Mac OS 10.15.2 applications do not quit
Shortly after installing 10.15.2, I've begun to have the problem of applications not quitting. Selecting "quit" causes the screens for the app to close, but it's still present in the "force-quit" list, sometimes (but I don't think all the time) its icon remains in the dock, and in all cases the app is thenceforth "dead," that is, I cannot use it again without a system restart. Force-quit sometimes appears to work (the app's icon disappears from the list), but in fact the app's still ghosting somewhere because I still can't use it. A normal system restart doesn't work, presumably because these ghost apps are interfering (sometimes I get the message that they cancelled restart, sometimes not), and so I have to hold down the start button for the requisite 10 seconds or so. This has happened with Firefox, Dreamweaver, and MS Excel, possibly others as well; it's a very frequent problem, but of course it doesn't always happen.
Anybody have a suggestion?
MacBook Pro 13", macOS 10.15
