[Windows][Desktop] Window height stretches far beyond the monitor after minimizing and restoring with Alt+Tab (dual monitor, extended display set as primary)

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

26.901.1978.0 (Microsoft Store package OpenAI.Codex_26.901.1978.0_x64__2p2nqsd0c76g0)

What subscription do you have?

N/A

What platform is your computer?

Windows 11 x64, laptop + one external monitor. The external monitor is set as the primary display, and the Codex window is opened on it.

What issue are you seeing?

After minimizing the Codex window and switching back to it with Alt+Tab, the window's HEIGHT becomes abnormally tall — it extends far beyond the bottom edge of the monitor, while its WIDTH stays unchanged. The window looks stretched vertically and no longer fits on screen.

Workarounds: clicking the Maximize button, or manually dragging/resizing the window back inside the screen bounds. This is required after every occurrence.

Steps to reproduce

1. Use a laptop + external monitor setup with the external monitor set as the primary display.
2. Open the Codex window on the primary (external) monitor.
3. Minimize the Codex window.
4. Switch back to Codex with Alt+Tab.
5. Observe: the window height is now much larger than the monitor height (width unchanged); most of the window is off-screen below.

Reproducibility: 100% — happens on every minimize + Alt+Tab cycle.

This has been present for several months across multiple app updates.

What is the expected behavior?

The restored window keeps its previous size and position and is fully visible on its monitor.

Related issues

• #34023 (window overflows screen bounds on multi-monitor 200% DPI setup)
• #25826 (maximized window spills onto adjacent monitors)

These are related but not identical: this bug is specifically about a vertical height explosion after a minimize + Alt+Tab restore, with unchanged width.

Start by reproducing the minimize and Alt+Tab cycle on Windows 11 with an external primary monitor, as described in the issue. Trace the desktop window restoration path and compare the saved and restored bounds; done means the window retains its prior size and position and remains fully visible after every cycle.