https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Display%21Annotation%21PageDisplayVariant.php/class/PageDisplayVariant/10
class PageDisplayVariant | Drupal API
classdrupalapi
https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Display%21Attribute%21PageDisplayVariant.php/10
PageDisplayVariant.php | Drupal API
phpdrupalapi
https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Display%21Annotation%21PageDisplayVariant.php/8.9.x
PageDisplayVariant.php | Drupal API
phpdrupalapi