title: how to get filename entered by user in "save as" dialog after javascript anchor.click()
body: <p>I use HTML5 anchor.download attribute for saving a file locally.</p>
  
  <p>The save dialog allows the user to change the file name but I can't find any record of this in anchor.</p>
  
  <pre><code>var anchor = document.createElement("A");
  anchor.href= (window.URL || window.webkitURL).createObjectURL(blob);
  anchor.download = filename;
  anchor.click();
  </code></pre>
  
  <p>How do I recover the changed file name after click()?</p>