First, congratulations on the project; it is amazing.
I have installed collabora on a server in my house (debian 10 and apache2) and only for home use.
There is a “reverse proxy” on the web server, which must redirect to the collabora server in a nextcloud.
If I open a port (for example 4443) from the router it works without problem. I have set up it in option 2 of the guide (Setting up Apache 2 reverse proxy - Collabora Office and Collabora Online).
But I only want to have port 443 open, which goes to the “reverse proxy” and it redirects to 4443 where is collabora server.
I can’t get it to work, and I don’t know if it’s my clumsiness setting up the “reverse proxy” or setting up “loolwsd.xml”