Today, Microsoft announced that it's introduced the Web Authentication spec in its Edge browser in the latest Windows 10 Insider Preview, which is build 17723. The goal is to create a future that doesn't include passwords, something that pretty much all tech companies have been working toward for some time.
Users will be able to use their face, fingerprint, PIN, or FIDO2 devices to log into websites. Microsoft actually says that this is the most complete implementation of Web Authentication to date, as it supports the largest variety of devices.
Microsoft first announced its plans to do this back in April 2016. It introduced an early implementation of the standard back then, before the Windows 10 Anniversary Update was even available, but now it should be more complete.
Obviously, it's only included in the latest Windows 10 Insider Preview in the Fast ring. The latest Slow ring release is build 17713.1002, and that was only released four days ago, so don't expect to see this feature in the Slow ring anytime soon. If you're not an Insider, you should see this feature in the fall when Redstone 5 is released.