Among the Firefox Wayland bugs, one of the top crash bugs is over a lost connection to a Wayland compositor. For dealing with it is to have a proxy between Firefox and the Wayland compositor to cache messages and prevent compositor message queue overflows.
Personally I didn’t have any problems with that yet fortunately.
My bigger problem right now is a bug that prevents me from copying stuff from the url bar when middle-click pasting is disabled in the KDE settings…
In X11 the bug doesn’t exist