[fullscreen] Need a linke for the concept "tree order" in "removing steps" (#7)

I was confused about the meaning of "tree order" in the steps of "removing steps" until I see the link of "tree order" in "exit fullscreen".

I think it would be clearer if that term has link everywhere it appears, since theoretically there are at least three different common "tree order"s.

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fullscreen/issues/7