- containsMouse property stays true after releasing a drag (it doesn't matter if you dropped it within a drop area or not) outside the mouse area until you move the cursor
- containsMouse property of other mouse areas (non-dragged one) will not be updated until you make a mouse click
- After releasing the drag, move the cursor, the containsMouse property of the dragged mouse area will be updated to false as mentioned above. But if you click the mouse, then the containsMouse property of the dragged mouse area will be set to true again, and it will stay true until you move the cursor again.
- If you drop the drag to a drop area that's also a mouse area, you will need to click that area twice to update the containsMouse property of that mouse area, but the containsMouse property of the dragged mouse area stays true until you move the cursor.
*I have attached a simple example file and a demo video that reveals the problems easily.