Hello, We’ve been using the CesiumJS WebGL library for several years, both on our website and within embedded WebViews in our iOS application. Since upgrading to iOS versions 18.2 and 18.3, we’ve started receiving numerous user complaints regarding application crashes on various iPad and iPhone models when loading CesiumJS. The crashes occur as soon as the 3D view initializes, and the error consistently reported is: "WebGL context lost" This issue appears to be a WebGL-related crash potentially triggered by GPU memory handling or allocation limits. However, we are not detecting any abnormal memory consumption prior to the crash, and the same setup works perfect on older iOS versions and on all Android devices and versions. Steps to Reproduce: Open: https://www.flightradar24.com/30.47,-94.84/8 Click on any aircraft icon on the map. In the aircraft details panel at the bottom, click on the “3D view” tab. On iOS 18.2 or 18.3, the page will crash shortly after initializing CesiumJS WebGL. Affected Devices: This issue is occurring across a wide range of devices, including: iPad 9th Generation iPad Pro (11-inch, 2nd Gen) iPhone SE (2020 and 2022) iPhone 11, 11 Pro iPhone XR iPhone Mini All of the above are running iOS 18.2 or 18.3. The problem does not occur on Android or previous iOS versions. Request: Has anyone else encountered similar issues with WebGL context loss after upgrading to iOS 18.2 or 18.3? Are there any known changes in memory limits or WebGL behavior in these recent iOS updates? We’d appreciate any insight or suggestions on workarounds or potential fixes. Thank you!

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>

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

Hi, I have an app that uses WKWebView and it's crashing on iOS 26 Simulator in places I've never had problems before. In this case it's crashing when calling WKWebView.callAsyncJavaScript, but in my other project WKWebView is crashing with some sort of EXC_BAD_ACCESS other than callAsyncJavaScript. Am I missing something? Thanks,

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

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.

Summary Recently a number of bugs affecting our Safari extension have been introduced with various Safari 18.X updates. We've submitted feedback for all of these, but most have received no response. We need to raise this to your attention as it has been affecting our developer experience and causing a lot of frustration for our users. It's something that adds a lot of uncertainty for us. These issues affect core web functionalities but seem to be isolated to the Start Page or Extension environments. For example: using window.open, no longer works using window.location.href = ... no longer works Including a tag in our start page causes infinite reloading to occur. registering a content script more than once will crash Safari Details Unable to open new window as as start page extension in Safari 18 FB15879470 What happens: Calling window.open does nothing. This broke our links to our feedback submission, marketing site & help site. When: Nov 18, 2024 - Initial launch of Safari 18 on macOS Status: Open, No response Unable to open app url scheme with window.location.href in start page extension in iOS 18 FB15879596 What happens: Changing the URL in this way does nothing (well actually it does work about 10% of the time). This broke our navigation to in app payment. When: Nov 18, 2024 - Initial launch of Safari 18 on iOS Status: Open, No response New tab extensions broken FB16126043 What happens: Having a tag in your causes an infinite loop of reloading the start page. This broke our entire start page extension. When: Dec 19, 2024 - Safari 18.3 on iOS beta Status: 10 similar tickets found, marked for future OS update. We did get a response and a fix is identified for a future release window.open opens “about:blank” when called from Start Page extension. FB16427985 What happens: calling window.open from the start page opens about blank on iOS 18.3. Similar to the first issue, but slightly different behaviour. This broke our links to our feedback submission, marketing site & help site. When: Jan 30, 2025 - Safari 18.3 Status: Open, No response Registering a content script more than once causes Safari to crash in macOS 15.4 beta FB16831768 What happens: We have an optional content script that we were registering every time it was used. Although somewhat redundant, it was much simpler than checking if one was already registered and tracking if an updated one needed to replace it. This works fine on all other browsers and all prior Safari versions we've released it on. However if a user enables site blocker on the latest version, as soon as they visit any website, our content script registration causes Safari to crash. Essentially preventing users from using Safari until they uninstall our extension. When: Mar 11, 2025 - Safari 18.4 Status: Open, No response In Conclusion Luckily we have been able to isolate and find workarounds for most of these issues so far, but we are not guaranteed to in the future. We are raising this not only to have these issues looked into, but to raise awareness of the rising trend of basic functionality of Safari extensions breaking with Safari updates. We hope that this can influence a shift in your QA & feedback intake practices to ensure these issues are less frequent in the future. We are happy to raise future issues through your provided channels as they are discovered. But to have our feedback ignored and then have to rely solely on workarounds to prevent disruptions to our users' experience is concerning. We submitted this feedback to our developer relations contact, and he suggested we submit a TSI to look into these issues. In response to this, we were advised to post this here.

I don't know why but all of a sudden when I build the extension it just doesn't load in Safari. The build executes fine but the extension doesn't load. Sometimes, through trying different combinations of clearing the build folder, building, archiving, ... it suddenly loads. And the next time I build again it doesn't load properly. So I can't do any work on it or test anything. I don't know why all of a sudden I am getting this behavior. It looks like engineers at Apple are constantly trying to overcomplicate a process that is at least ten times simpler in any other browser. This is ridiculous. Is this what our annual fee goes to? And they don't even provide any support for that. Several times I've tried to get some help here just to have to spend hours upon hours to figure it out by myself. I'm so tired of this.

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?

Starting in iOS 26 (tested on 26.1), when I use any of the “policy” methods of WKNavigationDelegate to return an action policy of cancel I get a trace like this printed to console: 1 0x18de71bbc WebKit::WebFramePolicyListenerProxy::ignore(WebKit::WasNavigationIntercepted) 2 0x18db3dd50 WebKit::NavigationState::NavigationClient::decidePolicyForNavigationAction(WebKit::WebPageProxy&, WTF::Ref<API::NavigationAction, WTF::RawPtrTraits<API::NavigationAction>, WTF::DefaultRefDerefTraits<API::NavigationAction>>&&, WTF::Ref<WebKit::WebFramePolicyListenerProxy, WTF::RawPtrTraits<WebKit::WebFramePolicyListenerProxy>, WTF::DefaultRefDerefTraits<WebKit::WebFramePolicyListenerProxy>>&&)::$_0::operator()(WKNavigationActionPolicy, WKWebpagePreferences*) 3 0x100189e5c $sSo24WKNavigationActionPolicyVIeyBhy_ABIeghy_TR 4 0x100189d38 $s16WebkitPolicyTrap14ViewControllerC03webD0_06decideB3For15decisionHandlerySo05WKWebD0C_So18WKNavigationActionCySo0lmB0VctF 5 0x100189df4 $s16WebkitPolicyTrap14ViewControllerC03webD0_06decideB3For15decisionHandlerySo05WKWebD0C_So18WKNavigationActionCySo0lmB0VctFTo 6 0x18db255c0 WebKit::NavigationState::NavigationClient::decidePolicyForNavigationAction(WebKit::WebPageProxy&, WTF::Ref<API::NavigationAction, WTF::RawPtrTraits<API::NavigationAction>, WTF::DefaultRefDerefTraits<API::NavigationAction>>&&, WTF::Ref<WebKit::WebFramePolicyListenerProxy, WTF::RawPtrTraits<WebKit::WebFramePolicyListenerProxy>, WTF::DefaultRefDerefTraits<WebKit::WebFramePolicyListenerProxy>>&&) 7 0x18dea9848 WebKit::WebPageProxy::decidePolicyForNavigationAction(WTF::Ref<WebKit::WebProcessProxy, WTF::RawPtrTraits<WebKit::WebProcessProxy>, WTF::DefaultRefDerefTraits<WebKit::WebProcessProxy>>&&, WebKit::WebFrameProxy&, WebKit::NavigationActionData&&, WTF::CompletionHandler<void (WebKit::PolicyDecision&&)>&&) 8 0x18dea7a34 WebKit::WebPageProxy::decidePolicyForNavigationActionAsync(IPC::Connection&, WebKit::NavigationActionData&&, WTF::CompletionHandler<void (WebKit::PolicyDecision&&)>&&) 9 0x18d9cbbf4 void IPC::handleMessageAsync<Messages::WebPageProxy::DecidePolicyForNavigationActionAsync, IPC::Connection, WebKit::WebPageProxy, WebKit::WebPageProxy, void (IPC::Connection&, WebKit::NavigationActionData&&, WTF::CompletionHandler<void (WebKit::PolicyDecision&&)>&&)>(IPC::Connection&, IPC::Decoder&, WebKit::WebPageProxy*, void (WebKit::WebPageProxy::*)(IPC::Connection&, WebKit::NavigationActionData&&, WTF::CompletionHandler<void (WebKit::PolicyDecision&&)>&&)) 10 0x18d9c7728 WebKit::WebPageProxy::didReceiveMessage(IPC::Connection&, IPC::Decoder&) 11 0x18e49a0d8 IPC::MessageReceiverMap::dispatchMessage(IPC::Connection&, IPC::Decoder&) 12 0x18df1908c WebKit::WebProcessProxy::dispatchMessage(IPC::Connection&, IPC::Decoder&) 13 0x18d9dfc28 WebKit::WebProcessProxy::didReceiveMessage(IPC::Connection&, IPC::Decoder&) 14 0x18e47f72c IPC::Connection::dispatchMessage(WTF::UniqueRef<IPC::Decoder>) 15 0x18e47fac4 IPC::Connection::dispatchIncomingMessages() 16 0x199ad3758 WTF::RunLoop::performWork() 17 0x199ad4eb0 WTF::RunLoop::performWork(void*) 18 0x1804563a4 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ 19 0x1804562ec __CFRunLoopDoSource0 20 0x180455a78 __CFRunLoopDoSources0 21 0x180454c4c __CFRunLoopRun 22 0x18044fcec _CFRunLoopRunSpecificWithOptions 23 0x1926be9bc GSEventRunModal 24 0x18630f0d8 -[UIApplication _run] 25 0x186313300 UIApplicationMain 26 0x18554ac38 block_destroy_helper.15 27 0x10018a70c $sSo21UIApplicationDelegateP5UIKitE4mainyyFZ 28 0x10018a67c $s16WebkitPolicyTrap11AppDelegateC5$mainyyFZ 29 0x10018a818 __debug_main_executable_dylib_entry_point 30 0x1000cd3d0 29 dyld 0x00000001000cd3d0 start_sim + 20 31 0x1002bab98 30 ??? 0x00000001002bab98 0x0 + 4297829272 This doesn’t happen in 18.6. Also, it doesn’t seem to have any negative consequences other than the console spam? But then, the navigation is being cancelled anyway, so maybe it’s trapping and just happens to have the effect of not loading the request? Anyway, I guess I can’t upload zips. But it’s pretty easy to reproduce. Just assign a WKWebView a navigationDelegate with an implementation like: func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping @MainActor (WKNavigationActionPolicy) -> Void) { decisionHandler(.cancel) } and then have it .load() anything. Have I been doing this wrong and 26 exposes it? Or is this a bug in 26? If the latter, any downstream consequences I should be looking out for? macOS 15.7.1 (24G231) Xcode 26.1.1 (17B100) iOS 26.1 (23B86)

Hi there I've been having trouble finding any details around how safari is supposed to behave when a FairPlay license expires. My assumption was that the video segments would stop getting decrypted and playback would stop, however I just see that the playback continues like nothing has happened. I've setup the "fps_safari_has_key_renewal.html" sample code from the Fairplay SDK and got encrypted playback working. The renewal method also appears to work. However, if I don't issue a renew call, or if I wait several minutes after the renew has succeeded the video never stops (my license is set with a 1 minute expiry so I can test this quickly). I've also observed that the MediaKeySession expiration property is always set to NaN even though my license has an expiry. I've tried with both Lease and Rental expiries set in the license (separately AND at the same time in separate tests). I'm using EZDRM as my drm provider. Just looking for some feedback on if this is supposed to work this way in safari or if license expiry isn't supported in safari. Thanks!

Hi, this is my first post in the community, so please correct me if i am posting this somewhat in a wrong manner. Im using my Apple M1 Pro(14inch, 2021) and installed the os 26 yesterday. Today, I was using Safari, and all of sudden it gets frozen, then the following window popped up. Is this something expected? i.e. my usage is somewhat unusual or is there any report around potential memory leak in Safari? appreciate any suggestions, as Safari is my main browser and currently on hold due to this issue. Thanks

I'm developing an application that needs smooth framerates within a wkwebview that interacts with native code. However, requestAnimationFrame by default is still throttled to 60hz even if all my target devices (the iPad Pro for example) have supported 120hz for a long time already. I noticed that the latest Safari in 18.3 beta supports unlocked framerates, but that's only under Safari feature flags. To my knowledge, these flags do not apply to WKWebView. Is there a way to enable unlocked framerate in WKWebView via requestAnimationFrame? (Calling JS at a faster rate from the native code side will not work, almost definitely, since WKWebView will still render at its own rate.) This is an experimental application for internal use and I'm okay if there are temporary beta solutions available.

Hi, now we could try WebGPU by manually enabling it in feature flags in no matter Safari or Safari technology preview on macOS. But, do we know when this WebGPU feature would be enabled by default or any plan to enable it by default in Safari? Thanks!

I'm encountering an issue with front camera video recordings via browser (Safari/Chrome) on devices running iOS/iPadOS 18 and above: On iPad, the recorded video appears upside down. On iPhone, the recorded video is rotated 90 degrees. The rear camera functions correctly without orientation issues. This problem seems specific to browser-based recordings, as the native Camera app records videos with the correct orientation. Has anyone else experienced this behavior? Is there a known workaround or fix? The preview while recording is fine, the recorded video is oriented incorrectly.

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 !

Hey there. I recently completed an Apple Pay (on the web) integration and it has been working fine, for the most part. I had one customer contact us saying that it didn't work on his devices though. I checked it out, and while it does normally work (and we've had over a thousand transactions use it) there does seem to be some scenarios where it fails and I'm not sure why. I was able to replicate his issue (or at least an issue) by using BrowserStack. When I click the button which should initiate the payment, everything works in the JS code until it gets to the applePaySession.begin() function call. Once it hits that, it just stops. No errors are generated and no notice is given that anything is wrong until you try to do it a second time. Then an error about a payment session already being active on the page is thrown. I'm not really sure how to troubleshoot this since I know it works on my old iPad Air 2, my current M4 Macbook, multiple other devices, and also works when scanning the QR code for use on an iPhone. There is some very specific thing with some very specific versions of Safari that seem to be tripping it up. If it helps, the version of Safari on the BrowserStack device is 18.1, but the version on my Macbook is 18.1.1. The version the customer who is having the issue is on is 18.2 according to him. The customer also says they have used ApplePay on other websites with no issues. I checked one of them and they appear to be using a PayPal integration, where as I am using the ApplePay SDK straight from Apple. There are quite a few variables at play here, and I'm just trying to narrow down what I should be looking at. If one person is reporting the issue, there are probably others with it as well.

Since iPadOS 18.x WKWebView seems to have a bug within its Fullscreen API (which can be enabled via WKPreferences.isElementFullscreenEnabled). This bug has the effect that websites trying to make an element (for example a video player) fullscreen fail to do so. This does not always happen, most of the time the fullscreen mode does work fine, but sometimes (far too often to be ignored) it does not. If an instance of WKWebView shows this issue, it can not be "fixed" by reloading the page or loading other pages, this issue exists in this instance forever. My App is a web browser App so I can create and remove WKWebView instance easily (by opening or closing Tabs). And there are times where I never see this bug, and times where ever other tab shows this bug. It's totally unreliable. The App does not show any issues at all when running under iPadOS 17 or older. The issue is only present under iPadOS 18.x. After some testing I've found out that when the bug has affected an instance of WKWebView, the JavaScript call element.requestFullscreen() will work if the element is a video element, but does no longer work if it is another element (like a DIV). If an instance of WKWebView is not affected by this bug, element.requestFullscreen() will work for all HTML elements. Does anyone has experienced this bug as well? And maybe found a workaround? Or maybe found a pattern which helps to find out what exactly is triggering this bug?

Hi, I'm developing an extension and I need to debug console logs that are logged in the Service Worker. The worker is configured in the manifest and is generally working as expected: However, when I open the browser, go to any site, and open Develop -> Service Workers or Develop -> Web Extension Background Content it is not visible there, so I can't really access the logs: But then I noticed that if I go out of focus from the browser for some time (and probably let the SW die), it becomes visible and I can open it without an issue: So, a couple of questions: Why isn't it instantly accessible? The extension Service Worker dev tools should be accessible regardless of what is happening to the tab or the browser, even if the SW terminates. Why does it eventually appear under Web Extension Background Content instead of the Service Workers when it is in fact an SW?

Hello We've encountered an issue with WKWebView in the latest iOS 26 beta. When loading a PDF URL, the background of the PDF viewer now displays as a dark gray instead of the expected white. Device: iOS 26 Simulator/Device Component: WKWebView Issue: The background color of the loaded PDF is gray. Expected Behavior: The background should be white, as it has been in all previous iOS versions. Link for Testing: https://help.apple.com/pdf/security/en_US/apple-platform-security-guide.pdf We confirmed that the same PDF and code render with a white background on iOS 26 and earlier. Questions: Is this an intentional change in iOS 26's WKWebView? If so, is there a new property or configuration setting available to control the background color of the PDF viewer within WKWebView? We would like to have the ability to set it back to white. Any insights, workarounds, or information on this matter would be greatly appreciated. Thank you.