This extension has matured a LOT! Extremely configurable. I've used Firefox with Tree style tab a lot in the past, then switched to edge for some time (once they added native side-tabs) and now floating between the 2 browsers. Been using visual tabs more recently to keep things simpler. Now trying Sidebery again & it's been a very nice UX, better then TST. Search tab feature is in v5 beta and that will probably round out what I need from this side tab type of extension :)

Extremely good work to update and maintain this actively for firefox which is right now an extremely good browser (even though missing side-tabs natively and we have to resort to custom overrides etc), thank you sir!

I have to use it longer but this may be even better than Tree-Style Tabs (which is very good, to be clear)

Replaces with benefits both Tree Style View and Simple Tab Groups. The first one still is great. The latter is very buggy. But Sidebery replaces both, with an smooth experience

This extension is the main reason why I give up on Chrome. Especial when Google closed a sync with Chromium.

The main reason I moved to Firefox. Like TST but consolidated with even more features. v5 is pure awesomeness.

By far the most customizable and efficient tab tree extension for sidebar style tabs. Combine this with some userChrome tweaks, and you have the perfect setup.

This is seriously the best extension of all time! This is more than just a tab manager or verticle tree tabs extension. It does offer that as a basic feature but offers SO much more. The new beta version you can find on the extension's Github makes the extension even better. Highly recommended for any power user!