diff --git a/src/wp-includes/script-loader.php b/src/wp-includes/script-loader.php
index 883eadd0e5..ea7f5f4ef7 100644
--- a/src/wp-includes/script-loader.php
+++ b/src/wp-includes/script-loader.php
@@ -537,6 +537,7 @@ function wp_default_scripts( &$scripts ) {
 				'updatingMsg'       => __( 'Updating... please wait.' ),
 				'updatedMsg'        => __( 'Update completed successfully.' ),
 				'updateCancel'      => __( 'Update canceled.' ),
+				'beforeunload'      => __( 'Plugin updates may not complete if you navigate away from this page.' ),
 			)
 		) );