title: nomodule and "type="module" works differently for IE 11
body: <p>I was testing the functionality of <code>nomodule</code> and <code>type="module"</code> in an app. I used chrome which only downloaded the file in <code>type="module"</code> tag, which was expected. But when I tested it in IE 11, to my amusement files where downloaded from both the script tags.</p>
  
  <p>I have attached the images for reference. Please help me understand this behaviour.</p>
  
  <h2>index.html</h2>
  
  <pre><code>&lt;meta charset="utf-8"&gt;
  &lt;title&gt;custom-element demo&lt;/title&gt;
  &lt;script src="https://unpkg.com/vue"&gt;&lt;/script&gt;
  &lt;script nomodule src="http://localhost:85/email-compose-legacy.min.js"&gt;&lt;/script&gt;
  &lt;script type="module" src="http://localhost:85/email-compose.min.js"&gt;&lt;/script&gt;
  
  &lt;email-compose-legacy&gt;&lt;/email-compose-legacy&gt;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/xROwA.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/xROwA.png" alt="network tab in chrome"></a></p>
  
  <p><a href="https://i.stack.imgur.com/Ozjlc.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Ozjlc.png" alt="network tab in IE 11"></a></p>