title: Find what happens when you click an HTML button
body: <p>For example, you have this script that adds an event listener to a button like this:</p>
  <pre><code>document.getElementById(&quot;myBtn&quot;).addEventListener(&quot;click&quot;, function() {
    document.getElementById(&quot;demo&quot;).innerHTML = &quot;Hello World&quot;;
  });
  </code></pre>
  <p>How would I see that code in a website, so I can execute the code from the console?</p>