Thinking of buying a refurb Mac made in Jan 2023. They don't say what OSX is installed. If I use Migration Assistant to copy the whole hard drive from my 2011 machine running El Capitan and Thunderbird 60.90.1, I may find that this old version of TB will not function. So I would try to install a newer rev of TB, but not all the way to rev 115. If I'm lucky, it will not be a "new install" because then I would have to previously find & save the Profile.ini and that other .ini file. I don't remember if I also need to save the actual email data separately, but of course I want that as well. And then I would have to do a complicated process to copy the Users and emails back into the newly installed version. I did this once long ago & don't relish figuring it out again. However, the process of Migrating and fixing all the Preferences etc on the new computer might take me some days, and in the meantime I would be sending & receiving emails on the old computer. So I would want to take THAT data and stick it in the new machine. So can anyone tell me if my old rev of TB is likely to function?