[BUG] Characters rendering incorrectly in chat interface after recent update

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?

Since a recent update, characters in Claude Code's chat interface are not rendering correctly. Special characters, accented letters (e.g. à, è, ì, ò, ù) and punctuation appear malformed or missing in Claude's responses.

Expected: All characters display correctly
Actual: Characters appear corrupted/malformed
OS: macOS 25.4.0

What Should Happen?

Expected: All characters display correctly
Actual: Characters appear corrupted/malformed
OS: macOS 25.4.0

Error Messages/Logs

Steps to Reproduce

Steps to reproduce:

1. Open Claude Code
2. Start a conversation
3. Characters in the response text appear incorrectly rendered

Claude Model

Sonnet (default)

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.1.145 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_