collabora

1. Proxy settings — SDK https://sdk.collaboraonline.com/ documentation
2. owncloud.DOM.TLD/index.php/apps/market/#/app/richdocuments 
3. owncloud.DOM.TLD/index.php/settings/admin?sectionid=additional 
4. echo 'deb https://collaboraoffice.com/repos/CollaboraOnline/CODE-deb/ ./' | tee /etc/apt/sources.list.d/collabora.list\napt-key adv --keyserver keyserver.ubuntu.com --recv-keys 0C54D189F4BA284D\napt update
5. ai libreoffice libcurl4-gnutls-dev libxml2-dev libkrb5-dev loolwsd code-brand
6. sc-restart coolwsd; sc-status coolwsd
7. vim /etc/coolwsd/coolwsd.xml

/etc/nginx/sites-available/collabora

server {
   server_name DOM.TLD;
   location / {
       proxy_pass http://10.0.3.LXCIP:9980;
       proxy_set_header Host $http_host;
       proxy_set_header X-Real-IP $remote_addr;
       proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
       proxy_set_header X-Forwarded-Proto https;
       proxy_buffering off;
   }
   listen 80;
# static files
location ^~ /browser {
  proxy_pass http://10.0.3.LXCIP:9980;
  proxy_set_header Host $host;
}
# WOPI discovery URL
location ^~ /hosting/discovery {
  proxy_pass http://10.0.3.LXCIP:9980;
  proxy_set_header Host $host;
}
# Capabilities
location ^~ /hosting/capabilities {
  proxy_pass http://10.0.3.LXCIP:9980;
  proxy_set_header Host $host;
}
# main websocket
location ~ ^/cool/(.*)/ws$ {
  proxy_pass http://10.0.3.LXCIP:9980;
  proxy_set_header Upgrade $http_upgrade;
  proxy_set_header Connection "Upgrade";
  proxy_set_header Host $host;
  proxy_read_timeout 36000s;
}
# download, presentation and image upload
location ~ ^/(c|l)ool {
  proxy_pass http://10.0.3.LXCIP:9980;
  proxy_set_header Host $host;
}
# Admin Console websocket
location ^~ /cool/adminws {
  proxy_pass http://10.0.3.LXCIP:9980;
  proxy_set_header Upgrade $http_upgrade;
  proxy_set_header Connection "Upgrade";
  proxy_set_header Host $host;
  proxy_read_timeout 36000s;
}
}