every extractor asked routeOf, and routeOf does five ax.find calls. on
web each find walks the document and every shadow root beneath it, so
the spec cost 110 tree walks a step; homeCards was parsed four times
over. now 5 and once.
keyed on the identity of the state object because both hosts build a new
one per step and hand that one object to every getter, so it cannot
outlive its frame. holding the reference is what keeps that true rather
than likely.