docs: private static List<String> asStringList(final Object pages) {
          if (pages instanceof String) {
              return Collections.singletonList((String) pages);
          } else if (pages instanceof Collection) {
              ArrayList<String> strings = new ArrayList<>();
              for (Object o : ((Collection) pages)) {
                  if (o instanceof String) {
                      strings.add((String) o);
                  }
              }
              if (strings.size() < 1) {
                  return null;
              }
              return strings;
          }
          return null;
      }