diff --git a/core/modules/language/src/EventSubscriber/ConfigSubscriber.php b/core/modules/language/src/EventSubscriber/ConfigSubscriber.php
index ef3f65d..8790258 100644
--- a/core/modules/language/src/EventSubscriber/ConfigSubscriber.php
+++ b/core/modules/language/src/EventSubscriber/ConfigSubscriber.php
@@ -57,7 +57,7 @@ public function onConfigSave(ConfigCrudEvent $event) {
     if ($saved_config->getName() == 'system.site' && $event->isChanged('default_langcode')) {
       $language = $this->languageManager->getLanguage($saved_config->get('default_langcode'));
       // During an import the language might not exist yet.
-      if ($language) {
+      if ($language && $language->getId() != $saved_config->getOriginal('default_langcode')) {
         $this->languageDefault->set($language);
         $this->languageManager->reset();
         language_negotiation_url_prefixes_update();