--- /dev/null
+/**
+ * Implements hook_ENTITY_TYPE_revision_create().
+ */
+function {{ machine_name }}_ENTITY_TYPE_revision_create(Drupal\Core\Entity\EntityInterface $new_revision, Drupal\Core\Entity\EntityInterface $entity, $keep_untranslatable_fields) {
+ // Retain the value from an untranslatable field, which are by default
+ // synchronized from the default revision.
+ $new_revision->set('untranslatable_field', $entity->get('untranslatable_field'));
+}