Extrinsic 8669-1

{
  "heartbeat": {
    "blockNumber": 8668,
    "sessionIndex": 144,
    "validatorsLen": 4,
    "authorityIndex": 3
  },
  "signature": "0x3aafc7d18930363c018fa54363be55a294b57ef2b9c90990d9de0138a9c0e711b7531c3492768c579c4dd6c590b6e17d40f55f4443c5169d1e75bfefaf9ffa81"
}