docs: protected BlockBox createBlock(BlockBox parent, Element n, boolean replaced)
      {
          BlockBox root;
          if (replaced)
          {
              BlockReplacedBox rbox = new BlockReplacedBox((Element) n, (Graphics2D) parent.getGraphics().create(), parent.getVisualContext().create());
              rbox.setViewport(viewport);
              rbox.setContentObj(new ReplacedImage(rbox, rbox.getVisualContext(), baseurl, n.getAttribute("src")));
              root = rbox;
          }
          else
          {
              root = new BlockBox((Element) n, (Graphics2D) parent.getGraphics().create(), parent.getVisualContext().create());
              root.setViewport(viewport);
          }
          root.setBase(baseurl);
          root.setParent(parent);
          root.setContainingBlockBox(parent);
          root.setClipBlock(viewport);
          root.setOrder(next_order++);
          return root;
      }