That whole dust up just ended up being some bugginess in their native EGL/Wayland backend, which was known, but it was amplified by some distros accidentally enabling the Wayland backend by default. A build setting triggered the default render path to use EGL, but if you just set GDK_BACKEND=x11 and force KiCad onto XWayland, everything works just fine. And those bugs have probably been sorted out in distros by now. See https://forum.kicad.info/t/not-the-selected-menu-under-wayla... for some details.

TL;DR their Wayland backend is incomplete, it accidentally got enabled for some users, run KiCad on XWayland instead until their EGL backend is ready.