title: Sp.Ui.Dialog.js error - Unable to get property 'STS' undefined or null reference
body: <p>My problem is that when I start my app for the first time,it shows me an error. The error is: Unable to get property 'STS' undefined or null reference. If I refresh my app then the error disappears. </p>
  
  <p>I'm working with showWaitScreenWithNoClose() from sp.ui.dialog.js. This is my code in my document.ready:</p>
  
  <pre><code>loadScreen = SP.UI.ModalDialog.showWaitScreenWithNoClose("Loading","");
  </code></pre>
  
  <p>and yes I've added these scripts to my master-page:</p>
  
  <pre><code>&lt;script type="text/javascript" src="/_layouts/15/sp.ui.dialog.js"&gt;&lt;/script&gt;
  &lt;script type="text/javascript" src="/_layouts/15/ScriptResx.ashx?    culture=en%2Dus&amp;name=SP%2ERes"&gt;&lt;/script&gt;
  </code></pre>
  
  <p>So now is my question why do I get that error and how can I solve this? I'm using IE10 maybe that could be the problem.</p>