How to get HTTP protocol version via JavaScript

Question

Is it possible to determine the version of the HTTP protocol using JavaScript? I need to determine if the user is using the HTTP / 2 protocol (and congratulate him if that is the case).

Answer 1

Only works in Chrome at the moment, but other browsers should be available soon.

console.log(performance.getEntries()[0].nextHopProtocol)

Answer 2

if (location.protocol == "http/2"){
    alert('congratulations!');
}