[BUG] Clicking a Windows notification closes an unrelated parallel session

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?

When running multiple parallel sessions in the Claude desktop app on Windows,
clicking the action button on a Windows notification (the toast that appears
about a running session) closes one of my other open sessions instead of
focusing the session the notification was about.

What Should Happen?

Clicking the notification should focus/bring forward the session it refers to,
without closing any session.

Steps to Reproduce

1. Open 4 sessions in parallel in the Claude app on Windows.
2. Wait for a Windows notification about one of the running sessions.
3. Click the button on that notification.
4. Observe that one of the open sessions closes unexpectedly.

Claude Model

Opus

Is this a regression?

No, this never worked

Claude Code Version

Claude 1.11847.5 (9692f0) 2026-06-09T17:34:27.000Z

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

Actual behavior:
An open session is closed.

Environment:

• OS: Windows 11
• App: Claude desktop app
• Number of parallel sessions: 4
• Frequency: intermittent ("sometimes")