Simulate Click inside Gmail

gistfile1.js

simulateClick = null;
function simulateClick() {
  var evt = document.createEvent("MouseEvents");
  evt.initMouseEvent("mousedown", true, true, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null);
  var cb = document.getElementById("canvas_frame").contentWindow.document.getElementById(":pg");
  var canceled = !cb.dispatchEvent(evt);
   console.log("innerText: " + cb.innerHTML);
   console.log("class: " + cb.class);
  if(canceled) {
    // A handler called preventDefault
    console.log("canceled");
  } else {
    // None of the handlers called preventDefault
    console.log("not canceled");
  }
}

simulateClick();