text: 
  
  /**
   * Ajax clear all cached.
   *
   * @returns {undefined}
   */
  function rdDownloadsSettingsAjaxClearCache() {
      var $ = jQuery.noConflict();
  
      $('#rd-downloads-settings-clear-cache').off('click');
      $('#rd-downloads-settings-clear-cache').on('click', function(e) {
          e.preventDefault();
  
          $(this).find('.icon-correct').remove();
          $(this).prepend('<i class="fas fa-spinner fa-pulse icon-loading"></i> ');
  
          $.ajax({
              'url': ajaxurl,
              'method': 'POST',
              'data': 'security=' + encodeURIComponent(RdDownloadsSettings.nonce) + '&action=RdDownloadsSettingsClearCache',
              'dataType': 'json'
          })
          .done(function() {
              $('#rd-downloads-settings-clear-cache .icon-loading').remove();
              $('#rd-downloads-settings-clear-cache').prepend('<i class="fas fa-check icon-correct"></i>');
          })
          .fail(function() {
              $('#rd-downloads-settings-clear-cache .icon-loading').remove();
          })
          .always(function(jqXHR, textStatus, data) {
              if (typeof(jqXHR) !== 'undefined' && typeof(jqXHR.responseJSON) !== 'undefined') {
                  var response = jqXHR.responseJSON;
              } else {
                  var response = jqXHR;
              }
              if (typeof(response) === 'undefined') {
                  response = {};
              }
  
              if (typeof(response.form_result_msg) !== 'undefined') {
                  alert(response.form_result_msg);
              }
  
              response = undefined;
          });
      });
  }// rdDownloadsSettingsAjaxClearCache
  
  
  // on dom ready --------------------------------------------------------------------------------------------------------
  (function($) {
      rdDownloadsSettingsAjaxClearCache();
  })(jQuery);