diff --git a/core/modules/outside_in/src/Tests/Ajax/OffCanvasDialogTest.php b/core/modules/outside_in/src/Tests/Ajax/OffCanvasDialogTest.php
index f351042..3fdf4ba 100644
--- a/core/modules/outside_in/src/Tests/Ajax/OffCanvasDialogTest.php
+++ b/core/modules/outside_in/src/Tests/Ajax/OffCanvasDialogTest.php
@@ -52,7 +52,7 @@ public function testDialog() {
     ];
 
     // Emulate going to the JS version of the page and check the JSON response.
-    $ajax_result = $this->drupalGetAjax('ajax-test/dialog-contents', ['query' => [MainContentViewSubscriber::WRAPPER_FORMAT => 'drupal_dialog_offcanvas']]);
+    $ajax_result = $this->drupalGetAjax('ajax-test/dialog-contents', ['query' => [MainContentViewSubscriber::WRAPPER_FORMAT => 'drupal_dialog.offcanvas']]);
     $this->assertEqual($offcanvas_expected_response, $ajax_result[3], 'Off-canvas dialog JSON response matches.');
   }