In my app, I use api provided in Photos framework to delete specified photo.
But after upgrading to iOS 26, the delete function in some iOS device no longer work.
The api will never triggers the system confirmation dialog, and the completionHandler is never called.
In the iOS Photos app, deletion works correctly on the same assets, but calling the API from my app does not work.
Steps to Reproduce
Make sure the app has Full Photo Library Access.
Execute the following code:
PHPhotoLibrary.shared().performChanges({
let assetsToBeDeleted = PHAsset.fetchAssets(withLocalIdentifiers: delUrls, options: nil)
PHAssetChangeRequest.deleteAssets(assetsToBeDeleted)
}, completionHandler: completionHandler)
Expected Behavior
The system should present a confirmation dialog asking the user to delete the selected photos.
After the user confirms, the deletion should occur, and the completionHandler should be called with success or error.
Actual Behavior
The system delete confirmation dialog does not appear.
The completionHandler is never called.
Environment
iOS Versions: 26.1 / 26.0.1
It looks like api bug.
I want to check Is it a know issue and will be fixed. Thanks
Photos & Camera
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The introduction of PHBackgroundResourceUploadExtension is a welcome addition in iOS 26.1. I wonder however, how to attach a debugger and actually get the system to call the process() method of the extension. I tried to run the extension both inside photos app (and also the main app for testing), but when I take a photo or add photos to the library (saving), the process() method does never get called. Any hints would be appreciated to debug the PHBackgroundResourceUploadExtension during development.
I'm adopting Liquid Glass in iOS 26, when I try to test VNDocumentCameraViewController with document scanning after Liquid Glass enabled, there's a crash just after a photo is taken in VNDocumentCameraViewController, here's the screenshot when it crashed
The exception output in XCode console is this:
*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Layout requested for visible navigation bar, <UINavigationBar: 0x1240bde00; frame = (0 117; 390 54); opaque = NO; tintColor = UIExtendedSRGBColorSpace 1 1 0 1; layer = <CALayer: 0x120c21e60>> standardAppearance=0x12407b900 scrollEdgeAppearance=0x12407bb80 compactAppearance=0x12407b880 no-scroll-edge-support, when the top item belongs to a different navigation bar. topItem = <UINavigationItem: 0x1240bd800> style=navigator leftBarButtonItems=0x123d4e5f0 rightBarButtonItems=0x123d4d5a0, navigation bar = <UINavigationBar: 0x107b9ad00; frame = (0 47; 390 54); opaque = NO; autoresize = W; tintColor = UIExtendedSRGBColorSpace 1 1 0 1; layer = <CALayer: 0x120c20150>> delegate=0x10a805200 standardAppearance=0x107b2c300 scrollEdgeAppearance=0x107b2c280 compactAppearance=0x107b2c100, possibly from a client attempt to nest wrapped navigation controllers.'
*** First throw call stack:
(0x18e1db994 0x18b0f5814 0x18c092aa0 0x193b18660 0x193a7d540 0x193a7e020 0x1953ec4a0 0x1943b7d78 0x18ed83420 0x18ed82f74 0x18eb83134 0x18eb44c10 0x18eb70bc4 0x18eb7e74c 0x193ac8cd0 0x193ac8c04 0x193ad6afc 0x193ad5f8c 0x27b456560 0x18e12c4cc 0x18e15c0b0 0x18e15bfd8 0x18e133c1c 0x18e132a6c 0x22ed54498 0x193af6ba4 0x193a9fa78 0x193bcb68c 0x102cc2718 0x102cc2688 0x102cc2794 0x18b14ae28)
libc++abi: terminating due to uncaught exception of type NSException
Hello,
I have an iOS camera app that captures exposure brackets and performs custom HDR processing.
On iOS 26, I’m observing a visual difference between:
a single photo captured at –2 EV, and the –2 EV frame from an exposure bracket (–2 / 0 / +2 EV).
On iOS 26:
The single –2 EV image looks natural and consistent.
The –2 EV image from the bracket appears clamped / distorted, most noticeably in high dynamic range scenes (highlight compression and loss of detail).
On iOS 18, both approaches produce visually identical and correct –2 EV images.
The issue only appears for bracketed captures on iOS 26.
Attachments (examples)
iOS 26
Single capture –2 EV (JPEG):
/Users/danilobudimir/Downloads/ios26SingleImage/JPEG image-4006-8B77-51-0.jpeg
Single capture –2 EV — Capture report (dumped settings):
/Users/danilobudimir/Downloads/ios26SingleImage/UnderExposureDebug_CaptureReport_2026-01-09T15-59-20Z.md
Bracket capture –2 EV frame (JPEG):
/Users/danilobudimir/Downloads/bracket_iOS26/JPEG image-45CE-9793-A5-0.jpeg
Bracket capture — Capture report (dumped settings):
/Users/danilobudimir/Downloads/bracket_iOS26/UnderExposureDebug_CaptureReport_2026-01-09T15-55-42Z.md
iOS 18
Single capture –2 EV (JPEG):
/Users/danilobudimir/Downloads/ios18SingleImage/JPEG image-47FD-AF73-28-0.jpeg
Single capture –2 EV — Capture report:
/Users/danilobudimir/Downloads/ios18SingleImage/UnderExposureDebug_CaptureReport_2026-01-09T16-25-27Z.md
Bracket capture — –2 EV frame (JPEG):
/Users/danilobudimir/Downloads/bracket_iOS18/JPEG image-4A4C-9E93-46-0.jpeg
Bracket capture — Capture report:
/Users/danilobudimir/Downloads/bracket_iOS18/UnderExposureDebug_CaptureReport_2026-01-09T16-27-23Z.md
Question
Is there any new behavior in iOS 26 AVFoundation related to:
AVCapturePhotoBracketSettings,
tone mapping / HDR preprocessing,
or internal image processing applied specifically to bracketed frames?
Is there a new flag, format requirement or opt-out mechanism required to preserve linear underexposed frames in exposure brackets?
I'm developing iPad app that will be mostly dedicated for certain external camera for visually impaired people.
The linux UVC api (e.g. using guvcview) allows to enable automatic exposure for the camera. IOs api "isExposureModeSupported" unfortunately returns false for any of the exposure modes.
Is it a bug? Or perhaps AVFoundation doesn't support UVC exposure yet?
I’ve never had a problem with any update before but as soon as I updated to 18.3 update my camera decided to start blurring when it’s in 1x & 2x, I use my camera daily for work and this is unacceptable. I’m wondering if anyone else is having this issue, it’s really frustrating..
I'm creating an app that uses AVCaptureSession to pass camera input to AVCaptureMetadataOutput type set [metaout setMetadataObjectTypes:@[AVMetadataObjectTypeFace]] and scan Face.
After updating to OS 26 Beta2 and iOS 26 Beta2, an issue has occurred where the delegate method of AVCaptureMetadataOutputObjectsDelegate is not called on some devices. The following devices are experiencing this issue.
iPad (9th Gen)
iPad air (4th Gen)
iPhone 15
This issue has not occur on any other devices I have.
I tried running the AVFoundation sample code on the Apple Developer site on the above device. The same problem still occurs. https://developer.apple.com/documentation/avfoundation/capture_setup/avcambarcode_detecting_barcodes_and_faces
Are any additional settings required after OS 26 beta and iOS 26 beta? Or is there some problem on the OS side?
PLATFORM AND VERSION :iOS 18.5
I wanted to bring to your attention a critical issue some of our production users are experiencing with the CoinOut app. Specifically, users are encountering a problem when attempting to capture photos of receipts using the app's customized camera feature. The camera, which utilizes AVCaptureVideoPreviewLayer and AVCaptureDevice, occasionally fails to load the preview, resulting in a black screen instead of the expected camera view.
This camera blackout issue is significantly impacting the user experience as it prevents them from snapping photos of their receipts, which is a core functionality of the CoinOut app.
Any help/suggestion to this issue would be greatly appreciated.
STEPS TO REPRODUCE
Open the app and click on camera icon.
It will display camera to capture photo.
Camera shows black for few production user's.
class ViewController: UIViewController {
@IBOutlet private weak var captureButton: UIButton!
private var fillLayer: CAShapeLayer!
private var previewLayer : AVCaptureVideoPreviewLayer!
private var output: AVCapturePhotoOutput!
private var device: AVCaptureDevice!
private var session : AVCaptureSession!
private var highResolutionEnabled: Bool = false
private let sessionQueue = DispatchQueue(label: "session queue")
override func viewDidLoad() {
super.viewDidLoad()
setupCamera()
customiseUI()
}
@IBAction func startCamera(sender: UIButton) {
didTapTakePhoto()
}
private func setupCamera() {
let session = AVCaptureSession()
session.sessionPreset = AVCaptureSession.Preset.high
previewLayer = AVCaptureVideoPreviewLayer(session: session)
output = AVCapturePhotoOutput()
device = AVCaptureDevice.default(.builtInWideAngleCamera, for: AVMediaType.video, position: .back)
if let device = self.device{
do{
let input = try AVCaptureDeviceInput(device: device)
if session.canAddInput(input){ session.addInput(input)}
else { print("\(#fileID):\(#function):\(#line) : Session Input addition failed") }
if session.canAddOutput(output){
output.isHighResolutionCaptureEnabled = self.highResolutionEnabled
session.addOutput(output)
} else { print("\(#fileID):\(#function):\(#line) : Session Input high resolution failed") }
previewLayer.videoGravity = .resizeAspectFill
previewLayer.session = session
sessionQueue.async { session.startRunning() }
self.session = session
self.session.accessibilityElementIsFocused()
try device.lockForConfiguration()
if device.isWhiteBalanceModeSupported(AVCaptureDevice.WhiteBalanceMode.autoWhiteBalance) {
device.whiteBalanceMode = .autoWhiteBalance
} else { print("\(#fileID):\(#function):\(#line) : isWhiteBalanceModeSupported no supported") }
if device.isWhiteBalanceModeSupported(AVCaptureDevice.WhiteBalanceMode.continuousAutoWhiteBalance) {
device.whiteBalanceMode = .continuousAutoWhiteBalance
} else { print("\(#fileID):\(#function):\(#line) : isWhiteBalanceModeSupported no supported") }
if device.isFocusModeSupported(.continuousAutoFocus) { device.focusMode = .continuousAutoFocus}
else if device.isFocusModeSupported(.autoFocus) { device.focusMode = .autoFocus }
device.unlockForConfiguration()
} catch { print("\(#fileID):\(#function):\(#line) : \(error.localizedDescription)") }
} else { print("\(#fileID):\(#function):\(#line) : Device found as nil") }
}
private func customiseUI() {
let path = UIBezierPath(roundedRect: CGRect(x: 0, y: 0, width: self.view.bounds.width, height: self.view.bounds.height), cornerRadius: 0)
let rectangleWidth = view.frame.width - (view.frame.width * 0.16)
let x = (view.frame.width - rectangleWidth) / 2
let rectangleHeight = view.frame.height - (view.frame.height * 0.16)
let y = (view.frame.height - rectangleHeight) / 2
let roundRect = UIBezierPath(roundedRect: CGRect(x: x, y: y, width: rectangleWidth, height: rectangleHeight), byRoundingCorners:.allCorners, cornerRadii: CGSize(width: 0, height: 0))
roundRect.move(to: CGPoint(x: self.view.center.x , y: self.view.center.y))
path.append(roundRect)
path.usesEvenOddFillRule = true
fillLayer = CAShapeLayer()
fillLayer.path = path.cgPath
fillLayer.fillRule = .evenOdd
fillLayer.opacity = 0.4
previewLayer.addSublayer(fillLayer)
previewLayer.frame = view.bounds
view.layer.addSublayer(previewLayer)
view.bringSubviewToFront(captureButton)
}
private func didTapTakePhoto() {
let settings = self.getSettings(camera: self.device)
if device.isAdjustingFocus {
do {
try device.lockForConfiguration()
device.focusMode = .continuousAutoFocus
device.unlockForConfiguration()
device.addObserver(self, forKeyPath: "adjustingFocus", options: [.new], context: nil)
} catch { print(error) }
} else { output.capturePhoto(with: settings, delegate: self) }
}
func getSettings(camera: AVCaptureDevice) -> AVCapturePhotoSettings {
var settings = AVCapturePhotoSettings()
if let rawFormat = output.availableRawPhotoPixelFormatTypes.first {
settings = AVCapturePhotoSettings(rawPixelFormatType: OSType(rawFormat))
}
settings.isHighResolutionPhotoEnabled = self.highResolutionEnabled
let previewPixelType = settings.availablePreviewPhotoPixelFormatTypes.first!
let previewFormat = [kCVPixelBufferPixelFormatTypeKey as String: previewPixelType] as [String : Any]
settings.previewPhotoFormat = previewFormat
return settings
}
}
extension ViewController: AVCapturePhotoCaptureDelegate {
func photoOutput(_ output: AVCapturePhotoOutput, willCapturePhotoFor resolvedSettings: AVCaptureResolvedPhotoSettings) {
AudioServicesDisposeSystemSoundID(1108)
}
func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {
guard let data = photo.fileDataRepresentation() else { return }
let image = UIImage(data: data)!
showImage(cropped: image)
}
func showImage(cropped: UIImage) {
let vc = self.storyboard?.instantiateViewController(withIdentifier: "ImagePreviewViewController") as? ImagePreviewViewController
vc?.captured = cropped
self.present(vc!, animated: true)
}
}```
Hi,
I’m trying to implement the new PhotoKit PHBackgroundResourceUploadExtension. I created the extension, enabled full photo library access in the host app, and registered the extension point using the string: com.apple.photos.background-upload.
However, when I attempted to enable the extension with:
try library.setUploadJobExtensionEnabled(true)
I received the following error:
Error Domain=PHPhotosErrorDomain Code=-1 "(null)"
This happens when running the app on Xcode 26.1 and 26.2 Beta, using the iPhone 17 Pro Max simulator (iOS 26.1 and 26.2).
My question is: Is this extension supported on the simulator?
I’m asking because at the moment it’s difficult for me to test this on a physical device.
Also, What's the meaning of the error?
Thanks.
Hi Apple Developer Forums,
I’m developing an iOS camera app that processes RAW captures using Core Image. I’m seeing a large “first use” performance penalty specifically when creating the CIImage from CIRAWFilter.outputImage.
What’s slow (important detail)
I’m measuring the time for:
let rawFilter = CIRAWFilter(imageData: rawData, identifierHint: hint)
let ciImage = rawFilter.outputImage
This is not CIContext.render(...) / createCGImage(...). It’s just the time to access outputImage (i.e., building the Core Image graph / RAW pipeline setup).
Observed behavior
First time accessing CIRAWFilter.outputImage: ~3 seconds
Second time (same app session, similar RAW): ~3 milliseconds
So something heavy is happening only on first use (decoder initialization, pipeline setup, shader/library compilation, caching, etc.).
Using Metal System Trace, I also noticed that during the slow first call there are many “Create MTLLibrary” events, while the second call doesn’t show this pattern.
Warm-up attempts using bundled DNG
I tried to “warm up” early (e.g., on camera screen entry) by loading a bundled DNG and then accessing CIRAWFilter.outputImage by taking a photo:
Warm-up with a ~247 KB DNG → first real RAW outputImage cost drops to ~1.42s
Warm-up with a ~25 MB DNG → first real RAW outputImage cost drops to ~843ms
This helps, but it’s still far from the steady-state ~3ms.
Warm-up by capturing a real RAW (works, but concerns)
The only method that fully eliminates the delay is to trigger a real RAW capture programmatically before the user’s first photo, then use that captured rawData to warm up the CIRAWFilter.outputImage path. This brings the first user-facing capture close to the steady-state timing.
However:
In some regions, the camera shutter sound cannot be suppressed, so “hidden warm-up capture” is unacceptable UX.
I’m also unsure whether triggering a real capture without an explicit user action could raise compliance/privacy concerns, even if the image is immediately discarded and never saved/uploaded.
Questions
Is the large first-time cost of CIRAWFilter.outputImage expected (RAW pipeline initialization / shader compilation)?
Is there an Apple-recommended way to pre-initialize the Core Image RAW pipeline / Metal resources so the first outputImage is fast, without taking a real photo?
Are there any best practices (e.g. CIContext creation timing, prepareRender(...), specific options) that reliably reduce this first-use overhead for CIRAWFilter?
Attachments
Figure 1: First RAW capture with no warm-up (~3s outputImage time)
Figure 2: First RAW capture after warm-up with bundled DNG (improved but still hundreds of ms)
Thanks for any guidance or experience sharing!
Some users reported that their images are not loading correctly in our app. After a lot of debugging we identified the following:
This only happens when the app is build for Mac Catalyst. Not on iOS, iPadOS, or “real” macOS (AppKit).
The images in question have unusual color spaces. We observed the issue for uRGB and eciRGB v2.
Those images are rendered correctly in Photos and Preview on all platforms.
When displaying the image inside of a UIImageView or in a SwiftUI Image, they render correctly.
The issue only occurs when loading the image via Core Image.
When comparing the different Core Image render graphs between AppKit (working) and Catalyst (faulty) builds, they look identical—except for the result.
Mac (AppKit):
Catalyst:
Something seems to be off when Core Image tries to load an image with foreign color space in Catalyst.
We identified a workaround: By using a CGImageDestination to transcode the image using the kCGImageDestinationOptimizeColorForSharing option, Image I/O will convert the image to sRGB (or similar) and Core Image is able to load the image correctly. However, one potentially loses fidelity this way.
Or might there be a better workaround?
Topic:
Media Technologies
SubTopic:
Photos & Camera
Tags:
Image I/O
Photos and Imaging
Core Image
Core Graphics
I'm using this library: https://github.com/Yummypets/YPImagePicker to capture photos.
I've modified it slightly, and I'm using an older version.
When testing on my iPhone 16e, ios 26, whenever I take a photo, I get the following two error messages:
<<<< FigXPCUtilities >>>> signalled err=-17281 at <>:302
<<<< FigCaptureSourceRemote >>>> Fig assert: "err == 0 " at bail (FigCaptureSourceRemote.m:569) - (err=-17281)
These error messages appear, but as far as I can tell, the photo comes through OK, and I can save the data no problem. I've even removed all my handling code to see if it was something I was doing.
I don't really want to ship with these errors showing, but I also have no idea what can be causing this error to appear. chatgpt was not helpful diagnosing this.
Does anyone know what can cause this error
Is there a way I can see the source code to figure out if there's something I'm doing wrong here?
It really seems like this is an internal apple error, or else I would have expected more details on the error relating to the code I've written. Any clues would be appreciated!
Topic:
Media Technologies
SubTopic:
Photos & Camera
Hello everyone,
I'm working on a feature where I need to capture the highest possible quality photo (e.g., 24MP on supported devices) and upload it to our server. I don't need the photos to appear in user's main Photos app so I thought I could store the photos in app's private directory using FileManager until they are uploaded. This wouldn't require requesting Photo Library permission, maximizing user privacy.
The documentation on AVCapturePhotoOutput states that "the 24MP setting (5712, 4284) is only serviced as 24MP when opted-in to autoDeferredPhotoDeliveryEnabled"
/**
@property maxPhotoDimensions
@abstract
Indicates the maximum resolution of the requested photo.
@discussion
Set this property to enable requesting of images up to as large as the specified dimensions. Images returned by AVCapturePhotoOutput may be smaller than these dimensions but will never be larger. Once set, images can be requested with any valid maximum photo dimensions by setting AVCapturePhotoSettings.maxPhotoDimensions on a per photo basis. The dimensions set must match one of the dimensions returned by AVCaptureDeviceFormat.supportedMaxPhotoDimensions for the current active format. Changing this property may trigger a lengthy reconfiguration of the capture render pipeline so it is recommended that this is set before calling -[AVCaptureSession startRunning].
Note: When supported, the 24MP setting (5712, 4284) is only serviced as 24MP when opted-in to autoDeferredPhotoDeliveryEnabled.
*/
@available(iOS 16.0, *)
open var maxPhotoDimensions: CMVideoDimensions
(btw. this note is not present in the docs https://developer.apple.com/documentation/avfoundation/avcapturephotooutput/maxphotodimensions)
Enabling autoDeferredPhotoDeliveryEnabled means that for a 24MP capture, the system will call the photoOutput(_:didFinishCapturingDeferredPhotoProxy:error:) delegate method, providing a proxy object instead of the final image data.
According to the WWDC23 session "Create a more responsive camera experience," this AVCaptureDeferredPhotoProxy must be saved to the PHPhotoLibrary using a PHAssetCreationRequest with the resource type .photoProxy. The system then handles the final processing in the background within the library.
To use deferred photo processing, you'll need to have write permission to the photo library to store the proxy photo, and read permission if your app needs to show the final photo or wants to modify it in any way.
https://developer.apple.com/videos/play/wwdc2023/10105/?time=799
This seems to create a hard dependency on the Photo Library for accessing 24MP images.
My question is:
Is there any way to receive the final, processed 24MP image data directly in the app after a deferred capture, without using PHPhotoLibrary as the processing intermediary?
For example, is there a delegate callback or a mechanism I'm missing that provides the final data for a deferred photo, allowing an app to handle it in-memory or in its own private sandbox, completely bypassing the user's Photo Library?
Our goal is to follow Apple's privacy-first principles by avoiding requesting a PHPhotoLibrary authorization when our app's core function doesn't require access to the user's photo collection.
Thank you for your time and any clarification you can provide.
Where can I find the documentation of the Genlock feature of the iPhone 17 Pro? How does it work and how can I use it in my app?
iPhone7 : iOS 14.0 Beta 5
Xcode-beta
Mac OS : 10.15.5 (19F101)
crash info :
** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[PHPhotoLibrary presentLimitedLibraryPickerFromViewController:]: unrecognized selector sent to instance xxxxxx'
terminating with uncaught exception of type NSException
my code:
(void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
if (@available(iOS 14, *)) {
[[PHPhotoLibrary sharedPhotoLibrary] presentLimitedLibraryPickerFromViewController:self];
}
}
So I've spent the last five years optimizing my video AI system so that it runs with less than 5% CPU while processing a 30fps video feed on a Macbook Pro M2, and everything is great, until Sonoma comes out, and I find myself consuming 40% CPU for the exact same workload.
So I fire up Instruments, and the "heaviest stack trace" (see screenshot) turns out to be Espresso doing some completely unasked-for and absolutely useless processing on my video frames. I turn off Reactions, but nothing helps - the CPU consumptions stays at 40%.
"Reactions" is nothing but a useless toy to please some WWDC keynote fanboys, I don't want it anywhere near my app or my users, and I especially do not want to take the blame for it pissing away the user's CPU cycles and battery.
Now, how do I make it go away, for ever?
Best regards
Jacob
I'm creating an app that uses AVCaptureSession to pass camera input to AVCaptureMetadataOutput type set [metaout setMetadataObjectTypes:@[AVMetadataObjectTypeFace]] and scan Face.
After updating to OS 26 Beta2 and iOS 26 Beta2, an issue has occurred where the delegate method of AVCaptureMetadataOutputObjectsDelegate is not called on some devices.
The following devices are experiencing this issue.
iPad (9th Gen)
iPad air (4th Gen)
iPhone 15
This issue has not occur on any other devices I have.
I tried running the AVFoundation sample code on the Apple Developer site on the above device. The same problem still occurs. [https://developer.apple.com/documentation/avfoundation/capture_setup/avcambarcode_detecting_barcodes_and_faces]
Are any additional settings required after OS 26 beta and iOS 26 beta? Or is there some problem on the OS side?
Issue:
In iOS 26 (tested on Developer Beta), AVCaptureMetadataOutputObjectsDelegate no longer receives callbacks when using .face detection.
metadataOutput.metadataObjectTypes = [.face]
I have an app that edits photos in your library. When I call
try CIContext().writeHEIFRepresentation(of: editedImage, to: fileURL, format: .RGBA8, colorSpace: originalImage.colorSpace!)
The following is logged to the console:
writeImageAtIndex:1012: ⭕️ ERROR: 'App' is trying to save an opaque image (5712x4284) with 'AlphaLast'. This would unnecessarily increase the file size and will double (!!!) the required memory when decoding the image --> ignoring alpha.
What does that mean and how can I resolve it?
Xcode Version 16.0 (16A242d)
iOS 18.1 (22B82)
Opening this question after discussing the issue in the AVCapture lab, hopefully so we can track down this issue.
We've been noticing some crashes in App Store Connect caused by layoutSublayers being called on a background thread.
After debugging the issue a bit we found that all calls which modified the AVCaptureSession or preview layer were indeed done on the main thread. It would be useful to see what results in AVCaptureVideoPreviewLayer.updateFormatDescription being called.
I've attached the crashlog below.
Crash log.ips - https://developer.apple.com/forums/content/attachment/800b0dba-3477-4c5a-b56c-f4cc393b384f