YouTube API and cross origin requests

YouTube does allow it. Make sure you are loading from a URL such as:

https://www.youtube.com/embed/HIbAz29L-FA?modestbranding=1&playsinline=0&showinfo=0&enablejsapi=1&origin=https%3A%2F%2Fintercoin.org&widgetid=1

Note the "origin" component, as well as "enablejsapi=1". The origin must match what your domain is, and then it will be whitelisted and work.

I think that error is actually misleading. I had the same issue, but I believe that it is actually chrome that is no longer autoplaying the hero. I get this error: Uncaught (in promise) DOMException: play() failed because the user didn't interact with the document first. https://developers.google.com/web/updates/2017/09/autoplay-policy-changes

The fix for me was calling mute on the video in Javascript Before playing the video. The iframe version of the embed with the same properties would not autoplay

<script>
      // 2. This code loads the IFrame Player API code asynchronously.
      var tag = document.createElement('script');

      tag.src = "https://www.youtube.com/iframe_api";
      var firstScriptTag = document.getElementsByTagName('script')[0];
      firstScriptTag.parentNode.insertBefore(tag, firstScriptTag);

      // 3. This function creates an <iframe> (and YouTube player)
      //    after the API code downloads.
      var player;
      function onYouTubeIframeAPIReady() {
        player = new YT.Player('ythero', {
          videoId: '3FjTef9gn3Q',
          height: '100%',
          width: '100%',
          playerVars: {
            rel: 0,
            controls: 0,
            showinfo: 0,
            autoplay: 1,
            loop: 1,
            playlist: '3FjTef9gn3Q',
            modestbranding: 1
          },
          events: {
            'onReady': onPlayerReady,
          }
        });
      }

      // 4. The API will call this function when the video player is ready.
      function onPlayerReady(event) {
        event.target.mute();
        event.target.playVideo();
      }
    </script>