I'm using IMAP and want to see subfolders of Mailboxes under them. The default folders are setup in Mailbox Behaviours to be under INBOX/Junk/Drafts/etc. The problem is new subfolders are moved under a separate section. Mail was restarted multiple times and I tried creating the subfolders on the server and in Mail and it's the same. This was working in the past but I haven't done it in Sierra before. Old mailbox: I created subfolders and they were added under the account's Inbox. New mailbox: Subfolders are added under a separate section. Any ideas on how to get the custom subfolders to be displayed under the mailbox Inbox?