[BUG] Pop-out/maximised plan window: text doesn't reflow to window width (related to #62543, closed not-planned)
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 using the expand/pop-out window feature for a plan in Claude Code on the macOS app, the text content doesn't expand to fill the width of the window — either when the window is popped out into its own window, or when maximised within the app. This leaves a large empty margin on the right-hand side regardless of window size.
This looks like the same underlying issue as #62543 ("Plan side panel: content stops expanding at a fixed width — large wasted empty margins on wider panel"), which was closed as not-planned. Re-raising here specifically for the pop-out/maximised-window case, since it's a plain, deterministic repro and the wasted space seems unintentional rather than a deliberate design choice — flagging in case it's worth reconsidering, especially alongside the still-open #57749 covering the related "narrow centered column" behaviour.
What Should Happen?
The plan text should reflow and expand to use the available window width.
Error Messages/Logs
Steps to Reproduce
- Open a plan in Claude Code (macOS app)
- Use the expand/pop-out feature to open the plan in its own window
- Maximise the window (or resize it wider)
Claude Model
None
Is this a regression?
I don't know
Last Working Version
_No response_
Claude Code Version
2.1.268 (Claude Code)
Platform
Anthropic API
Operating System
macOS
Terminal/Shell
Terminal.app (macOS)
Additional Information
Here's an obfuscated screenshot showing the issue
<img width="1432" height="1047" alt="Image" src="https://github.com/user-attachments/assets/cd3e2609-09d5-496f-a056-591ca6f6b3d6" />