The official documentation still issues a warning with respect to Maildir:
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Maildir would be better also for incremental backups.
Indeed. There seems to be only advantages for the use of Maildir, but noone in its right mind would do it with such a warning.
I would happy if MailDir (eml) could be finished so that it can be used safely.I'm switching from Apple Mail to TB at the moment and with the issues of TB 102.0 with mbox I was really worried about all my archived local emails. Separated files would help to keep 'worst case disaster' in limits.
I fully agree. I've been using it with no problems so far, but it would be nice to make sure it's fully developed.
I would just like to point out it is a maildir like implementation. It has never been intended to be maildir.
Other than that, I agree. it is a much-needed enhancement to the core functionality. Getting away from monolithic files that clog up backups, make the system unresponsive while antivirus scans etc fiddle with huge files that change often. Completion is long overdue.