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File Download Support in SwiftUI Native WebView (iOS 26+)
I am using the native SwiftUI WebView and WebPage APIs (iOS 26+) and would like to implement file download functionality using the native SwiftUI WebView. However, I have not been able to find any APIs equivalent to WKDownload. In WKWebView, the WKDownload API can be used to handle downloads. I am looking for a similar API or recommended approach in the native SwiftUI WebView that would allow downloading files. If anyone has guidance or suggestions on how to implement this, I would appreciate your help.
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453
Feb ’26
WKWebView crashes in SSO App Extension on iOS 26 during loadRequest
We have a SAML-based SSO App Extension that uses WKWebView to load the SAML login request. This implementation has been working correctly on iOS versions prior to 26. However, starting with iOS 26, the extension consistently crashes when calling WKWebView.load(_:). The crash occurs inside WebKit, specifically in: /Library/Caches/com.apple.xbs/Sources/WebKit/Source/WebKit/UIProcess/WebsiteData/WebsiteDataStore.cpp at WebKit::WebPageProxy::loadRequest(...) No app-level exception is thrown, and the extension terminates with: Thread 10: EXC_BREAKPOINT (code=1, subcode=0x1a31dbe00) It appears that WKWebView initialization or WebsiteDataStore creation is now restricted in extension contexts on iOS 26, but this change is not documented in the SDK release notes. Could you please confirm if this is an intentional sandbox restriction in iOS 26 or a regression in WebKit? Steps to reproduce: Implement an App Extension using ASAuthorizationProviderExtensionAuthorizationRequest. Create a WKWebView instance in the extension. Attempt to load a SAML login request (POST request with headers). Observe immediate crash on iOS 26 (works fine on earlier versions). Expected behavior: WKWebView should load the request or fail gracefully as in prior releases, without crashing the extension process. Request: Please clarify if WKWebView usage inside extensions is officially unsupported as of iOS 26, and if so, recommend an alternative approach for handling SSO flows.
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1k
Nov ’25
Inquiry Regarding Vertical Writing Mode Caret Issues in Safari on iOS
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
Topic: Safari & Web SubTopic: General
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652
Jul ’25
iOS 26 crashes with CALayerInvalidGeometry when using magnifier on Webview
I have a Net8 Maui WebView app and whenever I use magnifier, it crashes. The magnifier works on iOS18 and lower but crashes on iOS26+ Exception **Type:** CALayerInvalidGeometry **Value:** CALayer position contains NaN: [nan 65]. Layer: <CALayer:0x123e88e40; position = CGPoint (0 0); bounds = CGRect (0 0; 0 48); delegate = <_UIEditMenuListView: 0x116f2f200; frame = (nan 0; 0 48); anchorPoint = (inf, 0); alpha = 0; layer = <CALayer: 0x123e88e40>>; sublayers = (<CALayer: 0x125232df0>, <CALayer: 0x123e88e70>); opaque = YES; allowsGroupOpacity = YES; anchorPoint = CGPoint (inf 0); opacity = 0> Stacktrace __exceptionPreprocess in unknown file [Line null, column null] (Not in app) objc_exception_throw in unknown file [Line null, column null] (Not in app) +[NSException raise:format:] in unknown file [Line null, column null] (Not in app) CA::Layer::set_position in unknown file [Line null, column null] (Not in app) -[CALayer setPosition:] in unknown file [Line null, column null] (Not in app) -[UIView _backing_setPosition:] in unknown file [Line null, column null] (Not in app) -[UIView setCenter:] in unknown file [Line null, column null] (Not in app) -[_UIEditMenuContentPresentation _displayPreparedMenu:titleView:reason:didDismissMenu:configuration:] in unknown file [Line null, column null] (Not in app) __54-[_UIEditMenuContentPresentation _displayMenu:reason:]_block_invoke in unknown file [Line null, column null] (Not in app) -[UIEditMenuInteraction _editMenuPresentation:preparedMenuForDisplay:completion:] in unknown file [Line null, column null] (Not in app) -[_UIEditMenuContentPresentation _displayMenu:reason:] in unknown file [Line null, column null] (Not in app) -[_UIEditMenuContentPresentation displayMenu:configuration:] in unknown file [Line null, column null] (Not in app) __58-[UIEditMenuInteraction presentEditMenuWithConfiguration:]_block_invoke in unknown file [Line null, column null] (Not in app) __80-[UIEditMenuInteraction _prepareMenuAtLocation:configuration:completionHandler:]_block_invoke in unknown file [Line null, column null] (Not in app) __109-[UITextContextMenuInteraction _editMenuInteraction:menuForConfiguration:suggestedActions:completionHandler:]_block_invoke in unknown file [Line null, column null] (Not in app) __107-[UITextContextMenuInteraction _querySelectionCommandsForConfiguration:suggestedActions:completionHandler:]_block_invoke in unknown file [Line null, column null] (Not in app)
Topic: Safari & Web SubTopic: General
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282
Aug ’25
@@extension_id replacement in CSS file fails in Sequoia, Safari 18
Typically, you can use the @@extension_id special string to reference the absolute path into the bundled resources of an extension, such as an image or a custom font, in a CSS file. However, this broke with Safari 18. Consider this section in a popup.css file: .card-icon { height: 16px; width: 20px; background-image: url(safari-web-extension://__MSG_@@extension_id__/images/card.svg); background-size: 20px 16px; } In Safari 17.4, once loaded in the browser, @@extension_id is replaced with E8BEA491-9B80-45DB-8B20-3E586473BD47, and the background-image reads as so: background-image: url(safari-web-extension://E8BEA491-9B80-45DB-8B20-3E586473BD47/images/card.svg); But as of Safari 18, the @@extension_id just collapses to an empty string, and the background-image reads as so: background-image: url(safari-web-extension:///images/card.svg); and the svg fails to load with the following error: "Failed to load resource: You do not have permission to access the requested resource." This is a regression, does to match the behavior of the other major browsers, and should be fixed. Filed with Feedback ID: FB15104807
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879
Apr ’25
WKWebView randomly does not send out cookies from WKWebSiteDataStore to our servers
PLATFORM AND VERSION iOS Development environment: Xcode 16.2, macOS 15.3.2 Run-time configuration: iOS 15-18 This happens in iOS, and leads to to the hybrid home page showing users as wrongly unauthenticated, since the at cookie is missing. For context, we have a JWT token that is stored in the Keychain, and on app launch, before any WKWebViews are created, we synchronize this to the WKWebsiteDataStore as an at cookie. We have analytics instrumentation on our websitef to show that WKWebView randomly refuses to send out any cookies. – The following is a snippet from an explanation to the WebKit Slack: We are having an issue on iOS, in which WKWebView loads pages (and even subsequent reloads) without any cookies, even though we have stored cookies in WKWebsiteDataStore.default() before hand right after application launch and becoming a key window. We reference this object, store it as a singleton, (as well as a process pool), and then all webview configurations are initialized with the same data store, the same process pool, every call on the main thread. From reading the source code, it seems that if the internal IPC logic fails, the APIs for deleting and setting data records and cookies fail without any feedback in completion handlers. This bug often happens when returning from the background on iOS after a few hours. Sometimes it happens on cold launches of the app. We have mitigated a similar issue (no cookies being sent) by implementing webViewWebContentProcessDidTerminate and reloading the webview ourselves, we found that whatever webview does to reload if that method is not implemented leads to cookies not being used. There have been multiple reports of WKWebView losing cookies in recent iOS versions, and we have tried to implement all of the workarounds listed. Setting a maximumAge to the cookies we store, and doing a _ = await websiteDataStore.dataRecords(ofTypes: Set([WKWebsiteDataTypeCookies])) before accessing or modifying websiteDataStore.httpCookieStore Question: is it safe to work with WKWebsiteDataStore before a WKWebView is added as a view, if so are there any timing considerations? Are there any logs that we can take a look at, this issue is very hard to reproduce, about 2% of our users face it at scale? Is there anything that could be happening within our process (runloop issues, timing) that could be causing this issue? See multiple reports from other companies that have faced the issue: "Now the Thermonuclear Problem with WKWebViewDataStorage" https://medium.com/axel-springer-tech/synchronization-of-native-and-webview-sessions-with-ios-9fe2199b44c9 STEPS TO REPRODUCE They don't exist, because the issue only happens at scale. We just know that no cookies are sent for a small percentage of requests. We believe this to be an issue in which Webkit fails to communicate internally with whatever IPC mechanisms it has. We have not been able to reproduce this issue consistently. The best we can give is that it happens after a few hours that the app is in the background. This happens regardless of whether the WKWebsiteDataStore is persistent or not, but seems to be much worse when it is persistent. Thus we have disabled persistnet data stores and relied on nonPersistent. The issue is bad enough that we are trying to move away from relying on cookies for iOS and just use request headers which we can only set on the top level request of WKWebView. DTS Case-ID: 13154329
Topic: Safari & Web SubTopic: General
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151
Apr ’25
WebView on macOS
Hello everyone, I am currently working on integrating a WebView into my macOS application, intended to allow users to browse tutorial webpages directly within the app. Although I’ve followed an example that appears syntactically correct, the WebView does not render any webpage content. Below is a code snippet for reference: import SwiftUI import WebKit struct HelpWebView: View { @State private var toggle = false @State private var page = WebPage() private var url: URL { toggle ? URL(string: "https://www.webkit.org")! : URL(string: "https://www.swift.org")! } var body: some View { WebView(page) .onAppear { page.load(URLRequest(url: url)) } .onChange(of: toggle) { page.load(URLRequest(url: url)) } .toolbar { Button("Reload", systemImage: "arrow.clockwise") { toggle.toggle() } } } } I would greatly appreciate any insights or suggestions on what might be causing this issue or how to resolve it. Thank you in advance for your help!
Topic: Safari & Web SubTopic: General Tags:
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375
Feb ’26
iOS React Native: Can two WebRTC stacks (Wazo & Jitsi) share media?
Hi everyone, I’m building a React Native iOS app where I’m integrating Wazo (native WebRTC) and Jitsi (WebView / WebRTC). Use case: Wazo is used to maintain a background call session (mainly signaling + audio keep-alive). Jitsi is used in the foreground for video calls. Problem: When Jitsi starts, it takes control of the microphone and camera. The Wazo call disconnects after ~5 minutes (likely due to media / audio session conflict). Even if Wazo audio/video is muted or tracks are disabled, the session still drops. My questions: Is it officially supported or recommended to run two WebRTC stacks (Wazo + Jitsi) simultaneously on iOS? Can Wazo stay connected without active audio/video tracks while Jitsi uses mic/camera? Is there a way to release Wazo media streams temporarily (but keep signaling alive) while Jitsi is loading or active? Are there any AVAudioSession / background mode limitations on iOS that make this impossible by design? If this is not supported, what is the recommended architecture (single WebRTC pipeline, switching media ownership, etc.)? Environment: iOS (React Native) Wazo SDK (native WebRTC) Jitsi Meet (WebView) CallKit + PushKit enabled Any guidance, documentation, or real-world experience would be greatly appreciated. Thanks in advance 🙏
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356
Jan ’26
On iOS 26 beta8, if a view's subview contains a WKWebView, using the CALayer's renderInContext method fails to capture the pixel
I’m experiencing an issue in WKWebView on iOS 26 Developer Beta 8. If a view's subview contains a WKWebView, using the CALayer's renderInContext method fails to capture the pixel at the current point, and the console outputs "unsupported surface format: &b38". The following code snippet was functioning as expected on iOS 18 and iOS 26 beta 1. However, it no longer works in the latest beta. Is this a known bug in the current iOS 26 betas, or is there a recommended workaround? - (BOOL)isTransparentAtTouchPoint:(CGPoint)point layer:(CALayer *)layer { unsigned char pixel[4] = {0}; CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef context = CGBitmapContextCreate(pixel, 1, 1, 8, 4, colorSpace, (CGBitmapInfo) kCGImageAlphaPremultipliedLast); CGContextTranslateCTM(context, -point.x, -point.y); [layer renderInContext:context]; CGContextRelease(context); CGColorSpaceRelease(colorSpace); CGFloat alpha = pixel[3] / 255.0f; return alpha < 0.01; }
Topic: Safari & Web SubTopic: General Tags:
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925
Sep ’25
iOS 18.4 HTTPS connection compatibility issue
We are experiencing a compatibility issue with our hybrid app related to the recent update in iPadOS 18.4, specifically concerning HTTPS connections. What are the key changes introduced in iPadOS 18.4 regarding HTTPS connections? Our app previously managed to bypass the DigitalSignature key usage missing error in the self-signed server certificate within the didReceiveAuthenticationChallenge method, as documented here: https://developer.apple.com/documentation/webkit/wknavigationdelegate/webview(_:didreceive:completionhandler:) . However, since the update to iPadOS 18.4, this method is no longer being called, resulting in direct failure of HTTPS connections. We are using cordova-ios 7.1. Thanks in advance for your help.
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215
Apr ’25
Safari Extension Stops on iOS 17.5.1 - 18
We are encountering an issue where the Safari extension we are developing stops working while in use on relatively new iOS versions (confirmed on 17.5.1, 17.6.1, and 18). Upon checking the Safari console, the content script is displayed in the extension script, so the background script or Service Worker must be stopping. The time until it stops is about 1 minute on 17.5.1 and about one day on 17.6.1 or 18. When it stops, we would like to find a way to restart the Service Worker from the extension side, but we have not found a method to do so yet. To restart the extension, the user needs to turn off the corresponding extension in the iPhone settings and then turn it back on. As mentioned in the following thread, it is written that the above bug was fixed in 17.6, but we recognize that it has not been fixed. https://forums.developer.apple.com/forums/thread/758346 On 17.5.1, adding the following process to the background script prevents it from stopping for about the same time as on 17.6 and above. // Will be passed into runtime.onConnect for processes that are listening for the connection event const INTERNAL_STAYALIVE_PORT = "port.connect"; // Try wake up every 9S const INTERVAL_WAKE_UP = 9000; // Alive port var alivePort = null; // Call the function at SW(service worker) start StayAlive(); async function StayAlive() { var wakeup = setInterval(() => { if (alivePort == null) { alivePort = browser.runtime.connect({ name: INTERNAL_STAYALIVE_PORT }); alivePort.onDisconnect.addListener((p) => { alivePort = null; }); } if (alivePort) { alivePort.postMessage({ content: "ping" }); } }, INTERVAL_WAKE_UP); } Additionally, we considered methods to revive the Service Worker when it stops, which are listed below. None of the methods listed below resolved the issue. ① Implemented a process to create a connection again if the return value of sendMessage is null. The determination of whether the Service Worker has stopped is made by sending a message from the content script to the background script and checking whether the message return value is null as follows. sendMessageToBackground.js let infoFromBackground = await browser.runtime.sendMessage(sendParam); if (!infoFromBackground) { // If infoFromBackground is null, Service Worker should have stopped. browser.runtime.connect({name: 'reconnect'}); // ← reconnection process // Sending message again infoFromBackground = await browser.runtime.sendMessage(sendParam); } return infoFromBackground.message; Background script browser.runtime.onConnect.addListener((port) => { if (port.name !== 'reconnect') return; port.onMessage.addListener(async (request, sender, sendResponse) => { sendResponse({ response: "response form background", message: "reconnect.", }); }); ② Verified whether the service worker could be restarted by regenerating Background.js and content.js. sendMessageToBackground.js export async function sendMessageToBackground(sendParam) { let infoFromBackground = await browser.runtime.sendMessage(sendParam); if (!infoFromBackground) { executeContentScript(); // ← executeScript infoFromBackground = await browser.runtime.sendMessage(sendParam); } return infoFromBackground.message; } async function executeContentScript() { browser.webNavigation.onDOMContentLoaded.addListener((details) => { browser.scripting.executeScript({ target: { tabId: details.tabId }, files: ["./content.js"] }); }); } However, browser.webNavigation.onDOMContentLoaded.addListener was not executed due to the following error. @webkit-masked-url://hidden/:2:58295 @webkit-masked-url://hidden/:2:58539 @webkit-masked-url://hidden/:2:58539 ③ Verify that ServiceWorker restarts by updating ContentScripts async function updateContentScripts() { try { const scripts = await browser.scripting.getRegisteredContentScripts(); const scriptIds = scripts.map(script => script.id); await browser.scripting.updateContentScripts(scriptIds);//update content } catch (e) { await errorLogger(e.stack); } } However, scripting.getRegisteredContentScripts was not executed due to the same error as in 2. @webkit-masked-url://hidden/:2:58359 @webkit-masked-url://hidden/:2:58456 @webkit-masked-url://hidden/:2:58456 @webkit-masked-url://hidden/:2:58549 @webkit-masked-url://hidden/:2:58549 These are the methods we have considered. If anyone knows a solution, please let us know.
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1.1k
Aug ’25
Tab title and URL properties are empty when accessed via WebExtensions API after Safari restart
Hello - we have a Mac application that uses a browser extension and the web extension JS APIs to communicate with Safari. During user testing we found that the tab title and tab URL properties are empty when obtaining the set of open windows via windows.get() after a Safari restart. We are testing with Safari 18.4 (20621.1.15.11.10). We have made a TestFlight version of our app and extension available to help with testing: https://testflight.apple.com/join/Va8Zdv9d. Screenshot and screen recording are attached to the Feedback ID supplied below. STEPS TO REPRODUCE Install Tabby via the TestFlight link Enable the Tabby for Safari extension in the Safari extensions dialog Grant permissions for Tabby for Safari to all windows all the time Within Safari, open two windows each with at least two tabs Within the Tabby app, ensure you see the windows and tabs listed correctly (tab title displayed for each) Quit and restart Safari Expected behavior Safari re-opens existing windows and Tabby displays title for each tab Observed Safari re-opens existing windows but within Tabby all tabs except the current tab are displayed with a title of “Start Page”. Under the hood the tab title and tab URL properties are empty when returned via a windows.get() call after Safari restarts. NAME AND APPLE ID OF APP Tabby - Browser Tab Manager 1586203406 FEEDBACK ASSISTANT ID FB16389506
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210
Aug ’25
Crash in WKScriptMessageHandler — CFRelease / CoreFoundation on iOS with WKWebView
We are building a hybrid iOS app using Angular (web) rendered inside a WKWebView, hosted by a native Swift app. Communication between the Angular UI and native Swift code is done using WKScriptMessageHandler. The app mostly works without issues, but in rare edge cases, we’re seeing crashes on the main thread, and the crash is reported in Firebase Crashlytics. The root cause appears related to CFRelease and WKScriptMessageHandler. Here’s the relevant crash stack: Crashed: com.apple.main-thread 0 CoreFoundation 0xbfac CFRelease + 44 1 CoreFoundation 0xa734 __CFURLDeallocate + 128 2 CoreFoundation 0x730c _CFRelease + 292 3 libobjc.A.dylib 0x4e28 AutoreleasePoolPage::releaseUntil(objc_object**) + 204 4 libobjc.A.dylib 0x4cbc objc_autoreleasePoolPop + 260 5 WebKit 0x99f194 WebKit::WebUserContentControllerProxy::didPostMessage(WTF::ObjectIdentifierGeneric<WebKit::WebPageProxyIdentifierType, WTF::ObjectIdentifierMainThreadAccessTraits<unsigned long long>, unsigned long long>, WebKit::FrameInfoData&&, WTF::ObjectIdentifierGeneric<WebKit::ScriptMessageHandlerIdentifierType, WTF::ObjectIdentifierMainThreadAccessTraits<unsigned long long>, unsigned long long>, std::__1::span<unsigned char const, 18446744073709551615ul>, WTF::CompletionHandler<void (std::__1::span<unsigned char const, 18446744073709551615ul>, WTF::String const&)>&&) + 680 6 WebKit 0x1b358 WebKit::WebUserContentControllerProxy::didReceiveMessage(IPC::Connection&, IPC::Decoder&) + 392 7 WebKit 0xe86b0 IPC::MessageReceiverMap::dispatchMessage(IPC::Connection&, IPC::Decoder&) + 272 8 WebKit 0x23c0c WebKit::WebProcessProxy::didReceiveMessage(IPC::Connection&, IPC::Decoder&) + 44 9 WebKit 0xe3f054 IPC::Connection::dispatchMessage(WTF::UniqueRef<IPC::Decoder>) + 252 10 WebKit 0x332d4 IPC::Connection::dispatchIncomingMessages() + 744 11 JavaScriptCore 0x58a7c WTF::RunLoop::performWork() + 204 12 JavaScriptCore 0x599a4 WTF::RunLoop::performWork(void*) + 36 13 CoreFoundation 0x56328 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 28 14 CoreFoundation 0x562bc __CFRunLoopDoSource0 + 176 15 CoreFoundation 0x53dc0 __CFRunLoopDoSources0 + 244 16 CoreFoundation 0x52fbc __CFRunLoopRun + 840 17 CoreFoundation 0x52830 CFRunLoopRunSpecific + 588 18 GraphicsServices 0x11c4 GSEventRunModal + 164 19 UIKitCore 0x3d2eb0 -[UIApplication _run] + 816 20 UIKitCore 0x4815b4 UIApplicationMain + 340 21 APP1 0xa2f80 main + 21 (AppDelegate.swift:21) 22 ??? 0x1c234eec8 (シンボルが不足しています) Steps: WebView: WKWebView Message passing: WKScriptMessageHandler → passing data from Angular → Swift WKWebView is long-lived and reused Native is using WKUserContentController.add(_:name:) to register handlers Crashes are intermittent (hard to reproduce), but often follow: Screen sleep/wake Push notification open Angular calling native immediately after resume Questions: Has anyone seen this specific crash pattern involving CFRelease and WKScriptMessageHandler? Are there known WebKit or CoreFoundation bugs related to WKScriptMessageHandler and retained URLs or message content? Thank you for your help!
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313
Jul ’25
WKWebview displays blank page intermittently on iOS and macOS
Our app connects to the headend to get a IDP login URL for each connection session, for example: “https://myvpn.ocwa.com/+CSCOE+/saml/sp/login?ctx=3627097090&amp;acsamlcap=v2” and then open embedded webview to load the page. (Note: the value of ctx is session token which changes every time). Quite often the webview shows blank white screen. After user cancel the connection and re-connect, the 2nd time webview loads the content successfully. The working case logs shows: didReceiveAuthenticationChallenge is called decidePolicyForNavigationAction is called twice didReceiveAuthenticationChallenge is called decidePolicyForNavigationResponse is called didReceiveAuthenticationChallenge is called But the failure case shows: Filed to terminate process: Error Domain=com.apple.extensionKit.errorDomain Code=18 "(null)" UserInfo={NSUnderlyingError=0x11461c240 {Error Domain=RBSRequestErrorDomain Code=3 "No such process found" UserInfo={NSLocalizedFailureReason=No such process found}}} didReceiveAuthenticationChallenge is called decidePolicyForNavigationAction is called decidePolicyForNavigationResponse is called If we stop calling evaluateJavaScript code to get userAgent, the blank page happens less frequently. Below is the code we put in makeUIView(): func makeUIView(context: Context) -&gt; WKWebView { if let url = URL(string: self.myUrl) { let request = URLRequest(url: url) webview.evaluateJavaScript("navigator.userAgent") { result, error in if let error = error { NSLog("evaluateJavaScript Error: \(error)") } else { let agent = result as! String + " " + self.myUserAgent webview.customUserAgent = agent webview.load(request) } } } return self.webview } Found some posts saying call evaluateJavaScript only after WKWebView has finished loading its content. However, it will block us to send the userAgent info via HTTP request. And I don’t think it is the root cause since the problem still occurs with less frequency. There is no problem to load same web page on Windows desktop and Android devices. The problem only occurs on iOS and macOS which both use WKWebview APIs. Is there a bug in WKWebview? Thanks, Ying
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292
Jul ’25
WebView Loading Issue iOS 18.1
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.
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3.8k
Jul ’25
macOS 26 beta 4 and iOS 26 beta 4 - WebKit XML parser crashes parsing XHTML with namespaces
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.
Topic: Safari & Web SubTopic: General
3
1
519
Aug ’25
Failing Network Requests in Safari due to DNS cache.
We are seeing network errors in Outlook mail on iOS and MacOS safari browsers. As per current investigation, we notice these network error when the user tries to use outlook after leaving it open on Safari for a while. Observations: Issue present in both MacOS and iOS safari. Issue is not present in other webkit browsers like brave and edge on iOS. Issue is reproable on both mini and big owa on safari browser. Issue is not related to post requests being sent in different packets on safari browser. Requests are only blocked for outlook.office/outlook.live domains What does not fix this issue? Reloading the application Clearing cookie, local storage or session storage Unregistering service workers Redirecting to a different page and coming back to outlook domain Re authenticating the users What fixes this issue? Reconnecting to wifi or mobile network Reconnecting vpn Removing safari from background and reopening Flushing the dns in setting
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2
196
Mar ’25
File Download Support in SwiftUI Native WebView (iOS 26+)
I am using the native SwiftUI WebView and WebPage APIs (iOS 26+) and would like to implement file download functionality using the native SwiftUI WebView. However, I have not been able to find any APIs equivalent to WKDownload. In WKWebView, the WKDownload API can be used to handle downloads. I am looking for a similar API or recommended approach in the native SwiftUI WebView that would allow downloading files. If anyone has guidance or suggestions on how to implement this, I would appreciate your help.
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0
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1
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453
Activity
Feb ’26
WKWebView crashes in SSO App Extension on iOS 26 during loadRequest
We have a SAML-based SSO App Extension that uses WKWebView to load the SAML login request. This implementation has been working correctly on iOS versions prior to 26. However, starting with iOS 26, the extension consistently crashes when calling WKWebView.load(_:). The crash occurs inside WebKit, specifically in: /Library/Caches/com.apple.xbs/Sources/WebKit/Source/WebKit/UIProcess/WebsiteData/WebsiteDataStore.cpp at WebKit::WebPageProxy::loadRequest(...) No app-level exception is thrown, and the extension terminates with: Thread 10: EXC_BREAKPOINT (code=1, subcode=0x1a31dbe00) It appears that WKWebView initialization or WebsiteDataStore creation is now restricted in extension contexts on iOS 26, but this change is not documented in the SDK release notes. Could you please confirm if this is an intentional sandbox restriction in iOS 26 or a regression in WebKit? Steps to reproduce: Implement an App Extension using ASAuthorizationProviderExtensionAuthorizationRequest. Create a WKWebView instance in the extension. Attempt to load a SAML login request (POST request with headers). Observe immediate crash on iOS 26 (works fine on earlier versions). Expected behavior: WKWebView should load the request or fail gracefully as in prior releases, without crashing the extension process. Request: Please clarify if WKWebView usage inside extensions is officially unsupported as of iOS 26, and if so, recommend an alternative approach for handling SSO flows.
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5
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0
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1k
Activity
Nov ’25
Inquiry Regarding Vertical Writing Mode Caret Issues in Safari on iOS
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
Topic: Safari & Web SubTopic: General
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0
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1
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652
Activity
Jul ’25
iOS 26 crashes with CALayerInvalidGeometry when using magnifier on Webview
I have a Net8 Maui WebView app and whenever I use magnifier, it crashes. The magnifier works on iOS18 and lower but crashes on iOS26+ Exception **Type:** CALayerInvalidGeometry **Value:** CALayer position contains NaN: [nan 65]. Layer: <CALayer:0x123e88e40; position = CGPoint (0 0); bounds = CGRect (0 0; 0 48); delegate = <_UIEditMenuListView: 0x116f2f200; frame = (nan 0; 0 48); anchorPoint = (inf, 0); alpha = 0; layer = <CALayer: 0x123e88e40>>; sublayers = (<CALayer: 0x125232df0>, <CALayer: 0x123e88e70>); opaque = YES; allowsGroupOpacity = YES; anchorPoint = CGPoint (inf 0); opacity = 0> Stacktrace __exceptionPreprocess in unknown file [Line null, column null] (Not in app) objc_exception_throw in unknown file [Line null, column null] (Not in app) +[NSException raise:format:] in unknown file [Line null, column null] (Not in app) CA::Layer::set_position in unknown file [Line null, column null] (Not in app) -[CALayer setPosition:] in unknown file [Line null, column null] (Not in app) -[UIView _backing_setPosition:] in unknown file [Line null, column null] (Not in app) -[UIView setCenter:] in unknown file [Line null, column null] (Not in app) -[_UIEditMenuContentPresentation _displayPreparedMenu:titleView:reason:didDismissMenu:configuration:] in unknown file [Line null, column null] (Not in app) __54-[_UIEditMenuContentPresentation _displayMenu:reason:]_block_invoke in unknown file [Line null, column null] (Not in app) -[UIEditMenuInteraction _editMenuPresentation:preparedMenuForDisplay:completion:] in unknown file [Line null, column null] (Not in app) -[_UIEditMenuContentPresentation _displayMenu:reason:] in unknown file [Line null, column null] (Not in app) -[_UIEditMenuContentPresentation displayMenu:configuration:] in unknown file [Line null, column null] (Not in app) __58-[UIEditMenuInteraction presentEditMenuWithConfiguration:]_block_invoke in unknown file [Line null, column null] (Not in app) __80-[UIEditMenuInteraction _prepareMenuAtLocation:configuration:completionHandler:]_block_invoke in unknown file [Line null, column null] (Not in app) __109-[UITextContextMenuInteraction _editMenuInteraction:menuForConfiguration:suggestedActions:completionHandler:]_block_invoke in unknown file [Line null, column null] (Not in app) __107-[UITextContextMenuInteraction _querySelectionCommandsForConfiguration:suggestedActions:completionHandler:]_block_invoke in unknown file [Line null, column null] (Not in app)
Topic: Safari & Web SubTopic: General
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1
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282
Activity
Aug ’25
@@extension_id replacement in CSS file fails in Sequoia, Safari 18
Typically, you can use the @@extension_id special string to reference the absolute path into the bundled resources of an extension, such as an image or a custom font, in a CSS file. However, this broke with Safari 18. Consider this section in a popup.css file: .card-icon { height: 16px; width: 20px; background-image: url(safari-web-extension://__MSG_@@extension_id__/images/card.svg); background-size: 20px 16px; } In Safari 17.4, once loaded in the browser, @@extension_id is replaced with E8BEA491-9B80-45DB-8B20-3E586473BD47, and the background-image reads as so: background-image: url(safari-web-extension://E8BEA491-9B80-45DB-8B20-3E586473BD47/images/card.svg); But as of Safari 18, the @@extension_id just collapses to an empty string, and the background-image reads as so: background-image: url(safari-web-extension:///images/card.svg); and the svg fails to load with the following error: "Failed to load resource: You do not have permission to access the requested resource." This is a regression, does to match the behavior of the other major browsers, and should be fixed. Filed with Feedback ID: FB15104807
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3
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1
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879
Activity
Apr ’25
WKWebView randomly does not send out cookies from WKWebSiteDataStore to our servers
PLATFORM AND VERSION iOS Development environment: Xcode 16.2, macOS 15.3.2 Run-time configuration: iOS 15-18 This happens in iOS, and leads to to the hybrid home page showing users as wrongly unauthenticated, since the at cookie is missing. For context, we have a JWT token that is stored in the Keychain, and on app launch, before any WKWebViews are created, we synchronize this to the WKWebsiteDataStore as an at cookie. We have analytics instrumentation on our websitef to show that WKWebView randomly refuses to send out any cookies. – The following is a snippet from an explanation to the WebKit Slack: We are having an issue on iOS, in which WKWebView loads pages (and even subsequent reloads) without any cookies, even though we have stored cookies in WKWebsiteDataStore.default() before hand right after application launch and becoming a key window. We reference this object, store it as a singleton, (as well as a process pool), and then all webview configurations are initialized with the same data store, the same process pool, every call on the main thread. From reading the source code, it seems that if the internal IPC logic fails, the APIs for deleting and setting data records and cookies fail without any feedback in completion handlers. This bug often happens when returning from the background on iOS after a few hours. Sometimes it happens on cold launches of the app. We have mitigated a similar issue (no cookies being sent) by implementing webViewWebContentProcessDidTerminate and reloading the webview ourselves, we found that whatever webview does to reload if that method is not implemented leads to cookies not being used. There have been multiple reports of WKWebView losing cookies in recent iOS versions, and we have tried to implement all of the workarounds listed. Setting a maximumAge to the cookies we store, and doing a _ = await websiteDataStore.dataRecords(ofTypes: Set([WKWebsiteDataTypeCookies])) before accessing or modifying websiteDataStore.httpCookieStore Question: is it safe to work with WKWebsiteDataStore before a WKWebView is added as a view, if so are there any timing considerations? Are there any logs that we can take a look at, this issue is very hard to reproduce, about 2% of our users face it at scale? Is there anything that could be happening within our process (runloop issues, timing) that could be causing this issue? See multiple reports from other companies that have faced the issue: "Now the Thermonuclear Problem with WKWebViewDataStorage" https://medium.com/axel-springer-tech/synchronization-of-native-and-webview-sessions-with-ios-9fe2199b44c9 STEPS TO REPRODUCE They don't exist, because the issue only happens at scale. We just know that no cookies are sent for a small percentage of requests. We believe this to be an issue in which Webkit fails to communicate internally with whatever IPC mechanisms it has. We have not been able to reproduce this issue consistently. The best we can give is that it happens after a few hours that the app is in the background. This happens regardless of whether the WKWebsiteDataStore is persistent or not, but seems to be much worse when it is persistent. Thus we have disabled persistnet data stores and relied on nonPersistent. The issue is bad enough that we are trying to move away from relying on cookies for iOS and just use request headers which we can only set on the top level request of WKWebView. DTS Case-ID: 13154329
Topic: Safari & Web SubTopic: General
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2
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1
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151
Activity
Apr ’25
WebView on macOS
Hello everyone, I am currently working on integrating a WebView into my macOS application, intended to allow users to browse tutorial webpages directly within the app. Although I’ve followed an example that appears syntactically correct, the WebView does not render any webpage content. Below is a code snippet for reference: import SwiftUI import WebKit struct HelpWebView: View { @State private var toggle = false @State private var page = WebPage() private var url: URL { toggle ? URL(string: "https://www.webkit.org")! : URL(string: "https://www.swift.org")! } var body: some View { WebView(page) .onAppear { page.load(URLRequest(url: url)) } .onChange(of: toggle) { page.load(URLRequest(url: url)) } .toolbar { Button("Reload", systemImage: "arrow.clockwise") { toggle.toggle() } } } } I would greatly appreciate any insights or suggestions on what might be causing this issue or how to resolve it. Thank you in advance for your help!
Topic: Safari & Web SubTopic: General Tags:
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1
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375
Activity
Feb ’26
iOS React Native: Can two WebRTC stacks (Wazo & Jitsi) share media?
Hi everyone, I’m building a React Native iOS app where I’m integrating Wazo (native WebRTC) and Jitsi (WebView / WebRTC). Use case: Wazo is used to maintain a background call session (mainly signaling + audio keep-alive). Jitsi is used in the foreground for video calls. Problem: When Jitsi starts, it takes control of the microphone and camera. The Wazo call disconnects after ~5 minutes (likely due to media / audio session conflict). Even if Wazo audio/video is muted or tracks are disabled, the session still drops. My questions: Is it officially supported or recommended to run two WebRTC stacks (Wazo + Jitsi) simultaneously on iOS? Can Wazo stay connected without active audio/video tracks while Jitsi uses mic/camera? Is there a way to release Wazo media streams temporarily (but keep signaling alive) while Jitsi is loading or active? Are there any AVAudioSession / background mode limitations on iOS that make this impossible by design? If this is not supported, what is the recommended architecture (single WebRTC pipeline, switching media ownership, etc.)? Environment: iOS (React Native) Wazo SDK (native WebRTC) Jitsi Meet (WebView) CallKit + PushKit enabled Any guidance, documentation, or real-world experience would be greatly appreciated. Thanks in advance 🙏
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356
Activity
Jan ’26
On iOS 26 beta8, if a view's subview contains a WKWebView, using the CALayer's renderInContext method fails to capture the pixel
I’m experiencing an issue in WKWebView on iOS 26 Developer Beta 8. If a view's subview contains a WKWebView, using the CALayer's renderInContext method fails to capture the pixel at the current point, and the console outputs "unsupported surface format: &b38". The following code snippet was functioning as expected on iOS 18 and iOS 26 beta 1. However, it no longer works in the latest beta. Is this a known bug in the current iOS 26 betas, or is there a recommended workaround? - (BOOL)isTransparentAtTouchPoint:(CGPoint)point layer:(CALayer *)layer { unsigned char pixel[4] = {0}; CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef context = CGBitmapContextCreate(pixel, 1, 1, 8, 4, colorSpace, (CGBitmapInfo) kCGImageAlphaPremultipliedLast); CGContextTranslateCTM(context, -point.x, -point.y); [layer renderInContext:context]; CGContextRelease(context); CGColorSpaceRelease(colorSpace); CGFloat alpha = pixel[3] / 255.0f; return alpha < 0.01; }
Topic: Safari & Web SubTopic: General Tags:
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9
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1
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925
Activity
Sep ’25
iOS 18.4 HTTPS connection compatibility issue
We are experiencing a compatibility issue with our hybrid app related to the recent update in iPadOS 18.4, specifically concerning HTTPS connections. What are the key changes introduced in iPadOS 18.4 regarding HTTPS connections? Our app previously managed to bypass the DigitalSignature key usage missing error in the self-signed server certificate within the didReceiveAuthenticationChallenge method, as documented here: https://developer.apple.com/documentation/webkit/wknavigationdelegate/webview(_:didreceive:completionhandler:) . However, since the update to iPadOS 18.4, this method is no longer being called, resulting in direct failure of HTTPS connections. We are using cordova-ios 7.1. Thanks in advance for your help.
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1
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1
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215
Activity
Apr ’25
How can I make an background image take up full screen space on ios26
How can I make a background image take the entire screen in ios26? I've tried position fixed, sticky, env() css variables but nothing worked. It does it when in PWA mode, but I would like to do so in the browser too.
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0
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1
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226
Activity
Aug ’25
Safari Extension Stops on iOS 17.5.1 - 18
We are encountering an issue where the Safari extension we are developing stops working while in use on relatively new iOS versions (confirmed on 17.5.1, 17.6.1, and 18). Upon checking the Safari console, the content script is displayed in the extension script, so the background script or Service Worker must be stopping. The time until it stops is about 1 minute on 17.5.1 and about one day on 17.6.1 or 18. When it stops, we would like to find a way to restart the Service Worker from the extension side, but we have not found a method to do so yet. To restart the extension, the user needs to turn off the corresponding extension in the iPhone settings and then turn it back on. As mentioned in the following thread, it is written that the above bug was fixed in 17.6, but we recognize that it has not been fixed. https://forums.developer.apple.com/forums/thread/758346 On 17.5.1, adding the following process to the background script prevents it from stopping for about the same time as on 17.6 and above. // Will be passed into runtime.onConnect for processes that are listening for the connection event const INTERNAL_STAYALIVE_PORT = "port.connect"; // Try wake up every 9S const INTERVAL_WAKE_UP = 9000; // Alive port var alivePort = null; // Call the function at SW(service worker) start StayAlive(); async function StayAlive() { var wakeup = setInterval(() => { if (alivePort == null) { alivePort = browser.runtime.connect({ name: INTERNAL_STAYALIVE_PORT }); alivePort.onDisconnect.addListener((p) => { alivePort = null; }); } if (alivePort) { alivePort.postMessage({ content: "ping" }); } }, INTERVAL_WAKE_UP); } Additionally, we considered methods to revive the Service Worker when it stops, which are listed below. None of the methods listed below resolved the issue. ① Implemented a process to create a connection again if the return value of sendMessage is null. The determination of whether the Service Worker has stopped is made by sending a message from the content script to the background script and checking whether the message return value is null as follows. sendMessageToBackground.js let infoFromBackground = await browser.runtime.sendMessage(sendParam); if (!infoFromBackground) { // If infoFromBackground is null, Service Worker should have stopped. browser.runtime.connect({name: 'reconnect'}); // ← reconnection process // Sending message again infoFromBackground = await browser.runtime.sendMessage(sendParam); } return infoFromBackground.message; Background script browser.runtime.onConnect.addListener((port) => { if (port.name !== 'reconnect') return; port.onMessage.addListener(async (request, sender, sendResponse) => { sendResponse({ response: "response form background", message: "reconnect.", }); }); ② Verified whether the service worker could be restarted by regenerating Background.js and content.js. sendMessageToBackground.js export async function sendMessageToBackground(sendParam) { let infoFromBackground = await browser.runtime.sendMessage(sendParam); if (!infoFromBackground) { executeContentScript(); // ← executeScript infoFromBackground = await browser.runtime.sendMessage(sendParam); } return infoFromBackground.message; } async function executeContentScript() { browser.webNavigation.onDOMContentLoaded.addListener((details) => { browser.scripting.executeScript({ target: { tabId: details.tabId }, files: ["./content.js"] }); }); } However, browser.webNavigation.onDOMContentLoaded.addListener was not executed due to the following error. @webkit-masked-url://hidden/:2:58295 @webkit-masked-url://hidden/:2:58539 @webkit-masked-url://hidden/:2:58539 ③ Verify that ServiceWorker restarts by updating ContentScripts async function updateContentScripts() { try { const scripts = await browser.scripting.getRegisteredContentScripts(); const scriptIds = scripts.map(script => script.id); await browser.scripting.updateContentScripts(scriptIds);//update content } catch (e) { await errorLogger(e.stack); } } However, scripting.getRegisteredContentScripts was not executed due to the same error as in 2. @webkit-masked-url://hidden/:2:58359 @webkit-masked-url://hidden/:2:58456 @webkit-masked-url://hidden/:2:58456 @webkit-masked-url://hidden/:2:58549 @webkit-masked-url://hidden/:2:58549 These are the methods we have considered. If anyone knows a solution, please let us know.
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1
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1
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1.1k
Activity
Aug ’25
Tab title and URL properties are empty when accessed via WebExtensions API after Safari restart
Hello - we have a Mac application that uses a browser extension and the web extension JS APIs to communicate with Safari. During user testing we found that the tab title and tab URL properties are empty when obtaining the set of open windows via windows.get() after a Safari restart. We are testing with Safari 18.4 (20621.1.15.11.10). We have made a TestFlight version of our app and extension available to help with testing: https://testflight.apple.com/join/Va8Zdv9d. Screenshot and screen recording are attached to the Feedback ID supplied below. STEPS TO REPRODUCE Install Tabby via the TestFlight link Enable the Tabby for Safari extension in the Safari extensions dialog Grant permissions for Tabby for Safari to all windows all the time Within Safari, open two windows each with at least two tabs Within the Tabby app, ensure you see the windows and tabs listed correctly (tab title displayed for each) Quit and restart Safari Expected behavior Safari re-opens existing windows and Tabby displays title for each tab Observed Safari re-opens existing windows but within Tabby all tabs except the current tab are displayed with a title of “Start Page”. Under the hood the tab title and tab URL properties are empty when returned via a windows.get() call after Safari restarts. NAME AND APPLE ID OF APP Tabby - Browser Tab Manager 1586203406 FEEDBACK ASSISTANT ID FB16389506
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5
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1
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210
Activity
Aug ’25
Crash in WKScriptMessageHandler — CFRelease / CoreFoundation on iOS with WKWebView
We are building a hybrid iOS app using Angular (web) rendered inside a WKWebView, hosted by a native Swift app. Communication between the Angular UI and native Swift code is done using WKScriptMessageHandler. The app mostly works without issues, but in rare edge cases, we’re seeing crashes on the main thread, and the crash is reported in Firebase Crashlytics. The root cause appears related to CFRelease and WKScriptMessageHandler. Here’s the relevant crash stack: Crashed: com.apple.main-thread 0 CoreFoundation 0xbfac CFRelease + 44 1 CoreFoundation 0xa734 __CFURLDeallocate + 128 2 CoreFoundation 0x730c _CFRelease + 292 3 libobjc.A.dylib 0x4e28 AutoreleasePoolPage::releaseUntil(objc_object**) + 204 4 libobjc.A.dylib 0x4cbc objc_autoreleasePoolPop + 260 5 WebKit 0x99f194 WebKit::WebUserContentControllerProxy::didPostMessage(WTF::ObjectIdentifierGeneric<WebKit::WebPageProxyIdentifierType, WTF::ObjectIdentifierMainThreadAccessTraits<unsigned long long>, unsigned long long>, WebKit::FrameInfoData&&, WTF::ObjectIdentifierGeneric<WebKit::ScriptMessageHandlerIdentifierType, WTF::ObjectIdentifierMainThreadAccessTraits<unsigned long long>, unsigned long long>, std::__1::span<unsigned char const, 18446744073709551615ul>, WTF::CompletionHandler<void (std::__1::span<unsigned char const, 18446744073709551615ul>, WTF::String const&)>&&) + 680 6 WebKit 0x1b358 WebKit::WebUserContentControllerProxy::didReceiveMessage(IPC::Connection&, IPC::Decoder&) + 392 7 WebKit 0xe86b0 IPC::MessageReceiverMap::dispatchMessage(IPC::Connection&, IPC::Decoder&) + 272 8 WebKit 0x23c0c WebKit::WebProcessProxy::didReceiveMessage(IPC::Connection&, IPC::Decoder&) + 44 9 WebKit 0xe3f054 IPC::Connection::dispatchMessage(WTF::UniqueRef<IPC::Decoder>) + 252 10 WebKit 0x332d4 IPC::Connection::dispatchIncomingMessages() + 744 11 JavaScriptCore 0x58a7c WTF::RunLoop::performWork() + 204 12 JavaScriptCore 0x599a4 WTF::RunLoop::performWork(void*) + 36 13 CoreFoundation 0x56328 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 28 14 CoreFoundation 0x562bc __CFRunLoopDoSource0 + 176 15 CoreFoundation 0x53dc0 __CFRunLoopDoSources0 + 244 16 CoreFoundation 0x52fbc __CFRunLoopRun + 840 17 CoreFoundation 0x52830 CFRunLoopRunSpecific + 588 18 GraphicsServices 0x11c4 GSEventRunModal + 164 19 UIKitCore 0x3d2eb0 -[UIApplication _run] + 816 20 UIKitCore 0x4815b4 UIApplicationMain + 340 21 APP1 0xa2f80 main + 21 (AppDelegate.swift:21) 22 ??? 0x1c234eec8 (シンボルが不足しています) Steps: WebView: WKWebView Message passing: WKScriptMessageHandler → passing data from Angular → Swift WKWebView is long-lived and reused Native is using WKUserContentController.add(_:name:) to register handlers Crashes are intermittent (hard to reproduce), but often follow: Screen sleep/wake Push notification open Angular calling native immediately after resume Questions: Has anyone seen this specific crash pattern involving CFRelease and WKScriptMessageHandler? Are there known WebKit or CoreFoundation bugs related to WKScriptMessageHandler and retained URLs or message content? Thank you for your help!
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1
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313
Activity
Jul ’25
WKWebview displays blank page intermittently on iOS and macOS
Our app connects to the headend to get a IDP login URL for each connection session, for example: “https://myvpn.ocwa.com/+CSCOE+/saml/sp/login?ctx=3627097090&amp;acsamlcap=v2” and then open embedded webview to load the page. (Note: the value of ctx is session token which changes every time). Quite often the webview shows blank white screen. After user cancel the connection and re-connect, the 2nd time webview loads the content successfully. The working case logs shows: didReceiveAuthenticationChallenge is called decidePolicyForNavigationAction is called twice didReceiveAuthenticationChallenge is called decidePolicyForNavigationResponse is called didReceiveAuthenticationChallenge is called But the failure case shows: Filed to terminate process: Error Domain=com.apple.extensionKit.errorDomain Code=18 "(null)" UserInfo={NSUnderlyingError=0x11461c240 {Error Domain=RBSRequestErrorDomain Code=3 "No such process found" UserInfo={NSLocalizedFailureReason=No such process found}}} didReceiveAuthenticationChallenge is called decidePolicyForNavigationAction is called decidePolicyForNavigationResponse is called If we stop calling evaluateJavaScript code to get userAgent, the blank page happens less frequently. Below is the code we put in makeUIView(): func makeUIView(context: Context) -&gt; WKWebView { if let url = URL(string: self.myUrl) { let request = URLRequest(url: url) webview.evaluateJavaScript("navigator.userAgent") { result, error in if let error = error { NSLog("evaluateJavaScript Error: \(error)") } else { let agent = result as! String + " " + self.myUserAgent webview.customUserAgent = agent webview.load(request) } } } return self.webview } Found some posts saying call evaluateJavaScript only after WKWebView has finished loading its content. However, it will block us to send the userAgent info via HTTP request. And I don’t think it is the root cause since the problem still occurs with less frequency. There is no problem to load same web page on Windows desktop and Android devices. The problem only occurs on iOS and macOS which both use WKWebview APIs. Is there a bug in WKWebview? Thanks, Ying
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0
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1
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292
Activity
Jul ’25
WebView Loading Issue iOS 18.1
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.
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4
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1
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3.8k
Activity
Jul ’25
macOS 26 beta 4 and iOS 26 beta 4 - WebKit XML parser crashes parsing XHTML with namespaces
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.
Topic: Safari & Web SubTopic: General
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3
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1
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519
Activity
Aug ’25
iOS Safari Extension State
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
Replies
2
Boosts
1
Views
675
Activity
Jul ’25
Failing Network Requests in Safari due to DNS cache.
We are seeing network errors in Outlook mail on iOS and MacOS safari browsers. As per current investigation, we notice these network error when the user tries to use outlook after leaving it open on Safari for a while. Observations: Issue present in both MacOS and iOS safari. Issue is not present in other webkit browsers like brave and edge on iOS. Issue is reproable on both mini and big owa on safari browser. Issue is not related to post requests being sent in different packets on safari browser. Requests are only blocked for outlook.office/outlook.live domains What does not fix this issue? Reloading the application Clearing cookie, local storage or session storage Unregistering service workers Redirecting to a different page and coming back to outlook domain Re authenticating the users What fixes this issue? Reconnecting to wifi or mobile network Reconnecting vpn Removing safari from background and reopening Flushing the dns in setting
Replies
0
Boosts
2
Views
196
Activity
Mar ’25
ios 18.2 We are facing issue in WKwebview load the Epub file
Hi, We are facing a major issue with our application. We are using FolioReaderkit to read epub files. Currently, it's working on the iOS 18.1 device and simulator, but it's not working on the iOS 18.2 and later version devices. we are facing this error in Folioreaderkit
Replies
4
Boosts
1
Views
253
Activity
Mar ’25