diff --git a/src/Plugin/Field/FieldWidget/EntityReferenceBrowserWidget.php b/src/Plugin/Field/FieldWidget/EntityReferenceBrowserWidget.php
index 719869c..7b56b02 100644
--- a/src/Plugin/Field/FieldWidget/EntityReferenceBrowserWidget.php
+++ b/src/Plugin/Field/FieldWidget/EntityReferenceBrowserWidget.php
@@ -466,7 +466,7 @@
    * Render API callback: Processes the entity browser element.
    */
   public static function processEntityBrowser(&$element, FormStateInterface $form_state, &$complete_form) {
-    $uuid = key($element['#attached']['drupalSettings']['entity_browser']);
+    $uuid = !empty($element['#attached']['drupalSettings']['entity_browser']) ? key($element['#attached']['drupalSettings']['entity_browser']) : '';
     $element['#attached']['drupalSettings']['entity_browser'][$uuid]['selector'] = '#' . $element['#custom_hidden_id'];
     return $element;
   }