All emails from the -shop (and the english Yiffy.Toys shop of cause)
should now be cryptographically DKIM signed.
This is, so that no spammers can use our domains for faked sender addresses.
We also have a DMARC policy, so all email still arrived but we get a report about how everything is working from the receiving email sercers.
Once this has shown no problems for a while, we will change the policy to first quarantine and later reject all unsigned emails with our shop as a (fake) sender address.