title: Youtube embed code does not work in html for firefox
body: <p>I'm brand new to HTML and trying to develop some basic skills and build a knowledge base by writing example pages.  I copy and paste the default youtube embed code and paste it in my code.  If I use the old code, I get a big white box.  The new code yields a box containing dialog which states that firefox could not find the page.  Chrome loads the object with no issues.  Here is the code:</p>
  
  <pre><code>&lt;iframe width="560" height="315" src="https://www.youtube.com/embed/OIDnYMODZAQ" frameborder="0" allowfullscreen&gt;&lt;/iframe&gt;
  </code></pre>