[BUG] Claude Desktop Windows: periodic ~60s system-wide keyboard focus loss (~10s duration) while app is running in background

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?

Approximately every 60 seconds, while Claude Desktop is running, all keyboard input on the system becomes unresponsive for approximately 10 seconds. The cursor stops blinking in whatever application I am typing in. After ~10 seconds, focus automatically restores and I can resume typing normally. Clicking into the active text field immediately also restores typing without waiting for the timeout.
This does not appear to be a CPU or RAM issue — no spike is visible in Task Manager during the interruption. The behavior is consistent with the app causing a periodic system-wide keyboard focus disruption and then releasing it.

What Should Happen?

Expected Behavior
Claude Desktop running in the background should have no effect on keyboard focus or input in other applications.

Actual Behavior
Keyboard input in all other applications is interrupted for ~10 seconds approximately every 60 seconds. The cursor stops blinking during the interruption, suggesting a system-wide focus event, not just a local UI freeze.

Error Messages/Logs

Steps to Reproduce

1. Launch Claude Desktop
2. Switch to any other application (text editor, browser, email, etc.) and begin typing
3. Wait approximately 60 seconds
4. Observe: keyboard input stops, cursor stops blinking
5. Wait ~10 seconds — observe: input automatically resumes
6. Repeat — the pattern is consistent roughly every 60 seconds

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Any version prior to the April 14 UI rewrite

Claude Code Version

2.1.63

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

Isolation / Diagnostic Steps Already Taken

✅ Problem disappears when Claude Desktop is fully exited via system tray → Exit
✅ Problem persists when Claude window is minimized
✅ Problem persists when Claude window is closed but app remains in the system tray
✅ Problem persists after disabling the "Claude in Chrome" connector
✅ No CPU or RAM spike observed during interruption events
✅ No Cowork task is running during the interruptions