I have found something which may be a bug or may be me. I have set my menu to have 0ms on all transitions (I think) so that it responds instantly as the mouse moves over items.
This doesn’t seem to work when the mouse moves away from an item which has sub-items/dropdown - there is a short delay before it disappears.
See screen movie to see it happen: https://youtu.be/p9IbYByYo2A
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