Claude in Chrome browser extension fails to connect despite all prerequisites being met

Environment

• OS: macOS 25.0.0 (Darwin)
• Shell: zsh
• Claude Code version: (CLI)
• Chrome: Google Chrome (latest)

Problem

The Claude browser extension for Chrome (claude.ai/chrome) is installed and all prerequisites are met, but the extension fails to connect when using Claude Code's browser automation tools (mcp__claude-in-chrome__*).

Every call to mcp__claude-in-chrome__tabs_context_mcp returns the following error:

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. If this is your first time connecting to Chrome, you may need to restart Chrome for the installation to take effect.

Steps to Reproduce

1. Install the Claude Chrome extension from https://claude.ai/chrome
2. Log in to claude.ai with the same account used for Claude Code
3. Restart Chrome after installation
4. Enable the extension in chrome://extensions/
5. Use Claude Code and call any mcp__claude-in-chrome__* tool

Expected Behavior

The extension connects successfully and tabs_context_mcp returns tab information.

Actual Behavior

Connection always fails with the error message above, even after verifying all 4 prerequisites.

Checklist

• [x] Extension is installed
• [x] Logged into claude.ai with the same account as Claude Code
• [x] Chrome has been restarted after installation
• [x] Extension is enabled in chrome://extensions/

Additional Troubleshooting Performed

• Confirmed com.anthropic.claude_code_browser_extension.json exists in NativeMessagingHosts
• Renamed com.anthropic.claude_browser_extension.json (Claude Desktop) to .bak to eliminate conflict
• Confirmed native host binary exists at ~/.claude/chrome/chrome-native-host with execute permissions
• Reinstalled Chrome extension
• Full Chrome restart (Cmd+Q) performed multiple times
• "Reconnect extension" causes Chrome tab to open briefly and close immediately
• Claude Code version: 2.1.92

Workaround

Using mcp__playwright__* tools as an alternative, combined with open -a "Google Chrome" <URL> shell command to open URLs in the actual Chrome browser.