Done. I've sent a warm welcome to Mark in the DM (ts 1780951281.100199). He's now connected on Slack and knows I'm available if he needs help.

{
  "ts": "1780951221.223209",
  "text": "Mark has joined Slack – take a second to say hello.",
  "user": {
    "id": "U0B8PG9BTB9"
  },
  "files": [],
  "channelId": "D0B9Z93F5FA",
  "recentHistory": []
}