If you create a NavigationSplitView, then the sidebar is automatically adorned with a sidebar material effect. This affects the views background as well as any controls that are in the view. What is the correct way to disable this behaviour so that I can use a NavigationSplitView without the material effects being applied? The best I've come up with so far is to explicitly set the background on the sidebar but I'm curious if that's the correct way or I'm just getting lucky. struct ContentView: View { var body: some View { NavigationSplitView { // This works, but is it correct? SidebarView() .background(.windowBackground) } detail: { DetailView() } } }

I'm looking for clarification on a SwiftUI performance point mentioned in the recent Optimize your app's speed and efficiency | Meet with Apple video. (YouTube link not allowed, but the video is available on the Apple Developer channel.) At the 1:48:50 mark, the presenter says: Writing a value to the Environment doesn't only affect the views that read the key you're updating. It updates any view that reads from any Environment key. [abbreviated quote] That statement seems like a big deal if your app relies heavily on Environment values. Context I'm building a macOS application with a traditional three-panel layout. At any given time, there are many views on screen, plus others that exist in the hierarchy but are currently hidden (for example, views inside tab views or collapsed splitters). Nearly every major view reads something from the environment—often an @Observable object that acts as a service or provider. However, there are a few relatively small values that are written to the environment frequently, such as: The selected tab index The currently selected object on a canvas The Question Based on the presenter's statement, I’m wondering: Does writing any value to the environment really cause all views in the entire SwiftUI view hierarchy that read any environment key to have their body re-evaluated? Do environment writes only affect child views, or do they propagate through the entire SwiftUI hierarchy? Example: View A └─ View B ├─ View C └─ View D If View B updates an environment value, does that affect only C and D, or does it also trigger updates in A and B (assuming each view has at least one @Environment property)? Possible Alternative If all views are indeed invalidated by environment writes, would it be more efficient to “wrap” frequently-changing values inside an @Observable object instead of updating the environment directly? // Pseudocode @Observable final class SelectedTab { var index: Int } ContentView() .environment(\.selectedTab, selectedTab) struct TabView: View { @Environment(\.selectedTab) private var selectedTab var body: some View { Button("Action") { // Would this avoid invalidating all views using the environment? selectedTab.index = 1 } } } Summary From what I understand, it sounds like the environment should primarily be used for stable, long-lived objects—not for rapidly changing values—since writes might cause far more view invalidations than most developers realize. Is that an accurate interpretation? Follow-Up In Xcode 26 / Instruments, is there a way to monitor writes to @Environment?

The new Virtualization framework (and sample code!) are great. It's a lot of fun to run the sample code and quickly fire up multiple VMs of macOS running as a guest. However, the inability to authenticate with any iCloud services is a significant roadblock. Xcode, for example, is not allowing me to authenticate my developer account. Are there any plans to resolve this issue so that iCloud accounts can be authenticated from within a VM?