if (!aElement) return false;    
function isElementVisible(aElement){  // * When an element is hidden, the width and height of its boxObject  //   are set to 0  // * css-visibility (unlike css-display) is inherited.  var bo = aElement.boxObject;  return (bo.height != 0 && bo.width != 0 &&          document.defaultView                  .getComputedStyle(aElement, null).visibility == "visible");}
5459	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/5459/bd2b254d12ebf93d37bbbce6eba176b7bad15131/utilityOverlay.js/clean/browser/base/content/utilityOverlay.js