Suggestion: E-mail filters: allow to check if a sender is in the users contacts address books
Suggestion to improve e-mail filters:
Allow to check if a sender is (or is not) in the users contacts address books.
This would allow to e.g. place all e-mails arriving from unknown senders in a separate folder, leaving in the Inbox only e-mails from known senders. Some people may want to handle unknown senders with higher priority because they may be new customers; for others, unknown senders may be mostly spam.
While for me this is an obvious first way to filter incoming e-mails, it curiously seems not to be implemented anywhere. Implementing this in OX App Suite or mailbox.org would give them a unique feature over other e-mail providers.