[Bug]: BrowserView's content is visually wiped when vibrancy is set on Electron version 30 and up

[yangannyx]

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

30.0.0-alpha.1

What operating system are you using?

macOS

Operating System Version

macOS Sonoma 14.4.1 (23E224)

What arch are you using?

arm64 (including Apple Silicon)

Last Known Working Electron version

29.3.1

Expected Behavior

I expect the content of all BrowserViews attached to a BrowserWindow to render its content.

Actual Behavior

The content of one of the BrowserViews attached to my BrowserWindow is completely wiped visually (meaning background color and text content are not visible). However, opening dev tools on that BrowserView's webContents shows that the expected content is mounted in the DOM. Drag regions also seem to be respected.

I'm able to somewhat work around this by adding a dummy BrowserView before adding the BrowserView with content that got wiped. However, this isn't a stable workaround in other projects I work on to that have a more complex BrowserView<>BrowserWindow setup.

Long term, I'm looking to migrate off BrowserViews, since they've been deprecated in Electron v30+, but still want to document this regression.

Testcase Gist URL

https://gist.github.com/b6324fe3c894393da7a09676a927e9d9

Additional Information

No response