Sorry for buggin’ development tag, but there’s no documentation about importing email and/or folders into email section
There’s some info about importing data into Webtop section
but maybe some experience/hints could ease some issues like this one
(reporting, for example that the subscribeall option of imapsync could ease some issues into webmail)…
There is not documentation because it’s not strictly related to NS, but more generally to an IMAP server.
But I agree that some documentation could be useful! Anyone willing to open a PR?
IMO, this is not a bug, I’d move this discussion under “Feature” section (@davidep).