I only know for KDE. It’s hidden away under System Settings–>Login Screen (SDDM)–>Behaviour.
On the contrary, By just having one 3rd party package (VLC) installed on a fresh system that showed the same issue it proved straight away that it wasn’t due to any conflict because of several other 3rd party packages I had already installed on my earlier effort.
Well the impression I’ve got in this thread suggests that no-one has had any issues with VLC on EOS, only me . So on that basis it would seem that it’s very unlikely anyone will have an issue like mine in future. All the suggestions, including the errors that I showed earlier were misleading, and virtually nothing shown on google was of any help either.
I got lucky with one post on the Videolan forum that showed a similar situation, because if I hadn’t stumbled upon it, my VLC issue would not have been resolved as it had nothing to do with conflicts, missing libraries etc, but a simple configuration within VLC itself, and it wasn’t ‘disable hardware acceleration’, which seems to be the stock answer by most on the web when VLC crashes.
Do you know if that command will be valid once KDE go full Wayland next year, ie will it override Wayland in favour of Xwayland as is currently the position?