
State:
  [1] Stack of open elements,
  [2] List of active formatting elements,
  [3] Head element pointer,
  [4] Form element pointer,
  [5] Insertion mode
	-> in select
	-> in cell
	-> in row
	-> in table body
	-> in caption
	-> in column group
	-> in table
	-> in body

	-> in frameset
	-> in head
	-> before head

Algorithms [1] (can result in match or failure):
  Has an element in scope?
  Has an element in table scope?


