Open Radar

 
Summary: Changing the dragging destination feedback style on an NSTableView instance to NSTableViewDraggingDestinationFeedbackStyleNone while a drag operation is in progress will "freeze" the drop indicator at its last shown position. Further movement and ending the drag do not clear the drawn indicator.

Steps to Reproduce:
1. Implement a basic app that allows drag & drop inside an NSTableView. (See attached for example.)
2. On a custom NSTableView subclass, implement -draggingSession:movedToPoint: to set the feedback style to NSTableViewDraggingDestinationFeedbackStyleNone.
3. Run the app and move a drag inside the table view so that -draggingSession:movedToPoint: is called.

Expected Results: The drop indicator is cleared when the feedback style changes; no further drop indicators are drawn.

Actual Results: The drop indicator is drawn where expected, then frozen there. None of the following clear the frozen indicator:
* Moving the drag further
* Ending the drag
* Starting a new drag
* Selecting table view cells around the drawn indicator
* Changing the active application

Regression: Unknown.

Notes: Sample application attached.