I have some working preliminary Wayland integration for WebRender as of this week. However, there's a whole lot more than WebRender integration that needs to get done for Firefox to stand up on Wayland.
Thanks for the info. Obviously WebRender and Wayland integration are separate concerns but I was mostly curious if you had any idea if Wayland would address the issues you were running into with X11/Xorg.
Yes, Wayland is looking a lot better. The most important feature is transaction support, which is weird in Wayland but better than X, which has none at all.