I did it! I reinstalled the packages! All of 'em!
YAY! (Pun absolutely intended) I can now log in! Home sweet home! And also KDE has been updated to 6.0. But now I got a problem with SDDM, the theme isn’t loading and it complains about some private sessions module or whatever. But it’s okay, I will do something about it later. Thank you german computer doctor!
