JSFiddle - React, Tailwind, and code Playground

JavaScript

function downloadURL(url) {
var hiddenIFrameID = 'hiddenDownloader',
iframe = document.getElementById(hiddenIFrameID);
if (iframe === null) {
  iframe = document.createElement('iframe');
                iframe.id = hiddenIFrameID;
                iframe.style.display = 'none';
                document.body.appendChild(iframe);
            }
        iframe.src = url;
 };

downloadURL("http://www.nfl.com/liveupdate/scorestrip/ss.json");

var mapbody = window.frames['hiddenDownloader'].document.body.innerHTML;
//document.getElementById('hiddenDownloader').contentWindow.document.body.innerHTML;
//document.getElementById('hiddenDownloader').contentDocument.body.innerHTML;
if (mapbody){
var mapjson = JSON.parse(mapbody); 
}