public static function enable_direct_download() {
    global $pagenow;

    // This check fires on every page load, so keep the scope small
    if ( $pagenow === 'tools.php' && isset( $_GET['report'] ) ) { // phpcs:ignore WordPress.CSRF.NonceVerification.NoNonceVerification

      // Next check if the request for a report is valid
      // - user be administrator
      // - filename must be of correct form, e.g. 2016-09.html
      if ( current_user_can( 'administrator' ) &&
          preg_match( '/[0-9]{4}-[0-9]{2}\.html/', $_GET['report'], $matches) ) { // phpcs:ignore WordPress.CSRF.NonceVerification.NoNonceVerification

        header('Content-type: text/html');
        // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_read_readfile
        readfile( '/data/slog/html/goaccess-' . $matches[0] );
        // Stop executing WordPress once a HTML file has been sent
        exit();
      } else {
        // Yield an error if ?report was requested, but without permissions
        // or with wrong filename.
        exit( 'Report file not found.' );
      }
    }
  }