SwiftUI View Stops Updating When Using @Environment(.scenePhase)

Using Swift
1

I'm experiencing a bug where my SwiftUI views stop updating when I enable @Environment(\.scenePhase) in the @main App struct.

Here’s a simplified version of the code:

import SwiftUI

public class Backend {
    public init() {}
}

@main
struct swiftuibugApp: App {
    //@Environment(\.scenePhase) var scenePhase // <--- uncomment for bug
    
    let backend = Backend()
    
    var body: some Scene {
        WindowGroup {
            RouterView(
                backend: backend,
                setup: .generic
            )
        }
    }
}

When the @Environment(\.scenePhase) property is commented out, everything works as expected and the view updates properly. As soon as I uncomment that line, the view stops responding to state changes, as if the view is frozen or no longer observing the underlying model.

I’m not using scenePhase anywhere in the code yet—just declaring it seems to be enough to trigger the issue.

Environment:

  • Xcode version: 16.3
  • iOS version: 18.4

Source code:

2

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