Tip of the Day: Child-folder-only IMAP folders
Maybe this is actually documented somewhere, but I had trouble finding it even though I have fun reading through RFCs. So maybe this is actually Dovecot-specific, but it wouldn’t shock me if other IMAP servers behaved the same way.
The problem statement: I wanted to have a folder under my inbox, with subfolders under it, but the parent folder not able to accidentally have mail items in it. So, a structure like: