title: How do I get the background-position-y in firefox using jQuery?
body: <pre><code>$(elem).css('backgroundPositionY')
  </code></pre>
  
  <p>does it on chrome, ie, and safari, but not Firefox (nor Opera I believe).  You'd think jQuery would have a polyfill but it doesn't, as of 1.5.  How can I easily get the background Y position for e.g. background animations (for e.g. parallax)?</p>
  
  <p><strong>EDIT</strong>: <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=550426">Tell Mozilla</a> you want <code>background-position-[x,y]</code> support. (use the "vote" feature, not comment, unless you have something prescient to add). Bug has been open since 2010 tho (3 years now) so don't hold your breath for a fix. :)</p>