I have about 760 tabs in my session. I worked for an hour and a half with this add-on to set up my groups, and when I reopened FireFox, it had erased all of my work. This add-on thrashed my tabs, then refused to show the management screen. I could see it blink on, then disappear. Sadly, this add-on doesn't work with large tab sets. Good thing I backed up.
[edit] Yes, session restore is enabled. Always has been. How else could you amass that many tabs?

best

Muito bom, resolveu os meus problemas de muitas abas abertas

Perfect !

Best extension ever. Clean af.

gppds

It's a must need, works perfect, good job!

It may by my particular experience by trying to import my groups from Panarama Tab Ghroups, but this extension consumed so much memory that turned Firefox unresponsive. The drag & drop functionality is sub par compared to other extensions.

Спасибо за хороший инструмент.
Почему-то в настройках группы не получается настроить захват регуляркой локальных документов по схеме URI file:///
Это вообще возможно?

The recent update causes an issue with new tabs - have to retype what I am trying to do twice in order for it to do what I want (do a goolge search, or go to the website)

That helps: (by rk)
EDIT. For those having similar issues. I think the trick is to open about:config and set closeWindowWithLastTab to false.

Simple and effective.