576c0952_7_8_Drag_and_drop___HTML5__Target
[Event Name] dragenter [Bubbles?] ✓ Bubbles [Cancelable?] ✓ Cancelable [dataTransfer] Empty [effectAllowed] Same as last event [dropEffect] Based on effectAllowed value [Default Action] Reject immediate user selection as potential target element [Target] 
Immediate user selection or the body element
7.8 Drag and drop — HTML5