[zwog]

> I worked in some companies that had this popup, and the most common goal was to harvest email addresses for newsletters.

Ooh, I've never looked into it, but I would have thought that with this feature the website explicitly does NOT get my email address. Silly me, still believing some features are meant for the user.

[whstl]

For fairness, I just disabled my Ad Blocker to check, and the popup seems to have changed, but the previous popups were quite explicit about sharing your email with the website:

https://superuser.com/questions/1414410/how-to-disable-googl...

I can't confirm whether the email is still shared. It used to be the case from late 2010s up to a few years ago.

[bilekas]

While I don't consider myself an apple fanboy by any means they really did do a good job with their apple sign in, I don't know the full process but they seem to use an email from a pool of apple IDs for emails that prevent the app/service ever getting your real email.

It would be easy to assume that other oath providers are doing the same but absolutely not.

[whstl]

Yep, it uses an auto-generated @icloud.com for "Hide my Email" (useable in any website, or even if you want to give to someone in person) and @privaterelay.appleid.com when you use "Sign In With Apple".

This is quite visible in User Accounts where I work... while they do cause some issues from time to time (when the user disables the relay address for an active account), it guarantees privacy.

But I don't know if other popular single-sign-on provider do this.