toolshed-8.x-1.x-dev/toolshed.links.task.yml

toolshed.js_configs:
  title: 'Settings'
  route_name: toolshed.js_configs
  base_route: toolshed.js_configs

# Configure breakpoints per theme.
toolshed.js_configs.breakpoints:
  title: 'Breakpoints'
  route_name: toolshed.js_configs.breakpoints
  base_route: system.themes_page
  weight: 10

toolshed.js_configs.breakpoints_theme:
  title: 'Breakpoints'
  route_name: toolshed.js_configs.breakpoints_theme
  parent_id: toolshed.js_configs.breakpoints
  deriver: 'Drupal\toolshed\Plugin\Derivative\ThemeDefaultLocalTask'