The GtkTreeListModelCreateModelFunc returns
a new reference.
* If it does not have children but may get children later, it should return
* an empty model that is filled once children arrive.
*
- * Returns: (nullable): The model tracking the children of @item or %NULL if
+ * Returns: (nullable) (transfer full): The model tracking the children of @item or %NULL if
* @item can never have children
*/
typedef GListModel * (* GtkTreeListModelCreateModelFunc) (gpointer item, gpointer user_data);