pm-4.1.x-dev/modules/pm_epic/pm_epic.links.action.yml

pm_epic.type_add:
  title: 'Add Epic type'
  route_name: entity.pm_epic_type.add_form
  appears_on:
    - entity.pm_epic_type.collection

pm_epic.add_page:
  title: 'Add Epic'
  route_name: entity.pm_epic.add_page
  appears_on:
    - entity.pm_epic.collection
    - view.pm_epic.collection
    - entity.pm_project.canonical