diff --git a/src/Element/MediaLibrary.php b/src/Element/MediaLibrary.php
index 6e133b4..5a73f3e 100644
--- a/src/Element/MediaLibrary.php
+++ b/src/Element/MediaLibrary.php
@@ -62,7 +62,9 @@ class MediaLibrary extends FormElement {
       $entity_ids = [$default_value['media_selection_id']];
     }
     else {
-      $entity_ids = array_filter(explode(',', $default_value ?? ''));
+      if (is_string($default_value)) {
+        $entity_ids = array_filter(explode(',', $default_value ?: ''));
+      }
     }
 
     if (!empty($entity_ids)) {