zlacker

Honestly, I don't remember. A year ago when I was considering going back to vertical tabs, I read a bunch of discussion thread and articles, and got the impression Sideberry might be better. Tried it, and it resonates with me - unlike TST, which I tried and quickly abandoned several times over the year.

Can't really point to any concrete issue, other than I have a distinct feeling Sideberry is much faster/lighter, and feels more like part of Firefox vs. some bunch of JS faking an UI on top of it. Sorry I can't give you a more objective comparison. I did find this though:

https://old.reddit.com/r/firefox/comments/118ddge/tab_manage...

which is a recent(ish) discussion, and the points made there seem accurate.