You get it back by using supernova. Really it is that simple. I do not have the time or the patience to try and lead someone that needs assistance through that minefield of dataloss.

Now can we address the actual problems you had with supernova?

You get it back by using supernova. Really it is that simple.

No. it isn't simple.

In discussion here: https://forums.linuxmint.com/viewtopic.php?p=2381794 I learned that TBird can export profiles and then import profiles. But the export needs to be done before regression to a prior version of TBird. Why the TBird folks make this so difficult is beyond my comprehension.

I have the VMs (virtual machines) from today (with broken TBird 115), from a week ago (with 'working' TBird 115) and from 7 months ago (with TBird 102). I also have VHDs (virtual hard disks) containing the complete verbatum profiles from today, from a week ago, and from 7 months ago. I will boot the VM+VHD from a week ago, export that profile, then boot the VM+VHD from 7 months ago, blacklist TBird, update Linux to current, import the exported profile, and I'll be up-to-date but running TBird 102 with all my mail current.

Regarding what is wrong with Supernova, Wayne and i have discussed it but got nowhere. TBird is going in the wrong direction for me. I don't want a personal information manager that runs in telephones. I want a simple email client that runs in computers. I want what email clients were 25 years ago.

Simple: No accounts, multiple POP/IMAP servers as inputs, multiple SMTP servers as outputs. Correspondants are recognized by their @addesses. There's one @address folder per @address correspondant. @address folders are created automatically, as needed, based on "To:" & "From:" email headers. Sent and received messages are stored together (threaded) in their @address folders. That's it. Simple. No calander, no nonsense. Maildir of course. The directories ARE the @address folders. No SQL needed.

This is not a feedback forum. That is here https://connect.mozilla.org/

Bye now.