examples-3.x-dev/modules/js_example/js_example.links.menu.yml

# Define default links for this module.
js_example.info:
  title: JavaScript Example
  description: Some information about JavaScript Example.
  route_name: js_example.info
  expanded: TRUE

js_example.colors:
  title: JavaScript weighting in action
  description: Show list weighting through JavaScript.
  route_name: js_example.colors
  parent: js_example.info
  weight: 10

js_example.accordion:
  title: JavaScript accordion
  description: A pure JavaScript accordion demo
  route_name: js_example.accordion
  parent: js_example.info
  weight: 1