[BUG] Claude in Chrome (Cowork) operated unintended device's Chrome in multi-device environment via Parsec

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?

<img width="2044" height="1209" alt="Image" src="https://github.com/user-attachments/assets/5608df73-a541-47a1-b470-7f0f33f1db55" />

Environment

• Plan: Max 20x
• Platform: Windows (accessed via Parsec remote desktop from Mac)
• Claude in Chrome: installed on both Mac and Windows
• Chrome account: same Google account on both devices
• Claude account: same account on both devices

What happened

While operating Windows via Parsec (remote desktop) and using Cowork on Windows, I instructed Claude to create and edit a GitHub issue.

Expected: Claude in Chrome on Windows operates Windows's Chrome
Actual: Claude operated Mac's Chrome instead

Root Cause Hypothesis

Claude in Chrome appears to route commands to whichever Chrome extension instance responds first among all devices sharing the same Claude account. There is no mechanism to specify which device's Chrome should be controlled.

Why This Is a Security/Design Issue

Claude is designed as a multi-device platform (Web/iOS/Android/Mac/Windows). However, Claude in Chrome has no device selection mechanism. In multi-device environments, an unintended device can be silently operated without the user's awareness.

This is especially problematic in:

• Remote desktop environments (Parsec, RDP, etc.)
• Shared household/office devices with the same account
• Any scenario where multiple Chrome instances share the same Claude account

Steps to Reproduce

1. Install Claude in Chrome extension on both Mac and Windows
2. Log in with the same Claude/Google account on both
3. Access Windows via Parsec from Mac
4. Open Cowork on Windows and instruct Claude to perform a browser task
5. Observe: Mac's Chrome is operated instead of Windows's Chrome

What Should Happen?

Either:

• Claude in Chrome targets only the local device where the command originated
• A device selection UI is provided when multiple Chrome instances are connected

Users in multi-device environments should be able to predict and control which device will be operated. The current behavior undermines trust in agentic browser automation.

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce
*
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Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.91 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

_No response_