I don't know if the versions of Firefox we're using are similar--I'm on a Mac--but on mine, under the Bookmarks menu, there's an option to "bookmark all tabs." When you choose that, it creates a new folder (which you can name) in your bookmarks menu, and in that folder are the links for all the tabs you had open in that window. Later you can open a new window, go to your bookmarks, choose the folder--and at the bottom of the list of links should be the option "open all in tabs." If you choose that, it creates as many new tabs as you had originally and then opens the links in those tabs.

I don't know if this is what you had in mind, but maybe it will help. Good luck; web browsers can be a right pain in the tush. :-)