[BUG] ASCII characters corrupted content

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 a few minutes of normal usage, the terminal is unusable, it starts to show some weird corrupted symbols, then it spreads to all the text in the terminal.

It happen in almost any terminal, the default one in mac, Ghostty, Ghostty integrated in vs code, etc.

Seems to go away sometimes, selecting al the text in the window, and deselecting. Other workaround, is to create a new terminal tab in vs code, and changing to it, and go back. Sames apply to Ghostty.

A preview of what happens.
PD: Sorry for my english.
<img width="956" height="536" alt="Image" src="https://github.com/user-attachments/assets/9657a4c1-dad9-4d96-9028-47e8a13cdd05" />

What Should Happen?

Show the terminal and its content normally

Error Messages/Logs

Steps to Reproduce

1. Open a new session
2. Use for a few minutes
3. Weird symbols starts to show, first in animated sections, then all the text is corrupted

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.150

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

MacOS: Tahoe 26.3
VS Code: 1.121.0
Ghostty: 1.3.1
Claude Code: 2.1.150