There are ways to get Docker running on an ARM-based Synology, it seems: https://stackoverflow.com/questions/52520008/can-i-install-docker-on-arm8-based-synology-nas
This is plain Docker, though. So you'll probably want to setup Portainer as well.
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There are ways to get Docker running on an ARM-based Synology, it seems: https://stackoverflow.com/questions/52520008/can-i-install-docker-on-arm8-based-synology-nas
This is plain Docker, though. So you'll probably want to setup Portainer as well.
You could add the Synocommunity as a package source, instructions here and then install Jellyfin from their repository in the Package Center. Jellyfin is available on their repository.
A disadvantage of this is that you're dependent on the maintainer of the package on the Synocommunity and it could take a while for new versions to be uploaded to their repository. If you use Docker, then you can basically get new versions immediately.
I used this version of Jellyfin for a long time and had no significant issues. The maintainer usually had new versions available within a week.