diff --git a/wp-admin/update-core.php b/wp-admin/update-core.php
index c8196a02b..a586fa211 100644
--- a/wp-admin/update-core.php
+++ b/wp-admin/update-core.php
@@ -129,6 +129,7 @@ function core_upgrade_preamble() {
 
 	list_plugin_updates();
 	//list_theme_updates();
+	do_action('core_upgrade_preamble');
 	echo '</div>';
 }