function handleEvent(e) {
  // e.timeStamp has different precision in Firefox v Chrome
  var time;
  if (window.performance) {
    time = (window.performance.now() / 1000).toFixed(6);
  } else {
    time = ((Date.now() - start) / 1000).toFixed(3);
  }
  data.innerHTML = '<span class = "time">' + time + '</span>' + 's: ' +
    e.type + '<br>' + data.innerHTML;
}
// for browsers that don't support window.performance
for browsers that don't support window.performance
for browsers that don ' t support window . performance
function handleEvent(e) {
  var time;
  if (window.performance) {
    time = (window.performance.now() / 1000).toFixed(6);
  } else {
    time = ((Date.now() - start) / 1000).toFixed(3);
  }
  data.innerHTML = '<span class = "time">' + time + '</span>' + 's: ' +
    e.type + '<br>' + data.innerHTML;
}
function handleEvent ( e ) { var time ; if ( window . performance ) { time = ( window . performance . now ( ) / 1000 ) . toFixed ( 6 ) ; } else { time = ( ( Date . now ( ) - start ) / 1000 ) . toFixed ( 3 ) ; } data . innerHTML = '<span class = "time">' + time + '</span>' + 's: ' + e . type + '<br>' + data . innerHTML ; }
for browsers that don't support window.performance
for browsers that don ' t support window . performance
// e.timeStamp has different precision in Firefox v Chrome