I'm having the same problem with both Ubuntu 18.04 and 20.04. Commenting the line
modifier_map Mod3 { Scroll_Lock };
does help but it does not solve it. My system does not freeze anymore but CPU usage still goes unusually up.
In addition, setting the brightness with the mouse by clicking and dragging on the top bar makes the brightness icon lag and causes the same odd CPU behavior.
I'm having the same problem with both Ubuntu 18.04 and 20.04. Commenting the line
modifier_map Mod3 { Scroll_Lock };
does help but it does not solve it. My system does not freeze anymore but CPU usage still goes unusually up.
In addition, setting the brightness with the mouse by clicking and dragging on the top bar makes the brightness icon lag and causes the same odd CPU behavior.
It also only happens on xorg.