We need to handle the backbuffer before we fire the loadend event. Otherwise listeners that call e.g. mergeNewParams() will cause the backbuffer removal code to fail, because tile.imgDiv (and hence this._transitionElement) will be null.
We need to handle the backbuffer before we fire the loadend event. Otherwise listeners that call e.g. mergeNewParams() will cause the backbuffer removal code to fail, because tile.imgDiv (and hence this._transitionElement) will be null.