Often this points to a proxy somewhere that is in between and breaks it. I thought we had checks on environment variables, but that’s where I’d look.
I wouldn’t advise on disabling the registration because it provides some nice guarantees the proxy is actually in the correct state that you otherwise need to verify manually. It will also make upgrading harder, especially in the future where we’re going to rely on it more. There are also callbacks from the proxy that might break in the same way.