diff --git a/lib/behat/classes/partial_named_selector.php b/lib/behat/classes/partial_named_selector.php
index 86830de043d..2e5b450147a 100644
--- a/lib/behat/classes/partial_named_selector.php
+++ b/lib/behat/classes/partial_named_selector.php
@@ -159,7 +159,7 @@ XPATH
 .//div[
         contains(concat(' ', normalize-space(@class), ' '), ' modal ')
             and
-        normalize-space(descendant::*[contains(concat(' ', normalize-space(@class), ' '), ' modal-header ')] = %locator%)
+        normalize-space(descendant::*[contains(concat(' ', normalize-space(@class), ' '), ' modal-header ')]) = %locator%
     ]
 XPATH
         , 'group_message' => <<<XPATH