claude-in-chrome: Browser extension never connects on Linux (tabs_context_mcp always returns 'not connected')

Summary

On Linux, mcp__claude-in-chrome__tabs_context_mcp (and all other claude-in-chrome tools) always return "Browser extension is not connected" even when all components appear to be working correctly.

Environment

• OS: Manjaro Linux, kernel 7.0.3-1-MANJARO
• Claude Code: v2.1.152
• Chrome: Google Chrome stable
• Extension: v1.0.74, installed fresh from claude.ai/chrome

Steps to reproduce

1. Install Claude Code on Linux
2. Open Google Chrome, install the Claude browser extension from claude.ai/chrome
3. Log into claude.ai in Chrome with the same account
4. Run Claude Code in a terminal
5. Try any mcp__claude-in-chrome__* tool (e.g. tabs_context_mcp)

Expected behavior

Tools connect to the browser extension and return tab context.

Actual behavior

All tools return:

Browser extension is not connected. Please ensure the Claude browser extension is installed and running (https://claude.ai/chrome), and that you are logged into claude.ai with the same account as Claude Code.

Investigation findings

All components appear healthy:

• Native host spawns correctly: ~/.local/share/claude/versions/2.1.152 --chrome-native-host
• Unix socket is created at /tmp/claude-mcp-browser-bridge-casper/<pid>.sock and is listening
• Socket accepts connections and responds (returns {"result":{"content":"Unknown method: ..."}})
• Cloud bridge wss://bridge.claudeusercontent.com is reachable (returns 426 Upgrade Required as expected)
• Native messaging host manifests exist in ~/.config/google-chrome/NativeMessagingHosts/
• Extension is enabled in Chrome, user is logged into claude.ai

Additional context

• Removing Claude Desktop (which was also installed) did not fix the issue
• Toggling the extension off/on, reinstalling fresh, and restarting Chrome all had no effect
• The connection fails both with Chrome stable and Chrome Beta
• Claude Code is being run in a terminal session (not via SSH from another machine)