See Use Tab Groups to organize a lot of tabs

I've read 'What are Tab Groups' several times. I've created several tab groups and named them. As long as the tabs are open I can switch between groups with no problem. However, when I close a tab it disappears from the assigned group. If I close FF and then restart it, all the tab groups are gone. Do tab groups only exist for the current session? That does not seem to be very useful. If that is the case is there a way to open groups of bookmarks?

Put all the bookmarks you want to open at one time in a single bookmark folder. Then click on that bookmark folder and 'Open All in Tabs'.

You can configure your homepage to launch several sites. Maybe do it that way. See How to set the home page

App tabs and Tab Groups (Panorama) are stored as part of the session data in the file sessionstore.js in the Firefox Profile Folder

• http://kb.mozillazine.org/Session_Restore

Make sure that you do not use Delete browsing, search and download history on Firefox to clear the "Browsing History" if Firefox is closed.

Firefox's session saving is unreliable IMHO.

Use Session Manager instead.

https://addons.mozilla.org/en-US/firefox/addon/session-manager/

You go to Tools/Options/General. On the first line, choose "Show my windows and tabs from last time. Next go to Tools/Options/Privacy and make certain Firefox is set to remember History. Finally, when you shut down, use File/Exit.

When I saw tab groups I thought Mozilla had created something to organize web sites so that they could be grouped, saved, and used at will from session to session. What a disappointment! I don't want to keep all those web sites open all the time. THE SOLUTION is the extension Speed Dial. It's perfect for most of the problems we have related to keeping tabs. Link: Speed Dial