Select All Copies Only First 100 Lines in Code Viewer

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

Expanded Codex usage, GPT-5.5 Thinking

What subscription do you have?

Plus

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

In the Codex desktop app code viewer, Select All appears to select the entire file, but Copy only copies a small part of the file.

Both Ctrl + A and Select All with mouse return the same 100 line of code depending on where on the scroll you are.

This happened with a .lua file around 591 lines long. The full file looked selected in the viewer, but when pasted elsewhere, only the first small portion of the file was copied.

This makes it hard to copy complete generated/edited files into external tools such as Roblox Studio.

What steps can reproduce the bug?

1. Open a long code file in the Codex desktop app code viewer. In my case it was a .lua file around 591 lines.
2. Use Select All/Ctrl + A in the code viewer.
3. Copy the selected all text.
4. Paste into another editor or application.
5. Notice that only a about 100 lines of code is pasted, even though the full file appeared selected.

What is the expected behavior?

_No response_

Additional information

_No response_