title: HTMLNode null when selecting nodes from htmldocument
body: <p>So I'm trying to get a soundcloud track ID, I'm not sure on how to go about this but so far I've figured out that I should be able to read a meta tag from the song's page on soundcloud. Here is my code: </p>
  
  <pre><code>string url = "https://soundcloud.com/hardstyle/scarphase-angernoizer-chaos-of-the-mayans-feat-tha-watcher-bkjn-vs-partyraiser-2017-anthem";
  HtmlWeb w = new HtmlWeb();
  HtmlDocument d = w.Load(url);
  
  var x = d.DocumentNode.SelectSingleNode("/html/head/meta[30]");
  Console.WriteLine(x.InnerText);
  </code></pre>
  
  <p>I'm trying to read the following tag: </p>
  
  <pre><code>&lt;meta property="twitter:app:url:googleplay" content="soundcloud://sounds:322162984"&gt;
  </code></pre>
  
  <p>So I can get the content and then get the track ID</p>
  
  <p>When trying to display the innertext of variable X there is nothing to display, when setting a breakpoint it says that X is null, can anyone explain me why this is and how to fix it?</p>