{
  "$ref": "core/state_event.json",
  "state_key": "@alice:example.org",
  "type": "m.room.member",
  "content": {
    "membership": "join",
    "avatar_url": "mxc://example.org/SEsfnsuifSDFSSEF",
    "displayname": "Alice Margatroid"
  }
}