Our app signs users up through ASWebAuthenticationSession (not ephemeral). The sign-up page is a normal HTML form that posts to our server. When sign-up succeeds, the server redirects to our custom-scheme redirect_uri, which closes the session, as expected. When the user types a password and submits, iOS shows the "Save Password?" modal inside the session. From there, iOS 26 and iOS 27 behave differently: iOS 26.5: iOS waits. The form isn't sent until the user answers the modal. Then the request goes out, the redirect closes the session, and the password has been saved. iOS 27.0 and 27.2 beta 2: iOS doesn't wait. The form is sent right away, the redirect closes the session in under a second, and the modal disappears with it. The user never gets to tap Save. Things we checked: Same server, same page, same device, same app build. Only the iOS version changes the result. prefersEphemeralWebBrowserSession is off. Safari itself never waited on neither versions. The waiting only happened inside ASWebAuthenticationSession. Saving passwords still works on the device otherwise, and every test used a new account and password. Questions: Is the iOS 27 behaviour intended? If so, is there any supported way to let the user answer the sheet before the redirect closes the session? If it's a bug, is it tracked somewhere? The only fix we've found is to show an extra page after sign-up and only redirect from there, which adds a step for every user. We'd rather not ship that if the iOS 26 behaviour is coming back.