In this post I am going to explain how to enable GUI root access on Debian 9 – KDE5 Plasma (thanks to Dario Alejandro for the instructions). The following instructions vary those published in previous posts, as those explain how to enable Gui Root Login in Debian 8 and Debian 9 for gnome.
At this point I should once again warn you that using root access can ruin your whole system. Don’t use it if you don’t know what you are doing!
One can get GUI root login on KDE5 Plasma running sddm as follows:
1) set the root password “sudo passwd root”
2) in /etc/sddm.conf change MinimumUid=1000 to MinimumUid=0
3) in /etc/pam.d/sddm comment out “auth required pam_success_if.so user != root quiet_success”
4) Reboot into the glory of root access! Don’t bjork your machine now!
I hope this helps!