diff --git a/src/Element/EntityBrowserElement.php b/src/Element/EntityBrowserElement.php
index 206d247..1c15de0 100644
--- a/src/Element/EntityBrowserElement.php
+++ b/src/Element/EntityBrowserElement.php
@@ -3,6 +3,7 @@
 namespace Drupal\entity_browser\Element;
 
 use Drupal\Component\Utility\Html;
+use Drupal\Core\Entity\EntityFormInterface;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Render\Element\FormElement;
 use Drupal\entity_browser\Entity\EntityBrowser;
@@ -141,11 +142,12 @@ class EntityBrowserElement extends FormElement {
       $entity_browser = $element['#entity_browser'];
     }
 
-    // Propagate the field cardinality to the EntityBrowser element.
-    /** @var EntityInterface $entity */
-    $entity = $form_state->getFormObject()->getEntity();
-    $bundle = $form_state->get(['form_display'])->get('bundle');
-    if ($entity && $bundle) {
+    // Propagate the field cardinality to the EntityBrowser element, if needed.
+    $form_object = $form_state->getFormObject();
+    if ($form_object instanceof EntityFormInterface) {
+      /** @var EntityInterface $entity */
+      $entity = $form_state->getFormObject()->getEntity();
+      $bundle = $form_state->get(['form_display'])->get('bundle');
       $field_name = $element['#parents'][0];
       $bundle_fields = \Drupal::getContainer()->get('entity_field.manager')->getFieldDefinitions($entity->getEntityTypeId(), $bundle);
       /** @var \Drupal\field\FieldConfigInterface $instance */