title: youtube: link to display HD video by default
body: <p>Is there a way to link a youtube video so that it plays automatically in HD?</p>
  
  <p>I've tried several things (adding &amp;hd=1, &amp;vq=hd720) but none of them works</p>
  
  <p>For example: 
  <a href="https://www.youtube.com/v/BH_lZSTYFHs&amp;hd=1" rel="noreferrer">https://www.youtube.com/v/BH_lZSTYFHs&amp;hd=1</a></p>
  
  <p>It starts always as 480p, it does not care apparently about the hd=1 parameter in the url</p>