$0This property and FirstChild won't take you through all the elements. When loading the following code:$0
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$0<HTML>
<BODY>
<CODE>Computer code</CODE>
<BR />
<KBD>Keyboard input</KBD>
</BODY>
</HTML>
NextSibling is null in the element CODE. FirstChild is as well null, and the Parent is BODY, such a way that you will never reach KBD.
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