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mail_always_cache_fields = flags date.received size.virtual imap.bodystructure mime.parts hdr.importance hdr.x-priority hdr.references body.snippet
doveadm force-resyncfetch -u user@example.com body.snippet all > /dev/null may be used to force reindexing for already existing mails but please keep in mind that this might be a very expensive operation depending on mailbox sizes and other factors.
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