As with everything if you don’t know why it is probably money

Can home assistant be used without the ad-ons (I want to learn some smart home stuff, but do not want the overhead of a vm)

The rest of the comments are very good, but I’d recommend trying to administer a server and only connect to it via ssh. It will force you to learn cli as there will be no gui

Doesn’t that one have uac disabled?

That’s one of the problems with Firefox adoption at the moment. No normie will use a browser that might not work on a given site, but no developer will test for the 1% of users