diff --git a/lib/adminlib.php b/lib/adminlib.php
index 135538fa233..156aa5440f2 100644
--- a/lib/adminlib.php
+++ b/lib/adminlib.php
@@ -111,6 +111,11 @@ require_once($CFG->libdir.'/ddllib.php');
 require_once($CFG->libdir.'/xmlize.php');
 require_once($CFG->libdir.'/messagelib.php');
 
+// Add classes, traits, and interfaces which should be autoloaded.
+// The autoloader is configured late in setup.php, after ABORT_AFTER_CONFIG.
+// This is also required where the setup system is not included at all.
+require_once($CFG->dirroot.'/admin/classes/local/settings/linkable_settings_page.php');
+
 define('INSECURE_DATAROOT_WARNING', 1);
 define('INSECURE_DATAROOT_ERROR', 2);