View difference between Paste ID: da4EMTLQ and hXPpVYgu

 <!doctype html>
 <html>
 <head>
     <script type="text/javascript" src="http://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
 </head>
 <body>
     <input type="date" value="2014-05-22" />
 
     <button id="js-btn-test" type="button">
         An amazing button
     </button>
 
     <div id="js-test-output">
         Test output:
     </div>
 
     <script type="text/javascript">
         var btn = document.getElementById("js-btn-test");
         var output = document.getElementById("js-test-output");
 
         btn.addEventListener("click", function () {
          output.innerHTML += "<p>Clicked</p>";
         });
 
-        document.addEventListener("mouseup", function () {
+
             return false;
         });
     </script>
 </body>
-            evt.preventDefault();
+