isUserVerifyingPlatformAuthenticatorAvailable

Thank you very much for your support, @Systems Engineer . I tested this issue with iOS 26.2 RC, released on December 4, 2025 (https://developer.apple.com/documentation/ios-ipados-release-notes/ios-ipados-26_2-release-notes). In Safari, the behavior is now correct and isUserVerifyingPlatformAuthenticatorAvailable() returns true. However, in WKWebView, the behavior remains unchanged and it still returns false. Is there any additional information you need from me to further investigate this issue? Thanks again for your assistance.

There are two things at play here: In iOS 26.2 and macOS 26.2, we changed the behavior of isUserVerifyingPlatformAuthenticatorAvailable() to better match the intentions from the spec. Previously, it almost always returned true. Starting in these OSes and Safari 26.2, it now only returns true when the user has at least one passkey manager set up. In a previous beta version of 26.2, there was an issue where Safari would always return false. This should be fixed in the current beta to now respect the above behavior.

Hi, Thanks for the confirmation about the attStmt. Looks like the flow for RP during Passkey enrollment is, Check for isUserVerifyingPlatformAuthenticatorAvailable to show the Passkey enroll button Take the user through an enrollment and then reject the enrollment if it has an attStmt(implying it is a non syncing platform authenticator and thus not a Passkey)? Understand providing this signal is being discussed at the spec level as u mentioned but meanwhile double checking to make sure there is no better way to figure out Passkeys without taking the user through a enrollment.

I recently ran into some issues using WebAuthn in the context of WKWebView and happened to run across the answer to your question. I ran into this while investigating this bug: https://bugs.webkit.org/show_bug.cgi?id=237380a Per comments from WebKit devs on that bug, WebAuthn is not supported in WKWebView unless your app specifically has the Web Browser entitlement in which case it is then enabled. Also, if you invoke WebAuthn-related functions like navigator.credentials.create() or window.PublicKeyCredential.isUserVerifyingPlatformAuthenticatorAvailable() there is a bug where the promise returned from those methods in a WKWebView context on iOS never resolves. I ended up working around it by executing the initial isUserVerifyingPlatformAuthenticatorAvailable() in a Promise.race() with a timeout so that I could at least determine that WebAuthn was not supported in that context. Hope this helps, Kevin Flanagan

Should this work on Catalina (10.15.6)? I tried Safari Beta (Version 14.0 (15610.1.28.1.7, 15610), and have the appropriate experimental features set, but isUserVerifyingPlatformAuthenticatorAvailable() is always false. Using Chrome browser on same laptop I get true (and can register and authenticate using touch id). Does this only work in Safari on Big Sur?