2018-03-03 UTC
# 
tantek HPKP is HTTP Public Key Pinning, an abandoned standard for websites to tell browsers to only accept a certain certificate when communication. See also: https://blog.qualys.com/ssllabs/2016/09/06/is-http-public-key-pinning-dead https://www.theregister.co.uk/2017/10/30/google_hpkp/ etc.