diff --git a/core/misc/ajax.js b/core/misc/ajax.js
index b63bc03..167654d 100644
--- a/core/misc/ajax.js
+++ b/core/misc/ajax.js
@@ -312,25 +312,25 @@
     /**
      * @type {object}
      */
-    this.element_settings = element_settings;
+    this.$element_settings = element_settings;
 
     // If there isn't a form, jQuery.ajax() will be used instead, allowing us to
     // bind Ajax to links as well.
-    if (this.element && this.element.form) {
+    if (this.$element && this.element.form) {
 
       /**
        * @type {jQuery}
        */
-      this.$form = $(this.element.form);
+      this.$form = this.$element.form;
     }
 
     // If no Ajax callback URL was given, use the link href or form action.
     if (!this.url) {
-      var $element = $(this.element);
+      var $element = this.$element;
       if ($element.is('a')) {
         this.url = $element.attr('href');
       }
-      else if (this.element && element.form) {
+      else if (this.$element && $element.form) {
         this.url = this.$form.attr('action');
       }
     }
@@ -688,35 +688,35 @@
    * Sets the progress bar progress indicator.
    */
   Drupal.Ajax.prototype.setProgressIndicatorBar = function () {
-    var progressBar = new Drupal.ProgressBar('ajax-progress-' + this.element.id, $.noop, this.progress.method, $.noop);
+    var progressBar = new Drupal.ProgressBar('ajax-progress-' + $(this.element).id, $.noop, this.progress.method, $.noop);
     if (this.progress.message) {
       progressBar.setProgress(-1, this.progress.message);
     }
     if (this.progress.url) {
       progressBar.startMonitoring(this.progress.url, this.progress.interval || 1500);
     }
-    this.progress.element = $(progressBar.element).addClass('ajax-progress ajax-progress-bar');
+    this.progress.$element = $(progressBar.element).addClass('ajax-progress ajax-progress-bar');
     this.progress.object = progressBar;
-    $(this.element).after(this.progress.element);
+    $(this.element).after(this.progress.$element);
   };
 
   /**
    * Sets the throbber progress indicator.
    */
   Drupal.Ajax.prototype.setProgressIndicatorThrobber = function () {
-    this.progress.element = $('<div class="ajax-progress ajax-progress-throbber"><div class="throbber">&nbsp;</div></div>');
+    this.progress.$element = $('<div class="ajax-progress ajax-progress-throbber"><div class="throbber">&nbsp;</div></div>');
     if (this.progress.message) {
-      this.progress.element.find('.throbber').after('<div class="message">' + this.progress.message + '</div>');
+      this.progress.$element.find('.throbber').after('<div class="message">' + this.progress.message + '</div>');
     }
-    $(this.element).after(this.progress.element);
+    $(this.element).after(this.progress.$element);
   };
 
   /**
    * Sets the fullscreen progress indicator.
    */
   Drupal.Ajax.prototype.setProgressIndicatorFullscreen = function () {
-    this.progress.element = $('<div class="ajax-progress ajax-progress-fullscreen">&nbsp;</div>');
-    $('body').after(this.progress.element);
+    this.progress.$element = $('<div class="ajax-progress ajax-progress-fullscreen">&nbsp;</div>');
+    $('body').after(this.progress.$element);
   };
 
   /**
@@ -727,8 +727,8 @@
    */
   Drupal.Ajax.prototype.success = function (response, status) {
     // Remove the progress element.
-    if (this.progress.element) {
-      $(this.progress.element).remove();
+    if (this.progress.$element) {
+      this.progress.$element.remove();
     }
     if (this.progress.object) {
       this.progress.object.stopMonitoring();
@@ -756,7 +756,7 @@
     // If the focus hasn't be changed by the ajax commands, try to refocus the
     // triggering element or one of its parents if that element does not exist
     // anymore.
-    if (!focusChanged && this.element && !$(this.element).data('disable-refocus')) {
+    if (!focusChanged && $(this.element) && !$(this.element).data('disable-refocus')) {
       var target = false;
 
       for (var n = elementParents.length - 1; !target && n > 0; n--) {
@@ -824,8 +824,8 @@
    */
   Drupal.Ajax.prototype.error = function (xmlhttprequest, uri, customMessage) {
     // Remove the progress element.
-    if (this.progress.element) {
-      $(this.progress.element).remove();
+    if (this.progress.$element) {
+      $(this.progress.$element).remove();
     }
     if (this.progress.object) {
       this.progress.object.stopMonitoring();
diff --git a/core/misc/batch.js b/core/misc/batch.js
index 411badb..d5b6990 100644
--- a/core/misc/batch.js
+++ b/core/misc/batch.js
@@ -38,7 +38,7 @@
         // Remove HTML from no-js progress bar.
         $progress.empty();
         // Append the JS progressbar element.
-        $progress.append(progressBar.element);
+        $progress.append(progressBar.$element);
       }
     }
   };
diff --git a/core/misc/progress.js b/core/misc/progress.js
index 2675751..7d991d0 100644
--- a/core/misc/progress.js
+++ b/core/misc/progress.js
@@ -26,14 +26,14 @@
 
   /**
    * A progressbar object. Initialized with the given id. Must be inserted into
-   * the DOM afterwards through progressBar.element.
+   * the DOM afterwards through progressBar.$element.
    *
    * Method is the function which will perform the HTTP request to get the
    * progress bar state. Either "GET" or "POST".
    *
    * @example
    * pb = new Drupal.ProgressBar('myProgressBar');
-   * some_element.appendChild(pb.element);
+   * some_element.appendChild(pb.$element);
    *
    * @constructor
    *
@@ -52,7 +52,7 @@
     // users
     // have completed their current activity and not interrupt the screen
     // reader.
-    this.element = $(Drupal.theme('progressBar', id));
+    this.$element = $(Drupal.theme('progressBar', id));
   };
 
   $.extend(Drupal.ProgressBar.prototype, /** @lends Drupal.ProgressBar# */{
@@ -66,11 +66,11 @@
      */
     setProgress: function (percentage, message, label) {
       if (percentage >= 0 && percentage <= 100) {
-        $(this.element).find('div.progress__bar').css('width', percentage + '%');
-        $(this.element).find('div.progress__percentage').html(percentage + '%');
+        this.$element.find('div.progress__bar').css('width', percentage + '%');
+        this.$element.find('div.progress__percentage').html(percentage + '%');
       }
-      $('div.progress__description', this.element).html(message);
-      $('div.progress__label', this.element).html(label);
+      $('div.progress__description', this.$element).html(message);
+      $('div.progress__label', this.$element).html(label);
       if (this.updateCallback) {
         this.updateCallback(percentage, message, this);
       }
@@ -147,7 +147,7 @@
      */
     displayError: function (string) {
       var error = $('<div class="messages messages--error"></div>').html(string);
-      $(this.element).before(error).hide();
+      this.$element.before(error).hide();
 
       if (this.errorCallback) {
         this.errorCallback(this);