Facebookquaintance
A Facebookquaintance is someone who knows your business but you don’t know theirs. They like your life but you don’t know why.
You posted a photo of your new car. They liked it. You didn’t know who they were. They might be your ex’s mom.
You posted about your breakup. They commented ‘That sucks.’ You didn’t know who they were. They might be your ex’s friend.
You posted about your new job. They said ‘Good for you.’ You didn’t know who they were. They might be your old teacher.