Yes limited here.
It does indeed sound like a desktop environment relative issue. For all I know that’s a Wayland based issue if you’re using Wayland. A quick search looks like its only coded for X11 Wayland support - #3 by SkyeEden - Feedback for Unreal Engine team - Unreal Engine Forums so it would be using a compatibility layer in Wayland which could introduce issues like you experienced.
I used Gnome and X11 when I had tested UE4 on Linux and didn’t see any noticeable UI issues.
But the gpu driver is tied into that as well. There can be more pieces to that puzzle also. Its amazing how much stuff can affect the displaying of software UI.
But to add something relative to the topic. Wonder how full Wayland compatibility would change the compile times. A few seconds? Maybe minutes? It should change a little.