diff --git a/core/modules/system/tests/src/Functional/System/SiteInformationFormTest.php b/core/modules/system/tests/src/Functional/System/SiteInformationFormTest.php
index e5083c9de1..1cdcea8999 100644
--- a/core/modules/system/tests/src/Functional/System/SiteInformationFormTest.php
+++ b/core/modules/system/tests/src/Functional/System/SiteInformationFormTest.php
@@ -33,14 +33,14 @@ public function testSloganSize() {
       'site_slogan' => $this->randomMachineName($slogan_maxlength),
     ];
     $this->drupalPostForm('admin/config/system/site-information', $edit, 'Save configuration');
-    $this->assertSession()->responseContains('The configuration options have been saved.');
+    $this->assertSession()->pageTextContains('The configuration options have been saved.');
 
     $edit = [
       'site_slogan' => $this->randomMachineName($slogan_maxlength + 1),
     ];
     $this->drupalPostForm('admin/config/system/site-information', $edit, 'Save configuration');
-    $expected_error = sprintf('Slogan cannot be longer than <em class="placeholder">%d</em> characters but is currently <em class="placeholder">%d</em> characters long.', $slogan_maxlength, $slogan_maxlength + 1);
-    $this->assertSession()->responseContains($expected_error);
+    $expected_error = sprintf('Slogan cannot be longer than %d characters but is currently %d characters long.', $slogan_maxlength, $slogan_maxlength + 1);
+    $this->assertSession()->pageTextContains($expected_error);
   }
 
 }