Apple Mail: Mailboxes with different IMAP path prefixes For the Apple Mail client (this problem does not appear for Thunderbird Mail), I struggle with the following problem: I seem to have Mailboxes with different IMAP prefix paths. If the IMAP path prefix is empty, I see a bunch of Mailboxes (not under the label "Mailboxes", which has the default ones, like "Inbox", "Drafts", "Sent" and "Trash"). If I change this prefix to INBOX, I see a different set of Mailboxes (again, the standard Mailboxes ("Inbox", etc) are available here, too). I would like to have all Mailboxes show up at the same time (using a unified path prefix). Any help is greatly appreciated!
Yes, the IMAP prefix can be set in Mail Preferences > Accounts > mail@example.com > Server Settings > Choose Advanced IMAP settings. Type in your "IMAP Path prefix" e.g. INBOX



Note: In previous macOS versions (e.g. El Capitan, Yosemite) you will find "IMAP Path prefix" setting below the Mail Preferences > Accounts > mail@example.com >  Advanced tab instead.