I've found in using Acrobat Reader DC with an account for Mac OS X that when you open the application and are prompted for a password, you cannot click the Quit option (among others) in the application menu in the toolbar nor can you click the red X button in the upper left of the main application. You can't even close out Reader by right clicking in the dock and selecting Quit, something about the authentication form completely blocks other interaction with the application. Neither can you click the X in the authentication form. It is active, which is very misleading as it does nothing.

I've found that if I open Reader and haven't authenticated in a while, my only options to get the window out of the way are to authenticate or to completely reboot my computer. I could possibly use the Terminal to force-kill the application, but I really don't feel like authentication should be this hard of a block on being able to manage the processes running on my local computer.

My environment is as follows:

OS: Mac OS X Big Sur 11.0.1
Arch: Intel (x86_64)
Adobe Reader DC: 2020.013.20064

I was going to try and sign out and back in to get some screenshots of what I mean, but I couldn't actually find a way to trigger this "unauthenticated" state in which the application requires credentials to interact period. It just seems to happen at random that I'm unauthenticated again and have to navigate this issue to get use of my Desktop again.