Important UPDATE: CSSOM View Module W3C Working Draft 22 February 2008 has clarified the specifications regarding offsetParent, offsetLeft, offsetTop and many other attributes. So, this testcase is no longer reliable. Nevertheless, I keep it for reference. March 28th 2008.

Instructions:
Hover the mouse over the absolutely positioned <p> (white background color)
Expected results: the offsetParent node should NOT be the body node. It should be undefined.

Position output data table
X mouse coordinate within the whole width of the document Opera 7 and higherMozilla 1.0+ evt.pageX
Y mouse coordinate within the whole height of the document Opera 7 and higherMozilla 1.0+ evt.pageY
X mouse coordinate within a positioned element otherwise within its closest positioned containing element Mozilla 1.0+evt.layerX
Current target element's tagname
Current target element's id
Current target's offsetParent tagname
Current target's offsetParent id
Y mouse coordinate within a positioned element otherwise within its closest positioned containing element Mozilla 1.0+ evt.layerY

This <p> is absolutely positioned. This is the <p> for testing.