This is quick guide howto switch desktop from GNOME 49/48/47 to KDE Plasma 6 and display manager GDM to SDDM. I use here GNOME and KDE as example, same method works from KDE to GNOME or GNOME to XFCE, etc. Check video guide, howto switch desktop from GNOME 49/48 to KDE Plasma 6 on Fedora 43/42: