Differences between 'connected' and 'uj' message?

Description

Not an issue, but more like questions. I’m using the forward feature of rocket.chat. It’s quite evident in the source code that the server will respond with 3 messages, in the following order:

  1. A message with payload contains msg: ‘connected’
  2. A message with payload contains t: ‘ul’
  3. A message with payload contains t: ‘uj’

Source: Helper.js, RoutingManager.js and rocket.chat/app/models/server/models/Messages.js

I’d like to ask:

  • What are the differences between 1. and 3. ? As far as I know, 1. is sent from the server when an agent take a room. I receive .3 only when I use forward room.
  • Should forwarding a room send both of these message?

All answers are appreciated.

Server Setup Information

  • Version of Rocket.Chat Server: 2.1.0
  • Operating System: linux
  • Deployment Method: tar
  • Number of Running Instances: 2
  • DB Replicaset Oplog: Enabled
  • NodeJS Version: v8.11.4
  • MongoDB Version: 4.0.12
  • Proxy: nginx
  • Firewalls involved: no

Any additional Information

NA