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:
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/
Thanks for the tip! I’ll give it a look and see if that fits my flow any better!
Naaaah it won’t save you from your scattered X tabs… I’m in the exact same situation and it’s mostly an organization problem or focus on a single task !
I somehow managed to get a bit better by simply to force myself to clean my whole browser before I shut down my PC.
The implementation of vertical tabs pales in compared to Sideberry. Nice that it is heading in that direction, though. Plus, there is still Sideberry.