code: function focusBody() {
          // Fix for a focus bug in FF 3.x where the body element
          // wouldn't get proper focus if the user clicked on the HTML element
          if (!window.Range.prototype.getClientRects) { // Detect getClientRects got introduced in FF 4
            editor.on('mousedown', function (e) {
              if (!isDefaultPrevented(e) && e.target.nodeName === "HTML") {
                var body = editor.getBody();
  
                // Blur the body it's focused but not correctly focused
                body.blur();
  
                // Refocus the body after a little while
                Delay.setEditorTimeout(editor, function () {
                  body.focus();
                });
              }
            });
          }
        }
docs: Firefox 3.x has an issue where the body element won't get proper focus if you click out
  side it's rectangle.