Next and Back positions on tour dialogs inconsistent across computers
See https://github.com/musescore/MuseScore/pull/4054/commits/8ef7ec3aa64541… for more detail.
My computer displays the tour messages like this (don't mind the bad placement):
Obviously, the next and back should be switched. It might be good to give up on button roles and other similar things and just use layouts.
OS: Ubuntu 18.04.1 LTS, Arch.: x86_64, MuseScore version (64-bit): 3.0.0., revision: b6f663c