Integrated Onlyoffice stuck in loading the Document

Hey,

I’ve updated to Nextcloud 18 and wanted to try the Onlyoffice Integration with the Community Documentserver.

When I activate the “Community Documentserver”-App, I get 2 Errors in the logging

Now when I try to open a Document, Only Office just loads infinitely without creating new Log Entries.

I host Nextcloud on a Debian 10 Server and use PHP7.3

Same for me. I installed the Only Office Community Document Server and this error message appear in the logs. No file is loading.