Oh I see. I confused Cloudflare Tunnel with Cloudflare Access.
Yes Cloudflare Tunnel can work with Jellyfin apps, but: 1) this exposed your Jellyfin to the world, and you are one vulnerable away to get owned, and 2) like other sibling posts mentioned, this is against their ToS to host streaming service on free plan on their platform.
Yes Cloudflare Tunnel can work with Jellyfin apps, but: 1) this exposed your Jellyfin to the world, and you are one vulnerable away to get owned, and 2) like other sibling posts mentioned, this is against their ToS to host streaming service on free plan on their platform.