[BUG] Plan mode acceptance UI is haunted

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?

Plan mode has created a rather long plan for me. This caused the plan to exceed the size of my terminal window, resulting in annoying visual glitches. However, the plan wasn't quite correct, so I needed to ask claude to change it. As soon as my change writeup exceeded a certain length, the screen started flickering violently and the options kept changing between 1 and 2 (the edit is 3) without me hitting any keys. See the attached screen capture (to be clear, I am hitting no keys here):

https://github.com/user-attachments/assets/f61b2e84-3cd3-43fd-b998-da64f3e05646

What Should Happen?

Bust the ghosts - let me complain about the plan to claude.

Error Messages/Logs

Steps to Reproduce

I'm not entirely sure - I suspect any sufficiently large plan will do it.

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.0.60 (Claude Code)

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Other

Additional Information

Terminal is gnome terminal as shipped with Ubuntu.