[BUG] [macOS 26.4 Beta 4] App Rapidly Flashes White/Gray on Launch (Epilepsy Risk)

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?

I'm running the macOS 26.4 Developer Beta 4, and there's a serious rendering issue opening Claude: sometimes the app will rapidly flash between white and gray; it could cause seizures.

Here's a screen recording.

What Should Happen?

...

Error Messages/Logs

Steps to Reproduce

Spam click the Claude application icon (triggers inconsistently).

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.66 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

Here's a screen recording.