@Contract(pure = true)
  public @NotNull OptPane append(@NotNull OptRegularComponent @NotNull ... components) {
    var newComponents = new ArrayList<>(components());
    ContainerUtil.addAll(newComponents, components);
    return new OptPane(newComponents);
  }
@Contract(pure = true)
  public @NotNull OptPane append(@NotNull OptRegularComponent @NotNull ... components)