A nice addon to replace original Tab Groups.
But there are two majors problems :
1. At startup, Simple Tab Groups always reopen 2 or 3 tabs that where closed in previous session
2. It's no more possible to switch groups of tab after a few minutes of usage. There is an error "Invalid tab ID". Only possible way is to restart firefox or reload STG addon.
Note : I have near 300 tabs opened in 11 groups (75 in groups with most tabs), if this help

Update 13.02.2019
It look like version 3.3.7 fixed problems described above.
I have no more closed tabs auto re-opening and since update I don't have Invalid Tab ID error.
Or maybe it's Firefox 65 ? Anyway, 5 stars now !

It would be great if STG worked fine with the last Extended Support Release of Firefox (currently 60.3.0). This E.S.R. is used in corporate environments (like my government).

Unfortunately last STG available for this Firefox version crashes very often, mixes tabs between groups and ends up not showing the Group Administration Tab.

it just works.
it help managing multiple tabs and doing it pretty neat

Thanks for great addon.
I have question,
is there any way to change backup folder?

thanks for the fix ! it's good again

Your add-on is the main reason I decided to update my Firefox lately. But it would be perfect if the old "Move to group" feature in each tab's context menu is implemented, just like the good old days...

Quick little nitpick: opening a tab group tries to load every single tab simultaneously which for larger groups can lead to heaps of lag and ram usage. older tab groups only held onto the tab page and a thumbnail and loaded them when they were selected which was much better for me. Also the tab management page could be smoother. Lastly, I like how current pages can be retrieved when opening a tab group without saving to one before hand so I don't lose pages I didn't want to but I would like active windows to be saved to a new tab group automatically when switching to another group and not already a part of one but not with only "new tab" active.

First of all: A BIG THANK YOU! This is looking very good! FF after 56 was a big regression!
Tab groups should be part(optionally or not) of every FF, like tabs are. I mean if you have files, you have to have folders/directories!
In order to be 100% helpful, tabs, have to have 4 important things:
1. Free arrange and rename the tab groups;
2. Saving the session at will and automatically(every hour or so) before FF crashes or is closed normally;
3. Possibility to move tabs from one group to another.
4. A "tab group bar" above the tab bar, with a button to hide/show the "tab group bar".
I guess you have already covered most of this and I hope you will do your best for the others!
Cheers !

EDIT : take a look at this: https://postimg.cc/SJhgfGdn
for clarification about paragraph 4. See that green T to the right of the tab bar....that is the button with which left click show/hide the "tab group bar".

Panorama is back... and better! Hooray

Cool

Thanks so much for essentially reviving the Tab Groups/Panorama feature! Some other extensions have tried and not quite hit the mark, but this one is the best so far. Hope you're able to take it even further as the WebExtensions API expands!

效率低不说了，还丢组，上次重启Firefox之后就丢失了全部分组和标签。

Thank you for reincarnating such a vital feature. Last thing I miss( and miss SO much) is 'free arrange' - I mean to have the tabs on the whole screen, not in a small pre-arranged window. may I ask when it will be ready? I really cant stay on old Firefox no more(

I wish you implement "select last active tab after closing current tab" feature.

I have tried 2 other addons that bring this functionality, but they both conflict with your addon:

When I switch from group A to group B and then close active tab in this B group - I am switched back to A group. That works like it should be: last active tab was that one in A group.

But if I switch back to group B again - then any active tab from A "moves" to group B.

:(