Issue #3505514: Undefined array key "#type" in...

Issue #3505514: Undefined array key "#type" in /var/www/app/docroot/modules/contrib/conditional_fields/src/ConditionalFieldsFormHelper.php on line 618

Closes #3505514

src/ConditionalFieldsFormHelper.php

@@ -615,7 +615,8 @@ class ConditionalFieldsFormHelper {
                 }
 
                 if ($element_to_set_error['#access'] ?? TRUE) {
-                  if ($element_to_set_error['#type'] == 'hidden') {
+                  $type = $element_to_set_error['#type'] ?? '';
+                  if ($type == 'hidden') {
                     $element_to_set_error = NestedArray::getValue($form, array_slice($element_to_set_error['#array_parents'], 0, -1));
                     $title = $element_to_set_error['#title'];
                   }