diff --git a/core/lib/Drupal/Core/Config/Entity/DraggableListBuilder.php b/core/lib/Drupal/Core/Config/Entity/DraggableListBuilder.php
index 08a71ed..73774ed 100644
--- a/core/lib/Drupal/Core/Config/Entity/DraggableListBuilder.php
+++ b/core/lib/Drupal/Core/Config/Entity/DraggableListBuilder.php
@@ -42,9 +42,9 @@
   /**
    * HTML class to identify the weight input elements.
    *
-   * @var string
+   * @var string|bool
    */
-  protected $weightClass = 'weight';
+  protected $weightClass = FALSE;
 
   /**
    * The form builder.
@@ -62,6 +62,7 @@ public function __construct(EntityTypeInterface $entity_type, EntityStorageInter
     // Check if the entity type supports weighting.
     if ($this->entityType->hasKey('weight')) {
       $this->weightKey = $this->entityType->getKey('weight');
+      $this->weightClass = \Drupal\Component\Utility\Html::getClass($this->weightKey);
     }
   }