Replication issue 2.3.7

[Stuart Henderson]

On 2019-07-13, Reio Remma via dovecot <dovecot at dovecot.org> wrote:
> Hello!
>
> I noticed these in the logs since upgrading from 2.3.6. to 2.3.7:
>
> Jul 13 11:52:10 turin dovecot: doveadm: Error: 
> dsync-remote(reio at mrstuudio.ee)</1ekE7qbKV2gYwAAsNnMGQ>: Error: 
> Exporting mailbox INBOX failed: Mailbox attribute 
> vendor/vendor.dovecot/pvt/server/sieve/files/MR lookup failed: Mailbox 
> attributes not enabled
> Jul 13 11:52:11 turin dovecot: doveadm: Error: 
> dsync-remote(reio at mrstuudio.ee)<MVs/K7ubKV2oYwAAsNnMGQ>: Error: 
> Exporting mailbox INBOX failed: Mailbox attribute 
> vendor/vendor.dovecot/pvt/server/sieve/files/MR lookup failed: Mailbox 
> attributes not enabled

Same here (in my case: on OpenBSD -current, mdbox, pigeonhole 0.5.7).
I have backed out to 2.3.6 + pigeonhole 0.5.6 and it's happy again.