Explore the integration of web technologies within your app. Discuss building web-based apps, leveraging Safari functionalities, and integrating with web services.

All subtopics
Posts under Safari & Web topic

Post

Replies

Boosts

Views

Activity

Referer not being sent by WKWebView when using a custom scheme
YouTube now requires a Referer to be sent to be able to embed Youtube videos, otherwise the videos won't work. But WKWebView doesn't send a Referer when using a custom scheme, so Youtube videos stopped working in that case. This affects Ionic apps, both using Cordova or Capacitor. There's an open issue for Cordova and another one for Capacitor. In these apps, the app is served using a custom scheme like capacitor://localhost or ionic://localhost. I tried modifying the Ionic WebView source code to force adding a referrer to the URL loaded using WKWebView's loadRequest: [request addValue:@"https://my.test.app" forHTTPHeaderField:@"Referer"]; [_engineWebView loadRequest:request] But the Referer is still not sent in the Requests, I guess because the app is using a custom scheme (e.g. capacitor://localhost). However, if I modify this code to force loading an "online URL" (using https) instead of capacitor://localhost, then the my.test.app Referer is sent to the requests. Is there any way to make WKWebView send a Referer when using a custom scheme?
Topic: Safari & Web SubTopic: General Tags:
0
1
153
Nov ’25
Passkey PRF inconsistency between apple devices
Test Scenario: Initial Setup: Register a passkey on Chrome (MacBook) with cross-platform option The passkey syncs to iPhone via iCloud Both devices share same iCloud account Authentication Tests: Chrome on MacBook: Using hybrid transport (QR code with iPhone) → PRF output A Using platform authenticator → PRF output B (different) Safari on MacBook: Only uses platform authenticator → PRF output B Expected Behavior: When using same credential ID and salt, PRF output should be consistent across browsers/devices
3
1
567
Mar ’25
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.
5
0
961
Nov ’25
New IOS Safari CSS Issue with DVH & VH
After updating to the new iOS, in Safari, my overlays and backdrops using 100dvh no longer cover the full screen there's now a gap at the bottom. Switching to 100vh fixes it, but that causes scrolling issues on older Safari versions since 100vh includes extra height. Has anyone else experienced this? What's the recommended fix that works across iOS versions?
1
1
450
Oct ’25
Can’t Debug background.js in Safari App Extension (Manifest V3)
I’m developing a Safari App Extension and I want to debug the background.js script. However, I can’t find any tool or option to do this. When I run the extension from Xcode using the ProjectName Extension (macOS) scheme, I expect to see a “ProjectName” item under the Develop → Web Extension Background Content menu. But there’s nothing there. Has anyone encountered the same issue? How did you fix it? Environment: Manifest Version: V3 Safari: 26.0.1 (21622.1.22.11.15) Xcode: 26.0.1 (17A400)
1
1
682
Nov ’25
Issues Observed with App Clip Behavior and URL Handling
Hi Apple Team, We’ve noticed a couple of issues with launching default App Clip in safari and would appreciate your guidance. App Clip Popup Timing: When launching the App Clip using default URL, we sometimes see the small App Clip popup appear before the App Clip banner is displayed. Ideally, the banner should appear first. Cached URL Handling: In certain cases, the App Clip appears to be using a cached URL instead of the most recent one. For example, when we invoke two different App Clip URLs with unique parameters, the App Clip sometimes launches using the previous URL’s data instead of the new one. This behavior is inconsistent and makes it difficult to ensure users are directed to the correct experience each time. Could you please help us understand whether this is expected behavior or if there are any known issues or recommended solutions? Thank you for your time and support. Example
0
1
189
Oct ’25
CSS not displaying when using WKURLSchemeHandler on iOS 17+ with Xcode 15.3+
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
Topic: Safari & Web SubTopic: General
0
1
188
Feb ’25
Safari tabs lost updating to macOS 15.4
Problem As the title says, Safari lost all my tabs once I updated to macOS 15.4. I do of course have "Safari opens with: All windows from last session" set. This has been my default for many years. Past Mitigation In the past I had a script that I could use to backup ~/Library/Safari that would save all my bookmarks and tabs. Unfortunately they made this method of backup non-function sometime around when tab groups were introduced. Suggestion Fortunately my tab groups are still intact. But this sort of problem doesn't give me a lot of confidence. I haven't had something like this happen in a while, but when it does happen, it's quite frustrating. Apple really needs to recognize that this sort of thing can and will happen and they should make it easier for users to manually save/restore their tabs. Problem with forums To add insult to injury, as I was typing this message in the forum, I decided to select "Edit Bookmarks"... which proceeded to replace the current window with my bookmarks, thereby losing my post! It did this without warning of page content changes (which I get from most other websites). I felt somewhat relieved that the forum had recognized a previous draft and offered for me to continue. However, when I selected it, it brought me back to an old post... that was actually posted! smh
Topic: Safari & Web SubTopic: General Tags:
2
1
94
Apr ’25
No longe rable to obtain network name
We have a JavaScript api that queries our Secure Browser to get the network information – signal strength, network name, plugged in/wifi. Everything worked fine through the Tahoe betas, still does. Now we are getting on the network name and this is breaking our UI. Was this an intentional change or a bug? The other two properties still appear to be working. And it works in all lower MacOS versions. We are currently obtaining it through AppleScript try   set ssid to do shell script "system_profiler SPAirPortDataType | awk '/Current Network Information:/ {getline; sub(/^ +/, ""); sub(/:$/, ""); print}'"   if ssid is equal to "" then     return "Not connected to any Wi-Fi network."   else     return ssid   end if on error errMsg   return "Error: " & errMsg end try
Topic: Safari & Web SubTopic: General
2
0
374
Oct ’25
Chrome extension => Safari web extension packager
"The Safari web extension packager enables you to package and distribute your Safari extensions using App Store Connect from any web browser, without requiring a Mac or access to Xcode." I upload the unzipped folder I'd test in Chrome://extensions to the Safari web extension packager in App store connect. I get error: Embedded binary's bundle identifier is not prefixed with the parent app's bundle identifier. The only solution i've seen to this error involves xcode/a mac, being without which doesn't help
2
1
410
Oct ’25
Content blocker not removing content
I have a content blocker that generally works correctly, but I need to block an element that has certain text in it. For example, <span id="theId">Some text</span> is easy enough to block because I can locate the id and block that, but what if there is no id, or the id is completely random? What if it's just <span>Some text</span>? How do I block that? Let's say this is my only content blocker rule: [ { "action": { "type": "css-display-none", "selector": ":has-text(/Some text/i)" }, "trigger": { "url-filter": ".*" } } ] No errors are seen when the rule is loaded, so it's syntactically correct, it just doesn't block the HTML. I gather this is because :has-text() works on attributes, not contents, so it works on alt, href, aria-label etc. but not on the contents of the element itself. How do I block Some text in my example above? Thanks!
2
1
658
Feb ’25
Safe areas ignored after navigating a WebView/WebPage back in a NavigationStack
I'm using the new iOS 26 WebPage/WebView for SwiftUI in a NavigationStack. The initial load works as expected, but when loading items from the back/forward lists, the content jumps beneath the navigation bar: struct WebPageTestView: View { var webPage = WebPage() var body: some View { NavigationStack { WebView(webPage) .toolbar { Button("Back") { if let backItem = webPage.backForwardList.backList.last { webPage.load(backItem) } } Button("Forward") { if let forwardItem = webPage.backForwardList.forwardList.first { webPage.load(forwardItem) } } } } .task { webPage.isInspectable = true webPage.load(URL(string: "https://domchristie.co.uk/")) } } } I have run this on the iOS 26.0 and 26.1 Simulators and get the same issue. The demo website does not use any JavaScript. I was able to replicate this behaviour using a wrapped WKWebView and calling the .ignoresSafeArea(.all) modifier.
3
1
533
Oct ’25
Safari App crashes when running with Safari extension intermittently
I have observed Safari App starts crashing when running with my safari extension. Our Safari extension polls the host app every 60s. The extension receives and completes requests in func beginRequest(with context: NSExtensionContext) (we always call context.completeRequest(...)). The crash is intermittent: beginRequest itself does not throw. Looking for guidance about likely causes. I am attaching the snippet from crash report. Crashed Thread: 0 Dispatch queue: com.apple.main-thread Exception Type: EXC_CRASH (SIGKILL) Exception Codes: 0x0000000000000000, 0x0000000000000000 Termination Reason: Namespace RUNNINGBOARD, Code 3490524077 Thread 0 Crashed:: Dispatch queue: com.apple.main-thread 0 libsystem_kernel.dylib 0x1856f5c34 mach_msg2_trap + 8 1 libsystem_kernel.dylib 0x1857083a0 mach_msg2_internal + 76 2 libsystem_kernel.dylib 0x1856fe764 mach_msg_overwrite + 484 3 libsystem_kernel.dylib 0x1856f5fa8 mach_msg + 24 4 CoreFoundation 0x185822cbc __CFRunLoopServiceMachPort + 160 5 CoreFoundation 0x1858215d8 __CFRunLoopRun + 1208 6 CoreFoundation 0x185820a98 CFRunLoopRunSpecific + 572 7 HIToolbox 0x1912c327c RunCurrentEventLoopInMode + 324 8 HIToolbox 0x1912c64e8 ReceiveNextEventCommon + 676 9 HIToolbox 0x191451484 _BlockUntilNextEventMatchingListInModeWithFilter + 76 10 AppKit 0x189745a34 _DPSNextEvent + 684 11 AppKit 0x18a0e4940 -[NSApplication(NSEventRouting) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 688 12 Safari 0x1b801cce4 -[BrowserApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 228 13 AppKit 0x189738be4 -[NSApplication run] + 480 14 AppKit 0x18970f2dc NSApplicationMain + 880 15 Safari 0x1b83dd0b0 SafariMain + 468 16 dyld 0x185396b98 start + 6076
2
1
432
Sep ’25
Text rendering problem using OpenType font and cursive lookups with mixed RIGHT_TO_LEFT flag
Hi, I am developing an OpenType font with the following cursive feature. feature curs { lookup cursivejoinrtl; # RIGHT_TO_LEFT flag set between Hah, Meem, Yeh and final Meem lookup rehwawcursive; # RIGHT_TO_LEFT flag clear between Waw and Hah } curs; Here is the rendering of the word وحميم in TextEdit. Using HarfBuzz I got the following result. The same rendering problem occurs when using Safari. It seems that is related to Core Text. I reported the issue to Feedback Assistant over a year ago but haven't had a response yet. So I'm posting the problem on this forum. Any support on this matter would be greatly appreciated.
1
1
991
Nov ’25
Web view delayed layout during window resize
The app I work on uses WKWebView to render customer data. In iPadOS 26, we observe that there is a delay when resizing the window (and thus the web view) before the content is re-rendered. The same behavior is visible in Safari. For demonstration purposes, consider this test page: https://phet-dev.colorado.edu/html/build-an-atom/0.0.0-3/simple-text-only-test-page.html Initially, the window is small: Then when the window is expanded, the content scales up temporarily: It eventually re-renders to the correct size, but then if you make the window small again, you get (temporarily): Is there anyway around this behavior? We would love to have the content reflow interactively.
1
1
349
Sep ’25
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:
9
1
895
Sep ’25
JavaScriptCore crashed in iOS 17 and iOS 18
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.
4
1
702
Mar ’25
Missing Cookies in Set-Cookie Header in webRequest.onHeadersReceived callback in Safari Web Extension
We’re seeing an issue in our Safari Web Extension where not all cookies from the Set-Cookie response header are accessible. We are using macOS 15.4 and Safari 18.4. In the webRequest.onHeadersReceived callback, the Set-Cookie header returned by Safari only includes some of the cookies set by the server. If multiple Set-Cookie headers are present, we seem to receive only a partial list, some cookies are missing entirely. In Chrome and Firefox, the same callback provides all cookies set by the server without issue. We are looking for assistance in fixing these issues and having our Safari Extension function the same as it does in Firefox and Chrome.
0
1
193
Apr ’25