private static @Nullable Color extractUnselectedBackground(boolean isSelected, Supplier<? extends Component> supplier) {
    if (ExperimentalUI.isNewUI() && isSelected) {
      Component component = supplier.get();
      if (component != null) {
        return component.getBackground();
      }
    }
    return null;
  }
private static @Nullable Color extractUnselectedBackground(boolean isSelected, Supplier<? extends Component> supplier)