Mac: "Quit MuseScore" doesn't work (sometimes)?
OS: macOS 10.14, Arch.: x86_64, MuseScore version (64-bit): 3.0.2.20666, revision: 8ca4d2c
"Quit MuseScore" on the "MuseScore" top-level menu seems to be nonfunctional.
Update: I did try it half a dozen times before reporting it. But now I tried it again, and it worked correctly. Make what you want of it.