I have used TN on Linux 18, 20 and 22 LTS. I upgraded to Linux 24.04.1 Since then I cannot access my old profile (with local mails and IMAP mails). I do not want to store the email profiles twice. 6 TB+ I uninstalled TB after the upgrade to 24.04.1, because I could not access the Windows Profile. I installed Betterbird then, because it was advertised as the 'cleaner' Thunderbird bugwise. I can run Betterbird, because I set it up newly for my IMAP emails. Took some time -) to get mail from the IMAP server. Therefore I waste local mail space under Ubuntu and under Windows. Nevertheless: I cannot get to the one mail profile which is stored on Windows when running Ubuntu. As in the past, I used the the abolute path of the directory and set the 'is relative' switch to 0. I tried two ways: Update in the profile.ini and alternatively added the profile using the profile manager. The error message is: 'Your Betterbird profile cannot be loaded. It may be missing or inaccessible' The profile IS there, because it works under Windows. Under Ubuntu I mount the Windows partion of course.
Finally: All that happened on my Tower PC. After all the trouble I did NOT upgrade my Laptop Computer and left it on Ubuntu 22.04.05 LTS. I can run TB without problems and access the Windows partition on the Laptop.