Hi everyone, I am developing a .NET MAUI Mac Catalyst app (sandboxed) that communicates with a custom vendor-specific HID USB device. Within the Catalyst app, I am using a native iOS library (built with Objective-C and IOKit) and calling into it via P/Invoke from C#. The HID communication layer relies on IOHIDManager and IOUSBInterface APIs. The device is correctly detected and opened using IOHIDManager APIs. However, IOHIDDeviceRegisterInputReportCallback never triggers — I don’t receive any input reports. To investigate, I also tried using low-level IOKit USB APIs via P/Invoke from my Catalyst app, calling into a native iOS library. When attempting to open the USB interface using IOUSBInterfaceOpen() or IOUSBInterfaceOpenSeize(), both calls fail with: kIOReturnNotPermitted (0xe00002e2). — indicating an access denied error, even though the device enumerates and opens successfully. Interestingly, when I call IOHIDDeviceSetReport(), it returns status = 0, meaning I can successfully send feature reports to the device. Only input reports (via the InputReportCallback) fail to arrive. I’ve confirmed this is not a device issue — the same hardware and protocol work perfectly under Windows using the HIDSharp library, where both input and output reports function correctly. What I’ve verified •Disabling sandboxing doesn’t change the behavior. •The device uses a vendor-specific usage page (not a standard HID like keyboard/mouse). •Enumeration, open, and SetReport all succeed — only reading input reports fails. •Tried polling queues, in queues Input_Misc element failed to add to the queues. •Tried getting report in a loop but no use.

Sidebars for mac Catalyst apps running with UIDesignRequiresCompatibility flag render their active items with a white bg tint – resulting in labels and icons being not visible. mac OS Tahoe 26.1 Beta 3 (25B5062e) FB20765036 Example (Apple Developer App):

On Mac Catalyst 26, a Button bar item in a bottom toolbar look squished. This happens only when the "Mac Catalyst Interface" option is set to "Optimize for Mac". When it is set to "Scale to match iPad", the buttons look fine. For example, in the screenshots below, the text button should say "Press Me", instead of "…" A simple reproducible snippet and a screenshot below. The toolbar button comparison between "Scale to match iPad" and "Optimize for Mac" are shown. Optimize for Mac Scale to match iPad import SwiftUI struct ContentView: View { @State private var selectedItem: String? = "Item 1" let items = ["Item 1", "Item 2"] var body: some View { NavigationSplitView { List(items, id: \.self, selection: $selectedItem) { item in Text(item) } .navigationTitle("Items") } detail: { if let selectedItem = selectedItem { Text("Detail view for \(selectedItem)") .toolbar { ToolbarItemGroup(placement: .bottomBar) { Text("Hello world") Spacer() Button("Press Me") { } Spacer() Button { } label: { Image(systemName: "plus") .imageScale(.large) } } } } else { Text("Select an item") } } } }

There is a serious usability issue with PHPickerViewController in a UIKit app running on macOS 26 via Mac Catalyst when the Mac Catalyst interface is set to “Scaled to Match iPad”. Mouse click and other pointer interactions do not take place in the correct position. This means you have to click in the wrong position to select a photo and to close the picker. This basically makes it unusable. To demonstrate, use Xcode 26 on macOS 26 to create a new iOS app project based on Swift/Storyboard. Then update ViewController.swift with the following code: import UIKit import PhotosUI class ViewController: UIViewController { override func viewDidLoad() { super.viewDidLoad() var cfg = UIButton.Configuration.plain() cfg.title = "Photo Picker" let button = UIButton(configuration: cfg, primaryAction: UIAction(handler: { _ in self.showPicker() })) button.translatesAutoresizingMaskIntoConstraints = false view.addSubview(button) NSLayoutConstraint.activate([ button.centerXAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerXAnchor), button.centerYAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerYAnchor), ]) } private func showPicker() { var config = PHPickerConfiguration() config.selectionLimit = 10 config.selection = .ordered let vc = PHPickerViewController(configuration: config) vc.delegate = self self.present(vc, animated: true) } } extension ViewController: PHPickerViewControllerDelegate { func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) { print("Picked \(results.count) photos") dismiss(animated: true) } } Then go to the "Supported Destinations" section of the project target. Add a "Mac (Mac Catalyst)" destination. Then under the "Deployment Information" section, make sure the "Mac Catalyst Interface" setting is "Scaled to Match iPad". Then build and run the app on a Mac (using the Mac Catalyst destination) with macOS 26.0.1. Make sure the Mac has a dozen or so pictures in the Photo Library to fully demonstrate the issue. When the app is run, a simple screen appears with one button in the middle. Click the button to bring up the PHPickerViewController. Now try to interact with the picker interface. Note that all pointer interactions are in the wrong place on the screen. This makes it nearly impossible to choose the correct photos and close the picker. Quit the app. Select the project and go to the General tab. In the "Deployment Info" change the “Mac Catalyst Interface” setting to “Optimize for Mac” and run the app again. Now the photo picker works just fine. If you run the app on a Mac running macOS 15 then the photo picker works just fine with either “Mac Catalyst Interface” setting. The problem only happens under macOS 26.0 (I do not have macOS 26.1 beta to test) when the “Mac Catalyst Interface” setting is set to “Scaled to Match iPad”. This is critical for my app. I cannot use “Optimize for Mac”. There are far too many issues with that setting (I use UIStepper and UIPickerView to start). So it is critical to the usability of my app under macOS 26 that this issue be resolved. It is expected that PHPickerViewController responds correctly to pointer events on macOS 26 when running a Mac Catalyst app set to “Scaled to Match iPad”. A version of this has been filed as FB20503207

struct ContentView: View { @State private var showingPopover:Bool = false private var popOverHeight: CGFloat { return 566 } var body: some View { NavigationStack { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundStyle(.tint) Text("Hello, world!") } .padding() .toolbar { ToolbarItem(placement: .topBarTrailing) { Button { showingPopover = true } label: { Image(systemName: "plus") .font(Font.system(size: 15)) .foregroundColor(Color.red) } .popover(isPresented: $showingPopover) { FTShelfNewNotePopoverView1() .frame(minWidth: 340.0) .frame(height: popOverHeight) } } } } } }

Hello, creating a simple-as-it-gets Slider in SwiftUI and then running that app on Mac Catalyst with the macOS idiom enabled, the app crashes: struct ContentView: View { @State private var sliderValue: Double = 0.4 var body: some View { VStack { Slider(value: $sliderValue) } .padding() } } running this will result in an exception: _setMinimumEnabledValue: is not supported on UISlider when running Catalyst apps in the Mac idiom. See UIBehavioralStyle for possible alternatives. This is obviously not ideal and also apparently no documented. Is there a workaround for this? It used to work for on macOS Sonoma. macOS 26 RC Xcode 26 RC FB20191635 Thanks!

Hi everyone, I’m testing my Catalyst SwiftUI project on iOS 26 / iPadOS 26 / macOS 26. I started with a NavigationSplitView (triple-column) inside a WindowGroup. On iPad it looks great: the toolbar items merge into the navigation bar, with the three traffic lights. But on Mac Catalyst, the app always reserves a blank safe area below the traffic lights, and places the toolbar on a separate line beneath the title bar. That leaves wasted vertical space I don’t want. What I expect (based on Apple’s WWDC session “Elevate the design of your iPad app”): The toolbar should merge into the title bar with the traffic lights, no separate row. Content should extend into the full height of the window. What I get on Mac Catalyst: Title bar + traffic lights at the top. Then a completely separate toolbar row below it. Safe area inset prevents my content from reaching the top of the window. What I’ve tried: .toolbarRole(.automatic), .editor, .browser → no effect. Hiding the title bar via titlebar?.titleVisibility = .hidden → removes the text but not the toolbar gap. Clearing titlebar?.toolbar → no difference. So far, I can’t find any way to get Catalyst to integrate toolbars into the window chrome the way native SwiftUI on macOS does. Is this a known limitation of Mac Catalyst, or is there a supported way to achieve the same “inline toolbar with window controls” layout? Switching to a Mac app vs. Catalyst fixes the issue, but I would have a lot more work to do to get the app ready for release, not ideal since it works near perfect on iPad. Thanks!

My UIKit/Mac Catalyst app supports a user opening multiple windows (multiple scenes). One of these is a special scene that shows content that I want to appear in front of all other app windows/scenes, even while the user is interacting with one of the app's other scenes. I do not need this special scene to stay in front of the windows of other apps, just in front of the windows of my own app. While I'm not 100% sure, it seems that AppKit supports this through the NSWindow level property. I can't find any equivalent feature in UIKit/Mac Catalyst. UIWindow windowLevel is not the same thing since that only affects the order of windows within a given scene. I need an entire scene (and its windows) to stay in front of my app's other scenes (and their windows). I don't see anything relevant in UIWindow, UIScene, UIWindowScene, UISceneSession, UIScene.ActivationRequestOptions, or UIWindowScene.ActivationRequestOptions.

I have a Catalyst app that uses popovers frequently, and I'd love to have them stay active when the app loses focus. It appears this is controlled in a native AppKit app via NSPopover.Behavior. Is this functionality exposed somewhere in Catalyst?

I have a Catalyst app on the App Store and I'm starting to get messages from users that the popover bubbles all over the app are without content. I see the error locally as well, but I don't know how to fix it. I get the following warning in XCode when opening a popup: UIScene property of UINSSceneViewController was accessed before it was set.

I have a SwiftUI Mac Catalyst app that shows a video player using a UIViewControllerRepresentable AVPlayerViewController. When I tap the full screen button on the native playback control, the app crashes. The app crashes only when built with Xcode 26. When I build with Xcode 16, this does not cause a crash. Here is some of the crash log: 0 CoreFoundation 0x000000019a5cc770 __exceptionPreprocess + 176 1 libobjc.A.dylib 0x000000019a0aa418 objc_exception_throw + 88 2 CoreFoundation 0x000000019a69b7fc -[NSException initWithCoder:] + 0 3 AppKit 0x000000019eeee1d0 -[NSBezierPath(NSBezierPathDevicePrimitives) _deviceMoveToPoint:] + 104 4 AppKit 0x000000019eeec930 -[NSBezierPath appendBezierPathWithRoundedRect:xRadius:yRadius:] + 200 5 AppKit 0x000000019eeea238 +[NSBezierPath bezierPathWithRoundedRect:xRadius:yRadius:] + 88 6 AVKitMacHelper 0x0000000247d73cc4 -[AVScrubberSliderCell drawBarInside:flipped:] + 1264 7 AppKit 0x000000019f35cf7c -[NSSliderCell drawInteriorWithFrame:inView:] + 680 8 AppKit 0x000000019f35ccbc -[NSSliderCell drawWithFrame:inView:] + 104 Any ideas!?

I've got a Catalyst app that exposes some custom context menu items via the buildMenu API. When it runs on Tahoe, there's some weirdness with how the images in the menu items are sized. See attached screenshot below. The three items on the bottom are using SF Symbols for their images, and the rest are using custom images from an asset catalog. Is this a bug in Tahoe 26.0? Or should I be resizing my images before giving them to UIAction? If the latter, what should the size be, and is this documented somewhere or available from an API?

I have a SwiftUI Mac Catalyst app. I create a toolbar like this NavigationSplitView(columnVisibility: $sceneModel.columnVisibility, preferredCompactColumn: $preferredColumn) { sidebarView() } detail: { contentView() .toolbar { ToolbarItemGroup(placement: .topBarTrailing) { HStack { Button { sceneModel.onMaps(sender: self) } label: { Image(systemName: "map") .font(.title2) } Button { sceneModel.onSearch(sender: self) } label: { Image(systemName: "magnifyingglass") .font(.title2) } ... } } } } When my Mac Appearance is set to dark mode and the content under the toolbar is dark the toolbar looks good like this. But then if I have light content under the toolbar, the glass effect changes to light, but the tint on the icons stays white instead of changing to black and it is hard to see the icon. It looks like this. When I set the Appearance on my Mac to light, then the toolbar works just fine on both dark and light colored backgrounds. Does anyone know how I can fix this when the appearance is Dark?

My Mac Catalyst app fails with a "MissingEntitlement" error when accessing keychain/secure storage, while the same code works perfectly on iOS. I have tested this extensively on macOS using Visual Studio Code on a MacBook, trying both automatic and manual provisioning approaches - both result in the same MissingEntitlement error during keychain operations. Error Message: "An error occurred during OTP verification: Error adding record: MissingEntitlement" Environment : Platform: Mac Catalyst (.NET 9.0) Issue: Keychain access fails on macOS, works on iOS Development: Using .NET MAUI What I've Tried : Entitlements Configuration Added keychain-access-groups to Entitlements.plist: xml <key>keychain-access-groups</key> <array> <string>$(AppIdentifierPrefix)com.example.myapp</string> </array> Project Signing Setup (.csproj configuration) : <PropertyGroup Condition="'$(TargetFramework)'=='net9.0-maccatalyst'"> <EnableCodeSigning>true</EnableCodeSigning> <ProvisioningType>manual</ProvisioningType> <DevelopmentTeam>TEAM_ID</DevelopmentTeam> <CodesignKey>Apple Development: Name (XXXXXXXXXX)</CodesignKey> <ProvisioningProfile>PROVISIONING_PROFILE_UUID</ProvisioningProfile> <CodesignEntitlements>Platforms/MacCatalyst/Entitlements.plist</CodesignEntitlements> <UseHardenedRuntime>true</UseHardenedRuntime> </PropertyGroup> Has anyone encountered similar issues with Mac Catalyst keychain access? Any insights on proper entitlement configuration would be greatly appreciated!

Hi everyone, I’ve encountered an issue where using a popover inside the toolbar of a Catalyst app causes a crash on macOS 26 beta 5 with Xcode 26 beta 5. Here’s a simplified code snippet: import SwiftUI struct ContentView: View { @State private var isPresentingPopover = false var body: some View { NavigationStack { VStack { } .padding() .toolbar { ToolbarItem { Button(action: { isPresentingPopover.toggle() }) { Image(systemName: "bubble") } .popover(isPresented: $isPresentingPopover) { Text("Hello") .font(.largeTitle) .padding() } } } } } } Steps to reproduce: Create a new iOS app using Xcode 26 beta 5. Enable Mac Catalyst (Match iPad). Add the above code to show a Popover from a toolbar button. Run the app on macOS 26, then click the toolbar button. The app crashes immediately upon clicking the toolbar button. Has anyone else run into this? Any workarounds or suggestions would be appreciated! Thanks!

Hi, I have a NSToolbar in my Mac Catalyst app with a space and flexible space item in it (https://developer.apple.com/documentation/appkit/nstoolbaritem/identifier/space). On macOS Tahoe the space item is being rendered with a Liquid Glass effect and seems to be automatically grouped with the previous item. Is there a way to prevent this? It basically adds some undesired padding next to the previous item and looks add. The flexible space is rendered normally and as before. I am talking about the space right next to the back chevron item. Thanks for any hints!

Hi everyone! I've encountered an issue when using Sheet + ScrollView on Mac Catalyst: the buttons in the toolbar appear with an abnormal gray color. import SwiftUI struct ContentView: View { var body: some View { VStack { } .sheet(isPresented: .constant(true)) { Sheet() } } } struct Sheet: View { var body: some View { NavigationStack { ScrollView { // <-- no issue if use List } .toolbar { Button(action: {}) { // <-- 👀 weird gray color Image(systemName: "checkmark") } } } } } Steps to Reproduce: On macOS 26.0 beta 9, use Xcode 26.0 beta 7 to create an iOS project and enable Mac Catalyst. Paste the code above. Select the Mac Catalyst scheme and run the project. The buttons in the toolbar show a strange gray appearance. If you change the ScrollView to a List in the code, the issue does not occur. FB20120285

On macOS 15.2, any Mac Catalyst project that does not support portrait iPad orientation will no longer be able to successfully show the contents of any popover controls. This does not appear to be a problem on earlier versions of macOS and it only affects Mac Catalyst builds, not "Designed for iPad" builds. STEPS TO REPRODUCE Create a project that utilizes Mac Catalyst. Create a simple button that shows a popover with simple content. Remove Portrait as a supported orientation. Run the project on macOS 15.2 as a Mac Catalyst build. Note that the content inside the popover is not shown the popover is shown. Run the project as Designed for iPad. Note that the popover content shows correctly.

Hi everyone! I've encountered an issue on Mac Catalyst: using the latest inspector modifier causes abnormal Sidebar and Columns state in NavigationSplitView. Sample Code: struct ContentView: View { @State private var isPresented = false var body: some View { NavigationSplitView { List { ForEach(0..<20, id: \.self) { item in Text("Item \(item)") } } } content: { List { ForEach(0..<20, id: \.self) { item in Text("Item \(item)") } } } detail: { List { } } .inspector(isPresented: $isPresented) { Form { } } } } Steps to reproduce: Xcode 16 beta 7, create a new iOS project Paste the code above Enable Mac Catalyst Run on Mac (macOS 15 beta 9) Press Command+N three times to open 3 new windows Click the Sidebar Toggle button The issue occurs (see screenshot below) Through testing, I found that as long as the inspector modifier is attached, the issue occurs. Also, the problem only appears in the 3rd and subsequent newly opened windows—the first two windows work as expected. FB20061521

We are using a column style split view controller as root view of our app and in iOS26 the navigation titles of primary and supplementary view controllers are not visible and secondary view controller title is displayed in supplementary column. Looks the split view hidden all the child view controllers title and shown the secondary view title as global in macCatlayst. The right and left barbutton items are showing properly for individual view controllers. Facing this weird issue in iOS26 betas. The secondary navigation title also visible only when WindowScene,titlebar.titleVisibility is not hidden. Kindly suggest the fix for this issue as we can't use the secondary view navigation title for showing supplementary view's data. The issue not arises in old style split views or when the split view embedded in another splitView. Refer the sample code and attachment here let splitView = UISplitViewController(style: .tripleColumn) splitView.preferredDisplayMode = .twoBesideSecondary splitView.setViewController(SplitViewChildVc(title: "Primary"), for: .primary) splitView.setViewController(SplitViewChildVc(title: "Supplementary"), for: .supplementary) splitView.setViewController(SplitViewChildVc(title: "Secondary"), for: .secondary) class SplitViewChildVc: UIViewController { let viewTitle: String init(title: String = "Default") { self.viewTitle = title super.init(nibName: nil, bundle: nil) } override func viewDidLoad() { super.viewDidLoad() self.title = viewTitle self.navigationItem.title = viewTitle if #available(iOS 26.0, *) { navigationItem.subtitle = "Subtitle" } let leftbutton = UIBarButtonItem(barButtonSystemItem: .cancel, target: nil, action: nil) navigationItem.leftBarButtonItem = leftbutton let rightbutton = UIBarButtonItem(barButtonSystemItem: .add, target: nil, action: nil) navigationItem.rightBarButtonItem = rightbutton } }