diff --git a/src/wp-includes/class-wp-customize-manager.php b/src/wp-includes/class-wp-customize-manager.php
index 296e8af9be..d4e53911c4 100644
--- a/src/wp-includes/class-wp-customize-manager.php
+++ b/src/wp-includes/class-wp-customize-manager.php
@@ -232,7 +232,7 @@ final class WP_Customize_Manager {
 	 * Changeset data loaded from a customize_changeset post.
 	 *
 	 * @since 4.7.0
-	 * @var array
+	 * @var array|null
 	 */
 	private $_changeset_data;