in static/studio/static/js/FancyZoom.js [640:655]
function setOpacity(opacity, theID) {
var object = document.getElementById(theID).style;
// If it's 100, set it to 99 for Firefox.
if (navigator.userAgent.indexOf("Firefox") != -1) {
if (opacity == 100) { opacity = 99.9999; } // This is majorly awkward
}
// Multi-browser opacity setting
object.filter = "alpha(opacity=" + opacity + ")"; // IE/Win
object.opacity = (opacity / 100); // Safari 1.2, Firefox+Mozilla
}