Chrome Native Host crashes on Windows - Bun internal assertion failure

Description

The Chrome Native Host (claude --chrome-native-host) crashes immediately on startup on Windows 11 with a Bun internal assertion failure. This prevents the Claude in Chrome extension from connecting to Claude Code.

The extension is properly installed and configured (settings panel loads, approved sites visible), but the MCP bridge never establishes because the native host process crashes.

Environment

• Claude Code version: 2.1.37
• OS: Windows 11
• Bun version: Canary v1.3.9-canary.51 (d5628db2)
• Chrome extension: Installed, enabled, settings accessible
• Note: This previously worked and stopped working (likely after a Claude Code or Bun update)

Steps to Reproduce

1. Install Claude Code v2.1.37 on Windows 11
2. Install Claude in Chrome extension
3. Run claude --chrome-native-host or use /chrome in a session
4. Native host crashes immediately

Crash Output

[Claude Chrome Native Host] Initializing...
[Claude Chrome Native Host] Creating socket listener: \.\pipe\claude-mcp-browser-bridge-{user}
============================================================
Bun Canary v1.3.9-canary.51 (d5628db2) Windows x64 (baseline)
Windows v.win11_dt
CPU: sse42 avx avx2
Features: Bun.stdin(2) jsc standalone_executable 
Elapsed: 87ms | User: 125ms | Sys: 0ms
RSS: 0.31GB | Peak: 0.31GB | Commit: 0.47GB

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

Bun crash report: https://bun.report/1.3.9/e_2d5628dbEkgggC+s1oU+vvkOu8t/uBysi5uB__qt24tCA0eNrzzCtJLcpLzFFILC5OLSrJzM9TSEvMzCktSgUAiSkKPg

Configuration Verified

All config is correct:

• Registry: HKCU\Software\Google\Chrome\NativeMessagingHosts\com.anthropic.claude_code_browser_extension → manifest JSON ✓
• Manifest: points to chrome-native-host.bat ✓
• Bat file: calls claude.exe --chrome-native-host ✓
• claude.exe exists at expected path ✓
• Extension ID matches allowed_origins in manifest ✓

Expected Behavior

Native host should start and create the named pipe for the Chrome extension to connect.

Workaround

Puppeteer MCP tools work as a fallback for browser automation.