Very easy to use. Simplifies my Life!
Would be nice to have automatic backups as I close Firefox. Until now it´s only possible to have daily backups, which are generated when I´m starting Firefox. I don´t think that this is a smart solution, because these backups are not including the tabs I´m opening in the session.

Afer one of last updates regex for catching tabs stopped working correctly. I have some site inside my corporate network with address https://somesite/. I used "https://somesite/" filter to catch tabs with this site and it worked until some recent update. Now the only expression, that works, is "somesite", witch catches all sites with "somesite" in URL. Escaping "/" also doesn't work. It appears that any expression, that doesn't match examples in help tooltip, doesn't work (Firefox 70.0, addon version 4.2.2).
Update: Regex https?\://somesite/? works only when I open link to "somesite" in new tab inside browser. When I enter adress maually or open link from external app (i.e. Thunderbird), it doesn't work.

I can't explain how I've survived without this extension before.... This is perfect extension that is helping me on daily browsing, and daily tasks keeping everything organized and handy. It also saves a lot of space on the nav bar. This should be the default approach on Firefox, while it comes to browsing experience, but I am glad that this extension does the job perfectly. Well done Drive4ik and contributors, well done!

Unfortunately, some of the groups you create randomly lose all tabs. In the next session, only the empty groups will be there. Thus, the extension is unfortunately almost meaningless, too bad. Apart from this, the idea of the extension is great - if it would work though...

This addon has become a vital part of my firefox usage. I can even say it's one of the reasons I'm using firefox and also recommend firefox to others. I hate having so many tabs open. I prefer logical grouping of the tabs. It's more than a nice to have for me, it's a necessity. Great work.

Auto sorting tabs by keywords is ... I can’t decide if I need it, but it looks interesting.
Installed Firefox Nightly 71 + tab manager Tree Style Tab = while everything is stable.

Below was a complaint about the delay in opening the menu on 'F8' - yes, rarely, but sometimes the menu does not immediately open, or does not open at all.

The addon is nearly perfect and I love the group icons. It`s the best addon I´ve seen to manage tabs. But sadly it`s not working correctly anymore. When I change the group, some of the tabs change the group with me and stay active. Are you aware of this bug (probably from a Firefox update, since before it was running great)? I use Firefox Quantum.

Update: It seems like other Tab Group Addons are having the same problems.

FINNAALLLYYYYYYYYYYYY!!! FOR THE LOVE OF GOD FINALLY FUCKING FINALLY!!! I'VE BEEN LOOKING FOR AN EXTENSION LIKE THIS FOR OVER A FUCKING YEAR SINCE THE UPDATE THAT KILLED THE OLD GROUP TABS. FINALLY A PROPER EXTENSION THAT *HIDES TABAS* INSTEAD OF CLOSING THEM. THANKS MY FRIEND FOR MAKING THIS FUCKING PIECE OF SOFTWARE THIS MADE MY LIFE SO MUCH EASIER I LOVE YOU

This add-on is now completely broken. Tabs opened in or moved to a specific group will show up in all groups, obviating any benefit this add-on might create. Unless this is fixed, the add-on cannot be used anymore. It's probably time for Mozilla to develop a proper tab group replacement for modern FF.

Well until a few weeks ago.

The problem is the auto-backup, the backup no longer saves the tabs (this empty). Therefore, when the add-on is update and loads the last backup there are no more tabs.

I've had to disable auto-backup and restore my tabs manually with my last correct backup (2019-08-26).

Very useful. Thanks!

This is a sad joke:
- it doesn't work if 'Restore previous session' is disabled,
- it doesn't work in private mode.

As it is it's a waste of bits.

There is a bug that if I hit 'F8' or click icon to show up groups view all I get is a little modal. I need to click the icon again to show the groups. It's very annoying.

Screenshot - https://ibb.co/yYw1919

Simple Tab Groups is "exactly" what I was looking for to replace the old Tab Group Manager! I delayed upgrading from the old version of Firefox for a long time because I didn't want to lose the ability to group tabs. I tried several other tab managers first, but they didn't do what I wanted. STG is very intuitive, very functional, and easy to learn. I can't say enough good things about it! The only thing it lacks, compared to the old Tab Group Manager, is the ability to resize groups in the "Manage Groups" display, but this is a minor issue, and in some ways the ability to scroll down for additional groups is an improvement over Tab Group Manager, which couldn't scroll and would get very crowded with a lot of tabs and groups.

Been using this for a while and it's pretty nice. Recent update said to set the add-on to not work in incognito mode. Fair enough. I changed the setting. All my open tabs were lost immediately. My browser was reverted to the state it was in ~1 month ago. I can't even recover them with recently closed tab or recently closed window. For an extension that's supposed to enable my tab-hoarding, this is a low blow.