@Contract("null, _ -> null")
  @Nullable
  public static String mapUrl(@Nullable String url, @NotNull Region region) {
    if (url != null) {
      for (Pair<String, String> pair : ourCache.get(region)) {
        String pattern = pair.getFirst();
        int entry = Strings.indexOfIgnoreCase(url, pattern, 0);
        if (entry >= 0) {
          String replacement = pair.getSecond();
          return url.substring(0, entry) + replacement + url.substring(entry + pattern.length());
        }
      }
    }
    return url;
  }
@Contract("null, _ -> null")
  @Nullable
  public static String mapUrl(@Nullable String url, @NotNull Region region)