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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Using previousElementSibling and insertBefore

Brian Shelton
Brian Shelton
1,270 Points

Why is first child li moved to bottom?

I understand that the first child li would have previousSibling == null, but why exactly would it be moved to the bottom of the list? The explanation wasn't clear in the video.

1 Answer

Nour El-din El-helw
Nour El-din El-helw
8,241 Points

I also had the same problem but I checked the MDN page for insertBefore(), it says "If the reference node is null, the specified node is added to the end of the list of children of the specified parent node." So..yeah, make sure to read the documentation for anything you're stuck with.