$data['node_field_revision']['nid']['relationship']['base field'] = 'nid';
$data['node_field_revision']['nid']['relationship']['title'] = $this->t('Content');
$data['node_field_revision']['nid']['relationship']['label'] = $this->t('Get the actual content from a content revision.');
+ $data['node_field_revision']['nid']['relationship']['extra'][] = [
+ 'field' => 'langcode',
+ 'left_field' => 'langcode',
+ ];
$data['node_field_revision']['vid'] = [
'argument' => [
'base field' => 'vid',
'title' => $this->t('Content'),
'label' => $this->t('Get the actual content from a content revision.'),
+ 'extra' => [
+ [
+ 'field' => 'langcode',
+ 'left_field' => 'langcode',
+ ],
+ ],
],
] + $data['node_field_revision']['vid'];