Claude in Chrome extension lost connection to Claude Code after Chrome updated to v148

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 Claude in Chrome (Beta) extension stopped connecting to Claude Code after Chrome auto-updated to version 148.0.7778.168. It was working correctly a few days ago on the previous Chrome version.

Symptoms:

list_connected_browsers returns "Claude in Chrome is not connected"
All mcp__Claude_in_Chrome__* tools are unreachable
Extension is installed, enabled, and signed into the correct Anthropic account
Extension settings show "No sites have been approved yet" (site approval prompt never appears)
Restarting Claude Code, toggling the extension off/on, and reinstalling did not fix it
Environment:

What Should Happen?

list_connected_browsers should return the connected browser device, and Claude Code should be able to control Chrome via the extension.

Error Messages/Logs

Steps to Reproduce

1. Install Claude in Chrome (Beta) extension in Chrome
2. Sign into the extension with your Anthropic account
3. Open Claude Code desktop app (latest version) on Windows 11
4. In a Claude Code session, call list_connected_browsers via the Claude in Chrome MCP
5. Result: "Claude in Chrome is not connected" — browser never detected

Note: This worked correctly before Chrome auto-updated to v148.0.7778.168.
No code changes were made on our end. Restarting Claude Code, toggling the
extension off/on, and re-signing in did not restore the connection.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Chrome 148

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_