diff --git a/wp-includes/script-loader.php b/wp-includes/script-loader.php
index f9813ed87c..7c960a2d91 100644
--- a/wp-includes/script-loader.php
+++ b/wp-includes/script-loader.php
@@ -144,7 +144,7 @@ function wp_default_packages_vendor( $scripts ) {
 		'moment',
 		sprintf(
 			"moment.updateLocale( '%s', %s );",
-			get_user_locale(),
+			esc_js( get_user_locale() ),
 			wp_json_encode(
 				array(
 					'months'         => array_values( $wp_locale->month ),
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 273ddf66ca..2ad8afcfab 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.6-alpha-58287';
+$wp_version = '6.6-alpha-58288';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.