static-cms/packages/netlify-cms-widget-list/src/schema.js

export default {
  properties: {
    allow_add: { type: 'boolean' },
    collapsed: { type: 'boolean' },
    summary: { type: 'string' },
    minimize_collapsed: { type: 'boolean' },
    label_singular: { type: 'string' },
    i18n: { type: 'boolean' },
  },
};