[BUG] --chrome-native-host crashes on Windows (Bun panic)

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?

The Chrome native messaging host crashes immediately on launch, preventing Claude Code from connecting to the Claude in Chrome extension. The crash is a Bun internal assertion failure, not a user code issue.

Environment

• Claude Code: 2.1.110
• OS: Windows 11 Enterprise 10.0.26200
• Bun: 1.3.13 (bundled)
• Node: v24.14.1
• Chrome extension ID: fcoeoabgfenejglbffodgkkbkcdhcgfn

What Should Happen?

Expected behavior

Native host starts successfully and Chrome extension connects to Claude Code.

Error Messages/Logs

Observed behavior

  Native host panics on startup:

  [Claude Chrome Native Host] Initializing...
  [Claude Chrome Native Host] Creating socket listener: \\.\pipe\claude-mcp-browser-bridge-<user>

  panic(main thread): Internal assertion failure
  oh no: Bun has crashed. This indicates a bug in Bun, not your code.

  Crash report: https://bun.report/1.3.13/e_1edb020dkggggEkgggC+pu/M+ky6G6lnsoBq3+loB__utw15CA0eNrzzCtJLcpLzFFILC5OLSrJzM9TSEvMzCktSgUAiSkKPg

Steps to Reproduce

Steps to reproduce

1. Install Claude in Chrome extension
2. Run /chrome in Claude Code to register the native messaging host
3. Restart Chrome
4. Attempt to connect — tabs_context_mcp returns "Browser extension is not connected"
5. Run the native host manually to see the crash:

"C:\Users\<user>\.local\bin\claude.exe" --chrome-native-host

Claude Model

Opus

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

Claude Code: 2.1.110

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

Notes

• Registry key at HKCU\Software\Google\Chrome\NativeMessagingHosts\com.anthropic.claude_code_browser_extension is correctly set
• Native messaging manifest and batch file are present and correctly configured
• Extension works standalone (responds to queries in its popup)
• Claude Code is up to date (2.1.110 is latest)