--- /dev/null
+<?php
+
+namespace Drupal\config_translation_test\EventSubscriber;
+
+use Drupal\config_translation\Event\ConfigMapperPopulateEvent;
+use Drupal\config_translation\Event\ConfigTranslationEvents;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+
+/**
+ * Adds configuration names to configuration mapper on POPULATE_MAPPER event.
+ */
+class ConfigTranslationTestSubscriber implements EventSubscriberInterface {
+
+ /**
+ * {@inheritdoc}
+ */
+ public static function getSubscribedEvents() {
+ return [
+ ConfigTranslationEvents::POPULATE_MAPPER => [
+ ['addConfigNames'],
+ ],
+ ];
+ }
+
+ /**
+ * Reacts to the populating of a configuration mapper.
+ *
+ * @param \Drupal\config_translation\Event\ConfigMapperPopulateEvent $event
+ * The configuration mapper event.
+ */
+ public function addConfigNames(ConfigMapperPopulateEvent $event) {
+ $mapper = $event->getMapper();
+ if ($mapper->getBaseRouteName() === 'system.site_information_settings' && $mapper->getLangcode() === 'en') {
+ $mapper->addConfigName('config_translation_test.content');
+ }
+ }
+
+}