Why is DKIM in relaxed mode?
mailbox.org signs outgoing messages with relaxed DKIM rules:
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=mailbox.org;
Just for information, why not use DKIM strict rules? If your MX are signing all outgoing emails, you should choose "strict mode" to make sure noone is spoofing our emails. Or do I miss something?