I still got collabora NOT working with my Nextcloud server. I'm a tech savvy, so I don't understand why it's so hard to setup a dedicated office server and let it work together with Nextcloud. I tried both the standalone setup which should include the server as well as the manual server setup.

I'm no more doubting about myself, but the setup/documentation seems broken at best. Sometimes the documents just don't want to open, while I did see the web office interface.