docs: public ElementUI materialize(ElementUI parent) {
          boolean isDesktop = parent instanceof ElementDesktop;
  
          if (isDesktop) {
              parent.getDefinition().initElement(parent, root);
          }
  
          materializeChildren(parent, root, !isDesktop);
          ElementUI element = parent.getLastVisibleChild();
          
          if (element != null) {
              element.getRoot().activate(true);
          }
  
          return element;
      }