Drupal 8 System Link Menu

system.admin:
  title: Administration
  route_name: system.admin
  weight: 9
  menu_name: admin
system.admin_content:
  title: Content
  description: 'Find and manage content.'
  route_name: system.admin_content
  parent: system.admin
  weight: -10
system.admin_structure:
  route_name: system.admin_structure
  parent: system.admin
  description: 'Administer blocks, content types, menus, etc.'
  title: Structure
  weight: -8
system.themes_page:
  route_name: system.themes_page
  title: Appearance
  description: 'Select and configure themes.'
  parent: system.admin
  weight: -6
system.modules_list:
  title: Extend
  description: 'Add and enable modules to extend site functionality.'
  parent: system.admin
  route_name: system.modules_list
  weight: -2
system.admin_config:
  title: Configuration
  parent: system.admin
  description: 'Administer settings.'
  route_name: system.admin_config
  weight: 0
system.admin_config_media:
  route_name: system.admin_config_media
  parent: system.admin_config
  title: Media
  weight: -10
system.file_system_settings:
  title: 'File system'
  description: 'Configure the location of uploaded files and how they are accessed.'
  parent: system.admin_config_media
  route_name: system.file_system_settings
system.image_toolkit_settings:
  title: 'Image toolkit'
  parent: system.admin_config_media
  route_name: system.image_toolkit_settings
  description: 'Choose which image toolkit to use if you have installed optional toolkits.'
  weight: 20
system.admin_config_services:
  title: 'Web services'
  parent: system.admin_config
  route_name: system.admin_config_services
system.rss_feeds_settings:
  title: 'RSS publishing'
  parent: system.admin_config_services
  description: 'Configure the site description, the number of items per feed, and whether feeds should be titles/teasers/full-text.'
  route_name: system.rss_feeds_settings
system.admin_config_development:
  route_name: system.admin_config_development
  parent: system.admin_config
  title: Development
  description: 'Configure and use development tools.'
  weight: -10
system.site_maintenance_mode:
  title: 'Maintenance mode'
  parent: system.admin_config_development
  description: 'Take the site offline for updates and other maintenance tasks.'
  route_name: system.site_maintenance_mode
  weight: -10
system.performance_settings:
  title: Performance
  parent: system.admin_config_development
  description: 'Configure caching and bandwidth optimization.'
  route_name: system.performance_settings
  weight: -20
system.logging_settings:
  title: 'Logging and errors'
  parent: system.admin_config_development
  description: 'Configure the display of error messages and database logging.'
  route_name: system.logging_settings
  weight: -15
system.admin_config_regional:
  route_name: system.admin_config_regional
  title: 'Regional and language'
  parent: system.admin_config
  description: 'Configure regional settings, localization, and translation.'
  weight: -5
system.regional_settings:
  title: 'Regional settings'
  parent: system.admin_config_regional
  description: 'Configure the locale and timezone settings.'
  route_name: system.regional_settings
  weight: -20
entity.date_format.collection:
  title: 'Date and time formats'
  parent: system.admin_config_regional
  description: 'Configure how dates and times are displayed.'
  route_name: entity.date_format.collection
  weight: -9
system.admin_config_search:
  title: 'Search and metadata'
  route_name: system.admin_config_search
  parent: system.admin_config
  description: 'Configure site search, metadata, and search engine optimization.'
  weight: -10
system.admin_config_system:
  title: System
  route_name: system.admin_config_system
  parent: system.admin_config
  description: 'Configure basic site settings, actions, and cron.'
  weight: -20
system.site_information_settings:
  title: 'Basic site settings'
  parent: system.admin_config_system
  description: 'Change site name, email address, slogan, default front page, and error pages.'
  route_name: system.site_information_settings
  weight: -20
system.cron_settings:
  title: Cron
  parent: system.admin_config_system
  description: 'Manage automatic site maintenance tasks.'
  route_name: system.cron_settings
  weight: 20
system.admin_config_ui:
  title: 'User interface'
  route_name: system.admin_config_ui
  parent: system.admin_config
  description: 'Configure the administrative user interface.'
  weight: -15
system.admin_config_workflow:
  title: Workflow
  route_name: system.admin_config_workflow
  parent: system.admin_config
  description: 'Manage the content workflow.'
  weight: 5
system.admin_config_content:
  title: 'Content authoring'
  route_name: system.admin_config_content
  parent: system.admin_config
  description: 'Configure content formatting and authoring.'
  weight: -15
system.admin_reports:
  title: Reports
  route_name: system.admin_reports
  parent: system.admin
  description: 'View reports, updates, and errors.'
  weight: 5
system.status:
  title: 'Status report'
  parent: system.admin_reports
  description: 'Get a status report about your site''s operation.'
  route_name: system.status