New profile after upgrade from ESR 115 to 128
I am working on upgrading our organization from ESR version 115 to 128. While testing, I am experiencing an issue where a new profile is being created and defaulted to on first run after the upgrade. This removes all the bookmarks, themes, extensions, etc. For a technical person like myself, I can easily revert this by going to about:profiles and setting my previous profile back as the default and then restarting Firefox. The issue lies in that this process is not something we can feasibly do for over 1000 people if/when they see this problem. I have been trying to wrap the install with a few commands to back up the previous profiles.ini and put it back after upgrade but this isn't working out too well.
Is there a way to automate keeping whatever profile was being used as the default intact without generating a new one and having it take over?
One thing to note is that we are following CIS guidelines as closely as possible, thus using synced profiles is not an option.