add_filter('swift_performance_cache_folder_prefix', 'swift_gdpr_cookie_prefix');
add_action('swift_performance_prebuild_cache_hit', 'swift_gdpr_cookie_prebuild'));

function swift_gdpr_cookie_prefix(){
    return (isset($_COOKIES['wp-gdpr-cookie']) && $_COOKIES['wp-gdpr-cookie'] == 'Y' ? 'accepted' : '');
}


function swift_gdpr_cookie_prebuild($permalink){
      // Add country code to prebuild header
      add_filter('swift_performance_prebuild_headers', function($headers){
            $headers['Cookie'] = 'wp-gdpr-cookie=Y';
            return $headers;
      });

      // Add country code to mobile prebuild header
      add_filter('swift_performance_mobile_prebuild_headers', function($headers){
            $headers['Cookie'] = 'wp-gdpr-cookie=Y';
            return $headers;
      });

      Swift_Performance::prebuild_cache_hit($permalink);
}