diff --git a/src/wp-includes/class-wp-site.php b/src/wp-includes/class-wp-site.php
index b39d645dbd..4aac6c1030 100644
--- a/src/wp-includes/class-wp-site.php
+++ b/src/wp-includes/class-wp-site.php
@@ -26,6 +26,8 @@ final class WP_Site {
 	 * A numeric string, for compatibility reasons.
 	 *
 	 * @since 4.5.0
+	 * @since 4.6.0 Converted from public to private to explicitly enable more intuitive
+	 *              access via magic methods.
 	 * @access private
 	 * @var string
 	 */
@@ -58,6 +60,8 @@ final class WP_Site {
 	 * A numeric string, for compatibility reasons.
 	 *
 	 * @since 4.5.0
+	 * @since 4.6.0 Converted from public to private to explicitly enable more intuitive
+	 *              access via magic methods.
 	 * @access private
 	 * @var string
 	 */