Sounds like a nothing burger. Firefox allows you to restore tabs. And you can turn off automatic updates. Seriously don’t understand where you are facing this issue. Every commercial grade software allows you to customise your workflow.
That's why I always update my browsers manually.
This definitely look like an issue with your own setup. But If you did face issues, you can always file a bug.
The point is that this is poor default user experience, and it should not be this way.