drupal/core/modules/aggregator/aggregator.links.action.yml

aggregator.feed_add:
  route_name: aggregator.feed_add
  title: 'Add feed'
  appears_on:
    - 'aggregator.admin_overview'

aggregator.opml_add:
  route_name: aggregator.opml_add
  title: 'Import OPML'
  appears_on:
    - 'aggregator.admin_overview'