* The HTTP {@code Keep-Alive} header field name.
   *
   * @since 31.0
   */
  public static final String KEEP_ALIVE = "Keep-Alive";
  /**
   * The HTTP <a href="https://github.com/WICG/nav-speculation/blob/main/no-vary-search.md">{@code
   * No-Vary-Seearch}</a> header field name.
   *
   * @since 32.0.0
   */
  public static final String NO_VARY_SEARCH = "No-Vary-Search";
  /**