Comment 8 for bug 1838473

The report asserts that allowing Ethertypes other than IPv4, IPv6 and ARP by default when iptables_hybrid is used is a security risk. It's not immediately clear to me that https://review.opendev.org/673692 blocks them. It looks like the hope was that https://review.opendev.org/670203 would do so, but it hasn't been finished for several years.