code: public static SanitizedContent cleanHtml(
        String value, Dir contentDir, Collection<? extends OptionalSafeTag> optionalSafeTags) {
      return UnsafeSanitizedContentOrdainer.ordainAsSafe(
          stripHtmlTags(value, TagWhitelist.FORMATTING.withOptionalSafeTags(optionalSafeTags), true),
          ContentKind.HTML,
          contentDir);
    }
docs: Normalizes the input HTML of a given directionality while preserving "safe" tags.
  
  @param optionalSafeTags to add to the basic whitelist of formatting safe tags
  @return the normalized input, in the form of {@link SanitizedContent} of {@link
  ContentKind#HTML}