invalid drop event triggered without drop combined with sortable

[Παραστατίδης Νίκος]

jQuery UI 1.12.1

jQuery 3.3.1 fiddle: ​https://jsfiddle.net/paranic/xpvt214o/362238/

reproduce steps

1. drag an element from the sortable to the drop area.
2. drag the dropped element from the droppable area to the sortable and beyond and then drag it back to the droppable area without dropping it (do not mouse up)

as you can see it will trigger the drop event and the element is still under my mouse but a copy of it is dropped on the droppable area.