Windows app becomes unresponsive when attaching and using a ~3.6 MB JPEG image

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

26.313.5234.0

What subscription do you have?

Unknown

What platform is your computer?

Windows

What issue are you seeing?

In Codex Desktop on Windows, attaching an image and then using it in the conversation can cause the app to become unresponsive (Not Responding).

In my case, the attached file was a JPEG around 3.6 MB. This is much smaller than the oversized-attachment case reported in #13508, so this does not appear to require an extremely large file.

Steps to Reproduce

1. Open Codex Desktop on Windows.
2. Attach a JPEG image to the thread.
3. The image size in my case was about 3.6 MB.
4. Use the attached image in the conversation / send the prompt after attaching it.
5. Observe that the app becomes unresponsive and Windows shows Not Responding.

Expected Behavior

• The app should either upload/process the image successfully, or fail gracefully with an error.
• A normal-sized JPEG attachment should not freeze the app.
• The thread should remain usable even if image handling fails.

What do you see instead?

The app stops responding after the image is attached and used in the conversation.

Additional information

• Image type: JPEG
• Approximate size: 3.6 MB
• Symptom: Codex Desktop becomes unresponsive / Not Responding
• Related but not identical issue: #13508 reports a 134 MB PNG causing a 413 and thread freeze. This report is for a much smaller JPEG still causing an app hang.