SOLVED: Jellyfin dashboard not saving https enabled checkbox

[TheDreadPirate]

Further down in the networking page, there is a field to provide a certificate. Jellyfin is picky about the format this needs to be in. Without a valid, supported, cert in that field you cannot enable https in Jellyfin.

However, if you are already using tailscale there is no need for https in Jellyfin. The traffic is already encrypted as it traverses the VPN. Enabling https would only be necessary if the VPN exit is not on the same host or not on a host in the same network as your Jellyfin server. If that is the case, using a reverse proxy to handle https connections is preferable to using Jellyfin's built in https server. It is not configurable to restrict clients to strong ciphers not hardened against TLS attacks.