Phoronix: Mozilla Firefox On Wayland Is Progressing
Collabora remains interested in seeing Mozilla's Firefox web-browser with Gecko layout engine on Wayland...
I hope they will face the same issues like Audacious and port to Qt. I would prefer even Lynx over a GTK3-Firefox. Gnome team doesn't care about external projects, so I don't care about them!
Firefox already uses GTK and if you want Wayland support, it is easier to migrate to GTK 3 than rewrite that part but in any case, a Qt frontend work is also in progress. So you will have more choices going forward regardless of the toolkit you prefer.