Apple has rolled out the beta 2 for iOS 13.3 which brings new Safari feature that supports NFC, USB, and Lightning FIDO2-compliant security keys. The iOS version is currently available only to developers and public beta testers.
Apple details in the iOS 13.3 beta 2 release note that the update: "Now supports NFC, USB, and Lightning FIDO2-compliant security keys in Safari, >SFSafariViewController, and ASWebAuthenticationSession using the WebAuthn standard, on devices with the necessary hardware capabilities."
Essentially, with the latest beta update, Safari will support physical security keys like the Lightning-equipped YubiKey, which can be used for more secure two-factor authentication.
For the uninitiated, Yubikey is a security tool for browsers, where in you do no need to enter a security code " you can just plug it into an iPhone or Mac to authenticate. FIDO2 is also a hardware security key for two-factor authentication. The support for the FIDO2-compliant security key was added to Safari 13 in macOS.
Other NFC, USB, and Lightning-based security keys will also work with Safari following the iOS 13.3 update.
Currently, there is no news on when the iOS 13.3's stable version can be expected, but many reports suggest that the rollout can be expected in December this year.