diff --git a/core/modules/system/lib/Drupal/system/Tests/System/SystemConfigFormBase.php b/core/modules/system/lib/Drupal/system/Tests/System/SystemConfigFormBase.php
index 867bb10..61301d2 100644
--- a/core/modules/system/lib/Drupal/system/Tests/System/SystemConfigFormBase.php
+++ b/core/modules/system/lib/Drupal/system/Tests/System/SystemConfigFormBase.php
@@ -49,8 +49,6 @@ abstract class SystemConfigFormBase extends WebTestBase {
     $this->setUpSystemConfigForm();
   }
 
-  abstract function setUpSystemConfigForm();
-
   /**
    * Submit the system_config_form ensure the configuration has expected values.
    */