diff --git a/core/includes/theme.inc b/core/includes/theme.inc
index 65f3839..b510e54 100644
--- a/core/includes/theme.inc
+++ b/core/includes/theme.inc
@@ -1506,10 +1506,12 @@ function template_preprocess_field(&$variables, $hook) {
   // readers.
   $variables['label'] = SafeMarkup::checkPlain($element['#title']);
 
-  // Check if there are multiple field items.
   $variables['multiple'] = FALSE;
-  if (isset($element['#items']) && is_callable($element['#items'], 'getFieldDefinition') && is_callable($element['#items']->getFieldDefinition(), 'isMultiple')) {
-    $variables['multiple'] = $element['items']->getFieldDefinition()->isMultiple();
+  if (isset($element['#items']) && method_exists($element['#items'], 'getFieldDefinition')) {
+    $fieldDefinition = $element['#items']->getFieldDefinition();
+    if (method_exists($fieldDefinition, 'getFieldStorageDefinition')) {
+      $variables['multiple'] = $fieldDefinition->getFieldStorageDefinition()->isMultiple();
+    }
   }
 
   static $default_attributes;