I moved from using the GNOME graphical interface to KDE as I was having that common issue where the mouse will go off the screen to a secondary monitor when playing a game. Only reason I'm bringing this up is because this issue was not present on there but is here.
The issue I'm having is where some applications are laggy while others are not. For an example I could use FIreFox, Google Chrome or playing a game and its completely fine. But two applications which i use that are having this slowdown is Steam and Discord. If anyone knows if I'm doing something wrong or if there is a fix it would be much appreciated!