[BUG] /usage text unselectable after Edit tool diff block; prior diff component breaks mouse selection

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

After Claude performs a file edit (displaying an Edit tool diff block with line numbers and highlighted changed lines), within the /usage panel rendered below it becomes impossible to highlight or copy with the mouse. Attempting to click-drag select text in the /usage output either selects nothing or skips the target section entirely. The skipped sections align with the formatting for a similar copy on the screen "underneath" the /usage overlay.

What Should Happen?

The mouse highlighting of content in an overlay window like /usage should not depend on the content on the original window.

Error Messages/Logs

Steps to Reproduce

1. Ask Claude to edit an on-disk file — this triggers an Edit tool result showing a diff view with line numbers and colored changed/added lines.
2. Run /usage.
3. Attempt to mouse-select the whole text in the /usage output.

Result: Text selection is broken. The /usage content cannot be highlighted or copied.
Expected: Text in /usage is normally selectable, as it is when no preceding diff block is present.

Claude Model

Sonnet (default)

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

v2.1.193

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

I checked some prior similar issues such as:

• #70556: a new selection overlay blocks copying entirely (TUI, Linux)
• #63676: can't selectively copy from assistant responses, only full-message copy works
• #61021: text selection + copy stopped working in VS Code terminal

But they didn't seem to apply, though some were similar.