Jellyfin not shown in DLNA discovery

[ebbi]

Not sure if this is related, it looks like you didn't set the correct password for your cert.  But you should avoid using the built in HTTPS functionality in jellyfin anyway.  Disable https.  If you need https for remote access, I'd recommend using a reverse proxy like Caddy or Nginx to handle remote connections.

Get rid of these options in your compose.  They are not needed when using host networking.

Code:

    ports:                             
      - "8096:8096/tcp"                # http
      - "8920:8920/tcp"                # https
      - "1900:1900/udp"                # service auto-discovery
      - "7359:7359/udp"                # auto-discovery

Oh! I have no idea which cert this could be.
https is not used in Jellyfin, everything is local only.
I included these ports, as I wasn't aware of the DLNA plugin. 

Try binding Jellyfin to 192.168.2.2.  Dashboard > Networking > Bind to local network address.  I'm assuming that is a static IP.

Jellyfin uses the same IP as the Synology.
It is "half-static": a fixed DHCP address.

Anyway, I need to postpone tests for tomorrow, as I'm not home right now and cannot test the mobile devices.
I connected remotely to my Windows and tested with VLC and it has worked from there.
But after a while it seems to stop and Jellyfin isn't visible in UPnP anymore.