Firefox issue - can't get updates (non curated apps)

I’m having issues with Firefox:

1. It is a ‘non curated’ app, so when i try to select automatically update in the firefox setting, the toggle is greyed out and I’m told the app is managed by the system.

This seems very un-linux like. Surely there’s a method to override this non-curated stuff and allow users to take the risk and allow updates for any app? I’m going to be downloading a LOT of un-curated software.

2. The toggle to set as my preferred browser is also greyed out because of the same reason. I have tried setting it as default in the system settings, but still when I open links it opens epiphany instead.

Any advice?