web duper

// Detect file input support
var isFileInputSupported = (function () {
 // Handle devices which falsely report support
 if (navigator.userAgent.match(/(Android (1.0|1.1|1.5|1.6|2.0|2.1))|(Windows Phone (OS 7|8.0))|(XBLWP)|(ZuneWP)|(w(eb)?OSBrowser)|(webOS)|(Kindle\/(1.0|2.0|2.5|3.0))/)) {
   return false;
 }
 // Create test element
 var el = document.createElement("input");
 el.type = "file";
 return !el.disabled;
})();

// Add 'fileinput' class to html element if supported
if (isFileInputSupported) {
 document.documentElement.className += " fileinput";
}