diff --git a/src/wp-admin/includes/class-wp-upgrader-skins.php b/src/wp-admin/includes/class-wp-upgrader-skins.php
index 6f34022069..42488d9a93 100644
--- a/src/wp-admin/includes/class-wp-upgrader-skins.php
+++ b/src/wp-admin/includes/class-wp-upgrader-skins.php
@@ -137,6 +137,9 @@ class WP_Upgrader_Skin {
 				</script>';
 		}
 	}
+
+	public function bulk_header() {}
+	public function bulk_footer() {}
 }
 
 /**