Error when using internalLink annotation in Sanity Studio

Uncaught error
Could not resolve jsonType of undefined. No parent type found

Stack:

    at isJSONTypeOf (<http://localhost:3333/studio/static/js/app.bundle.js:231611:11>)
    at <http://localhost:3333/studio/static/js/app.bundle.js:231560:55>
    at Array.map (<anonymous>)
    at validateAnnotations (<http://localhost:3333/studio/static/js/app.bundle.js:231548:22>)
    at validateMarks (<http://localhost:3333/studio/static/js/app.bundle.js:231483:19>)
    at validateBlockType (<http://localhost:3333/studio/static/js/app.bundle.js:231440:13>)
    at visitors.reduce._objectSpread._problems (<http://localhost:3333/studio/static/js/app.bundle.js:230289:17>)
    at Array.reduce (<anonymous>)
    at <http://localhost:3333/studio/static/js/app.bundle.js:230288:21>
    at <http://localhost:3333/studio/static/js/app.bundle.js:230310:49>

(Your browsers Developer Tools may contain more info)

import React from 'react';

const InternalLinkRender = ({ children }) => <span>{children} 🔗</span>;

export default {
  title: 'Internal link to another document',
  name: 'internalLink',
  type: 'reference',
  description: 'Locate a document you want to link to',
  to: [{ type: 'page' }, { type: 'route' }],
  blockEditor: {
    icon: () => '🔗',
    render: InternalLinkRender,
  },
};

Uncaught Error: Could not resolve jsonType of undefined. No parent type found
    at isJSONTypeOf (isJSONTypeOf.js:16)
    at block.js:167
    at Array.map (<anonymous>)
    at validateAnnotations (block.js:155)
    at validateMarks (block.js:90)
    at validateBlockType (block.js:47)
    at visitors.reduce._objectSpread._problems (validateSchema.js:62)
    at Array.reduce (<anonymous>)
    at validateSchema.js:61
    at validateSchema.js:83