Sites using public-key-pins-report-only:
3,326 proton.me
6,786 protonmail.ch
8,624 protonmail.com
23,968 ddos-guard.net
96,953 protonvpn.ch
218,012 hackthissite.org
313,787 pm.me
349,187 proton.ch
390,060 peterjin.org
452,592 intellicureehr.com
495,682 patton.com
817,189 twfeg.org