[BUG] CoWork: Chat switching causes user messages to anchor to bottom of viewport after conversation compaction

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 between chats in CoWork Desktop (macOS), user messages anchor to the bottom of the viewport instead of rendering inline with Claude's responses in chronological order. The conversation layout breaks: Claude's responses appear above, requiring upward scrolling, and the visual pairing between prompt and response is lost.
The bug does not occur immediately after launch. It appears to develop after the first context compaction event in a session, then becomes consistent — all subsequent chat switches exhibit the broken layout.

What Should Happen?

Switching between chats should load the full conversation thread top-to-bottom with scroll position anchored at the most recent exchange. User messages and Claude responses should remain visually paired in chronological order.

Error Messages/Logs

None visible. The failure is a UI layout/rendering regression with no error surfaced to the user.

Steps to Reproduce

1. Launch Claude Desktop on macOS
2. Open CoWork and begin working across multiple chats
3. Continue working until at least one chat undergoes context compaction (indicated by the compaction notice in the chat)
4. Switch between chats
5. Observe that user messages are anchored to the bottom of the viewport; Claude responses appear above

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude 1.569.0 (49894a) 2026-04-02T20:01:42.000Z

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_