Holy shit, I'm exploring the various sqlite databases that firefox saves and there is way too much data in there.
id; host; frequency; typed; prefix 360; play.google.com; -1; 0; NULL

what the fuck is that

If like me you're quite meh at using SQL for just exploring, I would recommend using SQLiteBrowser.
Meanwhile badwolf: Saving shit to the disk by default, why?
But well it really makes me think about what I should store and how.
For example firefox went for basically (with ignoring few things):
id ; host or url ; title ; frequency or visits ; typed ; lastVisited ; firstVisited

Which makes it really easy to get your top most-visited websites, which can be useful for suggestions or a homepage but dangerous if it ever leaks out a bit. (pic attached where you can see that I heavily used twitter and fedi, this db is few years old)

While I would naively go for something which is probably less-database-like and more log-file like:
id ; visit day ; url ; title

Which means that you would loose suggestion ranking/sorting based on visits frequency but then it could be done by the date, since even if you went a lot on say myspace for ten years, it's basically dead now.
Also if you wonder why I worry about data leaks: Some proprietary programs like games have been caught on abusing them without consent (IIRC the excuse was yet-again anti-cheat).

I would recommend people to use different users on their machine and chroots/jail/containers and stuff like AppArmor but there will still be folks not using this kind of protection because it has quite a bunch of drawbacks.

@lanodan

Are you surprised at this point, that a single webbrowser spawned a single foundation...