{
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Undo",
  "actor": {
    "id": "tag:example.com,2001:follower"
  },
  "object": {
    "@context": "https://www.w3.org/ns/activitystreams",
    "type": "Follow",
    "actor": "tag:example.com,2001:follower",
    "object": {
      "url": [
        "tag:example.com,2001:followee",
        "extra-url"
      ]
    }
  }
}
