When requiring the entry of an IPv6 address, the regex pattern should still allow a dot, so that an IPv6 address can be entered in the format that has an IPv4-address-like part at the end: aa:bb:cc:dd:ee:ff:1.2.3.4 which is a valid way to choose to specify an IPv6 address.
IPv6 address can contain a dot
When requiring the entry of an IPv6 address, the regex pattern should still allow a dot, so that an IPv6 address can be entered in the format that has an IPv4-address-like part at the end:
aa:bb:cc:dd:ee:ff:1.2.3.4
which is a valid way to choose to specify an IPv6 address.