[BUG] Cowork shows infinite 'Thinking...' spinner after switching back from Code mode

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 switching from Cowork mode to Code mode and then back to Cowork mode, the UI gets stuck showing an infinite "Thinking..." loading animation (Anthropic logo spinner). The task results are never displayed regardless of how long you wait.

The only workaround is to completely quit Claude Desktop and reopen it — only then do the task results become visible.

What Should Happen?

Returning to Cowork mode should display the task results (or current progress) without getting stuck on the spinner.

Steps to Reproduce

1. Start a task in Cowork mode
2. While the task is running (or after it completes), switch to Code mode
3. Switch back to Cowork mode
4. Observe: the Anthropic logo spinner animates indefinitely with "Thinking..." text — task results never appear
5. Quit Claude Desktop completely and reopen — results are now visible

Claude Model

Opus 4.6

Is this a regression?

Not sure — this behavior has been consistent in my experience.

Claude Code Version

Latest (as of 2026-04-04)

Platform

Anthropic API (Pro subscription)

Operating System

macOS (Apple Silicon)

Additional Information

Screenshot of the stuck state (infinite spinner):

_Will attach screenshot in a follow-up comment._