Windows app: official pinned taskbar icon does not restore hidden main window after close-to-background #17205

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

26.406.3494.0

What subscription do you have?

Pro

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

On Windows, closing the visible Codex window leaves the app running in the background, but clicking the official pinned taskbar icon does not restore the hidden main window.

The only reliable recovery is to end the Codex processes in Task Manager and cold-start the app again.

I verified this after restoring the taskbar pin to the official packaged app target, so this does not appear to be a bad shortcut/pin configuration.

What steps can reproduce the bug?

1. Launch Codex from the official pinned taskbar icon.
2. Confirm the main Codex window is visible.
3. Close the visible Codex window normally.
4. Confirm Codex remains alive in the background.
5. Click the same official pinned taskbar icon again.
6. Observe that no visible Codex window returns.

What is the expected behavior?

Clicking the official pinned taskbar icon should restore the existing hidden Codex window or otherwise show a visible Codex UI without requiring Task Manager cleanup.

Additional information

• Package full name: OpenAI.Codex_26.406.3494.0_x64__2p2nqsd0c76g0
• Package family: OpenAI.Codex_2p2nqsd0c76g0
• Official pinned shortcut used:
  C:\Users\Nilhan.dev\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\Codex.lnk

Fresh local repro evidence:

• Before close, the main top-level window existed as:
  • handle: 0x290672
  • title: Codex
  • class: Chrome_WidgetWin_1
  • visible: true
• After close, the same main window handle 0x290672 still existed but visible=false
• After clicking the official pinned taskbar shortcut, the same main window handle 0x290672 still existed and still had visible=false
• Visible main window count after taskbar relaunch: 0

So the app is not fully gone; the primary window remains alive but hidden, and the official taskbar relaunch path does not bring it back.

I also checked a few adjacent paths:

• Launching through shell:AppsFolder\\OpenAI.Codex_2p2nqsd0c76g0!App showed the same behavior
• Current logs during this repro did not show the cache/router errors from some other Windows launch failures

Local bundle inspection suggests the tray button path explicitly calls window visibility logic, while second-instance relaunch appears to route through deep-link argument handling. That may explain why the hidden window survives but is not restored by a plain relaunch.

This feels related to the current Windows background/stale-process family, but narrower than the existing reports because the key failure here is:

official pinned taskbar icon -> existing hidden main window is not restored

I have a local evidence pack with screenshots and a JSON capture of the window state before close, after close, and after taskbar relaunch if that would help.