[BUG] Terminal display becomes garbled and unreadable after using Claude Code

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 using Claude Code for a session, the terminal output becomes visually corrupted - characters render as fragmented/garbled glyphs (see attached screenshot). Text is partially missing, characters appear cut off vertically, and the output is effectively unreadable. The terminal state remains dirty even after Claude Code exits, requiring a terminal restart or reset to recover.

Claude Terminal Windows
<img width="967" height="253" alt="Image" src="https://github.com/user-attachments/assets/940d135e-97d0-4af2-927d-9fc279b8b465" />
<img width="880" height="385" alt="Image" src="https://github.com/user-attachments/assets/f8544db0-a507-4217-a402-db33dff95b0d" />

Other Terminal Windows

<img width="848" height="417" alt="Image" src="https://github.com/user-attachments/assets/b2d182dd-5f19-4b85-9a24-f4b0727d3e9f" />

What Should Happen?

Terminal output should remain cleanly rendered during and after Claude Code sessions. Exiting Claude Code should leave the terminal in a clean, usable state with no residual rendering artifacts.

Error Messages/Logs

Steps to Reproduce

1. Open a terminal session (zsh on macOS).
2. Start claude and use it for a typical session (tool calls, streaming output, etc.).
3. Observe the terminal output gradually becoming garbled — characters appear truncated/fragmented.
4. Exit Claude Code; terminal remains in the corrupted state until manually reset.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.141

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

• OS: macOS (Darwin 25.4.0)
• Shell: zsh
• Working in a project directory with an active git repo