Tree Style Tab could be incredibly helpful, except for some bugs. I'm running Firefox on a Mac running High Sierra. The main problem is my tab trees change on their own. It seems to happen randomly, at least I haven't detected any pattern, except sometimes trees change between exiting Firefox & starting it up again.

What's very weird: I've disabled the add-on since it was becoming useless as it kept changing my trees; so I'm working without trees. This mostly works ok. However, the tabs get rearranged when exiting & restarting Firefox! I have no reason to blame this on TST, except I never had the problem before using TST!

There's also one nuisance, which might not have anything to do with TST. Often when I duplicate a tab (& I think in some other situations) the tabs are scrolled so the new tab is at the left or right edge of displayed tabs. I find this to be very annoying since I lose the context of the tab, until I manually scroll the tab list.

Dave