What is "Document Domain"

Description

I have a very simple question. I am wondering what “Document Domain” is under the General settings in Administration and what is it used for and where?

Server Setup Information

  • Version of Rocket.Chat Server: 3.0.12
  • Operating System: Linux
  • Deployment Method: Docker
  • Number of Running Instances: 1
  • DB Replicaset Oplog: Enabled
  • NodeJS Version: v12.14.0
  • MongoDB Version: 4.0.17
  • Proxy: nginx
  • Firewalls involved: Yes, network perimeter. Server is NATed.

Any additional Information

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