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Both document.elementFromPoint() and document.caretPositionFromPoint() take viewpoint coordinates, and return null if the coordinates given identify a point outside of the visible viewport. This prevents using these methods for hit testing elements elsewhere in the document. We've had a few feature requests for equivalent methods which operate within the document's coordinate space, and personally I think it's a good idea. Implementing such methods in WebKit would be pretty straightforward. I'll refrain from suggesting names; feel free to bikeshed! :) Filed as requested in http://lists.w3.org/Archives/Public/www-style/2012Oct/0690.html