Full app (auth page) launches within the widget page before Okta authentication

In some cases, during authentication in the Okta widget window, the application’s authentication page briefly appears, followed by the Okta authentication widget itself. This can be reproduced by clearing the application cache in the browser or by using incognito mode.
But when LocalStorage contains okta-cache-storage (it safe there I think in moment just before redirect in okta window) instead of app page → okta sign in page I have about:blank → okta sign in page and I want this behavior.