diff --git a/wp-includes/version.php b/wp-includes/version.php
index 76d1bf3257..c61b1c97f1 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-39891';
+$wp_version = '4.8-alpha-39892';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.
diff --git a/wp-includes/widgets.php b/wp-includes/widgets.php
index 30c1fce53d..1abadfb186 100644
--- a/wp-includes/widgets.php
+++ b/wp-includes/widgets.php
@@ -281,12 +281,12 @@ function register_sidebar($args = array()) {
  *
  * @global array $wp_registered_sidebars Stores the new sidebar in this array by sidebar ID.
  *
- * @param string $name The ID of the sidebar when it was added.
+ * @param string|int $sidebar_id The ID of the sidebar when it was registered.
  */
-function unregister_sidebar( $name ) {
+function unregister_sidebar( $sidebar_id ) {
 	global $wp_registered_sidebars;
 
-	unset( $wp_registered_sidebars[ $name ] );
+	unset( $wp_registered_sidebars[ $sidebar_id ] );
 }
 
 /**