media_directories-2.x-dev/modules/media_directories_editor/config/schema/media_directories_editor.schema.yml

media_directories_editor.settings:
  type: config_object
  label: 'Media Directories Editor settings'
  mapping:
    embed_dialog:
      type: mapping
      label: 'Embed dialog settings'
      mapping:
        image_styles:
          type: sequence
          label: 'List of enabled image styles in embed dialog'
          sequence:
            type: string
            label: 'Image style'