Minimum steps to adding a virtual host to nginx / meet

What would be the minimum configuration changes in a working config to add a ‘virtualhost’.

I have tried this:

copy /etc/nginx/sites-enabled/meet.domaina.com.conf to /etc/nginx/sites-enabled/meet.domainb.com.conf
And change the server_name from meet.domaina.com to meet.domainb.com

(I think I can leave the bosh url, because that is just the proxy connection)

Because the meet config has also an url that needs to match I have to change location = /config.js to point to a new copy
/etc/jitsi/meet/meet.domainb.com-config.js

and change in this copy /etc/jitsi/meet/meet.domainb.com-config.js
the bosh url
bosh: //meet.domainb.com/http-bind

However this is not enough, and I have the reload of home room page.

What else do I need to change (except of course of doing a complete domainb.com copy)

First error in the js console is
XML Parsing Error: mismatched tag. Expected: .
Location: https://meet.domainb.com/http-bind?room=test3
Line Number 4, Column 3:

copy the prosody config meet.domaina.com.cfg.lua to meet.domainb.com.cfg.lua and change only the VirtualHost “meet.domainb.com

Should do it.