import SwiftUI struct ContentView: View { var body: some View { NavigationStack { Text("XX") .toolbar { ToolbarItem(placement: .bottomBar) { Text("YY") } } } } } Here is an even simpler ContentView that demonstrates the same error. This occurs for both iOS 26.4 and iPadOS 26.4 The output generated in the Xcode console is: 'UIKitToolbar' as a subview of UIHostingController.view is not supported and may result in a broken view hierarchy. Add your view above UIHostingController.view in a common superview or insert it into your SwiftUI content in a UIViewRepresentable instead.