Dragging menu items: how it works

The menu tree can be dragged with a mouse and with a finger. Inside is an ordinary sorting library, but two of its conditions are mandatory — and both were once broken.

ghostClass: "mi-ghost"      one token, not a list
emptyInsertThreshold: 15   otherwise an empty list cannot be dropped into

The class must be a SINGLE word: the library applies it directly, and a space inside a class name is an error that aborts the gesture. And an empty drop list must have a non-zero size, or there is nothing to aim at.