Can't close child window in fullscreen mode

[alxmiron]

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 an issue that matches the one I want to file, without success.

Issue Details

• Electron Version:
  • v6.0.9
• Operating System:
  • macOS 10.14.6

Steps to reproduce

• Launch the app, set fullscreen mode for main window
• open child window from main window by new BrowserWindow({ parent: mainWindow }) ("Archive" page on screenshots)
• child window is opened in separate screen to the right
• move cursor to the top side of the screen

Expected Behavior

• Top toolbar with "close", "minimize", "exit fullscreen" buttons is opened
• User can close child window and move back to main window

Actual Behavior

• No toolbar is visible. User can't close child window
• Main window is black

Screenshots

https://streamable.com/slo6w

Additional Information

The but is not reproducible if child window was opened while main window is not in fullscreen mode

[ghost]

Is it on process? I am getting trouble with same issue.

[abettadapur]

This still is reproducible on 8.0.2

[AllSeeingEye]

Reproducible; child window doesn't have a title even in the "normal" mode.

[dertieran]

This is still an issue in electron@9.0.3 on macOS.

I noticed that this also happens when you fullscreen the child, even if the parent isn't fullscreen.
Because I wanted to prevent this, I found out that this doesn't happen at all if the child window isn't "fullscreenable".

So a workaround (or solution?) is to make the child window not "fullscreenable"

new BrowserWindow({ parent: mainWindow, fullscreenable: false });

(This is just needed on macOS as far as I can tell.)

[Maus3rSR]

Reproducible with electron v8.2.5 on duty!

[electron-triage]

The Electron version reported on this issue is no longer supported. See our supported versions documentation.

If this is still reproducible on a supported version, please open a new issue with any other new information that a maintainer should know.

Thank you for taking the time to report this issue and helping to make Electron better! Your help is appreciated.