I recently upgraded my Thunderbird to the latest version (78) and in doing so, my personal address book is now empty. I have backups of the whole profile folder prior to the upgrade but there are no *.mab files anywhere in there. However there are a whole lot of *.sqlite files (abook.sqlite, abook-1.sqlite, abook-2.sqlite all the way up to abook-74.sqlite). I copied all these files into the current profile folder and opened Thunderbird but it didn't bring all those addresses in. I then tried the import option but it doesn't have an option for *.sqlite files. Can you please assist/advise how to import all my old address book contacts from the *.sqlite files into my current profile in Thunderbird v78.7.0?