Windows Codex app (Local mode): “Open in Cursor” button disappears after first message

<img width="1788" height="1299" alt="Image" src="https://github.com/user-attachments/assets/fb776800-39b3-4dc2-85e5-bfa14ce7408f" />
<img width="1746" height="1296" alt="Image" src="https://github.com/user-attachments/assets/dfeee0a4-a1de-4769-8325-8bb26e04f9f1" />

Product: Codex app for Windows
Version: 26.406.3494
Plan: ChatGPT Plus (Codex included)
OS: Windows 11
IDE: Cursor 3.0.16
Mode: Local

In a new Local-mode thread, the “Open in Cursor” button appears in the top-right initially, but disappears immediately after sending the first message.

Steps to reproduce:

Open the Codex app on Windows

Start a new thread in Local mode

Confirm “Open in Cursor” is visible in the top-right

Send any message

Observe the “Open in Cursor” button disappears

Expected result:
“Open in Cursor” remains available after the first message so the thread/workspace can be opened in Cursor at any time.

Actual result:
The “Open in Cursor” button disappears right after sending the first prompt and does not return.

Frequency / Repro rate:
100% reproducible (every time)

Troubleshooting attempted:

Windows app Repair performed (no change)

Attachments:

Screenshots showing button present before first message and missing after first message