editor_advanced_link-8.x-1.8/config/schema/editor_advanced_link.schema.yml

# Plugin \Drupal\editor_advanced_link\Plugin\CKEditor5Plugin\AdvancedLink
ckeditor5.plugin.editor_advanced_link_link:
  type: mapping
  label: 'Advanced Link'
  mapping:
    enabled_attributes:
      type: sequence
      orderby: value
      label: 'Enabled attributes'
      sequence:
        type: string
        label: 'Enabled attribute'
        constraints:
          Choice:
            callback: \Drupal\editor_advanced_link\Plugin\CKEditor5Plugin\AdvancedLink::validChoices