gdk:drop-status (drop actions preferred)

drop -- a gdk:drop object
actions -- a gdk:drag-action value with the supported actions of the destination, or :none to indicate that a drop will not be accepted
preferred -- a gdk:drag-action value with the unique action that is a member of actions indicating the preferred action

Selects all actions that are potentially supported by the destination. When calling this function, do not restrict the passed in actions to the ones provided by the gdk:drop-actions function. Those actions may change in the future, even depending on the actions you provide here.

The preferred action is a hint to the drag'n'drop mechanism about which action to use when multiple actions are possible.

This function should be called by drag destinations in response to :enter or :motion events. If the destination does not yet know the exact actions it supports, it should set any possible actions first and then later call this function again.