Codex App freezes / becomes Not Responding when opening image-heavy projects with many generated images

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

26.429.3425.0 x64 Installed from Microsoft Store. Process path: C:\Program Files\WindowsApps\OpenAI.Codex_26.429.3425.0_x64__2p2nqsd0c76g0\app\Codex.exe

What subscription do you have?

ChatGPT Team

What platform is your computer?

Microsoft Windows NT 10.0.19045.0 x64 Codex App installed from Microsoft Store. GPU: NVIDIA GeForce RTX 3060 Laptop GPU RAM: 32 GB

What issue are you seeing?

Codex App becomes extremely slow, freezes, or shows "Not Responding" when I open or continue working in a project/thread that contains many generated images.

The problematic project/thread contains a lot of image-generation work and generated image previews/assets. When I select that previous project, Codex may freeze for several minutes. During normal work, especially while Codex is "thinking" or when the thread/project UI is rendering previous generated images, the whole Codex window can become unresponsive.

This does not look like a normal model latency issue. The UI itself becomes stuck/unresponsive. The input box, project switching, scrolling, and window interactions can lag or stop responding.

In Task Manager / PowerShell, Codex runs as Electron/Chromium processes, including renderer and GPU subprocesses. Example process types observed:

Codex.exe --type=gpu-process
Codex.exe --type=renderer
Codex.exe --type=utility
codex.exe app-server --analytics-default-enabled

The freeze is much more noticeable in old projects/threads with many generated images than in lighter text-only work.

What steps can reproduce the bug?

1. Install Codex App from Microsoft Store on Windows.
2. Create or open a Codex project/thread where many images are generated over time.
3. Keep working in that same project/thread so the conversation/history contains many generated image previews/assets.
4. Close Codex or switch away from the project.
5. Reopen Codex.
6. Select the previous image-heavy project/thread.
7. Codex freezes, becomes extremely slow, or shows "Not Responding" for a long time.
8. Continue working in the same thread/project.
9. During "thinking" or while rendering the existing conversation/project history, the UI can freeze again.

The issue appears to correlate with the amount of generated image content in the thread/project.

What is the expected behavior?

Codex App should remain responsive when opening and working with projects/threads that contain many generated images.

The app should lazy-load or virtualize heavy image/history content so that old image-heavy threads do not freeze the entire UI.

Opening a previous project should not block the main UI for several minutes, and "thinking" should not make the desktop app become Not Responding.

Additional information

I tried increasing/fixing system virtual memory/pagefile first, but the issue still happens.

I also tried the common Windows DWM/MPO workaround:

reg add "HKLM\SOFTWARE\Microsoft\Windows\Dwm" /v OverlayTestMode /t REG_DWORD /d 5

After rebooting, this did not fix the freezing.

I also tried setting WebView2 browser arguments to disable GPU, but the Codex App appears to run as Electron/Chromium processes rather than msedgewebview2.exe processes, so those WebView2 flags did not affect Codex.

The process list still shows a Codex GPU process:

Codex.exe --type=gpu-process

This makes me suspect the freeze may be related to rendering/virtualization of image-heavy histories in the Codex Windows desktop app, possibly involving Electron/Chromium renderer/GPU behavior.

The uploaded thread id is:

019de42e-57ca-7b30-b935-935c6afa92b4

This thread/project contains a large amount of generated image work and is a good reproduction case for the UI freeze / Not Responding behavior.