title: Changing background image on succesive Ajax requests causes multiple GETs for same image
body: <p>The title pretty much says it. I have an element that doesn't have a background image. I set one (a spinner) during an Ajax request using jQuery's css() method, then clear it with removeAttr("style") to revert back. Only one request is running at a time.</p>
  
  <p>This, however, causes a GET for the background image not just the first time, but later as well, but even then, not always. I may send, let's say, 5 requests and no GET for spinner.gif after the first, then another request and there will be one, then not for another 3 request, then GET for the next 2.</p>
  
  <p>If there was a GET for the image with every Ajax request, I'd understand, but it's kind of random.</p>
  
  <p>What am I missing here?</p>