reverted:
--- b/src/Plugin/Field/FieldWidget/TablefieldWidget.php
+++ a/src/Plugin/Field/FieldWidget/TablefieldWidget.php
@@ -204,23 +204,6 @@
     }
   }
 
-  /**
-   * {@inheritDoc}
-   */
-  public function massageFormValues(array $values, array $form, FormStateInterface $form_state) {
-    if ($values) {
-      foreach ($values as &$value) {
-        $rows = &$value['value']['tablefield']['table'];
-        usort($rows, ['Drupal\Component\Utility\SortArray', 'sortByWeightElement']);
-        foreach ($rows as &$row) {
-          unset($row['weight']);
-        }
-      }
-    }
-
-    return parent::massageFormValues($values, $form, $form_state);
-  }
-
   /**
    * {@inheritdoc}
    *