I encountered the same situation, but the version is Xcode 27 Beta 6, and the device is iOS 17. The minimal reproducible code is as follows: import SwiftUI import WidgetKit @main struct Xcode27LACrashApp: App { @Environment(.isActivityFullscreen) private var isActivityFullscreen var body: some Scene { WindowGroup { Text(isActivityFullscreen ? fullscreen : not fullscreen) } } } Crash info: dyld[712]: Symbol not found: _$s7SwiftUI17EnvironmentValuesV9WidgetKitE20isActivityFullscreenSbvg Referenced from: <6C188284-51F7-38B5-833C-13FDC11E4C2C> /private/var/containers/Bundle/Application/71A82AE6-495A-45AA-B823-A2E2597D6F6E/Xcode27LACrash.app/Xcode27LACrash.debug.dylib Expected in: <064E500D-3AE0-34EC-9759-52B592E7B15A> /System/Library/Frameworks/WidgetKit.framework/WidgetKit FB24532892
Topic:
Developer Tools & Services
SubTopic:
Xcode
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