title: Paste document files in javascript
body: <p>I'd like to paste file to server from client desktop using javascript. 
  So I added a listener on paste event: </p>
  
  <pre><code>document.addEventListener('paste', function(e) {
          var files = {};
          if(window.clipboardData){ // IE
              files = window.clipboardData.files;
          }
          else {
              files = e.clipboardData.files;
          }
          //...some functions using files
  });
  </code></pre>
  
  <p>Event fires correctly but the problem is - e.clipboardData.files has always length of 0. I'm using ctrl+c on my desktop's .docx file. Am I missing something? My browsers are Firefox Quantum 57 and Google Chrome 60 on Ubuntu 16.04.</p>