When subviews are enclosed in NavigationView, why do they shift upwards and downwards in SwiftUI?

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Subviews in NavigationView shift upwards and downwards because the NavigationView adds a navigation bar at the top which changes the layout of the subviews. The navigation bar takes up additional space, and SwiftUI automatically adjusts the layout to account for it. Additionally, when you scroll down in a view that has a navigation bar, the navigation bar will hide, causing the content to shift upwards to fill the empty space.