
PASS Observer with multiple thresholds. 
PASS First rAF. 
PASS document.scrollingElement.scrollTop = 120 
PASS document.scrollingElement.scrollTop = 160 
PASS document.scrollingElement.scrollTop = 200 
PASS document.scrollingElement.scrollTop = 240 
PASS document.scrollingElement.scrollTop = window.innerHeight + 140 
PASS document.scrollingElement.scrollTop = window.innerHeight + 160 
PASS document.scrollingElement.scrollTop = window.innerHeight + 200 
PASS document.scrollingElement.scrollTop = window.innerHeight + 220