So, currently when one posts something on Facebook, the visibility dropdown presents four different privacy options: Public, Friends, Only Me, and Custom (as well as any friend lists one has defined). But there used to be another choice, Friends of Friends, which has been absent for me for ages, maybe one or two years now. What puzzles me is that some of my friends still manage to post stuff with this Friends of Friends visibility  is it simply because they've had it as the default since the days when it still was there for choosing, and they never changed it, or can is still be activated somehow? I sort of really miss it.
Facebook: allowing friends of friends (but not the whole world) to see my posts
facebook;facebook timeline
Friends of Friends is still there. It's just under the Custom option.Type Friends of Friends in the These people or lists field. (It will probably be pre-selected for you.)