Thank you, Just. You just confirmed that NC27.13 does not work with document server_community. Does creating a Doc Space at ONLYOffice and connecting ONLYOffice on the NextCloud to that server make any sense? The entire idea of hosting NextCloud is to ensure privacy. Hosting files at ONLYOffice Docs Space defeats the purpose. I might end up just be storing files in the NC and edit them locally.
I don’t personally use OnlyOffice, but afaik you should be hosting their server yourself.
Actually, what I found is a single person reported that app was not working for them on 27.1.3 but it includes no further details or logs to confirm anything.
I also see a new version of the nc connector app has not been released since nc25, so that would be a point of concern. Often such apps can be used on newer versions, but I’m also not personally using it. I would ask for clarification from onlyoffice directly: https://forum.onlyoffice.com/
Probably also worth confirming if this fix works for you from the readme:
If autoconfiguration fails for any reason, you may manually enter the url. Log in as the admin and go to Settings > ONLYOFFICE. For the ONLYOFFICE Docs address, enter the value in the format of https://<nextcloud_server>/apps/documentserver_community/.
You’ll also want to review your logs and such as mentioned in the linked support template above.