Black screen with mouse cursor on bootup - KDE
https://forum.kde.org/viewtopic.php?t=15152031.12.2019 · Re: Black screen with mouse cursor on bootup. Sun Mar 18, 2018 5:44 pm. Probably you didn't let discover finish installing updates so you have now broken packeges/system. When you get to the black screen hit ctrl+alt+f1 and log in into terminal with your username and password. If would be good if you can connect your pc to internet with lan cable.