Below is the start of the code sample for the popupLogin example. Note that the popup is inside of a popup. The outer popup has an id of popupMenu so I am thinking there was a cut and paste mistake when the example was created. The example works because the definition of popupMenu is present. But, I can't see why there would be a need for the popup with an id of popupMenu wrapped around the popup with an id of popupLogin.