How to change the icon at onStart event to indicate not-allowed?

[cortexrd]

Is it possible to change the drag icon from that dotted rectangle to another icon?

Sometimes, I'd like to have a visual indicator that a specific item it not draggable. I don't want to disable the drag-n-drop completely for that item, I just want to add a visual indication that it's "not-allowed" (circle+diagonal bar), and return false upon onMove event instead.

I tried setting evt.originalEvent.dataTransfer.effectAllowed = 'none'; but it has no effect.

Any help will be appreciated.
Norm