diff --git a/src/Plugin/facets/processor/TermWeightWidgetOrderProcessor.php b/src/Plugin/facets/processor/TermWeightWidgetOrderProcessor.php
index 7732370..c69c03a 100644
--- a/src/Plugin/facets/processor/TermWeightWidgetOrderProcessor.php
+++ b/src/Plugin/facets/processor/TermWeightWidgetOrderProcessor.php
@@ -4,6 +4,7 @@
 
 use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\TypedData\ComplexDataDefinitionInterface;
 use Drupal\Core\TypedData\DataReferenceDefinitionInterface;
 use Drupal\facets\FacetInterface;
 use Drupal\facets\Processor\SortProcessorPluginBase;
@@ -92,6 +93,14 @@ public function sortResults(Result $a, Result $b) {
    * {@inheritdoc}
    */
   public function supportsFacet(FacetInterface $facet) {
+    $data_definition = $facet->getDataDefinition();
+    if ($data_definition->getDataType() === 'entity_reference') {
+      return TRUE;
+    }
+    if (!($data_definition instanceof ComplexDataDefinitionInterface)) {
+      return FALSE;
+    }
+
     $data_definition = $facet->getDataDefinition();
     $property_definitions = $data_definition->getPropertyDefinitions();
     foreach ($property_definitions as $definition) {
diff --git a/tests/src/Functional/ProcessorIntegrationTest.php b/tests/src/Functional/ProcessorIntegrationTest.php
index 5e9df76..23dbc92 100644
--- a/tests/src/Functional/ProcessorIntegrationTest.php
+++ b/tests/src/Functional/ProcessorIntegrationTest.php
@@ -740,7 +740,12 @@ public function testProcessorConfig() {
       }
       // These processors are hidden by default, see also
       // ::testHiddenProcessors.
-      if (in_array($processor->getPluginId(), ['boolean_item', 'translate_entity', 'uid_to_username_callback'])) {
+      $hiddenProcessors = [
+        'boolean_item',
+        'translate_entity',
+        'uid_to_username_callback',
+      ];
+      if (in_array($processor->getPluginId(), $hiddenProcessors)) {
         continue;
       }