San Francisco — In May, Facebook casually invited me to join a conspiracy cult that believes the world is controlled by a Satan-worshipping, baby-eating, deep-state coterie and can only be saved by US President Donald Trump.

“Join groups to connect with people who share your interests,” the social media network implored in a recommendation e-mail. Below was a suggestion that I become part of a 135,000-strong Facebook group called “QAnon News & Updates — Intel drops, breadcrumbs & the war against the cabal”.

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