Nick Howitt wrote:

Any chance of a further test update:We missed that IMAP and POP are defaulted off in a new installation. I've also moved the certificate initialisation to the install script from the update script.

Both changes should have no effect on an installation made before the update, but for new updates IMAP/POP should now be working (preffed on by "disabled_features =" rather than "#disabled_features = imap pop3" in /etc/kopano/server.cfg which defaulted it to off) or any new installation which installed 8.7.5 directly.