A thorough article on the current challenges, technically and ethically, regarding the use of elsewhere published public data that can be regarded as 'personal data' in the GDPR/DSGVO sense. Data that will be published for example by pulling in likes, shares and comments posted on Twitter here in my blog, as 'reactions' alongside with 'real' comments on my posts.

As Sebastian writes

Just the fact that I can aggregate a “facepile” showcasing everybody who clicked “like” on a tweet of mine does not mean that my motivations for doing so are more important than their right to stay in control

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