It seems that the term "shadow profile" refers to a feature where Facebook retains contact information uploaded by other users in order to recommend them as friends if/when you create a profile [1]. For all the fear associated with the term, that's pretty benign. Is there any evidence for a link between these "profiles" and some of the more egregious claims of privacy infringement?
[1] https://www.zdnet.com/article/firm-facebooks-shadow-profiles...