[BUG] Cowork/Chrome MCP tab steals focus constantly — cannot multitask while Cowork runs

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?

Confirming this issue persists on the latest build.

Environment:

• Claude Desktop (Cowork): 1.1.9134 (87a63a) — 2026-03-26T22:41:57.000Z
• Claude in Chrome: 1.0.64 (Beta)
• Chrome: 146.0.7680.165 (Official Build, 64-bit)
• OS: Windows 11 (fully updated)

Behavior:
Starting March 26, whenever Cowork is executing a task that involves browser interaction, Chrome constantly steals focus back to the Cowork/MCP tab. I cannot switch to another tab or work in any other application — the focus snaps back to the Claude tab within seconds.

This was never an issue before the latest update. Previously, Cowork would work autonomously in the background while I continued working in other tabs or applications without any interruption. That was one of the best aspects of the workflow.

Impact:
This is a significant productivity blocker. As someone who relies on Cowork for client work while simultaneously doing other tasks, the constant focus stealing makes it impossible to multitask.

Current workaround:
Using a separate browser (Edge/Firefox) for regular work while dedicating Chrome exclusively to Cowork. This works but defeats the purpose of seamless background automation.

Request:
The active: false parameter proposed in this issue would fully resolve this. Chrome's native chrome.tabs.create({ active: false }) and chrome.tabs.update({ active: false }) APIs already support background operation — it just needs to be wired into the MCP tools.

Would love to see this prioritized. Thanks!

What Should Happen?

Cowork should perform browser automation in the background without stealing focus from other tabs or applications. The user should be able to freely switch tabs and work in parallel while Cowork executes tasks autonomously.

Error Messages/Logs

Steps to Reproduce

1. Open Claude Desktop (Cowork) on Windows 11
2. Give Cowork any task that involves browser interaction (e.g., navigate to a URL, read a page, fill a form)
3. While Cowork is executing, attempt to switch to a different Chrome tab or any other application
4. Observe: Chrome immediately snaps focus back to the Cowork/MCP tab within seconds
5. Repeat — focus cannot be maintained on any other tab or window while Cowork is active

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

1.1.9133 or earlier (worked before 2026-03-26)

Claude Code Version

1.1.9134 (87a63a) 2026-03-26T22:41:57.000Z

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_