I have a firefox version, and a safari one in the works. It has about 50 users on firefox and 1500 on chrome.
It works a bit differently to most content blockers, you can take a look here if you're interested:
Anyway, the whole point is to allow people to get out of addictive loops, to take control of how they use the web, and most people aren't that tech savvy — they deserve to not be addicted to facebook too.