Screensaver Settings

[Efficient_Good_5784]

On the server side the settings with backdrop as screensaver and the timings is functioning, but these settings seem to have no effect on the client side.

I want to clear up some confusion on your end.

There's two places where you can set settings with Jellyfin:

1. The dashboard
   
2. Client settings
   

The dashboard settings is the server settings (and as such, applies to your whole server).

The client settings are reachable by clicking on your profile picture on the upper-right of your screen on the normal web UI.
These settings (as the name suggests) only apply to the current client. You're confusing the web UI accessible from your web browser. It also counts as a client, so those settings will only apply to that browser session.
That's the reason those settings do not apply to any other client that you use.