Facebook quietly introduced new functionality onto its site last week that could have some worried about their online privacy.
The social network is rolling out the ability to see if and when someone has seen a post on a Facebook group.
For now you can still snoop on the profiles and pictures of your ex-partners (their privacy settings permitting) to keep a track - without them knowing - of how miserable their life has become since they split up with you.
But if you are in the same Facebook group (perhaps related to a school, club or joint interest), you can see both whether someone has seen a particular post and at what time they saw it.
So, although you can configure Facebook to not tell your online friends when you are online (effectively hiding from their instant messaging chats, and maintaining a pretence that you have a social life rather than being plugged into the internet constantly) they can still keep some track on what you are up to, and when, on Facebook.
I don't want to come across as a complete privacy zealot here. I can understand that there are justifiable explanations of why knowing if someone has read a group announcement could be very useful... but is there anyone else who agrees that Facebook just became a little less private?
Similar functionality already exists in the Facebook Messenger app, telling you if and when your contacts have read a message.
One wonders if this is a slippery slope, and whether Facebook will consider introducing the (desired by many, and dreaded by the privacy conscious and anonymous snoopers) ability to tell who has been checking out your Facebook profile?
When TechCrunch asked Facebook if the "Seen by" functionality would be ported over to the news feed, the site said it was "not going to discuss what we might (or might not) do in the future."
In the meantime, I've been unable to find any way to prevent Facebook from sharing whether I had read a group post, or share to users with the Messenger app if I had seen a message. I would, at least, have liked the option.
Once again, Facebook has become a little less private.
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