clone() seems not to be working properly.

[Stradex]

This is mostly for any future user since I believe this is discontinued:

With fetch I use clone() to being able to call .json() or .text() more than once, typical example:

const res = await fetch(url, {method: 'POST', body: JSON.stringify(myBody), headers });
let fetchResData = null;
try {
  fetchResData = await res.clone().json();
} catch (e) {
  fetchResData = await res.text();
}

Doing that with regular fetch works, but you it does not work with this HTTP2 fetch. You will receive a "Body already used" error.