diff --git a/src/Plugin/Field/FieldWidget/OptionsShsWidget.php b/src/Plugin/Field/FieldWidget/OptionsShsWidget.php
index c266874..6f462a1 100644
--- a/src/Plugin/Field/FieldWidget/OptionsShsWidget.php
+++ b/src/Plugin/Field/FieldWidget/OptionsShsWidget.php
@@ -226,7 +226,7 @@ class OptionsShsWidget extends OptionsSelectWidget implements ContainerFactoryPl
 
     // Add support for field_config_cardinality module.
     // @see https://www.drupal.org/project/field_config_cardinality
-    if (\Drupal::moduleHandler()->moduleExists('field_config_cardinality')) {
+    if (\Drupal::moduleHandler()->moduleExists('field_config_cardinality') && $this->fieldDefinition instanceof ThirdPartySettingsInterface) {
       $config_cardinality = (integer) $this->fieldDefinition->getThirdPartySetting('field_config_cardinality', 'cardinality_config');
       $cardinality = $config_cardinality ?: $cardinality;
     }