Error Dialog: Unerwarteter Fehler: Bad state: Missing etag in response

I’m migrating a KeePass 2.0 Database to AuthPass. Up until now I synced the DB via WebDav for a NextCloud-instance. I had no problems using AuthPass on my mobile devices and KeePass on my laptops/desktops.
As I’m losing access to the NextCloud-instance in a couple of days, I switch to saving to AuthPassCloud on my mobile devices with no problems.
The error occured on my laptop as I tried to open the saved database in the webapp. Any help troubleshooting this is appreciated.

title:null
content: Unerwarteter Fehler: Bad state: Missing etag in response. got: {content-length: [28929], content-type: [application/octet-set]} (200)
OS: web web
App Info: AuthPass (1.9.5+1873) [design.codeux.authpass.web]
Device: {userAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0}