private function getWhitelistRegExp($isLibrary) {
    $whitelist = $this->h5pF->getWhitelist($isLibrary, H5PCore::$defaultContentWhitelist, H5PCore::$defaultLibraryWhitelistExtras);
    return array($whitelist, '/\.(' . preg_replace('/ +/i', '|', preg_quote($whitelist)) . ')$/i');
  }