showWhenUnlinked property

Whether to show the widget's contents when there is no corresponding CompositedTransformTarget with the same link.

When the widget is linked, the child is positioned such that it has the same global position as the linked CompositedTransformTarget.

When the widget is not linked, then: if showWhenUnlinked is true, the child is visible and not repositioned; if it is false, then child is hidden.