CG-NAT does not handle IPv6, which is the problem at hand if it can be fixed by using IPv4 only or by instructing the browser to disregard IPv6 in the first place.
Movistar in Spain is known to have issues with IPv6, there are lots of reports on this (also from this year, BTW).
Movistar in Spain is known to have issues with IPv6, there are lots of reports on this (also from this year, BTW).
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