Comment # 19 on bug 1200547 from Hans-Rudi Denzler

I have a normal KDE installation.

With
splash=silent quiet plymouth.enable=0 
                    *****************
booting works like a charm. My Leap 15.3 with KDE has no issues at all.

If I would install "gdm" with YAST, I would have to install much to many
additional GNOME packages which I later would have to uninstall again.

> dir default-displaymanager
default-displaymanager -> /usr/lib/X11/displaymanagers/sddm

Sorry, I don't test this for you because the result would be:
no booting issues (my asumtption)