Windows ChatGPT/Codex app UI turns black when hovering menu — fixed by --disable-gpu-compositing

What version of the Codex App are you using (From “About Codex” dialog)?

Version 26.903.61454

What subscription do you have?

Plus

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

The new ChatGPT/Codex Windows desktop app has a rendering issue where part of the interface turns black, preventing me from accessing the ChatGPT/Codex selector/menu.

Repairing the app temporarily fixes the issue. After a repair, the application launches and renders normally, but as soon as I move my mouse over the ChatGPT/Codex menu area, the interface turns black again.

I tested several Chromium/Electron launch flags and was able to isolate the issue to GPU compositing.

What steps can reproduce the bug?

Feedback ID: no-active-thread-01a0880e-a9f3-75d2-8b4b-0f01c62ffffc

What is the expected behavior?

The ChatGPT/Codex menu should render normally when hovered or opened, allowing me to switch between ChatGPT and Codex.

Additional information

Workaround discovered:

Launching the application with:

--disable-gpu-compositing

completely resolves the issue.

I isolated this by testing the following:

Full workaround — works:
Powershell:
Get-Process ChatGPT,Codex -ErrorAction SilentlyContinue | Stop-Process -Force

$pkg = Get-AppxPackage -Name 'OpenAI.Codex' | Sort-Object Version -Descending | Select-Object -First 1

Start-Process (Join-Path $pkg.InstallLocation 'app\ChatGPT.exe') -ArgumentList '--disable-gpu','--disable-gpu-compositing','--disable-direct-composition','--disable-features=EnableTransparentHwndEnlargement,CalculateNativeWinOcclusion','--force-color-profile=srgb'

I then removed the GPU-disabling flags while keeping the other rendering flags. The black-screen issue returned.

I added back only --disable-gpu-compositing, and the application worked normally.

Finally, I tested only:
Powershell:
Get-Process ChatGPT,Codex -ErrorAction SilentlyContinue | Stop-Process -Force

$pkg = Get-AppxPackage -Name 'OpenAI.Codex' | Sort-Object Version -Descending | Select-Object -First 1

Start-Process (Join-Path $pkg.InstallLocation 'app\ChatGPT.exe') -ArgumentList '--disable-gpu-compositing'

This also works normally. I can hover the menu, open it, and access Codex without the interface turning black.

This appears to isolate the problem specifically to the application's GPU compositing/rendering path rather than corrupted application data.

System information:

OS: Windows 11
GPU: NVIDIA GeForce RTX 5090
Display: 4K / 240 Hz
Installation: Microsoft Store/AppX version of the new ChatGPT/Codex application

Additional information:

Windows' Repair option causes the app to render normally on the first launch, but the problem immediately returns when hovering over the affected menu. --disable-gpu-compositing has been consistently successful and does not require --disable-gpu. Launching the app with the following .bat results in a successful launch with UI rendering normal:
@echo off
powershell -NoProfile -WindowStyle Hidden -Command "Get-Process ChatGPT,Codex -ErrorAction SilentlyContinue | Stop-Process -Force; $pkg = Get-AppxPackage -Name 'OpenAI.Codex' | Sort-Object Version -Descending | Select-Object -First 1; Start-Process (Join-Path $pkg.InstallLocation 'app\ChatGPT.exe') -ArgumentList '--disable-gpu-compositing'"

Start by reproducing the hover failure in the Windows Store/AppX app through the ChatGPT.exe entry point on the reported Windows and NVIDIA setup. Compare the menu rendering with and without --disable-gpu-compositing, then trace the affected desktop rendering path. Done means the ChatGPT/Codex selector remains usable when hovered without requiring the workaround.