[UxmlAttribute]public bool showAddRemoveFooter { get; set; }

The default value is . When this property is set to , Unity adds a footer under the scroll view. This footer contains two buttons: A "+" button. When clicked, it adds a single item at the end of the list view. A "-" button. When clicked, it removes all selected items, or the last item if none are selected. If the _makeFooter callback is set, it will override this property.