macOS app: sent typed prompt reappears in composer after leaving and returning to thread

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

26.305.950 (863)

What subscription do you have?

No response

What platform is your computer?

macOS 26.3 (25D125), arm64

What issue are you seeing?

In Codex Desktop on macOS, after typing a prompt and pressing Enter to send it, leaving that thread and then returning causes the same prompt to reappear in the composer even though it was already submitted and is already present in the conversation.

This makes it look like there is an unsent duplicate draft of the message that just ran.

What steps can reproduce the bug?

1. Open a thread in Codex Desktop on macOS.
2. Type a normal text prompt into the composer.
3. Press Enter to send it.
4. Navigate away to another thread.
5. Return to the original thread.
6. Observe that the just-submitted prompt is back in the composer.

What is the expected behavior?

Once a prompt has been submitted, returning to the thread should not repopulate that same prompt into the composer unless there is actually unsent draft state to restore.

Additional information

• This appears related to, but not identical to, CXA-2863 (Message remains in composer after thread switch), which reports a Windows + voice-input path. This report is for typed text input on macOS.
• I did not find an open PR that appears to fix this behavior.