Facebook login shows an additional confirmation popup on iOS 11

OK, so after several useless experiments I have been able to find a way to achieve what my client wanted. Aforementioned behavior is the result of a newer version of FBSDK. Once I downgraded from FBSDK 4.26.0 to 4.24.0 (Swift SDK version does not matter), the popup stopped showing. So if you are facing the same problem, and your clients (or you) don't want this popup, this might be a solution for you too.

I don't think facebook guys did this by accident, and this popup can allow some new iOS 11 feature. However, I was not able to distinguish any real new functionality - I only noticed that the newer version does not give you a choice if you want to login using native app or safari, but goes directly for the safari login. But since that was a requirement by my client as well, for me the choice was quite natural.

The message is a standard message used by SFAuthenticationSession to ask the user for permissions to access safari (excerpt from docs):

If an application uses SFAuthenticationSession, users are prompted by a dialog to give explicit consent, allowing the application to access the website's data in Safari.

UPDATE:

Apparently, Safari uses the "CFBundleName" property as the display name for this dialog. This is usually set to ${PRODUCT_NAME} which equals the last portion of your app's bundle identifier, but you can change it to whatever you like. Of course it is advisable to set it to the actual display name of your app.