Doveadm error since 2.3.11.3 when run as unprivileged user

[Arjen de Korte]

I allow users to run 'doveadm' for mailbox maintenance (to expunge  
mail for instance). Since the upgrade to 2.3.11.3, this no longer  
works and results in the following error message:

doveconf: Fatal: Error in configuration file  
/etc/dovecot/conf.d/10-ssl.conf line 13: ssl_key: Can't open file  
/etc/ssl/private/de-korte.org.key: Permission denied

This is no surprise, as non-privileged users are not allowed to read  
the private keys of the server. Question is, why is doveadm trying to  
read this key in the first place (it is not needed for mailbox  
maintenance) and why is it failing now?

Regards, Arjen