Codex Windows App: Ctrl+V image paste becomes very slow after first paste, while drag-and-drop is fast

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

OpenAI.Codex 26.527.7698.0 PackageFullName observed in logs: OpenAI.Codex_26.527.7698.0_x64__2p2nqsd0c76g0

What subscription do you have?

ChatGPT Pro

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64 Windows 11 25H2, build 26200.8457

What issue are you seeing?

In Codex Desktop on Windows, pasting images via Ctrl+V is very slow. The first image paste in a fresh conversation can be relatively faster, but subsequent image pastes often take about 10+ seconds before the image attachment/preview finishes.

This appears specific to Codex's image clipboard paste path. Drag-and-drop image upload is fast, and other apps paste images normally. The Codex input box still accepts typed text while the image paste is delayed, so the whole app/computer is not frozen.

What steps can reproduce the bug?

1. Open a fresh Codex conversation.
2. Open Windows Paint.
3. Draw a tiny mark/dot.
4. Press Ctrl+A, then Ctrl+C in Paint.
5. Go back to Codex and press Ctrl+V.
6. Repeat the same image paste multiple times in the same Codex conversation.

Observed result:

• The first paste in a fresh conversation can be faster.
• Later Ctrl+V image pastes often take about 10+ seconds.
• Dragging the same image file into Codex is fast.

What is the expected behavior?

Ctrl+V image paste should attach quickly, similar to drag-and-drop image upload. A tiny image copied from Paint should appear as an attachment/preview without a 10+ second delay.

Additional information

Troubleshooting already tried:

• Upgraded from Windows 10 to Windows 11 25H2.
• Reset Codex App from Windows app settings.
• Tried Paint-copy of a tiny image, so it is not specific to browser/screenshot source.
• Disabled third-party startup items / tried clean-start style troubleshooting.
• Compared with another computer using the same OpenAI/Codex account; that computer does not reproduce the issue.
• Drag-and-drop continues to work normally.
• Other applications can paste images normally.
• CPU does not obviously spike during the delay.

This looks like Codex may be waiting on a clipboard/image attachment processing timeout after the first paste.