[Windows Desktop] Pro chat turn completes with no assistant message or error

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

26.803.81509

What subscription do you have?

ChatGPT Pro

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

In ChatGPT mode on Windows Desktop, prompts sent with the selector set to Pro can terminate silently. The UI returns to idle immediately, with no assistant response, retry control, or error banner.

A controlled reproduction after fully restarting the app showed:

Non-Pro control at 2026-08-14 05:35:20.839Z: responded successfully in approximately 0.7 seconds.

Pro attempt at 2026-08-14 05:39:00.527Z: the persisted turn was immediately reported as completed with error=null, but contained only the user message and no assistant message.

It remained unchanged after five minutes.

Local read-only diagnostics found no authentication, network, firewall, timeout, HTTP 401/403/429/5xx, or application crash correlated with the attempt.

Steps that reproduce the bug:

1. Fully close and reopen ChatGPT Desktop on Windows.
2. Open an isolated ChatGPT chat.
3. With a non-Pro selector, send: Reply exactly: OK-NONPRO
4. Confirm that it responds normally.
5. Change the selector to Pro.
6. Send: Reply exactly: OK-PRO
7. Observe that the UI returns to idle without an assistant response, retry option, or error.
8. Wait at least five minutes; no response appears.

What steps can reproduce the bug?

Feedback ID: no-active-thread-019ffed1-083b-7de0-b2ed-5f96c63dcb33

What is the expected behavior?

The Pro turn should eventually create an assistant response, or the UI should display an explicit actionable error/retry state. A turn should not be marked completed while containing only the user message.

Additional information

Desktop package identity: OpenAI.Codex_26.803.10989.0.

Possibly related cross-platform context:

• On the web, the Pro option is not shown.
• On iPhone, the account shows Pro as the current plan, but Pro cannot be selected in chats.

A private OpenAI Support case is already escalated for the related entitlement/synchronization investigation. This public issue is limited to the reproducible Windows Desktop behavior.

No source file or test is identified. Start by reproducing the Windows Desktop Pro flow and tracing how the selector, persisted turn, and completion state are handled. Done means a Pro turn produces an assistant response or an explicit actionable error/retry state, rather than completing with only the user message.