private static @Nullable URL builtinServerUrl(@NotNull URL url) {
    Url parsedUrl = Urls.parseEncoded(url.toExternalForm());
    if (parsedUrl == null) {
      return null;
    }
    BuiltInServerManager builtInServerManager = BuiltInServerManager.getInstance();
    if (!builtInServerManager.isOnBuiltInWebServer(parsedUrl)) {
      return null;
    }
    try {
      return new URL(builtInServerManager.addAuthToken(parsedUrl).toExternalForm());
    }
    catch (MalformedURLException e) {
      DocumentationManager.LOG.warn(e);
      return null;
    }
  }
private static @Nullable URL builtinServerUrl(@NotNull URL url)