title: Facebook Share Dialog "media" parameter?
body: <p>I'm trying to implement a simple Facebook Share Dialog with Facebooks own JavaScriptSDK.
  So far I built a little WebApp with a working share Button that calls:</p>
  <pre><code>FB.ui({
    method: 'share',
    href: 'https://developers.facebook.com/docs/',
  }, function(response){});
  </code></pre>
  <p>As I was trying different hrefs at one point, I sent an empty href resulting in this message:
  <a href="https://i.stack.imgur.com/VCMOx.png" rel="nofollow noreferrer">Error Message</a></p>
  <p>But I can't seem to find anything about this &quot;media&quot; parameter in the documentation of facebooks share dialog. Is this a &quot;legacy&quot; parameter? Or could it be used to load image data into the preview of the share dialog?</p>