display_builder-1.0.x-dev/modules/display_builder_entity_view/display_builder_entity_view.routing.yml

display_builder_entity_view.save_form:
  path: '/api/display-builder/_/entity_view_display'
  defaults:
    _form: '\Drupal\display_builder_entity_view\Form\DisplayBuilderEntityViewDisplaySaveForm'
    _title: ''
  methods: [POST]
  requirements:
    _permission: 'administer display builders'