Why the backgroundExtensionEffect() seems to enabled by default seems to be a bug somewhere. I most certainly do not enable it anywhere and my understanding is that then I should not see this background anywhere at all. The fact that it shows up randomly for some of my detail views probably confirms that there's a bug. No, I will not spend more time and create a bug report along with a full project that demonstrates this bug, as likely it will not show up in a simple demo app.

Based on the docs this should be what I really want: https://developer.apple.com/documentation/swiftui/view/backgroundextensioneffect(isenabled:) It's supposed to disable the background, but it seems to not do anything at all. The code in the commented out region is still the only that works reliably. NavigationSplitView(sidebar: { sidebarView //.background { // Color.red // .edgesIgnoringSafeArea(.all) //} }, detail: { detailView .backgroundExtensionEffect(isEnabled: false) })

Ok, got a solid background with: sidebarView .background { Color.red .edgesIgnoringSafeArea(.all) } Still some of my detail views cause there to be narrow artefacts on the left side of the sidebar that are remnants of the mirrored content. This looks really ugly but at least the sidebar is legible now. Is there some way to not have the detail view background messing with the sidebar area at all?

I had hoped that maybe this could fix the background bug: NavigationSplitView(sidebar: { sidebarView .presentationBackground { SwiftUI.Color.red } }, detail: { detailView }) } Unfortunately that has no effect and the docs for the presentationBackground() modifier are... not too informative.

Clearly Apple doesn't care about this bug. Could it be that SiwA is deprecated?

Resurrecting an old thread, as this doesn't seem to be how it works, at least not nowadays. % unzip MyApp.ipa % codesign -d --entitlements :- Payload/MyApp.app ... <key>get-task-allow</key> <false/> ... If I save the entitlements to a file: % unzip MyApp.ipa % codesign -d --entitlements entitlements.plist Payload/MyApp.app and just flip the value of the get-task-allow flag and then resign: % codesign --entitlements entitlements.plist -s "iPhone Distribution" -f Payload/MyApp.app Payload/MyApp.app: replacing existing signature and then install the app I get: WARNING: could not locate iTunesMetadata.plist in archive! WARNING: could not locate Payload/Tester.app/SC_Info/Tester.sinf in archive! Copying 'MyApp.ipa' to device... DONE. Installing 'com.....' Install: CreatingStagingDirectory (5%) Install: ExtractingPackage (15%) Install: InspectingPackage (20%) Install: TakingInstallLock (20%) Install: PreflightingApplication (30%) Install: InstallingEmbeddedProfile (30%) Install: VerifyingApplication (40%)ERROR: Install failed. Got error "ApplicationVerificationFailed" with code 0xe8008016: Failed to verify code signature of /var/installd/Library/Caches/com.apple.mobile.installd.staging/temp.AmySH8/extracted/Payload/MyApp.app : 0xe8008016 (The executable was signed with invalid entitlements.) If I don't change anything in entitlements.plist but just resign with the same entitlements then the app installs ok, but can not be started via USB. So, it's not possible to flip the flag and resign. My understanding is that somehow the get-task-allow entitlement must be present in the provisioning profile, but I have not found out any way to actually make this happen. Any ideas for what I can do?