diff --git a/core/modules/book/book.js b/core/modules/book/book.js
index b7a6713..6ffc91f 100644
--- a/core/modules/book/book.js
+++ b/core/modules/book/book.js
@@ -5,7 +5,7 @@
 Drupal.behaviors.bookFieldsetSummaries = {
   attach: function (context) {
     $(context).find('fieldset.book-outline-form').drupalSetSummary(function (context) {
-      var $select = $('.form-item-book-bid select');
+      var $select = $(context).find('.form-item-book-bid select');
       var val = $select.val();
 
       if (val === '0') {