When you have the project settings window and build settings window open at the same time, the project settings window will remain under the build settings window even when it should be in focus.
This occurs on MacOS, but has no issue on Windows.

1. In any project, open the Build Settings (File -> Build Settings)
2. In the Build Settings window, click 'Player Settings'
3. Drag the Player Settings window that opens so it overlaps the Build Settings window.

Expected Outcome: The Player Settings window displays over the Build Settings window if they overlap.
Actual Outcome: The Player Settings window remains underneath the Build Settings window when they overlap.

This makes the window awkward to work with on a small screen.
Reproducible in 2019.3.0b1, 2019.2.2f1, appears to be an issue in any version that has the Player Settings as a separate window.

Also tested in 2019.2.0a4, player settings were in the inspector instead so it is not the same issue.

License type: Pro