Error: Cannot access a chrome-extension:// URL of different extension

[phillt]

Issue Description

I am encountering an error when using the Browser MCP server with the message: "Cannot access a chrome-extension:// URL of different extension". This error prevents navigation to any URL, including public websites like facebook.com and github.com.

Steps to Reproduce

1. Start the Browser MCP server as configured in ~/.bernard/mcp.json.
2. Attempt to navigate to any URL using the browser_navigate function (e.g., https://www.facebook.com or https://github.com/browsermcp/mcp/issues).
3. Receive the error message: "Error: Cannot access a chrome-extension:// URL of different extension".

Environment Details

• MCP Configuration: ~/.bernard/mcp.json contains "browsermcp": {"command": "npx", "args": ["@browsermcp/mcp@latest"]}.
• Platform: Running on a local machine with Bernard AI assistant (provider: xai, model: grok-3).
• Date of Occurrence: February 10, 2026.
• Browser: Likely Chrome (as the error mentions chrome-extension:// URLs).

Expected Behavior

Navigation to the specified URL should succeed without errors related to extension access.

Actual Behavior

Navigation fails with the error "Cannot access a chrome-extension:// URL of different extension".

Additional Context

This issue persists across multiple attempts and different URLs. It may be related to a conflict with the Browser MCP Chrome extension or browser security settings. I am unable to access the GitHub issues page directly due to this error, so I am creating this issue via the GitHub CLI.

Request

Could the team investigate this error and provide guidance on resolving or working around it? I am happy to provide additional logs or configuration details if needed.

Thank you!