Issue #3202244: TypeError: Argument 1 passed to Drupal\default_content\Normalizer\ContentEntityNormalizer::addDependency() must implement interface Drupal\Core\Entity\ContentEntityInterface, null given

src/Normalizer/ContentEntityNormalizer.php

@@ -121,7 +121,9 @@ class ContentEntityNormalizer implements ContentEntityNormalizerInterface {
       if (strpos($entity->getParentId(), PluginBase::DERIVATIVE_SEPARATOR) !== FALSE) {
         [$plugin_id, $parent_uuid] = explode(PluginBase::DERIVATIVE_SEPARATOR, $entity->getParentId());
         if ($plugin_id === 'menu_link_content' && $parent_entity = $this->entityRepository->loadEntityByUuid('menu_link_content', $parent_uuid)) {
-          $this->addDependency($parent_entity);
+          if ($parent_entity instanceof ContentEntityInterface) {
+            $this->addDependency($parent_entity);
+          }
         }
       }
     }
@@ -415,8 +417,10 @@ class ContentEntityNormalizer implements ContentEntityNormalizerInterface {
         $value = $this->normalize($target);
       }
       else {
-        $this->addDependency($target);
-        $value = $target->uuid();
+        if ($parent_entity instanceof ContentEntityInterface) {
+          $this->addDependency($parent_entity);
+          $value = $target->uuid();
+        }
       }
     }
     elseif ($property instanceof Uri) {
@@ -427,8 +431,10 @@ class ContentEntityNormalizer implements ContentEntityNormalizerInterface {
         $path = parse_url($value, PHP_URL_PATH);
         [$target_entity_type_id, $target_id] = explode('/', $path);
         $target = $this->entityTypeManager->getStorage($target_entity_type_id)->load($target_id);
-        $this->addDependency($target);
-        $normalized_item['target_uuid'] = $target->uuid();
+        if ($target instanceof ContentEntityInterface) {
+          $this->addDependency($target);
+          $normalized_item['target_uuid'] = $target->uuid();
+        }
         $value = NULL;
       }
     }