I use version xLights-2020.53-x86_64.AppImage on a Opensuse 15.2 system with glib 2.27-lp152.1.4 but the bug was already in the versions before. If I select a controller on the controller tab on the left side, the focus of the mouse pointer on the right side is some lines apart. Above it is correct, further down becomes the difference bigger.
In the screenshut I click on the last row (Sizes 2 480) the focus is on the row "Individual Sizes"
The same is below on the Layout Tab.
