title: Facebook page embed iframe doesn't fill container width
body: <p>I added an iframe of wikipedia to demonstrate the problem I have.<br>
  The Wiki iframe is displayed correctly like it suppose to, but the facebook iframe isn't.</p>
  
  <p><a href="https://i.stack.imgur.com/BoHX9.png" rel="noreferrer"><img src="https://i.stack.imgur.com/BoHX9.png" alt="enter image description here"></a>
  <a href="https://i.stack.imgur.com/t78LS.png" rel="noreferrer"><img src="https://i.stack.imgur.com/t78LS.png" alt="enter image description here"></a></p>
  
  <p><strong>HTML:</strong></p>
  
  <pre><code>   &lt;div class="iframe-fb-container mt-4"&gt;
        &lt;iframe class="iframe-fb" width="450" height="700" style="border:1px solid black;overflow:hidden" scrolling="yes" frameborder="0" allowTransparency="true" allow="encrypted-media" src="https://www.facebook.com/plugins/page.php?href=https://www.facebook.com/Microsoft/&amp;tabs=timeline%2Cevents%2Cmessages&amp;width=450px&amp;height=700px&amp;small_header=false&amp;adapt_container_width=true&amp;hide_cover=false&amp;show_facepile=true&amp;appId=2235597906716847"&gt;&lt;/iframe&gt;
        &lt;iframe class="iframe-fb" width="450" height="700" style="border:1px solid black;overflow:hidden" scrolling="yes" frameborder="0" allowTransparency="true" allow="encrypted-media" src="https://fr.wikipedia.org/wiki/Main_Page"&gt;&lt;/iframe&gt;
     &lt;/div&gt;
  </code></pre>
  
  <p><strong>CSS:</strong></p>
  
  <pre><code>.iframe-fb-container {
      border: 1px solid blue;
   }
  
   .iframe-fb {
      width: 100%;
      }
  </code></pre>
  
  <p>As you can see I am asking facebook an iframe with width of <strong>450px</strong> and in the images attached the width of the emulator is <strong>375px</strong>, but still the fb iframe doesn't fill it container like the wikipedia iframe does.</p>
  
  <p>How can I make fb iframe to fill it container?</p>