Tabs and Menus Fried

Some of my tabs and menus are fried. Those that I remember from before the bug seem to work. I tried removing MuseScore from my computer, downloading a fresh copy, and re-installing, but that did not change anything. (I have not yet tried it on a different computer; that will be the next step unless somebody here has had the same problem and fixed it.)

A screen capture of the export dialog screen is attached. But the problem is widespread throughout the system.