Wayland imposes new rules, and one of those rules being that programs can’t arbitrarily access keystrokes and mouse input. This is done to protect against keyloggers as they are used by malicious actors to gain a bevy of information like passwords, banking information, personal information, etc.
I’m unsure if it’s Firefox, the RMM or both, but the necessary permissions aren’t granted and that’s why it’s not working.
It depends on your card & if you’re using Nouveau or the proprietary driver. NVIDIA has always been far behind in terms of Wayland compatibility when compared to AMD or Intel. Recently they seem to be putting in a lot more effort and now after Fedora officially announced that they will be dropping X11 by default in the KDE Plasma 6 Fedora Spin 18 months from now, they’re likely going to be trying much harder as Fedora sets the precedent. Even if it works on your hardware rn, that doesn’t mean it’s yet feature complete or bug-less.