OnPointerEnter not working anymore? It became OnPointerClick?

Hi There,

I was using OnPointerEnter before it works great. However after upgrading from 5.4.1f1 to 5.5.0f3 for some reason it OnPointerEnter to OnPointerExit.

 public void OnPointerEnter(PointerEventData eventData)
     {
 //T$$anonymous$$s does not trigger on PhysicRaycaster... what is going on?
         Debug.Log("Enter");
     }

I have to click it instead of hovering it.