sudo apt install -y curl gnupg

You can verify the script download integrity with (requires sha256sum):

diff <( curl -s https://repo.jellyfin.org/install-debuntu.sh -o install-debuntu.sh; sha256sum install-debuntu.sh ) <( curl -s https://repo.jellyfin.org/install-debuntu.sh.sha256sum )

An empty output means everything is correct. Then you can inspect the script to see what it does (optional but recommended) and execute it with:

less install-debuntu.sh
sudo bash install-debuntu.sh

If you run into any dependency errors, run this and it will install them and jellyfin-ffmpeg.

sudo apt install -f
sudo apt install -y ffmpeg jellyfin-ffmpeg # jellyfin-ffmpeg might not be available and youi might have to install jellyfin-ffmpeg6 or jellyfin-ffmpeg5. I installed jellyfin-ffmpeg5.

HW acceleration

sudo apt install -y intel-opencl-icd intel-media-va-driver i965-va-driver mesa-opencl-icd

jellyfin desktop client

yay -S jellyfin-media-player