I'm going with Revealing being one of the data professionals making a lot of moola by convincing small organisations that they need a wagonload of paperwork in place or the ICO will ruin them.
Just to clarify a couple of things that came up since my last post:
1 At this point, FB group admins do NOT hold any GDPR related responsibility for any content in their groups or for data held by fb on groups members. Fb have been explicit about this. I'd hate for group admins to go away from this thread thinking they need to leave the platform because of bogus GDPR bogeymonsters.
2 The person who shared the list does not appear to have broken any fb t&c. Happy to be corrected inthst if someone can find it, but I've had a good hunt through and can't find it mentioned anywhere.
3 The person who shared the list does not appear to have breached any data protection either. The only material fact made public was the membership of the group, and the public profile data. Their membership of the group would be held to be FB data, and there is no committment anywhere in their terms to treat group memberships as private personal information. It will be covered by their usual caveat that anything you post or do on fb belongs to them and unless you specifically make it private it's fair game. Since group membership cannot be hidden from other members of the group by joining the group you consent to them knowing you are in it.
Reveal I get where you're coming from and I'm sure it's a good place. If it helps, I was accused of scaremongering earlier this week for saying that GC activists were leaving themselves vulnerable to infiltration and malicious allegations. I totally want to go nur nur nur nur told you so, but then I worried that someone would decide I'd done it all just to prove my point or something equally daft. I do agree that there is a certain amount of naivety around the likelihood of malicious accusations and hence police interest, but I don't think GDPR is a realistic concern for them at this point.