I feel for young teens/ students who post all kinds of rubbish on facebook with scant regard to who might read it. (Ie. school, future employer) Even older people do not realise that if you post something then your "friends" can share it and something can quickly be spread across the word. If you have contraversial opinons be sure who you share them with.
I had a shock when a post written by a TA at my son's school came up on my timeline. One of my "friends" had shared the post and commented on it. I am sure the TA never intended the post to read by parents of the kids that she worked with. I had never realised that the woman in question was a facist Britain First supporter. I find it frightening that she works with EAL kids and holds such views.
There is a theory that there is six aquaintances between everyone on earth. I imagine it could be quite possible for a head teacher to find themselves reading a post by a TA. If I was a head teacher and found out that a TA supported British First then I would not renew their contract if their role involved working with EAL children.