title: Blob download works in Chrome but not in firefox
body: <p>I am using the following code snippet to download a blob formed form ArrayBuffer</p>
  
  <pre><code>                       let blob = new window.Blob(dataOrg);
                         let anchor = document.createElement('a');
                         anchor.href = URL.createObjectURL(blob);
                         anchor.download = "downloadssss";
                         anchor.textContent = 'XXXXXXX';
  
                         if (anchor.click) {
                             anchor.click();
                         } else {
                             var evt = document.createEvent('MouseEvents');
                             evt.initMouseEvent('click', true, true, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null);
                             evt.initMouseEvent('click', true, true, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null);
                             anchor.dispatchEvent(evt);
                         }  
  </code></pre>
  
  <p>This code works in chrome but doesnot do anything in Firefox. The content i am trying to download is a mp4 file sent through PeerJs.</p>