Offlineimap not syncing mutt read/new/cur flags with dovecot mbox

[Number Six]

Hello,

I set up offlineimap with mutt to sync mail from a single account across
multiple computers and I have noticed that the read/unread status of my
mail does not seem to sync. Reading mail in mutt moves the message from
'new' to 'cur' in my offlineimap Maildir, and the N flag stays off
locally, but this state is not transmitted to the other computers when
they sync, even when I exit mutt or force it to write to disk.

My setup is standard, except for one detail: The mail server in question
is dovecot, and the mail folders are actually mbox on the dovecot side.
I am not doing any 'quick' syncs (offlineimap -q).

Is this a dovecot+mbox issue, or is there some other reason the 'cur'
status is not being synced?

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