LOVE this extension!
Yup, it's simple, and it's great for keeping organized!

I have a group for "general", one for school, and one each for whatever games I might be into. (Right now Satisfactory and BattleBit.)
Super amazingly convenient to have these tab groups ready to go. They are much more flexible and easy to adjust than a bookmarks folder. Just right click a tab and send it to a group, or use the pop-up, or the manager.

You can even choose to hibernate tabs/groups (or not), but they'll still be "open" for later use. You can have a tab loaded and running some demanding applet, but still get it out of the tab bar so you can focus on something else momentarily. It's amazing.

Some of these functions are available in other extensions like Sidebery, but again I like this one for the Simple aspect. I use this in tandem with Tab Center Reborn for a (again, simple) vertical tabs sidebar, and now my toolkit of tab management is versatile yet lightweight, and still in dark mode!

I nearly forgot that sadly I'm here to comment on a pet peeve. The tab overflow icon, that little arrow managed by the about:config preference browser.tabs.tabmanager.enabled, is for some reason inescapable when using this extension, unless you are in the "other tabs" misc group which defeats the purpose.
Something to do with the behavior of the arrow: it is only supposed to appear if you have many tabs, but with this extension I can close all my tabs and just having the tab groups active even when empty shows the arrow. Small irk, very silly for me to be frustrated by, but there you go.
I don't know if I could possibly work around this using the extension's settings, I haven't tried, and I don't know if it could be patched by the extension dev to behave differently. So it's definitely still a 5 star extension. I love all the other stuff it has going for it.

Thanks Drive4ik for the great extension!!

BTW Mr. Dev, if you're reading, any chance for a feature like "automatically discard previous group when switching groups"? Or maybe a button that will switch to a group and discard other groups at the same time? My machine is not super strong and I run multiple apps at once, so it's usually best for me to hibernate inactive groups, and it's tedious to right click -> "discard other groups" all the time. Thanks!

Help people manage their cluttered Tabs in one dashboard. Great extensions!

This should be built in to Firefox.

Super

Great so far

Stellar extension. Chromium based browsers tab group functionnality pales in comparison. This has been single-handedly maintaining me on firefox for years.

This add-on is really great. It serves its functionally very well. I just wish there was a visible indicator for discarded tabs at all times. It's quite bothering having to open this add-on's menu every time I wanna remember if some tab was discarded. Otherwise, it's pretty great, and I'm thankful it exists! <3

This is pretty well an essential add-on. Who doesn't have a bunch of various tabs they need to open for specific activities. For example, to do your banking, to search for best hotels, to search for best pricing. This add-on lets you set up commonly used groups of tabs and does an excellent job keeping things straight forward and simple. THANK YOU for a great add-on.

*** The one thing I did notice is that when loading Simple Tab Groups for Firefox on a Mac is that the Simple Tab Groups gets buried and as a result, you can't find the STG icon. Search in your bookmarks, it's there. Then drag it to a visible part of your bookmarks bar. Next, right click and click Pin To Toolbar. There, the icon appears !

A few years ago Firefox had Simple Tabbed Groups (it was wonderful) and then Mozilla changed the Firefox code to be modern/more secure but it ended Add-ons like the old Tabbed Groups. That upset me I lost 4-5 tabbed groups with a total 81 links, just gone. Over the years I looked in the Add-ons for a replacement for Simple Tabbed Groups but nothing until recently. I looked at this Add-on and I said No, it can't be, but yes it is. I do not know if it is the same coder but thank you. I've got 3 groups and growing.

Actually an awesome extension ^^ Managing groups is a breeze, and I love that there are options to play with in case I need a little more granularity. Thanks to the dev for making this possible!

The best extension for managing multiple tabs out there!

It's good. Some suggestion: Please put the new created group on the top since we want to use the new group frequently.