It would be nice if the popupshowing and popupshown events included the coordinates of the mouse at the time of creation. I will need this information in order to make outliner tooltips useful, so that you can determine the cell that the mouse is over. I have a patch.
sr=hyatt, although we really should get the "21" constant into the nsLookAndFeel object.
ok, looks good but please double check computing of y coordinate I recall there were already |y += 21| in nsXULPopupListener.cpp r=varga