How to set default session type to Plasma for sddm

[Kevin Kofler]

Dan Mossor wrote:
> That *should* be a setting in /etc/sddm.conf but I don't actually see it
> in the man page. Hmmm.....

Unfortunately, this is STILL not supported in upstream SDDM:
https://github.com/sddm/sddm/issues/326
https://github.com/sddm/sddm/issues/346

        Kevin Kofler