Mathias Biilmann Christensen
Be Afraid Of HTTP Public Key Pinning (HPKP)
Between October 21st and 25th, Smashing Magazine became completely unavailable for a majority of visitors. Visiting Smashing Magazine would give most returning visitors with a modern browser a security warning message like this:
Some people would get a slightly different screen because of Smashing Magazine’s Service Worker kicking in, and showing a placeholder “You’re Offline” message, but the underlying cause was the same: HTTP Public Key Pinning.
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