My ISP offers a plan without IPv4 at a lower price. v4 websites only are served through their NAT64/DNS64 infrastructure and it works really well except for som

My ISP offers a plan without IPv4 at a lower price. v4 websites only are served through their NAT64/DNS64 infrastructure and it works really well except for some dumb applications that hardcode the IPv4 instead of using domain names (yeah, and also the ones that rewrite the entire stack in C and only support AF_INET...)