Reproduce step :
1.drag the item out of the browser body.
It's cuasing by emulating the mouse event from touch event,
it's not firing mouse event after we drage out of the body in mouse event.
in domiso.js ,
When we try to emulate mouse event , the "document.elementFromPoint()" return a null
1. Refine the code in createJQEvent to check if target is null instead of calling undefined object.
2. not firing mousemove when the target is null ( more reasonable for me. )