No, this is Google providing authentication with your Google account to third-party websites. If you are already logged into a Google account, it suggests that you log in with that account with a popup saying "Continue as <your name>" and shows your email and avatar.
It's an iframe so the website itself doesn't have access to your data, but this is not obvious just from looking at it - it looks like part of the site. To me it feels like it teaches users to trust websites in ways that make them susceptible to phishing.
Yeah, that’s why I dislike it as well. Imagine the same “sign in with google popup” but it’s just a floated div on the page. A user who uses the “continue as button” might be comfortable typing their password in there, thinking it’s part of the browser
It's an iframe so the website itself doesn't have access to your data, but this is not obvious just from looking at it - it looks like part of the site. To me it feels like it teaches users to trust websites in ways that make them susceptible to phishing.