Issue #3316974: PriceItem field type does not filter available currencies stored in config.

modules/price/src/Plugin/Field/FieldType/PriceItem.php

@@ -127,6 +127,16 @@ class PriceItem extends FieldItemBase {
     return $element;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public static function fieldSettingsToConfigData(array $settings) {
+    $settings['available_currencies'] = array_filter(
+      $settings['available_currencies']
+    );
+    return $settings;
+  }
+
   /**
    * {@inheritdoc}
    */