As for prevention, what I do is,....always make a dummy FB account and make that name as your friend, ( do not make any friends in that new account, except your original ID as a friend ) ) so now,
If due to complain or any reason, they block your original account ( which they always does on complaints ) at least in that one man show idle/backup account,...
If you click " Home" in top line,
you can see all of your posts ( forwarded to that, from the original account ) . Also in that new one man friend account ( with you as a friend only ) yr posts are also not been buried away .