diff -u b/core/modules/jsonapi/tests/src/Functional/CommentTest.php b/core/modules/jsonapi/tests/src/Functional/CommentTest.php
--- b/core/modules/jsonapi/tests/src/Functional/CommentTest.php
+++ b/core/modules/jsonapi/tests/src/Functional/CommentTest.php
@@ -247,6 +247,9 @@
           'entity_id' => [
             'data' => [
               'type' => 'entity_test--bar',
+              'meta' => [
+                'drupal_internal__target_id' => 1,
+              ],
               'id' => EntityTest::load(1)->uuid(),
             ],
           ],
diff -u b/core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php b/core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php
--- b/core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php
+++ b/core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php
@@ -1820,10 +1820,13 @@
    *   if appropriate.
    */
   protected static function decorateResourceIdentifierWithDrupalInternalTargetId($field, array $resource_identifier): array {
-    $fieldStorageDefinition = $field->getFieldDefinition()
-      ->getFieldStorageDefinition();
-    $property_definition = $fieldStorageDefinition->getPropertyDefinition('target_id');
-    $is_data_reference_definition = $property_definition instanceof DataReferenceTargetDefinition;
+    $property_definitions = $field->getFieldDefinition()->getFieldStorageDefinition()->getPropertyDefinitions();
+
+    if(!isset($property_definitions['target_id'])){
+      return $resource_identifier;
+    }
+
+    $is_data_reference_definition = $property_definitions['target_id'] instanceof DataReferenceTargetDefinition;
     if ($is_data_reference_definition) {
       $resource_identifier['meta']['drupal_internal__target_id'] = is_numeric($field->target_id) ? (int) $field->target_id : $field->target_id;
     }