@Contract(pure = true)
  public static @NotNull Collector<HtmlChunk, ?, HtmlChunk> toFragment() {
    return Collector.of(HtmlBuilder::new, HtmlBuilder::append, HtmlBuilder::append, HtmlBuilder::toFragment);
  }
@Contract(pure = true)
  public static @NotNull Collector<HtmlChunk, ?, HtmlChunk> toFragment()