Tabs gone after Firefox close.
It happened right after all groups just deleted itself and all 100+ tabs were on main view.
BUT
I just noticed that this extension is making backups every day by default. Due to this, I was able to restore all of the lost tabs.

So am changing rating from 1/5 to 5/5.

That's literally what I need from such extension. Keep up the good work!

Works as it says, but it keeps downloading files automatically into folders similarly named "STG-backups-FF-137.0.1".
Why does it do this? How do I make it stop?

Please continue working on it. This add-on is much more convenient than the Chrome-inspired, brand-new built-in tab groups feature.

Very good extension, but it have a very big bug:
When you delete an group, all tabs from all groups are remove.

very ugly user interface, barely usable

Add-on suddenly stopped working, which was quite a disappointment.

Legit kept hiding my taps and I couldn't make groups show on the tab list

Please add an option to change the backup location

Works absolutely as expected, extremely useful to me, very happy with that extension.
Only one complaint: I want better control over the folder where backups are created! Because my Downloads folder is clogged with tens of STG folders of different versions...

Keeps loosing my tabs when I close firefox.

Become one of my favorite extensions!

Its nothing Simple. The using give no effects. I'am nowhere see groups.

Simple and effective. Has a few integration shortcomings to my feeling, but nothing in the way of it being great.

First time using. Had two separate FF 136.0.4 (64-bit) instances open with multiple tabs on Win 10 Pro, up-to-date.

Created a new group, made a typo and deleted the empty group. The main instance containing the tabs (over 30) I wanted to group closed and isn't recoverable, two days of research down the drain.

And now I need to find an alternative.

Not clear how to use. needs better instructions

Garbage.

This one really ticked me off. I've only been using it for a few months, and yes. . . it was great while it lasted. Then after having created a number of very specific tab groups it suddenly went belly up. All the tab groups still exist, but every single one of them is empty with none of the saved pages within them.

To toss salt in an open wound, STG also stopped backing up the groups the day before it did this. Oh, and it had this nasty habit of randomly choosing whatever folder to dump the back ups in with no apparent means of changing that location to a folder of my choice.

In my case it was always my Downloads folder which quickly began to get messy with all these back up files. For the life of me, why the Downloads folder and not an Application Support or Preference folder is beyond me. But hey... what do I know?

Fine...

So, after the loss, all I could do was just restore the damn thing with next closest date and deal with the loss.

Yeah...

Well, the very next day it did exactly the same thing. This, after stupidly believing that it was a fluke, maybe having something to do with Mercury going retro again. Then proceeding to create some new groups that I needed to keep track of thinking that all would be well.

Once again... STG created no further backups and thus every single Tab Group contained nothing but that great big "0" for contents saved.

So, ya know what?

It's time to just stop trusting in these rinky dink add-ons for anything serious or important. Just trust in the basics. I've had too many situations like this happen where I've put time and effort into using add-ons only to have any number of problems. The big three I list below.

1.) Their creators cease supporting them and vanish from the face of the Earth, leaving people to scratch their asses as to wonder if there will ever be an update, fix, or just a simple sign of life from them ever again. A great example of this is the Apple Store. That hot mess is now chuck full of abandon-ware since Tim Cook raised rates for the store. That, and you will be very very very hard pressed to find an actual true free app instead of the ploy used to get you to download some adware laden, extremely limited version that will require a subscription. The good ol' days are long gone now. But considering the past ten years of Apple's arrogance and growing greed, who can blame the developers?

2.) Browser developers change something and suddenly an add-on you've relied upon for years is no longer supported. And no signs of life from their developers are to be found.

3.) Add-ons suddenly become defunct just for the sake of doing so. Developers have long since vanished, and unless someone, somewhere decides to risk taking on that add-on in some way (take Imagus for instance) people can only wish upon a star with their fingers up their holes, sitting and spinning in hopeful optimism like children promised a lolly if they behave at the dentist's office.

Nope. I'll keep using what I have. But, over the past twenty plus years, I've learned my lesson. Don't rely add-ons for serious long term usage. And forget any of them requiring subscriptions. I'm all for paying people for their products. But I'm not for becoming enslaved, ensnared, and transformed into a walking, talking, human, ATM for life paying a subscription for something that eventually will go the way of the DoDo Bird, like so many other add-ons, applications, and apps I've relied upon in the past.