2. Install the Claude desktop app with "Claude Setup.exe" (app 1.24012.9, MSIX package Claude_1.24012.9.0_x64__pzs8sxrjxfjjc) and sign in.

3. Control observation: open any session and work normally WITHOUT using the built-in Browser pane. The app stays up for many hours with no crash.

4. Now give the assistant any task that opens the built-in Browser pane (web preview / browse step, e.g. "open a page in the browser and take a screenshot"). No repo or code is needed - the trigger is the pane itself.

5. Within seconds to a few minutes of the pane spinning up, the GPU process crashes and every app window closes at once. main.log records:
GPU process gone: { type: 'GPU', reason: 'crashed', exitCode: 101457950, serviceName: 'GPU' }
Same exit code in all 8 fatal occurrences on Jul 25-26. No WER / Windows Application-log crash entry is written (silent failure).

6. Open Task Manager: several claude.exe processes are still running (window-less zombies).

7. Click the Claude icon in the Start menu: nothing opens - no window, no error dialog. Event Viewer (AppXDeploymentServer/Operational) logs RegisterByPackageFullName with RepairAppRegistrationOption on each attempt; the operations succeed but the app remains unlaunchable. Killing the zombie processes and deleting GPUCache/DawnGraphiteCache/DawnWebGPUCache does not restore launchability.

8. Re-run "Claude Setup.exe": it downloads the MSIX again and performs an in-place AddPackage (ForceApplicationShutdownOption + ForceUpdateFromAnyVersion); the app opens again.

9. Repeat step 4 - the crash and the unlaunchable state reproduce (8 forced reinstalls on this machine between Jul 25-26).

Sanitized logs attached (claude-bug-logs.zip): full crash list with context excerpts, installer log covering all reinstalls, AppX deployment events, the app's GPU snapshot (acceleration degraded to software fallback since ~Jun 21), and the CoworkVMService configuration (the packaged service the installer reports it cannot remove: "could not open CoworkVMService: Access is denied").

### Claude Model

Not sure / Multiple models

### Is this a regression?

Yes, this worked in a previous version

### Last Working Version

_No response_

### Claude Code Version

2.1.219 (Claude Code)

### Platform

Anthropic API

### Operating System

Windows

### Terminal/Shell

PowerShell

### Additional Information

[claude-bug-logs.zip](https://github.com/user-attachments/files/30390333/claude-bug-logs.zip)

Start by reproducing the Browser pane trigger on the stated Windows MSIX installation and inspect main.log, gpu-info.json, ClaudeSetup.log, and the AppXDeploymentServer events. Done means the Browser pane no longer causes the GPU process and windows to crash, and the app can be relaunched without rerunning Claude Setup.exe.

Written by the indexing model from the issue text.