Claude-in-Chrome: not connected despite native host running (macOS, CC 2.1.76, ext 1.0.62)

Environment

• Claude Code: 2.1.76
• macOS: Darwin 25.3.0
• Chrome extension: 1.0.62
• Chrome profile: Profile 1 (not Default)
• Claude Desktop: also installed (1.1.6679)

Problem

tabs_context_mcp always returns "Browser extension is not connected" despite the native host process running and the Unix socket being accessible.

What we verified

• Native host config points to correct binary and is picked up by Chrome
• Extension installed in Profile 1 with nativeMessaging permission
• Native host process spawns and creates Unix socket at /tmp/claude-mcp-browser-bridge-steven/<pid>.sock
• Socket accepts connections (verified with Python socket.connect())
• Tried both Desktop and Claude Code native host binaries — same result
• Quitting Claude Desktop did NOT fix the issue
• Reinstalled extension — same result
• Ran /chrome command — same result
• Restarted Chrome and CLI multiple times

Chrome console errors

• Extension side panel shows CSP violation: script-src 'self' blocks inline script
• A listener indicated an asynchronous response by returning true, but the message channel closed before a response was received

Diagnosis

The native host spawns and the socket is created, but the MCP bridge inside the CLI never successfully handshakes with it. The CSP error on the extension's side panel HTML may indicate a corrupted or incompatible extension build.