Yeah - dovecot in F43 is hosed. You’ll be better off (the path I’m going down) not using the repo packages and all, setting up your config again and running it in something like docker - so your services don’t randomly break on upgrades.
Just upgrade to F43 today. What a royal PIA. I use dovecot on my server and use betterbird (enhanced thunderbird) on it and my chromebook. I use fetchmail to suck down mail from gmail and my ISP. I finally got dovecot so it will start. However, it does not see my mail folders nor my Inbox. Tried setting mail_driver in dovecot.con to both maildir and mbox. Restarted dovevot each time and restored my .thunderbird directory. When betterbird starts, it sees all the mail folders and my inbox but then the all disappear.
I may have just fixed it. Edited dovecot.conf. changed mail_driver and added mail_inbox_path
mail_home = /home/%{user}
mail_driver = mbox ← changed this from maildir
mail_path = ~/mail
mail_inbox_path = /var/mail/%{user} ← added this
found mail_inbox_path by reading through the output of doveconf -a and looking for any line with inbox in it. Found mail_inbox_path but it had a null value.
Lots of edits to files in /etc/dovecot/conf.d. Dovecot did not like the various plugin sections. I commented those out. Also commented out some metrics sections. Some sections were missing a name. Added “some_name” to those. Found out its just a name. Whatever you want to use. Also had to point it to my ssl cert and key files I get from LetsEncrypt. They changed the name of the variable. for example cert_file changed to ssl_server_cert_file. Same with key_file and dh_file.
Still seeing some errors on the journal log. Here is one example:
Error: Mailbox dovecot.index.log: open() failed with file /home/charlie/mail/.imap/dovecot
.index.log/dovecot.index.log: Not a directory