From: Nils dovecot@bugblatterbeast.de
Lots of the emails I send aren't stored in the sent folder. It seems that it mostly (but not always) work for sent emails where the main email-address (the one that is also used as login name) is used as sender. It never seems to work when an alias is used as sender name.
Sounds to me like some mail reader filtering rule.
Ordinarily, dovecot does not handle the capture of outgoing mail, Most of the time, it's the mail reader (MUA) that files outgoing messages to a sent-mail folder, and less commonly, the MTA will do it.
Mail readers probably employ their own logic to determine what belongs in the sent mail folder: it could be all outgoing mail, it could be redirected based on some role filter.
If you have a repeatable case, check it against your filter rule set. If it's inconsistent (the same message does and does not make it into your sent mail folder), you can look at other causes.
Joseph Tam jtam.home@gmail.com