Im using a Mac Book Pro. When dragging assets to the top the asset disappears, but I can see the z-order is set correctly. The asset no longer appears until I switch to another panel (90% of the time) otherwise I have to restart the app to see the order.
Steps to reproduce
Add a character ( head, torso, left bicep, right bicep, etc ) I have 14 items, so the scroll bar is visible. Head is at the bottom
Head is at the bottom
Drag head to top ( notice you can see the top so you drag at the top of the frame )
Drop the head on the first item.
Head disappears. On the Sc