This is what I get when I `cat /etc/hosts | grep facebook`. Not all are Facebook

  0.0.0.0 facebook.com
  0.0.0.0 www.facebook.com
  0.0.0.0 facebookinc.122.2o7.net
  0.0.0.0 ncaafacebook.com
  0.0.0.0 www.ncaafacebook.com
  0.0.0.0 wwwfacebook.com
  0.0.0.0 www.wwwfacebook.com
  0.0.0.0 facebook-proxy.hi5.com
  0.0.0.0 facebook-repto1040s2.ahlamountada.com
  0.0.0.0 facebook.cm
  0.0.0.0 www.facebook.cm
  0.0.0.0 www.facebook.realtorarcf.com
  0.0.0.0 facebookasciiart.com
  0.0.0.0 www.facebookasciiart.com
  0.0.0.0 facebookbox.com
  0.0.0.0 www.facebookbox.com
  0.0.0.0 facebookcrawl.co.cc
  0.0.0.0 www.facebookcrawl.co.cc
  0.0.0.0 facebookloginsignin.com
  0.0.0.0 www.facebookloginsignin.com
  0.0.0.0 facebookoxy.com
  0.0.0.0 www.facebookoxy.com
  0.0.0.0 facebooktbtoolbar.ourtoolbar.com
  0.0.0.0 facebookunblocking.com
  0.0.0.0 www.facebookunblocking.com
  0.0.0.0 hacking-facebook.com
  0.0.0.0 www.hacking-facebook.com
  0.0.0.0 needfacebook.com
  0.0.0.0 www.needfacebook.com
  0.0.0.0 unblockfacebook.co.uk
  0.0.0.0 www.unblockfacebook.co.uk
  0.0.0.0 facebook-zdjecia.bo.pl
  0.0.0.0 zdjecia-facebook.bo.pl
  0.0.0.0 facebook-color.5v.pl
  0.0.0.0 podgladfacebook.wirtualnie.pl
  0.0.0.0 facebook-uzaleznienie.wirtualnie.pl
  0.0.0.0 facebookpodglad.wirtualnie.pl
  0.0.0.0 facebookszpieg.glt.pl
  0.0.0.0 pl-facebook.com--contest.co
  0.0.0.0 facebookcolor.pl
  0.0.0.0 www.specials.facebook.netsa.pl
  0.0.0.0 ilenafacebooku.pl
  0.0.0.0 facebook-app.pl
  0.0.0.0 facebookred.pl
  0.0.0.0 facebookfriends.com.pl
  0.0.0.0 ktopodgladamnienafacebooku.wordpress.com
  0.0.0.0 5facebookfrienddel.blogspot.com
  0.0.0.0 facebookkoloruj.blogspot.com
  0.0.0.0 aktualizacjafacebooka.blogspot.com
  0.0.0.0 facebookaplikacje.blogspot.com
  0.0.0.0 facebook-kolor.blogspot.com
  0.0.0.0 facebookkviewer.blogspot.com
  0.0.0.0 creative.ak.facebook.com
  0.0.0.0 pixel.facebook.com
  0.0.0.0 ads.ak.facebook.com
  0.0.0.0 ads.ak.facebook.com.edgesuite.net

And my rule in 1Blocker is

  https?://([a-z\.]*)?facebook\.com.*

@netaddict list is better.