[BUG] Conversation history duplicates when resizing terminal window vertically

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?

When the Claude Code terminal window is not in fullscreen and I resize it
vertically (drag to make it taller or shorter), the conversation history
entries get duplicated visually — sometimes appearing 10+ times.

The duplicated entries do not go away after resizing back or scrolling.
The only workaround is to close and reopen the window.

This does NOT happen in fullscreen mode — only when the window is in a
smaller/windowed state.

Steps to Reproduce:

1. Open Claude Code in a non-fullscreen window
2. Make the window smaller
3. Drag the window edge to resize it vertically (up or down)
4. Observe conversation history duplicating repeatedly

What Should Happen?

Conversation history renders once and stays stable during window resize.

Error Messages/Logs

Conversation history entries are duplicated multiple times on vertical
  resize and do not reset without closing the window.

Steps to Reproduce

1. Open Claude Code in a non-fullscreen (windowed) state
2. Make the window smaller
3. Drag the window edge vertically (up or down) to resize
4. Observe conversation history duplicating repeatedly

Note: This does NOT occur in fullscreen mode. Duplicates do not go away
after resizing back — only closing and reopening the window resets it.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.110 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_