Do you have other firewall applications running? Like Bitdefender?
Click Start > type Resource Monitor > click on the Network tab > Expand the Listening Ports table > find jellyfin.exe on port 8096. What does it say in the Firewall status column?
Jellyfin 10.10.6 (Docker)
Ubuntu 24.04.2 LTS
Intel i3 12100
Intel Arc A380
OS drive - SK Hynix P41 1TB
Storage
4x WD Red Pro 6TB CMR in RAIDZ1