shortcut keys cause the programme to crash
command + C, + X and + V shortcuts on 3.6 on Mac Big Sur cause the programme to crash, but the drop-down menus for cut, paste and command work OK. The command key does not cause a crash when it is used with up and down arrows to alter the octave while in composition mode
Comments
See #323160: Pressing the command key on your mac will bring down the program. and maybe see if you can figure out what your system and that one have in common. Must be some particular thing on both of your systems that isn't on other systems, since it works fine for most people (Mac included). Once someone figures out what the trigger actually is, we can investigate a fix.