diff --git a/core/misc/message.es6.js b/core/misc/message.es6.js
index a69708018e..dab7b82d22 100644
--- a/core/misc/message.es6.js
+++ b/core/misc/message.es6.js
@@ -38,7 +38,7 @@
       if (!wrapper) {
         throw new Error(Drupal.t('There is no @element on the page.', { '@element': '[data-drupal-messages]' }));
       }
-      return wrapper.innerHTML === '' ? Drupal.theme('createMessageInternalWrapper', wrapper) : wrapper.firstElementChild;
+      return wrapper.innerHTML === '' ? Drupal.theme('messageInternalWrapper', wrapper) : wrapper.firstElementChild;
     }
 
     /**
@@ -258,7 +258,7 @@
    * @return {HTMLElement}
    *   The internal wrapper DOM element.
    */
-  Drupal.theme.createMessageInternalWrapper = (messageWrapper) => {
+  Drupal.theme.messageInternalWrapper = (messageWrapper) => {
     const innerWrapper = document.createElement('div');
     innerWrapper.setAttribute('class', 'messages__wrapper');
     messageWrapper.insertAdjacentElement('afterbegin', innerWrapper);
diff --git a/core/misc/message.js b/core/misc/message.js
index e1c41c19d7..ee804ec991 100644
--- a/core/misc/message.js
+++ b/core/misc/message.js
@@ -84,7 +84,7 @@ function _classCallCheck(instance, Constructor) { if (!(instance instanceof Cons
         if (!wrapper) {
           throw new Error(Drupal.t('There is no @element on the page.', { '@element': '[data-drupal-messages]' }));
         }
-        return wrapper.innerHTML === '' ? Drupal.theme('createMessageInternalWrapper', wrapper) : wrapper.firstElementChild;
+        return wrapper.innerHTML === '' ? Drupal.theme('messageInternalWrapper', wrapper) : wrapper.firstElementChild;
       }
     }, {
       key: 'getMessageTypes',
@@ -137,7 +137,7 @@ function _classCallCheck(instance, Constructor) { if (!(instance instanceof Cons
     return messageWraper;
   };
 
-  Drupal.theme.createMessageInternalWrapper = function (messageWrapper) {
+  Drupal.theme.messageInternalWrapper = function (messageWrapper) {
     var innerWrapper = document.createElement('div');
     innerWrapper.setAttribute('class', 'messages__wrapper');
     messageWrapper.insertAdjacentElement('afterbegin', innerWrapper);