Not entirely unrelated: today on Facebook I noticed there are groups I can't browse without the group creator knowing which posts I have seen and which posts I

Not entirely unrelated: today on Facebook I noticed there are groups I can't browse without the group creator knowing which posts I have seen and which posts I haven't. https://www.facebook.com/help/?faq=409719555736128&in_context https://www.facebook.com/help/?faq=409719555736128&in_co... It might not be new but it was the first time I noticed it (and I immediately left the group without thinking about it for even one second).