[Bug]: Calling preventDefault on BrowserWindow close event still destroys BrowserViews' webContents

[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

What operating system are you using?

macOS

Operating System Version

Sonoma 14.4.1

What arch are you using?

arm64 (including Apple Silicon)

Last Known Working Electron version

29.3.2

Expected Behavior

Calling preventDefault on a BrowserWindow close event should not destroy the window's BrowserViews's webContents.

Actual Behavior

BrowserWindow close event destroys all BrowserViews' webContents, even when preventDefault is called.

In the attached jist, on versions of electron < v30, I'm able to close the app window and reopen the app by clicking on the Electron app in the dock. After version 30, reopening the app shows a completely blank window.

App after reopening on Electron <30

App after reopening on Electron 30

Testcase Gist URL

https://gist.github.com/yangannyx/0f758e003426f3829cb791aa3c51ac4d

Additional Information

No response

[codebytere]

Tracked initially to #35658 - your gist actually crashes after that first PR. That crash is then fixed in #41154, producing the current behavior.

Ah - looks like this change happens here: https://github.com/electron/electron/pull/35658/files#diff-8ad85e06abb8d70e94f4f58a38578024d942a6e039d8c18b27dd46f9cbb2fabdR57

@nornagon was this an intended breaking change?