I have seen reports of Firefox crashing under Wayland and that the way to make it work was to disable Wayland in Firefox or iirc to add a kernel parameter. Maybe it was fixed in Firefox too, but I saw some people saying the flatpak was somehow now affected (?)
I think it’s fine because the recording is not saved unless you explicitly tell it to save. If it’s anything like Nvidia’s shadow play, you set an amount of time, say 5 minutes that it keeps in memory, and when you save the clip, it simply saves that file containing the last 5 minutes.