diff --git a/core/lib/Drupal/Core/Database/Install/Tasks.php b/core/lib/Drupal/Core/Database/Install/Tasks.php
index 024bf5a..98b7059 100644
--- a/core/lib/Drupal/Core/Database/Install/Tasks.php
+++ b/core/lib/Drupal/Core/Database/Install/Tasks.php
@@ -8,7 +8,6 @@
 namespace Drupal\Core\Database\Install;
 
 use Drupal\Component\Utility\SafeMarkup;
-use Drupal\Component\Utility\String;
 use Drupal\Core\Database\Database;
 
 /**
@@ -152,7 +151,7 @@ public function runTasks() {
     $message = '';
     foreach ($this->results as $result => $success) {
       if (!$success) {
-        $message = SafeMarkup::isSafe($result) ? $result : String::checkPlain($result);
+        $message .= SafeMarkup::escape($result);
       }
     }
     if (!empty($message)) {