Tests UI of the embedded entities with untranslatable target types.
public function testTranslatableEntityReferencesUntranslatableTarget() {
// Disable entity translations for entity_test_composite.
\Drupal::service('content_translation.manager')
->setEnabled('entity_test_composite', 'entity_test_composite', FALSE);
// Create the translatable reference field to the composite entity test.
$this
->createEntityReferenceField('node', 'article', 'entity_test_t_composite', 'entity_test_t_composite', 'entity_test_composite');
// Assert there is the entity_test_composite as entity embedded now.
$this
->drupalGet('/admin/tmgmt/settings');
$this
->assertSession()
->fieldExists('embedded_fields[node][entity_test_t_composite]');
$this
->assertSession()
->pageTextContains('Note: This is a translatable field to an untranslatable target. A copy of the target will be created when translating.');
}