diff --git a/wp-includes/class-wp-customize-widgets.php b/wp-includes/class-wp-customize-widgets.php
index e5e5445118..feaade3812 100644
--- a/wp-includes/class-wp-customize-widgets.php
+++ b/wp-includes/class-wp-customize-widgets.php
@@ -1738,7 +1738,7 @@ final class WP_Customize_Widgets {
 	 * The current request's sidebar_instance_number context.
 	 *
 	 * @since 4.5.0
-	 * @var int
+	 * @var int|null
 	 */
 	protected $context_sidebar_instance_number;
 
@@ -1790,7 +1790,7 @@ final class WP_Customize_Widgets {
 	 * Current sidebar being rendered.
 	 *
 	 * @since 4.5.0
-	 * @var string
+	 * @var string|null
 	 */
 	protected $rendering_widget_id;
 
@@ -1798,7 +1798,7 @@ final class WP_Customize_Widgets {
 	 * Current widget being rendered.
 	 *
 	 * @since 4.5.0
-	 * @var string
+	 * @var string|null
 	 */
 	protected $rendering_sidebar_id;
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 1caa576403..0f0d112db4 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.3-alpha-45428';
+$wp_version = '5.3-alpha-45429';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.