The problem is that you cannot use "This Firewall" as redirection target IP, regardless of IPv4 or IPv6. "This Firewall" is not a SINGLE address.
Imagine you say "192.168.10.1, 192.168.20.1" there. What does that mean? Use ONE single IP there.
Imagine you say "192.168.10.1, 192.168.20.1" there. What does that mean? Use ONE single IP there.
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