Due to an crashe, I have to reinstall Dorico 3
Do I have to “arrange” my shortcuts again ? (I use stream deck)
No, key shortcuts are contained in user files, which are not deleted or overwritten when you reinstall.
Reinstalling is only a fix if Dorico wasn’t installed properly in the first place, or if some of its (non-user) files have been deleted or modified, which doesn’t normally happen.
A crash by itself shouldn’t require reinstallation.