code: public ChromeOptions addEncodedExtensions(List<String> encoded) {
      for (String extension : encoded) {
        checkNotNull(extension);
      }
      extensions.addAll(encoded);
      return this;
    }
docs: Adds a new Chrome extension to install on browser startup. Each string data should
  specify a Base64 encoded string of packed Chrome extension (CRX file).
  
  @param encoded Base64 encoded data of the extensions to install.