The beta d‘iOS 15.4 brings its (large) batch of new features, but inevitably the first users also begin to identify the most problematic bugs. Among these, there is a very annoying problem encountered by several Free Mobile subscribers. They notice that under iOS 15.4, their iPhone can no longer access certain sites. Blocking the site occurs when you want to connect to a site that does not yet accept IPv6 addresses (encoded in 128 bits).
Fortunately, there is a solution, but it turns out to be a bit radical and consists of deactivating IPv6 on its Free Mobile line (the address provided is then in IPv4), which opens up access to the sites concerned. According to a Free subscriber faced with this problem, the “bug” of iOS 15.4 would come from the management of IPv4 and IPv6 addresses, the Apple OS ensuring access to sites already managing two IP addresses (one IPv4 and therefore an IPv6).
Normally, Free is required to offer IPv6 for all sites passing through its network (it is a legal obligation) but the operator would be late and the activation of IPv6 would sometimes lead to a single IPv4 address. In short, it’s still a bit of a mess to know which of Apple or Free mobile should review its copy (perhaps both).