drupal/core/modules/system/config/schema/system.schema.yml

# Schema for the configuration files of the System module.

system.site:
  type: mapping
  label: 'Site information'
  mapping:
    name:
      type: label
      label: 'Site name'
    mail:
      type: email
      label: 'E-mail address'
    slogan:
      type: label
      label: 'Slogan'
    page:
      type: mapping
      label: 'Pages'
      mapping:
        403:
          type: path
          label: 'Default 403 (access denied) page'
        404:
          type: path
          label: 'Default 404 (not found) page'
        front:
          type: path
          label: 'Default front page'
    admin_compact_mode:
      type: boolean
      label: 'Compact mode'
    weight_select_max:
      type: integer
      label: 'Weight element maximum value'
    langcode:
      type: string
      label: 'Default language'

system.maintenance:
  type: mapping
  label: 'Maintenance mode'
  mapping:
    enabled:
      type: boolean
      label: 'Put site into maintenance mode'
    message:
      type: text
      label: 'Message to display when in maintenance mode'
    langcode:
      type: string
      label: 'Default language'

system.authorize:
  type: mapping
  label: 'Authorize settings'
  mapping:
    filetransfer_default:
      type: string
      label: 'Default file transfer protocol'

system.cron:
  type: mapping
  label: 'Cron settings'
  mapping:
    threshold:
      type: mapping
      label: 'Thresholds'
      mapping:
        autorun:
          type: integer
          label: 'Run cron every'
        requirements_warning:
          type: integer
          label: 'Requirements warning period'
        requirements_error:
          type: integer
          label: 'Requirements error period'

system.date:
  type: mapping
  label: 'Date settings'
  mapping:
    first_day:
      type: integer
      label: 'First day of week'
    country:
      type: mapping
      label: 'Country'
      mapping:
        default:
          type: string
          label: 'Default country'
    langcode:
      type: string
      label: 'Default language'

system.date_format.*:
  type: mapping
  label: 'Date format'
  mapping:
    id:
      type: string
      label: 'Date format identifier'
    uuid:
      type: string
      label: 'UUID'
    label:
      type: label
      label: 'Date format label'
    status:
      type: boolean
      label: 'Enabled'
    locked:
      type: boolean
      label: 'Locked'
    locales:
      type: sequence
      label: 'Languages'
      sequence:
        - type: string
          label: 'Language'
    pattern:
      type: mapping
      label: 'Format string'
      mapping:
        php:
          type: string
          label: 'PHP date format'
        intl:
          type: string
          label: 'Intl date format'
    langcode:
      type: string
      label: 'Default language'

system.fast_404:
  type: mapping
  label: 'Fast 404 settings'
  mapping:
    enabled:
      type: boolean
      label: 'Enabled'
    paths:
      type: string
      label: 'Paths'
    exclude_paths:
      type: string
      label: 'Exclude paths'
    html:
      type: string
      label: 'HTML'

system.filter:
  type: mapping
  label: 'Filter settings'
  mapping:
    protocols:
      type: sequence
      label: 'Allowed protocols'
      sequence:
        - type: string
          label: 'Protocol'

system.language.types:
  type: mapping
  label: 'Language types'
  mapping:
    all:
      type: sequence
      label: 'All language types'
      sequence:
        - type: string
          label: 'Language type'
    configurable:
      type: sequence
      label: 'Configurable language types'
      sequence:
        - type: string
          label: 'Language type'

system.logging:
  type: mapping
  label: 'Logging settings'
  mapping:
    error_level:
      type: string
      label: 'Error messages to display'

system.menu:
  type: mapping
  label: 'Menu settings'
  mapping:
    active_menus_default:
      type: sequence
      label: 'Active menus'
      sequence:
        - type: string
          label: 'Menu'

system.performance:
  type: mapping
  label: 'Performance settings'
  mapping:
    cache:
      type: mapping
      label: 'Caching'
      mapping:
        page:
          type: mapping
          label: 'Page cache'
          mapping:
            enabled:
              type: boolean
              label: 'Cache pages for anonymous users'
            max_age:
              type: integer
              label: 'Max age of page cache'
    css:
      type: mapping
      label: 'CSS performance settings'
      mapping:
        preprocess:
          type: boolean
          label: 'Aggregate CSS files'
        gzip:
          type: boolean
          label: 'Compress CSS files'
    js:
      type: mapping
      label: 'JavaScript performance settings'
      mapping:
        preprocess:
          type: boolean
          label: 'JavaScript preprocess'
        gzip:
          type: boolean
          label: 'Compress JavaScript files.'
    response:
      type: mapping
      label: 'Response performance settings'
      mapping:
        gzip:
          type: boolean
          label: 'Compress cached pages'
    stale_file_threshold:
      type: integer
      label: 'Stale file threshold'
    theme_link:
      type: boolean
      label: 'Force inline link rendering'

system.rss:
  type: mapping
  label: 'Feed settings'
  mapping:
    channel:
      type: mapping
      label: 'Feed channel'
      mapping:
        description:
          type: text
          label: 'Feed description'
    items:
      type: mapping
      label: 'Feed items'
      mapping:
        limit:
          type: integer
          label: 'Feed item limit'
        view_mode:
          type: string
          label: 'Feed content'
    langcode:
      type: string
      label: 'Default language'

system.theme:
  type: mapping
  label: 'Theme settings'
  mapping:
    admin:
      type: string
      label: 'Administration theme'
    enabled:
      type: sequence
      label: 'Enabled themes'
      sequence:
        - type: string
          label: 'Theme'

system.timezone:
  type: mapping
  label: 'Time zone settings'
  mapping:
    default:
      type: string
      label: 'Default time zone'
    user:
      type: mapping
      label: 'User'
      mapping:
        configurable:
          type: boolean
          label: 'Users may set their own time zone'
        default:
          type: integer
          label: 'Time zone for new users'
        warn:
          type: boolean
          label: 'Remind users at login if their time zone is not set'

menu.menu.*:
  type: mapping
  label: 'Menu'
  mapping:
    id:
      type: string
      label: 'Menu identifier'
    label:
      type: label
      label: 'Menu label'
    description:
      type: label
      label: 'Menu description'
    langcode:
      type: string
      label: 'Default language'