Seeing an issue in some versions of Safari (16.6, 18.3, 18.5) where an APNG converted to AVIF does not support transparency. Instead of a transparent background, the background is filled with black.

It seems that in iOS 18.5+ built with Xcode 16.4+, there has been a breaking change since 18.4 with 16.3 within WebKit and how the navigationAction.sourceFrame property is initialized when implementing the decidePolicy delegate method. The flow goes: Implement a WKNavigationActionDelegate with decidePolicy Call WKWebView.loadHTMLString("some-string", baseURL: nil) Upon loading the HTML content, read the value of navigationAction.sourceFrame within the decidePolicy method of the WKNavigationActionDelegate On iOS 18.4 (and below) with Xcode 16.3 (and below); navigationAction.sourceFrame is <uninitialized> On iOS 18.5+ with Xcode 16.4+: navigationAction.sourceFrame is already initialized and is equal to navigationAction.targetFrame It appears that this change was made between minor versions of Xcode and is unexpected behavior of a minor version. Not only was this not called out in the release notes for Xcode 16.4 and iOS 18.5, but it's technically also a breaking change to the WebKit API. Can we get insight on why this change was made and what Apple's policy is on breaking changes between minor versions of Xcode/iOS?

Hello, my application experiences crashes related to JavaScriptCore in iOS 17 and 18. I would like to consult about potential causes, to determine whether it is a bug in JavaScriptCore or an issue with my code implementation. First, the crash stack always includes the call to JSC::MarkedBlock::aboutToMarkSlow(unsigned int). In the iOS 17 version, the crash occurs on this line, typically JSC::MarkedBlock::aboutToMarkSlow(unsigned int) + 88. In iOS 18 and later, the stack crashes atJSC::MarkedBlock::dumpInfoAndCrashForInvalidHandle(WTF::AbstractLocker&, JSC::HeapCell*). I checked the source code of JavaScriptCore for both iOS 17.6 and iOS 18.2 and observed modifications in the implementation of aboutToMarkSlow. My question is under what circumstances could this crash occur? crash.log I have attached a crash log encountered in iOS 18, hoping you can provide more effective information for problem diagnosis, especially since there are specific details worth noting near the crash registers. INVALID HANDLE: MarkedBlock = 0x141158000; heapCell = 0x14115bfa0; type = 0 INVALID HANDLE: found 24 0s at beginning of block INVALID HANDLE: block in another VM: 1, block in another VM: 1; other VM is 0x1324b6000 Moreover, in iOS 18.4, due to the implementation of dumpInfoAndCrashForInvalidHandleV2, the message has changed to: INVALID HANDLE 587: markedBlock=0x303518000; heapCell=0x303518fe0; cellFirst8Bytes=0; subspaceHash=0; contiguousZeros=0; totalzeros=0; blockVM=0x0; actualVM=0x0; isBlockVMValid=0; isBlockInSet=0; isBlockInDir=0; foundInBlockVM=0; INVALID HANDLE 606: markedBlock=0x303518000; heapCell=0x303518fe0; cellFirst8Bytes=0; subspaceHash=0; contiguousZeros=16384; totalZeros=16384; blockVM=0x0; actualVM=0x0; isBlockVMValid=0; isBlockInSet=0; isBlockInDir=0; foundInBlockVM=0; INVALID HANDLE 615: markedBlock=0x303518000; heapCell=0x303518fe0; cellFirst8Bytes=0; subspaceHash=0; contiguousZeros=16384; totalZeros=16384; blockVM=0x0; actualVM=0x0; isBlockVMValid=0; isBlockInSet=1; isBlockInDir=1; foundInBlockVM=0; (Further INVALID HANDLE messages follow the same format) I hope this provides you with more information.

Since iOS 18.1 launched as a beta, we've been getting reports from end users on iPhone 15 Pro and iPhone 15 Pro Max specifically. They're reporting that our WebView is unable to load our local HTML content. I'm curious if anyone else has had their app or users run into this issue? So far I've tried installing the most recent XCode Beta 16B5014f and installed an 18.1 emulator, but our app worked fine. It's also working fine on all my real devices, but we don't have a 15 Pro to test on. I'm curious if this is related to the processor on these devices and how they are intended to support Apple's new AI coming in 18.1.

Despite using the iPad in landscape mode, self-camera video is forced to portrait (Rotate 90 degrees). Only the video is portrait, even though the browser is in landscape orientation. Our app use getUserMedia() to get the video. The problem also happend in iPad Safari GoogleMeet. Details: The problem occurs even when the screen orientation is locked. After the video has been forced to portrait, rotating the iPad temporarily changes the video to landscape, but forces it to portrait again. It takes around 0 - 30 seconds before the video is forced to portrait. Both selfie camera and back camera I have confirmed this problem on the following devices iPad 8th iPadOS: 18.3.1 iPad10th iPadOS:18.3.1 iPadPro(M4) iPadOS:18.3.1 Some devices do not have this problem, even if they are the same model and OS version. I have tried the following restart factory reset Configuration changes (Settings > Apps > Safari) SETTINGS FOR WEBSITES Camera > Allow, Ask Microphone > Allow, Ask Advanced ＞ Feature Flags Reset All to Defaults Screen Orientation API (Locking / Unlocking) Screen Orientation API WebRTC AV1 codec Please help me to resolve this problom. Thanks.

When attempting to authorize an Apple Payment on an iOS 18 device using the scannable code in a non-Safari browser (i.e. Chrome), the payment sheet displays briefly, then dismisses. This same exact implementation of Apple Pay on the Web works flawlessly in Safari, so this feels like a bug given that the merchant session works fine in Safari. The following errors were found in my iOS device logs: (PassbookUIService) Codable: Failed to decode Merchant Session Created: Error Domain=NSCocoaErrorDomain Code=4864 UserInfo={NSDebugDescription=<private>, NSCodingPath=<private>} (PassbookUIService) Session 29592: Fatal Error: Failed to decode merchant session created`

Hi, in our app we have a WKWebView with complex web content that is loaded with cachePolicy: .reloadIgnoringLocalCacheData. If the app is in the background for several hours and returns in the foreground we noticed that the system reloads the webpage, but it does so with a cachePoliy returnCacheDataElseLoad. This could break the app if older cache content is present. To reproduce start an app in the simulator (tested with iOS 17.2), put it in the background and via activity monitor stop the processes com.apple.Webkit.WebContent com.apple.Webkit.networking After foreground the reload will happen. Two questions: why is this reload happening after some hours in the background? We haven't seen any crash reports related to this. It mostly happens on one of our test devices (iphone13 with iOS17.2.1). why is the webview reloading with a modified cachePolicy (returnCacheDataElseLoad)? Our temporary fix is to detect this case in "webView:decidePolicyFor navigationAction decisionHandler", cancel the request and reload with modified cachePolicy. Any ideas? Thanks, Heiko Sample code: class ViewController: UIViewController, WKNavigationDelegate, WKUIDelegate { var webView: WKWebView! override func viewDidLoad() { super.viewDidLoad() let config = WKWebViewConfiguration() webView = WKWebView(frame: .zero, configuration: config) webView.uiDelegate = self webView.navigationDelegate = self view.addSubview(webView) let myRequest = URLRequest(url: URL(string: "https://www.apple.com")!, cachePolicy: .reloadIgnoringLocalCacheData) print("request \(myRequest)") webView.load(myRequest) } func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) { print("start loading \(String(describing: navigationAction.request.url)), cache:\(navigationAction.request.cachePolicy)") decisionHandler(.allow) } override func viewDidLayoutSubviews() { super.viewDidLayoutSubviews() let fullscreen = CGRect.init(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height) webView.frame = fullscreen } }

I'm working on a Safari web extension that uses the nativeMessaging facility to communication with native code. When I want to notify the javascript extension from the embedding application, I use SFSafariApplication::dispatchMessage. As per the documentation, this call ... ensures that Safari is launched and that your extension is running before delivering the message. Everything works fine when the background script is running. However, after the background script gets unloaded at some point in time (non persistent background page, default behavior for a manifest V3 extension), the background script is not reloaded by the message from the native app (background script still appears unloaded in the developer menu of Safari, double-checked using a counter stored in browser.storage.local incremented on message reception). In this case, the completion handler of the application gets no error (error == nil) as if the message was correctly delivered. I was able to reproduce this behavior with the sample app delivered for WWDC20 (after upgrading the manifest from v2 to v3 to make it non-persistent). Is it supposed to work ? What I'm doing wrong ?

Dear Apple Developer Support, We are currently developing a system that requires the ability to edit Japanese vertical text within the Safari browser on iPhone. During our investigation, we encountered an issue that matches the following WebKit bug: 283620 – Caret Positioning Issues in Vertical Writing Mode We understand that this issue is being addressed in the following pull request: https://github.com/WebKit/WebKit/pull/39939 However, it appears that a complete fix has not yet been implemented. Given this situation, we would like to confirm the following: Is there any known workaround for this issue in iOS 17.5 or iOS 18.5 (the latest versions as of now)? If a workaround exists, could you please provide details? If not, could you share the expected timeline for a full resolution of this issue? Although this appears to be an open-source WebKit issue, we are reaching out to Apple because WebKit is tightly integrated with iOS and Safari, and ultimately delivered as part of the iPhone experience. Thank you very much for your support. Best regards, Takao Kurabayashi

Safari 18.0.1 on macOS 15.01 doesn't support the Passkey PRF extension during cross-device WebAuthn authentication when using QR code scanning, while it works correctly with iCloud passkeys. Steps to Reproduce: Clone and setup: git clone https://github.com/quocle108/passkey-prf-test yarn yarn start Test iCloud Passkey Flow: Open http://localhost:3000 in Safari Open DevTools (Cmd+Option+I) Click "Register" Choose "Passkey on iCloud" Expected console output: PRF supported: true Test Cross-Device Flow: Click "Register" Choose "Phone/Tablet" Scan QR with mobile device Expected: PRF supported: true PRF extension should be supported in cross-device flow, matching iCloud passkey behavior. Actual: PRF supported: false Cross-device flow returns empty extension results. Verify in Chrome Repeat steps 2-3 in Chrome Both flows return proper PRF extension results: PRF supported: true Test Environment: Browser: Safari 18.1.1 , Chrome 131.0.6778.70 OS: macOS 15.01 Mobile: iOS 18.x / Galaxy Note9 Android 10 Test repo: https://github.com/quocle108/passkey-prf-test

It seems fetch() does not include credentials (cookie) even when credentials: include is used and Safari extension has host_permissions for that domain when using from a non-default Safari profile. It includes credentials (cookie) when using from the default profile (which has the default name Personal). Is there anyone who has this problem? I try to request in popup.js like this: const response = await fetch( url, { method: 'GET', mode: 'cors', credentials: 'include', referrerPolicy: 'no-referrer', } ); and it does not include the credentials (cookie) from host_permissions. I already posted https://developer.apple.com/forums/thread/764279, and opened feedback assistant (FB15307169). But it is still not fixed yet. (macOS 15.4 beta 3) I hope this is fixed soon.

I recently upgraded my device from IOS 18.4 to IOS 26. My web extension has disapeared from safari. I can see it in Settings > Apps > Safari > Extensions and when I turn it on and re-open safari. I just get a mesasge that says "{extension name} is no longer avaiable". I have tried Manifest V2 and Manifest V3 both yield the same results. The current production extension bundled with the IOS app has the same problem. I can no longer use or test my own extension !? Help please !

I'm not loving the huge Favorites icons in Safari on MacOS 26, is there a way to reduce the size of them so that we can see more favorites on the list without scrolling down?

Hi guys, I'm trying to use sign in with apple in javascript, I followed the guider in the website, and almost find everything I can find in Google, but nothing help, here is my situation: I create a new App: com.yuhan.test.app I create a new service ID: com.yuhan.test.service configure a domain and return url domain: tts.perterpon.com returnURL: https://tts.perterpon.com/login create a new key for Sign In with Apple. my html code is here, it's easy, but it always told me invalid_client, I think I have done anything I need to do, can somebody help me? Thank you so much. you can test my online web site: https://tts.perterpon.com/login.html ` const buttonElementNew = document.getElementById('appleid-signin'); buttonElementNew.addEventListener('click', async () => { try { const data = await AppleID.auth.signIn() console.log('Try/Catch Data', data.authorization.id_token); const formData = new FormData(); formData.append("token", data.authorization.id_token); await fetch("", { method: "POST", body: formData, }); // Handle successful response. } catch (error) { // Handle error. } }); </script>

I’m encountering an issue with CSS not displaying when using WKURLSchemeHandler to load local HTML files. When I package the app using Xcode 15.3 or above, the CSS styles do not display on iOS 17 or higher. However, on iOS 16.7.1, the CSS displays correctly. • If I use Xcode 15.2 to package the app, the CSS loads and displays correctly on all iOS versions. I am using WKURLSchemeHandler to intercept and load the local HTML files. Is there any known issue or workaround for this? You can now post this in the “Safari & Web” section of the Apple Developer forums for further assistance! // // CustomURLSchemeHandler.m // HTMLTest // // Created by lvxue on 2024/9/23. // // CustomURLSchemeHandler.m #import "CustomURLSchemeHandler.h" @implementation CustomURLSchemeHandler - (void)webView:(WKWebView *)webView startURLSchemeTask:(id<WKURLSchemeTask>)urlSchemeTask { NSURL *url = urlSchemeTask.request.URL; //NSString *filePath; NSString *filePath = [[NSBundle mainBundle] pathForResource:@"index" ofType:@"html" inDirectory:@"LoaclHtml.bundle/A4"]; if ([url.lastPathComponent hasSuffix:@".css"]) { filePath = [[NSBundle mainBundle] pathForResource:@"style" ofType:@"css" inDirectory:@"LoaclHtml.bundle/A4/css"]; } else if ([url.lastPathComponent hasSuffix:@".js"]) { filePath = [[NSBundle mainBundle] pathForResource:@"yourJSFileName" ofType:@"js" inDirectory:@"LoaclHtml.bundle/A4/js"]; } NSData *htmlData = [NSData dataWithContentsOfFile:filePath]; NSString *mimeType = [self mimeTypeForPath:filePath]; NSURLResponse *response = [[NSURLResponse alloc] initWithURL:url MIMEType:mimeType expectedContentLength:htmlData.length textEncodingName:@"utf-8"]; [urlSchemeTask didReceiveResponse:response]; [urlSchemeTask didReceiveData:htmlData]; [urlSchemeTask didFinish]; } - (void)webView:(WKWebView *)webView stopURLSchemeTask:(id<WKURLSchemeTask>)urlSchemeTask { } - (NSString *)mimeTypeForPath:(NSString *)path { NSString *fileExtension = [path pathExtension]; if ([fileExtension isEqualToString:@"html"]) { return @"text/html"; } else if ([fileExtension isEqualToString:@"css"]) { return @"text/css"; } else if ([fileExtension isEqualToString:@"js"]) { return @"application/javascript"; } else if ([fileExtension isEqualToString:@"png"]) { return @"image/png"; } else if ([fileExtension isEqualToString:@"jpg"] || [fileExtension isEqualToString:@"jpeg"]) { return @"image/jpeg"; } else if ([fileExtension isEqualToString:@"gif"]) { return @"image/gif"; } return @"application/octet-stream"; } @end code-block

Our app, VitalSource Bookshelf, is an EPUB reader that uses a WKWebView to display book content. The EPUB content format is XHTML and uses namespaces (for the epub:type declaration). On beta 4, the webkit process repeatedly crashes when loading our content. The crash appears to be in the XML parser. Here's what's at the top of the stack trace: 0 WebCore 0x19166a878 WebCore::XMLDocumentParser::startElementNs(unsigned char const*, unsigned char const*, unsigned char const*, int, unsigned char const**, int, int, unsigned char const**) + 4968 1 libxml2.2.dylib 0x19c5a2bd0 xmlParseStartTag2 + 3940 2 libxml2.2.dylib 0x19c59e730 xmlParseTryOrFinish + 2984 3 libxml2.2.dylib 0x19c59d8e4 xmlParseChunk + 708 4 WebCore 0x191668ec8 WebCore::XMLDocumentParser::doWrite(WTF::String const&) + 636 5 WebCore 0x191665b78 WebCore::XMLDocumentParser::append(WTF::RefPtr<WTF::StringImpl, WTF::RawPtrTraits<WTF::StringImpl>, WTF::DefaultRefDerefTraits<WTF::StringImpl>>&&) + 304 6 WebCore 0x190105db0 WebCore::DecodedDataDocumentParser::appendBytes(WebCore::DocumentWriter&, std::__1::span<unsigned char const, 18446744073709551615ul>) + 268 7 WebCore 0x190861c3c WebCore::DocumentLoader::commitData(WebCore::SharedBuffer const&) + 1488 8 WebKit 0x18e07ca3c WebKit::WebLocalFrameLoaderClient::committedLoad(WebCore::DocumentLoader*, WebCore::SharedBuffer const&) + 52 9 WebCore 0x190869db4 WebCore::DocumentLoader::commitLoad(WebCore::SharedBuffer const&) + 228 10 WebCore 0x1909521e4 WebCore::CachedRawResource::notifyClientsDataWasReceived(WebCore::SharedBuffer const&) + 268 I was able to reproduce this in Safari on beta 4 just by opening the following trivial xhtml file from the file system - it does the same thing it does in our app, which is reloads and crashes several times, followed by the "A problem repeatedly occurred with..." error message. <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops" epub:prefix="vst: http://vitalsource.com/"><head></head><body class="dash" epub:type="chapter" data-begin-o="0" data-begin-o2="0" data-begin-o3="0" data-o="0" id="eid1844" data-end-o="14703" data-end-o2="14703" data-end-o3="14703"><h2 class="title" data-o="0" id="eid1845" data-out="33"><span class="label" data-o="0" id="eid1846"><span class="label-inner"><b data-o="0" id="eid1847">CHAPTER X</b> </span></span>THE SUBMARINE COAL-MINES</h2></body></html> I've also filed a feedback. But posting here just to raise the visibility - this is critical for us. I think it was introduced in beta 4; that's at least when we first noticed it. It was working in the earlier betas, I just don't remember if I tried beta 3 or not. It happens on iOS, macOS, and iPadOS. This has never been a problem in any earlier release of macOS / iOS.

When I open com. apple. developer. web browser, I am unable to inject JavaScript into the webview through methods such as addUserScript. The console will prompt 'ignoring user script injection for non app bound domain'

I'd like to know the install state of my iOS safari extension in the associated swift app. Is there any way to get this? As we have seen it is available for macOS here, is there anyway to know iOS Safari extension is enabled or not? Thanks

Based on the "Build immersive web experiences with WebXR"-Video for visionOS there is no way to disable the consent prompts for entering an immersive experience or consent hand-tracking. For the microphone it's possible to "greenlight" specific websites for mic input, which works great. I'd welcome it, if it were possible to add specific websites in the settings, in which those consent dialogs aren't shown each time. In my opinion, the user interaction through a button that launches the experience would be sufficient to not disorient.

Our current iOS application utilizes WKWebView to display a web application. We've observed intermittent deletion of non-expired 1st-party persistent cookies within this web application, leading to session drops. Here are our environment details and specific questions: Environment: App Build: Built with Xcode 16.2. WebView Class: WKWebView. Cookie Type: 1st-Party Persistent Cookie (Explicit expiration set, not a session cookie). Domain Configuration: The content server and the cookie-issuing server are the same (same IP address, same eTLD+1). The Cookie is set via the Set-Cookie HTTP Header on the server side. Questions: Automatic Deletion Policy: Are there any scenarios (e.g., related to iOS system behavior, Safari policies, or Intelligent Tracking Prevention (ITP)) where iOS or Safari might automatically delete non-expired 1st-party persistent cookies used by WKWebView? Deletion Conditions: If the answer to Q1 is Yes, under what specific conditions (e.g., memory pressure, inactivity, storage limits, specific ITP criteria) does this cookie deletion occur, and does the behavior differ significantly across various iOS versions? OS Update Impact: Are there any known specifications or documented cases where an iOS version update itself triggers the mass deletion of existing cookies stored in the WKWebsiteDataStore? Mitigation Strategy: If this automatic deletion is a known behavior, what mitigation strategies are officially recommended to ensure the persistence of essential 1st-party authentication cookies (e.g., manual synchronization with WKHTTPCookieStore or Keychain/UserDefaults)? Official Documentation: If the answer to Q1 is Yes, please provide URLs to any official Apple documentation or technical notes that detail the specifications or behavior of 1st-party persistent cookie deletion within WKWebView.