Used to love this. I have autobackup set up after a round a long time ago of it losing all my tabs. I don't save every single backup for space. My oldest is currently from last June. I've been saving tabs for projects, work, etc and when I tried to save one today it simply wouldn't respond. The majority of my tabs are gone and the groups empty. I'm not sure when it happened; even my oldest backup only has a couple of additional tabs to add. A lot of the newer things I added aren't there. I've lost tons of stuff. With backups, it never occurred to me I needed to check to make sure things were still there to even be backed up; my bad, I guess, for not going through every folder making sure every single thing is still where it's supposed to be at least weekly. Everything is simply erased.

My tab groups' tabs suddenly placed on one tab group! 664 tab groups into one. 400+ tabs missing!

[3 September 2024 Update]: Great Addon but since I installed it, it conflicts with the 'Tab Session manager', and causes errors to my Firefox. Please fix that problem].

WOW! Thanks to this video on YouTube (How to Use Tab Groups in Firefox) BY "The Linux Cast
"channel. That has demonstrated this extension, and I am glad I found that video. Because this Add-on is Truly helpful and convenient to me. Because I have 3500 tabs open in my browser and it makes my life much easier now that I have them in groups! Thank you for creating such an awesome extension!! 🌟🌟🌟🌟🌟👍

No icon on toolbar and it is not cleat how to find it :(

kompletny bałagan, wszystkie zakładki w jednej grupie, pozostałe utworzone grupy puste zerowa intuicja tworzenia, a tak było kiedyś dobrze.

The best tab management plugin I've ever found. Easy to move tabs into different groups, and best of all, you can have many, many different groups without slowing the browser down because they are only loaded when necessary.

almost works for me but not quite :(

- no way i can see to include multiple windows in a group (for example, having multiple windows open for school and when i finish, unloading those tabs to open windows in a group for my art project. why does every window have to be a separate group?)
- difficult to add current tab/tabs/window to an existing group (a single and intuitive button for this is nice, like tab stash has)
- "other tabs" also not separated by windows, feels cluttered and confusing

As a recent Chrome uBlock Origin refugee, I was looking for something that'd replace chrome's tab groups.
This add-on does a little bit of that, but differently, and in several ways better.
First off, you WILL want to customize your browser toolbar to put the add-on icon to the top left of the app, right before the tabs. It's a much more natural place to use it.
Second, if you're using dark mode, the default icon is hard to see, and you'll have to tweak a config to fix that. It's spelled out in the "about this extension" page.
Third, if you multi-screen, this is MUCH better than chrome tab groups, since it allows you to trivially move tab groups between windows, and therefore screens.
I like that it can sync the tab groups into a bookmark folder.
The default group icons are awkward, but you can replace them with the favicon of any tab within the group, which solves that.
I just installed this a couple hours ago so I'm still wrapping my head around it, but I like it already.
I've got 12 tab groups already. Just don't expect it to be a drop-in replacement for Chrome tab groups. Take the time to wrap your head around the mental model of this add-on, it's worth it.

*Edit, now with more gripes!:
A dozen tabs or so (about 8% of my tabs) get detached from their group on every Firefox restart, which means on every Firefox update for me. I don't know why. It's not the same tabs each time. I tweaked all the settings I could, didn't help. I have to reassign the stray tabs in their proper groups after a restart, which takes entire seconds.
I'm kinda hoping this is going to stop happening on a future update. If I was a little less lazy, I'd probably try to debug it myself.

I was confused at first, didn't really understand how it worked.

The tabs are basically grouped by window, which is ok i guess but not what i was expecting.

You make a group, and if that group is active then any tab you open in firefox will be added to that group. any tab you close will be removed from the group.

If you activate a different group, your current tabs will be closed (and saved) and the new group tabs will be opened. In other words, you can't have two groups open at once.

It was unintuitive to figure out, but easy to use after figuring it out. However the functionality is not exactly what i want, the tab grouping in chrome is way better than this.

Essential plugin. Way better than Chrome tab groups. Does everything I need

I was looking forward to this solving my tag organization problem, but ran into two issues:

1. When creating a group, all of the open tabs were automatically added to it. I can't find an option to keep this from happening. It's certainly not the behavior I want -- I want to be able to create groups that I need, and leave all the other tabs alone, and this extension doesn't seem flexible to that extent.

2. Once all the tabs were automatically added to that group, I couldn't remove them without simultaneously deleting all of the tabs. WTF? I ended up having to walk back the entire installation, restore the session and clean up the resulting mess.

BRILLIANT! Simple, intuitive and classy. Open, create groups, drop and drag tabs between groups, then choose any one from the icon on top at any time.
I figured it out in 10 seconds, made 3 groups in 15 more, filled them in 20, and now just have to click their icon up top, and choose one of the three groups (which you can name, and which have a little color on each one).
This is a case of programming perfection: it could not have been made better!
Change colors and change icons or add your own in several common formats - download anything. Nifty!
I even grabbed a 1200x1200 pixel jpg off my PC and it worked, and shrunk it perfectly. Most websites choke on 128x128. Dude! :)