As long as you don't login to your ff account on any other devices it will essentially only be on on this one if you sync it. Sync isn't hosted on a server or anything, it just pulls from other devices when you sync it up

It won’t save ANYTHING. All it wants to do is sync. The info box shown in the help narrative never shows up on my Mac. Only the box trying to get me to sync

THANKS, Eve, for trying to help. I just deleted Firefox from my mac. If it won’t save passwords in 2020, it is worthless to me.

It only asks to sync in the sync menu, NOWHERE ELSE.

If you want to save the passwords locally just open the settings page, search for "password" and enable the option to store them (which is most likely disabled). Firefox has been able to store passwords for more than a decade. If you can't find such a simple thing in the settings menu, then you're just hopeless.

Normally the option to store passwords is enabled by default, which means someone might have disabled it in your pc unknowingly.