Today we had the question Should IPv4 ICMP from untrusted interfaces be blocked?
While looking for references to provide a good answer I found a very similar question already asked and answered in the IT Security Stack Exchange: Is it a bad idea for a firewall to block ICMP?
What is the right way to proceed in this case? Shall we mark the new question as a duplicate? Is it even possible to do so when the new and the old question are in two different StackExchange sites? Maybe migrate the question? Or provide an answer with a reference to the old question?