Windows Codex app fullscreen button rendering issue; F11 works

Environment

• OS: Windows 10.0.19045
• Codex app version: 26.601.2237.0
• Install source: Microsoft Store
• PowerShell: 7.6.0
• Package status: Ok
• codex.exe signature: Valid / OpenAI OpCo, LLC

Issue

Clicking the fullscreen button with the mouse causes a rendering/fullscreen failure. Using F11 to enter or exit fullscreen works normally.

Steps to reproduce

1. Open the Codex Windows app.
2. Click the fullscreen button with the mouse.
3. Observe rendering/fullscreen error.
4. Press F11 instead.
5. F11 fullscreen works correctly.

Expected behavior

The mouse fullscreen button should behave the same as F11.

Actual behavior

The mouse fullscreen button fails or causes rendering issues, while F11 works.

Tried

• Restarted Codex completely
• Checked Microsoft Store / winget update: no update available
• Ran Windows app repair
• Reinstalled Codex
• Cleared only Codex cache/GPUCache/Dawn cache folders
• Verified package status and executable signature

Workaround

Use F11.

Notes

No logs are attached because local logs and session transcripts may contain sensitive workspace or account information.