private boolean calcHidden() {
    List<Language> languages = new ArrayList<>(Language.getRegisteredLanguages());
    languages.sort((o1, o2) -> {
      // Java supports most of refactorings,
      // so it is faster to just check it first without loading all language extensions
      if ("JAVA".equals(o1.getID())) return -1;
      if ("JAVA".equals(o2.getID())) return 1;

      return o1.getID().compareTo(o2.getID());
    });

    for (Language l: languages) {
      if (isAvailableForLanguage(l)) {
        return false;
      }
    }
    return true;
  }
private boolean calcHidden()