postoffice-1.0.x-dev/examples/postoffice_form_example/postoffice_form_example.links.task.yml

postoffice.settings:
  title: Settings
  route_name: postoffice.site_settings
  base_route: postoffice.site_settings

postoffice_form_example.mail_test:
  title: Mail Test
  route_name: postoffice_form_example.mail_test
  base_route: postoffice.site_settings