[BUG] VSCode extension: Conversation lost when moving panel to new window

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?

Moving the Claude Code panel to a new VSCode window caused the active conversation to disappear. The history dropdown doesn't show the lost conversation.

What Should Happen?

Moving the Claude Code panel to a new VSCode window should not change anything in the conversation. The history should retain all conversations - at least within one VS Code session.

Error Messages/Logs

Steps to Reproduce

1. Open claude in VS Code
2. Start a conversation
3. Move the conversation to a new window
4. The conversation will disappear and there will be only an 'Untitled' conversation in the history dropdown

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

claude-sonnet-4-5-20250929

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

_No response_