title: Firefox / Firebug's "console.log" always returns 'undefined'
body: <p>Since yesterday, for some reason each time I try to display the console log in Firefox I get an <em>undefined</em> instead:</p>
  <p><a href="https://i.stack.imgur.com/5LPZU.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/5LPZU.jpg" alt="Enter image description here" /></a></p>
  <p>I use this tool quite often, and just recently I saw that this is not working anymore. I have seem similar questions on Stack Overflow, but none of them with an answer to fix it.</p>
  <p>This is what I have done so far to try fix it. I have already</p>
  <ul>
  <li>Reinstalled Firebug</li>
  <li>Reinstalled Firefox</li>
  </ul>
  <p>And nothing seems to work. However, when I type &quot;console&quot; and hit the run button I get:</p>
  <p>Is it a set up that I have to change?</p>
  <p><a href="https://i.stack.imgur.com/Z1Igx.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Z1Igx.jpg" alt="Enter image description here" /></a></p>