Stefan Arentz, July 2018
This repository contains Safari extensions for each of the blocklists that Firefox Focus supports. To keep things simple and without a UI, each blocklist is simply included in a separate extension.
Note that this is just the source - to run these in Safari they would have to be signed and published. I have not gone through that process. Also, I think extensions of this type are going to be deprecated with macOS 10.14.