I also set up jitsi, in my case on an ubuntu server 18.04 VM on my desktop [0]. Took about 10 minutes as well to follow that guide.

In addition, I wanted to expose jitsi to the internet but not allow random people to create or join rooms. I basically followed the first part of this[1], which sets up username/password pair that you're prompted for each time you create/join a room.

edit this file:

    /etc/prosody/conf.avail/HOSTNAME.com.cfg.lua

Look for the first `authentication` line for HOSTNAME.com and change it to `internal_plain`

    authentication = "internal_plain"

Add a username/password

    prosodyctl register 'username' 'HOSTNAME.com' 'password'

then restart prosody (or just reboot)

This is enough to make a password prompt pop up every time someone creates or joins a room, and it autofills nicely after you enter it the first time on firefox/chrome/android app. If you follow the rest of the guide you can set up a second domain people can use to join rooms without a password prompt.

This makes me feel a bit better about exposing this to the internet. Not sure if there's other havoc someone could cause though.

[0] thankfully I have fast internet with a public IP

[1] https://github.com/jitsi/jicofo#secure-domain