I am using Sabayon KDE 5.4
this is a fairly fresh install, but the following happened with past installs of same system.
my GUI crashes under the following conditions:
when an application is minimized to the task bar (bottom of screen), and I try to open the window by clicking that area, the display will crash and bring me straight to the graphical login.
this does not happen every time, and I have noticed it happens more frequently with my GTK applications (Thunderbird, Transmission).
I do not know if this is a problem with Xorg or KDE. nor do I know where to look for the proper logs yet (fairly new here).
I can post whatever information would be helpful.