o365-2.0.3/modules/o365_outlook_mail/o365_outlook_mail.routing.yml

o365_outlook_mail.my_mail_controller_getMail:
  path: 'my-latest-mail'
  defaults:
    _controller: '\Drupal\o365_outlook_mail\Controller\MyMailController::getMail'
    _title: 'My latest mail'
  requirements:
    _permission: 'access o365_outlook_mail page'