Currently KMail supports finding duplicate emails in one folder, which is a nice feature. It would be great if this could be extended to multiple folders. Implementation idea: Track emails based on their message-id (as e.g. needed for bug #195009) and allow KMail to use that information to give the user a list: * Message 1 Folders: A, B * Message 2 Folders: B, C, D [...] Reproducible: Always
it's kmail feature not imap