Unrecognised subtype: message_replied

[bwbaugh]

"{\"type\":\"message\",\"message\":{\"type\":\"message\",\"user\":\"UREDACTED\",\"text\":\"<@UREDACTED>: REDACTED\",\"thread_ts\":\"1526333638.000192\",\"reply_count\":3,\"replies\":[{\"user\":\"UREDACTED\",\"ts\":\"1526333810.000040\"},{\"user\":\"UREDACTED\",\"ts\":\"1526333869.000455\"},{\"user\":\"UREDACTED\",\"ts\":\"1526333898.000283\"}],\"unread_count\":3,\"ts\":\"1526333638.000192\"},\"subtype\":\"message_replied\",\"hidden\":true,\"channel\":\"CREDACTED\",\"event_ts\":\"1526333898.000318\",\"ts\":\"1526333898.000318\"}"
Error in $: Unrecognised subtype: message_replied
Please report this failure to the github issue tracker

Pretty printed JSON:

{
  "channel": "CREDACTED",
  "event_ts": "1526333898.000318",
  "hidden": true,
  "message": {
    "replies": [
      {
        "ts": "1526333810.000040",
        "user": "UREDACTED"
      },
      {
        "ts": "1526333869.000455",
        "user": "UREDACTED"
      },
      {
        "ts": "1526333898.000283",
        "user": "UREDACTED"
      }
    ],
    "reply_count": 3,
    "text": "<@UREDACTED>: REDACTED",
    "thread_ts": "1526333638.000192",
    "ts": "1526333638.000192",
    "type": "message",
    "unread_count": 3,
    "user": "UREDACTED"
  },
  "subtype": "message_replied",
  "ts": "1526333898.000318",
  "type": "message"
}