docs: private Integer getDecoratedComponentLayerInLayeredPane(JLayeredPane layeredPane) {
          Container ancestorInLayer = decoratedComponent;
          while (!layeredPane.equals(ancestorInLayer.getParent())) {
              ancestorInLayer = ancestorInLayer.getParent();
          }
  
          return (layeredPane.getLayer(ancestorInLayer) + DECORATION_LAYER_OFFSET);
      }