I am getting strange behavior with Files/nautilus windows. If I open a document—I mostly notice this with LibreOffice documents—within a Files window by double clicking on it, and do some work, and then close that document using a keyboard shortcut the Files window also closes. This is annoying as I am constantly having to open new Files windows and re-navigate to some directory I am working in.
Is window focus somehow being shared between LibreOffice and Files? Why is this happening, and how can I make it stop?
I am using Ubuntu 18.10, Unity, and gdm3.
Edited to add details based on comments:
I have set "Close" in LibreOffice to ALT+W.
ALT+SPACEBAR C does not close my LibreOffice documents or my Files windows.
ALT+F4 does not "close window" but "quits program," so seems unrelated to the issue at hand.