@Override
  public void saveProperties(@NotNull UnknownSourceRootTypeProperties<?> properties, @NotNull Element sourceRootTag) {
    Object data = properties.getPropertiesData();
    if (data instanceof Element) {
      JDOMUtil.copyMissingContent((Element)data, sourceRootTag);
    }
  }
@Override
  public void saveProperties(@NotNull UnknownSourceRootTypeProperties<?> properties, @NotNull Element sourceRootTag)