I can fix the small gaps in UID assignment with a change to Thunderbird. It seems that Zimbra does not like email headers sent via imap APPEND that begin with "From ". It causes Zimbra to sometimes ignore the "Date:" header and and also skip UIDs so they are not consecutively assigned. The proposed tb fix can be found here: bug 1741748
I still tend to think that a leading "From " in the imap APPEND messages should just be ignored by Zimbra. I've not noticed this problem with other servers.
I still tend to think that a leading "From " in the imap APPEND messages should just be ignored by Zimbra. I've not noticed this problem with other servers.
Statistics: Posted by gds — Thu Nov 18, 2021 12:14 am