I use Kubuntu 18.04 and I wonder what component implements the Alt+ Left Click drag.
Does the Display Manager SDDM implement this, or is it the X Server, or is it something within KDE? I'm sorry I don't know how all of this works together.
Background: I would like to see additional functionality e.g. when Alt+ Left Click drag moves a maximized window, but once it moves it to another monitor, it does not maximize it again. If I can know who i.e. SDDM, X or whatever is implementing this, I can investigate further what I need to do to fix this issue. This is just the background but not the actual question here.