John Brayton:

NSTrackingSeparatorToolbarItem adds a white band over the top of the leading split view panes when in full screen mode on macOS 27 [beta 3]. That white band appears to have the height of the toolbar.

He says this was fixed in Beta 4.

John Brayton:

macOS 27 developer beta 5 (26A5406e) introduces a bug that causes a white bar to appear over window content if the window’s toolbar has an NSTrackingSeparatorToolbarItem. I filed FB24266969 with Apple describing this.

Steve Troughton-Smith:

NSSearchToolbarItem has been screwed last minute in Catalyst with less than a month to go? Cool, cool…

That’s the kind of thing that can halt my release plans entirely 🫠

Ron Elemans:

Also screwed up in AppKit, with the macOS 27 beta 5 release.

Also, the titlebarSeparatorStyle setting seems to be ignored. Toolbars in beta 5 always have a separator line and a blurred slightly lighter background.

Weirdly enough Apple’s own apps don’t have these issues.

John Brayton:

In macOS 27 developer beta 5, search fields in toolbars (NSSearchToolbarItem instances) have their placeholder text, search strings, and magnifying glass icons vertically off-center. I reported this as FB24286690.

Mario Guzmán:

Beta 6 also fixes the UI issues with NSSearchToolbarItem. Elements are now re-aligned again, the recents menu is in a good position, and the focus ring is perfectly outlining the entire bounds. :D

Previously:

• SwiftUI Toolbars
• macOS 27 Public Beta

CrashReportExtension:

The Crash Report Extension framework allows you to perform analysis and produce a report when your app crashes. Your crash-handling code executes out-of-process, rather than from a signal handler or other in-process techniques.

You implement your handler by writing an app extension that conforms to the CrashReporterExtension protocol. The system calls your processCrashReport(process:) method when the app crashes. Use the CrashedProcess parameter to inspect the state of the crashed app by retrieving a crash reason, symbolicating relevant addresses, and communicating with the process over a read-only Mach port. After collecting the crash data, you can send a report back to your own server.

[…]

Crash Report Extension is available on iOS 27 and later. It isn’t available to Catalyst-based macOS apps, or on iOS apps running on Mac computers with Apple silicon.

The top of the page says “macOS 27.0+,” so I guess this means it does work for regular AppKit and SwiftUI Mac apps. It’s great to finally have a supported way to do this.

I don’t know why they can’t just give you the crash report text or .ips JSON directly, though. It looks like you have to use Mach IPC with the corpsePort to get the backtrace for each thread and then use the extension API to symbolicate the addresses. Even then, I’m not sure you can get all the information that’s in a standard crash report, such as the Application Specific Backtrace. Maybe you can find the address for gCRAnnotations/__crashreporter_info__ and load it with mach_vm_read?

Previously:

• WWDC 2026 Links
• Visual Studio App Center Retirement
• What Happened to __crashreporter_info__?
• Restarting macOS Apps Automatically on Crash
• Crash Reporting for Sandboxed Mac Apps
• Reliable Crash Reporting

iOS & iPadOS 27 Beta Release Notes:

[You] can use UIScene.extendStateRestoration and UIScene.completeStateRestoration to extend state restoration for UIScene.ActivationState.background to UIScene.ActivationState.foreground lifecycle transitions.

[…]

iOS and iPadOS apps built with the 27.0 SDK or later are required to include a launch screen.

[…]

Siri can load resources from drag interactions installed in your app’s interface.

[…]

In apps built with the iOS 27.0 SDK, a presented view controller inherits its trait collection by walking up its view’s superview chain through the intermediate views of the presentation, rather than jumping directly to the presentation controller.

UIKit updates:

Use UICollectionViewCompositionalLayoutSectionProvider closures as part of automatic observation tracking to automatically invalidate and update compositional layouts when observable objects change.

[…]

Use UIRefreshControl and UIStepper in Mac apps built with Mac Catalyst. These controls are now fully supported in the Mac idiom.

[…]

Starting in iOS 27, apps built with the latest SDK must use the scene-based life cycle or they fail to launch.

[…]

Use NSTextTable, NSTextBlock, and NSTextTableBlock to represent table structures in attributed strings.

Modernize your UIKit app:

Discover the latest updates to UIKit. Learn how to update your iPhone app layouts to work great when resized with iPhone Mirroring and on iPad. Explore new APIs for tab and navigation bars, find out how to prepare your app for new Apple Intelligence capabilities, and get introduced to a skill for your coding agent of choice that helps modernize your codebase.

Kyle Howells:

iOS 27’s UIKit is a tiny release in terms of API changes, but does have some changes. There are no new top-level paradigms, but there’s an new addition to TextKit 2, a new scene accessory API, Liquid-Glass-era bar minimization controls, and a small amount of quality-of-life additions to menus, tab bars, and drag interactions.

Hartley Charlton:

Apple appears to be laying the groundwork for a foldable iPhone in iOS 27, with new references discovered in the operating system’s frameworks and a notable emphasis on flexible app layouts at this year’s Platforms State of the Union.

Jordan Morgan:

The nav bar and its friends got quite a bit of attention, and to be honest that’s where we will find most of the changes. They adapt to all sorts of sizes and situations…hmmm, I WONDER WHY!?

[…]

A few years ago, I wondered if UIKit would be deprecated altogether. That would’ve been drastic, sure, but I did wonder. These days, I don’t share the same concern anymore. SwiftUI gets better each year, and yeah — it’ll have top billing. But UIKit is solid, and it appears to be a core part of Apple’s strategy into the future.

Not much changed this year, and not much was added that’s flashy. But, that’s true of iOS 27 in several ways.

Previously:

• UIKit in iOS 26
• WWDC 2026 Links