If I understand correctly you can create a new viewController , link it to your main one with a "show segue" , then you click on your new controller and in "presentation" you can choose "page sheet", so you kinda have a new view controller over your main one where you can perform your signIn/signup
DanielJamesTronca
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You can create a stackView and link with your ViewController and create appleSignIn button programmatically
Then you can check iOS version and add it to your stackView
if #available(iOS 13.0, *) {
/*	iOS13 available add button! */
self.stackView.addArrangedSubview(appleSignInButton)
} else {
/* continue */
}
This is the best approach to handle the button with lower version of iOS!