Chrome Version: Version 72.0.3589.0 (Official Build) canary (64-bit)
OS: macOS 10.13.6

What steps will reproduce the problem?
(1) Using MacBook Pro with Touch ID, open https://webauthndemo.appspot.com
(2) Press "Register platform authenticator" button
(3) OS native fingerprint dialog appears, use Touch ID

What is the expected result?
OS fingerprint dialog disappears, WebAuthn dialog closes and complete registering platform authenticator.

What happens instead?
OS fingerprint dialog disappears, but WebAuthn dialog remain there and won't close until you cancel it. the platform authenticator is not regsitered.



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