Checking "Use password manager to remember this password" makes password give error
For both send and receive message, I have to enter password again whenever I exit and restart Thunderbird (68.2.2 (64-bit)). If I check the "Use password manager..." checkbox, every send or receive fails, with an error message, for example: Sending of the message failed. An error occurred while sending mail: Could not get password for mail.mann.org. The message was not sent. How come I can't get Thunderbird to remember?
Opaite Mbohovái (1)
I would recommend you delete all password files and re-enter them when TB restarts and you connect to the account. Help/Troubleshooting, click Open Directory to open the profile folder, close TB. Delete or rename cert9.db, key4.db and logins.json.
If you still can't save passwords to the password manager when sending, check that there isn't another external password manager app on your system.