The web uses port 443 for HTTPS, so this example is unlikely to be an issue. Having said that, there are weird and wonderful corporate and government proxy conf

The web uses port 443 for HTTPS, so this example is unlikely to be an issue. Having said that, there are weird and wonderful corporate and government proxy configurations out there that do wacky things. My guess is that their entire system is so tightly coupled that they can't unpick this without a huge amount of work that requires real developers to stick with it and get around it.