amp-video-iframe无法播放来自多个来源的视频

Question

amp-video-iframe无法播放来自openplayer.com的视频

我尝试使用amp playground中的脚本，但是没有运气

<script async custom-element="amp-video-iframe" src="https://cdn.ampproject.org/v0/amp-video-iframe-0.1.js"></script>
<style amp-boilerplate>
  body {
    -webkit-animation: -amp-start 8s steps(1, end) 0s 1 normal both;
    -moz-animation: -amp-start 8s steps(1, end) 0s 1 normal both;
    -ms-animation: -amp-start 8s steps(1, end) 0s 1 normal both;
    animation: -amp-start 8s steps(1, end) 0s 1 normal both
  }
  
  @-webkit-keyframes -amp-start {
    from {
      visibility: hidden
    }
    to {
      visibility: visible
    }
  }
  
  @-moz-keyframes -amp-start {
    from {
      visibility: hidden
    }
    to {
      visibility: visible
    }
  }
  
  @-ms-keyframes -amp-start {
    from {
      visibility: hidden
    }
    to {
      visibility: visible
    }
  }
  
  @-o-keyframes -amp-start {
    from {
      visibility: hidden
    }
    to {
      visibility: visible
    }
  }
  
  @keyframes -amp-start {
    from {
      visibility: hidden
    }
    to {
      visibility: visible
    }
  }
</style><noscript><style amp-boilerplate>body{-webkit-animation:none;-moz-animation:none;-ms-animation:none;animation:none}</style></noscript>
<script async src="https://cdn.ampproject.org/v0.js"></script>
<amp-video-iframe id="myVideo" src="https://openplayer.net/player/?key=cGRFNTFDTWRUazhEMGptMDJIN2oya3lpcUs1QjBlSEZqNDJiQXh2U3M1dz06SklmUVdTcER6TElFck1Sc3YrYWVJc2ZtYWtBQXc1ak1PNGpmWm1PcE84MD06U1dZdFJDWGpPYWFpNFp0eFNady9Fdz09Olc2WThnaEVZV1pjUVJKYVpaeGRFQXBVT1lqT3ZXRW1yN3FLUjk0eEVXbGpkRzZyY3Jsbm1vc0JKK2gwdHNSNTZUeXJGZ1AwS2ZLTi9LVHBqK3F4M0FBVHlKbHNma2s3SnRwemNpekhOaEtLRGF0WlVEdzFQMFlXOHN6Ym0zZmlmYjFYUXNQczFZMXdHMVd6eEtRUktMZ01PenFoUUlNdWV2OWJzeEVLdXZTaz0="
  width="720" height="405" layout="responsive" autoplay>
  <amp-img placeholder src="https://preview.amp.dev/static/samples/img/amp-video-iframe-sample-placeholder.jpg" layout="fill">
  </amp-img>
</amp-video-iframe>

如果我将src更改为https://preview.amp.dev/static/samples/files/amp-video-iframe-videojs.html，则放大器工作正常。 但是为什么？