Latest Nightly exposed Tab Group in about:config
Go to about:config and type groups, it's being actively developed.
There's also another API that you can actually use if you're a developer in Browser Toolbox, enable Browser Toolbox
and type gBrowser.addTabGroup, you can add tabs to group using this API, and if you find a way to append it to Tab Tray you should be able to create something like this image:
As a user of the old Opera browser back in the day, I cannot express how much I have longed for this feature! Really looking forward to this 🥳
Yep, waiting for this feature so userChrome.js cook-ers can turn it into Tree Style Tab Group like Sidebery, with this config exposed it would be surprised if it takes long for us users to try the test version.
Smart Tab Group is pretty hype too.
This is a feature I want to love so much whenever I've used it in the past. It's great, it's useful, it's super awesome .... then, I just open 10,000 tabs [ok, that's an exaggeration, but I currently have 42 open and that's not even a lot] and they're scattered all over the place anyways and I can't seem to force myself to keep them grouped properly!
To anyone that can get their brain to actually utilize this feature, congrats that it's finally coming to Firefox!
I'm glad that it's coming natively, but hands down there's a whole lot of progress they have yet to make to come close to the usability provided by Sidebery, good that they're also working on native vertical tabs in fact! So I think that if you're looking for a better system you could try out that extension https://addons.mozilla.org/en-US/firefox/addon/sidebery/
Very excited for this. They were added to chrome around the time I stopped using it. The tab group extensions are all a bad fit for my needs. Excited for it natively.
Where did you find that image?