\Drupal\options\Plugin\Field\FieldType\ListItemBase

core/modules/options/src/Plugin/Field/FieldType/ListItemBase.php

@@ -83,7 +83,9 @@ public static function generateSampleValue(FieldDefinitionInterface $field_defin
    * {@inheritdoc}
    */
   public function isEmpty() {
-    return empty($this->value) && (string) $this->value !== '0';
+    $value = $this->get('value')->getValue();
+
+    return empty($value) && (string) $value !== '0';
   }
 
   /**

core/phpstan-baseline.neon

@@ -1960,11 +1960,6 @@ parameters:
 			count: 1
 			path: modules/options/src/Plugin/Field/FieldType/ListIntegerItem.php
 
-		-
-			message: "#^Access to an undefined property Drupal\\\\options\\\\Plugin\\\\Field\\\\FieldType\\\\ListItemBase\\:\\:\\$value\\.$#"
-			count: 1
-			path: modules/options/src/Plugin/Field/FieldType/ListItemBase.php
-
 		-
 			message: "#^Method Drupal\\\\options\\\\Plugin\\\\Field\\\\FieldType\\\\ListItemBase\\:\\:validateAllowedValue\\(\\) should return string but return statement is missing\\.$#"
 			count: 1