Steps to reproduce:

1. Have the Scene editor be in opened of the editor, and undock it from the main editor window

2. Click on the Scene Camera settings icon (under View options) to show the sub-menu window

3. While the sub-menu window is displayed, close the Scene Editor window

Actual results: 

The Scene camera settings sub-menu window remains open, and goes blank when having the mouse hovering the window. It only goes away when attempting to click away from the window

Expected results: 

The Scene camera settings sub-menu window should be closed along with the main Scene Editor window

Reproducible with versions: 
2023.3.0b6

Not reproducible with versions: 

2021.3.34f1 / 2023.19f1

Can't test with versions: 

Tested on (OS): 

Notes:

• Similar to UUM-61904