[BUG] Plan Mode Side Panel Won't Open

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?

Once Plan Mode gets corrupted and no longer honors comments in the plan panel, Claude also cannot be prompted to re-enter interactive plan mode, even in a new session referencing the plan file. Claude responds that it is in Plan mode and I should see the panel, but I do not.

What Should Happen?

The Plan panel should open and comments in it should enable a Revise button.

Error Messages/Logs

Steps to Reproduce

Plan mode left open in a tab for too long leads to it losing interactivity and then inability to open the panel in new sessions.

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

This problem spans versions.

Claude Code Version

Claude Code version: 2.1.185

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

OS (Darwin 25.6.0)