The article is about a mechanism for the OS to validate focus requests. The application with the link requests a focus token, and passes it to the browser along with the open-link request, and the browser can then request focus.
It isn't perfect, because there's no way to know that the browser isn't using the token to request focus for something else, but maintaining and validating chain of custody for focus across applications is exactly the problem it looks like they are working on solving.
It isn't perfect, because there's no way to know that the browser isn't using the token to request focus for something else, but maintaining and validating chain of custody for focus across applications is exactly the problem it looks like they are working on solving.