Index: src/wp-login.php
===================================================================
--- src/wp-login.php	(revision 51604)
+++ src/wp-login.php	(working copy)
@@ -983,10 +983,11 @@
 		 * Filters the registration redirect URL.
 		 *
 		 * @since 3.0.0
-		 *
+		 * @since 5.9.0 Added the `$errors` parameter.
 		 * @param string $registration_redirect The redirect destination URL.
+		 * @param int|WP_Error $error   User id if registration was successful, WP_Error object otherwise.
 		 */
-		$redirect_to = apply_filters( 'registration_redirect', $registration_redirect );
+		$redirect_to = apply_filters( 'registration_redirect', $registration_redirect, $errors );
 
 		login_header( __( 'Registration Form' ), '<p class="message register">' . __( 'Register For This Site' ) . '</p>', $errors );