IIRC main Fedora used to not do this until some update crashed people's sessions including the update process which left their install in an unbootable state.
The ostree based versions like Silverblue avoid this by their updates not touching the running system and instead creating a new folder structure with the updates applied that will be booted into on next boot.
I just use the Firefox flatpak from flathub.
Definitely a strange choice for a distro that pushes flatpak to not use it for the browser by default.
Are you referring to the ones with excessive sandbox permissions that flathub allows by default? Or is this something else?
Do you have a work profile or multiple user profiles set up on your device? This is similar to another issues they had a couple months ago, where my phone would fail to boot even into recovery to try to factory reset it.
This doesn't contain the game code either. It takes a user-supplied ROM and converts it to an executable. Nintendo do not own the code that performs the conversion.