diff --git a/core/modules/system/system.post_update.php b/core/modules/system/system.post_update.php
index dbcce04..193a14e 100644
--- a/core/modules/system/system.post_update.php
+++ b/core/modules/system/system.post_update.php
@@ -65,11 +65,3 @@ function system_post_update_add_region_to_entity_displays() {
 function system_post_update_clear_twig_cache() {
   // Empty post-update hook.
 }
-
-/**
- * Add the workflow entity type.
- */
-function system_post_update_add_workflow_entity_type() {
-  $workflow_type = \Drupal::entityManager()->getDefinition('workflow');
-  \Drupal::entityDefinitionUpdateManager()->installEntityType($workflow_type);
-}