title: SVG mask clipping not working in Firefox
body: <p>I've been trying to achieve this scrolling effect by using SVG masks. It works perfectly fine in Chrome, although it doesn't seem to work in Firefox. I've created a dabblet to show the behaviour I'm getting: <a href="http://dabblet.com/gist/83bf9a8708193634892e" rel="nofollow">http://dabblet.com/gist/83bf9a8708193634892e</a></p>
  
  <p>The proper way to create clipping masks differs between browsers (more information about this can be found <a href="http://www.html5rocks.com/en/tutorials/masking/adobe/" rel="nofollow">here</a>). Of course I've used both indicated methods, for Chrome and Firefox.</p>
  
  <p>The SVG file looks something like this: </p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"&gt;
  &lt;svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
   width="138px" height="522.457px" viewBox="81 -111.228 138 522.457" enable-background="new 81 -111.228 138 522.457"
   xml:space="preserve"&gt;
    &lt;path id="svgClip" d="M215.546,73.573c-4.565-16.493-28.671-31.462-35.774-40.851c-7.104-9.389-5.964-39.836-5.964-39.836v-52.268
  c0,0-0.254-19.917-0.254-21.821c2.03,0,1.396-3.679,1.396-3.679s0-9.896,0-12.052c0-2.157-2.03-2.41-2.03-2.41v-7.823
  c-0.509-4.061-5.242-4.061-5.242-4.061H150.93h-1.86h-16.747c0,0-4.735,0-5.243,4.061v7.823c0,0-2.03,0.254-2.03,2.41
  s0,12.052,0,12.052s-0.634,3.679,1.395,3.679c0,1.903-0.253,21.821-0.253,21.821v52.268c0,0,1.142,30.447-5.962,39.836
  c-7.104,9.388-31.208,24.357-35.775,40.851c-4.567,16.492-3.552,45.925-2.792,69.268l4.069,249.541c0,0-1.489,17.889,14.278,18.397
  c14.653,0.798,39.683,0.339,49.664,0.108c8.501,0.23,30.053,0.689,44.705-0.108c18.605-1.015,16.94-19.623,16.94-19.623
  l7.02-248.315C219.1,119.498,220.114,90.065,215.546,73.573z"/&gt;
    &lt;mask id="mask" maskUnits="userSpaceOnUse" maskContentUnits="userSpaceOnUse" transform="scale(1)"&gt;
      &lt;path d="M215.546,73.573c-4.565-16.493-28.671-31.462-35.774-40.851c-7.104-9.389-5.964-39.836-5.964-39.836v-52.268
  c0,0-0.254-19.917-0.254-21.821c2.03,0,1.396-3.679,1.396-3.679s0-9.896,0-12.052c0-2.157-2.03-2.41-2.03-2.41v-7.823
  c-0.509-4.061-5.242-4.061-5.242-4.061H150.93h-1.86h-16.747c0,0-4.735,0-5.243,4.061v7.823c0,0-2.03,0.254-2.03,2.41
  s0,12.052,0,12.052s-0.634,3.679,1.395,3.679c0,1.903-0.253,21.821-0.253,21.821v52.268c0,0,1.142,30.447-5.962,39.836
  c-7.104,9.388-31.208,24.357-35.775,40.851c-4.567,16.492-3.552,45.925-2.792,69.268l4.069,249.541c0,0-1.489,17.889,14.278,18.397
  c14.653,0.798,39.683,0.339,49.664,0.108c8.501,0.23,30.053,0.689,44.705-0.108c18.605-1.015,16.94-19.623,16.94-19.623
  l7.02-248.315C219.1,119.498,220.114,90.065,215.546,73.573z"/&gt;
    &lt;/mask&gt;
  &lt;/svg&gt;
  </code></pre>
  
  <p>What am I doing wrong when trying to implement it on Firefox?
  As usual, any kind of hint or help will be very much appreciated!</p>