How do I restore my tabs and tab groups after an update to version 36.0?

Question

I work with many tabs when I use Firefox. I keep them ordered in Tab Groups, which helps separate the different kids of work I do and interests I have. I have been using this environment for years. When I started my work today, Firefox updated to v36.0, and the following behaviour was noticed:
1. There is only one tab group when attempting to show Tab Groups in Panorama, as opposed to around a dozen;
2. Normally though the hidden tabs (the tabs in the same group as the startup group and not the default page) don't download content until clicked, the name of the page and icon, if available, will show on the tab. Presently, the tabs show "New Tab" and no icon. There appears, however, to be the number of tabs that exist across all Tab Groups but now are ghosts this one, default Tab Group. I'd have to add, though, I don't count the number of tabs, so I can't be exactly sure. When clicked, there is just a blank page. So it is odd that Firefox knows they are there but cannot simply attach the address to it.
I have tried to restore the following files from my Windows Home Server backup to the AppData\Roaming\Mozilla\Firefox\Profiles\<gobbletygook>.default folder:
1. In the sessionstore-backups folder, I replaced the previous.js, recovery.bak and recovery.js files (not any of the upgrade~) with files from yesterday and from two days before.
When that didn't do anything, I replaced
2. sessionCheckpoints.json
I didn't see any file with a recent date that appeared to be one that I should restore. I should add that I do see hidden files. I thought about restoring the whole lot, but wasn't sure how this would affect the program on v36.0 and the profile files on 35.0.1.
I have deadlines this week and need to immediately restore my environment in order to make those deadlines. I have no list of addresses to my Web pages to work in IE or other. Any help would be very much appreciated.
On a second note, I had been wondering recently whether this tab group environment is a suitable way to maintain my work environment. Occasionally, when opening Panorama, I would get an error saying a script is taking too long, but if I clicked Continue, it would display the groups in a few seconds. I had considered putting all of it in Bookmarks though it would be tedious and more difficult to access and open multiple tabs. In the beginning, I tried Tab Groups thinking it was a simple matter of maintaining a table of addresses (in tabs) with a tab group ID or name. How could that go wrong? Well, it has, so it is obviously more complicated than that, and I didn't realise that upgrades would affect personal data. Should I abondon using tab groups?

Answer 1

With the help of information from user, ptressel, in [https://support.mozilla.org/en-US/questions/1032154#answer-673322 a post here about the existence of sessionstore.js when version 33 was released], I was able to easily recover my tabs and tab groups as follows:
# close Firefox and, perhaps, allow a few seconds (30s?) for any final closing of files;
# check to see if you have a sessionstore.js file in your profile folder, named like the one I documented in my original post above;
# if it is not timestamped prior to the discovery of your problem, open the sessionstore-backups folder;
# check if the recovery.js file is suitably timestamped and, if not, the recovery.bak.
# At this point, you are likely to find that none of them are prior to your problem occuring. If so, open your backups of this folder and go through steps 2-4 to find a file prior to your problem occuring.
# When you find a file, copy it to the root of your current profile folder and name it, "sessionstore.js"
# Open Firefox. Mine opened up as desired.
This is a Windows solution. Sorry I can't comment on other platforms, but I'd bet that as this is just a file copy and renaming, it is likely the same.
For Windows users, you may find you need to sign out and login as an administrator in order to access the backups. You need not logoff your standard account, but do have Firefox closed as described above.
Hope that helps.