I often have about 3 firefox windows open each with many tabs, and I get in the habbit of having the firefox windows always remain open. And if I go to shut down/restart my pc I'll synchronise via hamburger menu > my account, and it will automatically synchronise.
But it doesn't give me confidence that just automatically with a simple 'tick' I can safely shut down my pc and all my pages will be remembered. And I'm pretty sure I'd have synchronised and restarted, but the changes to the browser from 5 minutes before synchronising wouldn't have been saved.
So I would like if Firefox explained more-so that it did truly synchronise, and it would be cool to either make the synchronising more reliable or perhaps show me a tree list of the different windows and tabs that it's saved