title: iframe not showing content in html
body: <p><strong>toonzaal.php</strong> (html page but php code included -> thats why .php)</p>
  
  <pre><code>&lt;iframe data-src="toonzaal.html" scrolling="no" frameborder="0" style="height:600px"&gt;&lt;/iframe&gt;  
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/jwdZt.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/jwdZt.jpg" alt="enter image description here"></a></p>
  
  <p>The empty space is the iframe I guess but don't know why nothing more is showing.</p>
  
  <p><strong>toonzaal.html</strong></p>
  
  <p>this is a slider (pictures) that I want to show smaller in the toonzaal.php page</p>
  
  <p><a href="https://i.stack.imgur.com/pjctU.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/pjctU.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/ZXq9L.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ZXq9L.jpg" alt="enter image description here"></a></p>
  
  <p><strong>Folder structure</strong></p>
  
  <p><a href="https://i.stack.imgur.com/nR8P8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/nR8P8.png" alt="enter image description here"></a></p>