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In another study, the FIDO Alliance found that passkeys are supported by 20% of the world’s top 100 websites and 12% of the top 250, with 13 billion accounts able (potential, not a fait accompli) to leverage passkeys for sign-in.
https://fidoalliance.org/content-ebook-consumer-password-and-passkey-trends-wpd-2024/

Convincing new selection from https://passkeys-directory.dashlane.com/ (for intro update):

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Added support to WhatsApp: https://faq.whatsapp.com/1850567238795036/?helpref=uf_share

maintained summary of WebAuthn support by various platforms and products: https://www.cisecurity.org/insights/blog/tracing-the-evolving-levels-of-support-for-webauthn

Implementation

Good hints on implementation and common misconceptions and problems: Corbado Blog - https://www.corbado.com/blog/passkey-implementation-pitfalls-misconceptions-unknowns

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