Me too. Seems to have a major update.
The conf system has been changed completely apart from other things I suppose.
The problem reported by a user cannot log in to roundcube and the following error:
Before the update: Warning: autocreate plugin is deprecated, use mailbox { auto } setting instead
After update: Error: Plugin 'autocreate' not found from directory /usr/lib64/dovecot
As the base system has been updated I think the solution is to fix the config files.
UPDATE: It is working now again. The solution was to Rebuild the mail services completely.
1. Check the log in /var/log/dovecot.log for errors. This is where I got the info above.
2. Tried to rename the dovecot.conf.rpmnew and use it as a main config file. Did not work as the conf.d folder files were not properly set. Ended up with going back to the original file.
3. Complete email service rebuild. After this I got the files updated as well and everything seems to be working.
Please let me know if you have any questions.