Add system update 20 which corrects an issue in the DB where some original/core system pages had an incorrect (though inconsequential) created_users_id that referred to the admin page rather than the original admin user.

wire/modules/System/SystemUpdater/SystemUpdate20.php

@@ -0,0 +1,29 @@
+<?php namespace ProcessWire;
+
+/**
+ * Correct created_users_id on some pages from admin page ID to be default superuser ID
+ *
+ */
+class SystemUpdate20 extends SystemUpdate {
+	public function execute() {
+		$this->wire()->addHookAfter('ProcessWire::ready', $this, 'executeAtReady');
+		return 0; // indicates we will update system version ourselves when ready
+	}
+	public function executeAtReady() {
+		$database = $this->wire()->database;
+		$config = $this->wire()->config;
+		/** @var User $u */
+		$u = $this->wire()->users->get($config->superUserPageID); 
+		$superuserId = $u->id && $u->isSuperuser() ? $u->id : 0;
+		$sql = 'UPDATE pages SET created_users_id=:superuser_id WHERE created_users_id=:admin_page_id';
+		$query = $database->prepare($sql);
+		$query->bindValue(':superuser_id', $superuserId, \PDO::PARAM_INT);
+		$query->bindValue(':admin_page_id', $config->adminRootPageID, \PDO::PARAM_INT);
+		$query->execute();
+		$rowCount = $query->rowCount();
+		if($rowCount) $this->message("Updated $rowCount page(s) for correct created_users_id");
+		$this->updater->saveSystemVersion(20);
+	}
+}
+
+

wire/modules/System/SystemUpdater/SystemUpdater.module

@@ -26,7 +26,7 @@ class SystemUpdater extends WireData implements Module, ConfigurableModule {
 			 * This version number is important, as this updater keeps the systemVersion up with this version
 			 *
 			 */
-			'version' => 19, 
+			'version' => 20, 
 		);
 	}