Browser can find the domain and resolve the ip properly and load content. The app just says it can’t find anything.
How can I debug it?
Are you using the correct http/https syntax?
Yes
What is the app running on? Can a browser on that device find the URL?
Android and android tv. Both devices don’t work.
Yes, a browser on thr android device works. Other services resolve correctly with the same domain.
Do you have an authentication frontend like Authelia in front of your Jellyfin domain? Apps often break with that extra security layer in front.
No, I’ve got a reverse proxy (nginx proxy manager) with no custom authentication.
It even used to work in the apps.
Are you using https? On mine the app doesn’t allow just http.
Yes
Device/app?
Can the device resolve the server name? That’s handled by the OS, not apps.
Android and android tv. Both have problems within the app.
Yes, domain gets resolved correctly by browser