Firefox upgrades fail to save Tabs and Bookmarks. Consequently, this is not a genuine upgrade but instead is the implementation of a new client. Previously, Firefox upgrades saved both Tabs and Bookmarks. Unfortunately recent upgrades no longer perform this function. Requiring users to manually (dangerously) search through past Profiles and hopefully select the correct profile to launch in an attempt to restore these two features is burdensome to users. Additionally, when one of many past profiles is selected for launch, Tabs are not restored. Previous Bookmarks are restore under different headings that require new navigation clicks to access. The first attempt to upgrade installed Firefox 72. After reverting back to the older version and attempting a second upgrade, the new launch was Firefox 100b. Go figure. As I write this message in a newly upgraded Version 72, I am uncertain as to whether or not to set this as the default version out of fear of not being able to eventually get my Tabs from my older version. So I will revert back to the older version in the hope that I might eventually learn how to defeat this current Firefox Fault. Thank you for the help and links to instructions to fix this problem that were sent. The steps provided were not clear enough to follow without repeatedly failing to fix the problem. IE: "Restore Session" options did not exist; Tabs were not restored when Bookmarks were restore in a completely modified user interface; the means to determine which of dozens of Profiles to select was not provided.