[BUG] App freezes after exiting fullscreen mode on macOS

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?

The Claude Desktop app on macOS becomes unresponsive (persistent freeze) immediately after exiting fullscreen mode. The freeze does not resolve on its own and requires force-quitting the app to recover.
Steps to reproduce:

Open Claude Desktop on macOS
Enter fullscreen mode (green button or Ctrl+⌘+F)
Use the app normally in fullscreen
Exit fullscreen mode (green button, Ctrl+⌘+F, or Esc)
App freezes and stops responding

Expected behavior:
App should return to windowed mode and remain fully responsive.
Actual behavior:
The window transitions out of fullscreen, but the UI freezes. Input (clicks, scrolling, typing) is ignored. The freeze persists until the app is force-quit via ⌘+Option+Esc.
Environment:

macOS version: [macOS 26.5 Tahoe]
Claude Desktop version: [Claude for Mac Version 1.8555.0 (8245b7)]
Mac model/chip: [MacBook Air M4 16 GB]
Display setup: [Single display (built-in MacBook screen, no external monitor)]

What Should Happen?

Expected behavior:
After exiting fullscreen mode, the app should smoothly transition back to windowed mode and remain fully responsive. All UI interactions (clicking, scrolling, typing, switching conversations) should continue to work without any delay or freeze. No force-quit should be necessary.

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce:

Launch the Claude Desktop app on macOS (built-in MacBook display, no external monitor connected)
Sign in and open any conversation (regular chat, no Cowork or Claude Code session required)
Enter fullscreen mode using one of the following methods:

Click the green traffic-light button in the top-left corner of the window, OR
Press Ctrl + ⌘ + F, OR
Hover over the green button and select "Enter Full Screen"

Use the app normally in fullscreen for a short period (e.g., send a message, scroll through a conversation)
Exit fullscreen mode using any of the following methods:

Click the green traffic-light button again, OR
Press Ctrl + ⌘ + F, OR
Press Esc

Observe that the app window transitions out of fullscreen, but the UI becomes completely unresponsive
Attempt to interact with the app (click anywhere, scroll, type) — no input is registered
The freeze persists indefinitely; the only way to recover is to force-quit the app via ⌘ + Option + Esc

Reproducibility: 100% — occurs every time fullscreen mode is exited.
Minimal context: No special files, code, or configuration required. Issue occurs with default app state and a standard chat session.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

I don't remember the previous version, but it worked.

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_