public TextContentBuilder removingIndents(String indentChars) {
    Set<Character> set = new HashSet<>(this.indentChars);
    for (int i = 0; i < indentChars.length(); i++) {
      set.add(indentChars.charAt(i));
    }
    return new TextContentBuilder(classifier, set, suffixChars);
  }
public TextContentBuilder removingIndents(String indentChars)