www.franconian.net/layouts/shortcodes/video.html

<figure>
  <video muted autoplay loop>
    <source src="{{ .Get "mp4" }}" type="video/mp4">
    <source src="{{ .Get "webm" }}" type="video/webm">
  </video>
  <figcaption>{{ .Get "alt" }}</figcaption>
</figure>