I don't understand why you say this. Can you explain more?
> This would make the UX barely passable. If any of these domains change the content at all so the hash changes, how does it get updated?
Not a hash of the contents, just the sub/external domains' key-ids. Yes, the main page would have to change if you updated the keys. Doesn't seem too onerous to me.
>I don't understand why you say this. Can you explain more?
Not who you replied to, but with this system, I need to trust everything between the kiosk and the website server to not be MitMed. With the certificate system, I only need to trust the kiosk itself. Specifically, I need to trust the browser does TLS right, and I need to trust the installed root certificates are correct.
>> Not a hash of the contents, just the sub/external domains' key-ids. Yes, the main page would have to change if you updated the keys. Doesn't seem too onerous to me.
Then that means each external domain has to tell all its linkers that its key will change whenever it does. Assuming it even has such a list. What if a party doesn't respond? I understand it would be said parties problem, but it sure does make re-keying difficult.