desktopCapturer.getSources returns empty thumbnail in some window #44504
Description
Preflight Checklist
- I have read the Contributing Guidelines for this project.
- I agree to follow the Code of Conduct that this project adheres to.
- I have searched the issue tracker for a bug report that matches the one I want to file, without success.
Electron Version
33.0.2
What operating system(s) are you using?
macOS
Operating System Version
macOS
What arch are you using?
arm64 (including Apple Silicon)
Last Known Working Electron version
26.6.10
Expected Behavior
every window return its own thumbnail
Actual Behavior
some windows return its own thunbnail, others only return base64 prefix 'data:image/png;base64,'
Testcase Gist URL
https://gist.github.com/8eb6ea5620a0b2a271ff456f8933ac12
Additional Information
No response