diff --git a/core/modules/system/system.module b/core/modules/system/system.module
index 17015c6276074cecd6360245bcf92c9bd5d4adcd..106ef14f176b343bf1dcc8803f30e2b71b51d886 100644
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -2560,7 +2560,6 @@ function system_form_user_profile_form_alter(&$form, &$form_state) {
   if (config('system.timezone')->get('user.configurable')) {
     system_user_timezone($form, $form_state);
   }
-  return $form;
 }
 
 /**
@@ -2570,7 +2569,6 @@ function system_form_user_register_form_alter(&$form, &$form_state) {
   $config = config('system.timezone');
   if ($config->get('user.configurable') && $config->get('user.default') == DRUPAL_USER_TIMEZONE_SELECT) {
     system_user_timezone($form, $form_state);
-    return $form;
   }
 }