After updating Xcode to the latest version we observed that SFSafariViewController is not loading web pages on Xcode 16 Simulator with iOS 18, whenever it is presented the View Controller is empty (does not load any content) and the app freezes, but other screens that use WKWebView are working normally. Also, during tests on physical devices with iOS 18 it seems to work just fine, so it might be just a IDE version problem. Is anyone experiencing the same issue? If so, did anyone find a solution for it?

I'm experiencing a Safari Web Extension issue where the non-persistant background script seems to crash after 30 seconds even when the content script is messaging it. Here is a minimal-reproducible example. When running in an emulator, the background script will stay responsive forever. However, when running on a physical device, the background script becomes non-responsive after 30 seconds of activity. It never becomes responsive again until I toggle the extensions enable/disable toggle, after which it stays active for 30 seconds and then crashes again.

Safari cannot open the page due to the error 'WebKit encountered an internal error.' We are using https://github.com/stleamist/BetterSafariView.git, and it was working fine before we updated to Xcode 16.

Hi everyone, I’m encountering a serious reliability issue with message passing in my Safari extension on iOS 18.4.1 and iOS 18.5 In my extension, I use the standard messaging API where the background script sends a message to the content scrip. The content script is listening using: browser.runtime.onMessage.addListener(handler); This setup has been working reliably in previous versions of iOS, but since updating to iOS 18.4.1 and iOS 18.5, I’ve noticed that messages sent from the background script are not consistently received by the content script. From my logs, I can confirm that: The background script is sending the message. The content script’s listener is not always triggered. There are no errors or exceptions logged in either script. It seems as if browser.runtime.onMessage.addListener is either not getting registered in time or failing silently in some instances. This issue is intermittent and does not occur all the time. Has anyone else experienced similar issues in iOS 18.4.1 and 18.5? Are there any known changes or workarounds for ensuring reliable communication between background and content scripts in this version? Any help or insights would be greatly appreciated. Thanks!

I’m experiencing a crash in WKWebView on iOS 26 Developer Beta 5 and Beta 6 with the following exception: CALayer position contains NaN: [nan 65] The crash occurs when the following CSS properties are applied to content displayed in WKWebView: -webkit-user-select: none; -webkit-touch-callout: none; This issue happens consistently whenever these styles are set, leading to the crash inside WKWebView. Is this a known bug in the current iOS 26 betas, or is there a recommended workaround?

I'm converting a Chrome Extension to a Safari Web Extension, I found it's not easy to get favicon of current tab/url natively. The tab object in Safari doesn't have favIconUrl. { 	"id": 121, 	"index": 6, 	"active": true, 	"width": 1324, 	"audible": false, 	"url": "https://github.com/", 	"mutedInfo": { 		"muted": false 	}, 	"windowId": 2, 	"title": "GitHub", 	"incognito": false, 	"pinned": false, 	"height": 935, 	"highlighted": true, 	"status": "complete" } 		 2. I didn't find Safari has similar thing like chrome://favicon 3. I found Safari's favicon caches in ~/Library/Safari/Favicon Cache/favicons but have no idea how to use them in Safari Web Extension.

Hi there! I'm new to App Development and I'm running into the following error when playing audio on a website loaded through a WKWebView: 0x112000cc0 - ProcessAssertion::acquireSync Failed to acquire RBS assertion 'WebKit Media Playback' for process with PID=70.197, error: Error Domain=RBSServiceErrorDomain Code=1 "(originator doesn't have entitlement com.apple.runningboard.assertions.webkit AND originator doesn't have entitlement com.apple.multitasking.systemappassertions)" UserInfo={NSLocalizedFailureReason=(originator doesn't have entitlement com.apple.runningboard.assertions.webkit AND originator doesn't have entitlement com.apple.multitasking.systemappassertions)} Looking through this forum, it seems more people have this issue, yet no one has found a solution (or posted it...). The solutions that I did find (Background Modes capability, webView.configuration.allowsInlineMediaPlayback = true), did nothing. To make sure the issue had nothing to do with my own code, I created an empty project to reproduce the issue. I'm not sure on the best way to share it, but it's a small file (forgive me, I have no clue what it does, actually chatGPT made it for me. My real application is a WebApp wrapped with Capacitor, so it handles all the Swift stuff) import SwiftUI import WebKit struct WebView: UIViewRepresentable { let urlString: String func makeUIView(context: Context) -> WKWebView { let webView = WKWebView() webView.configuration.allowsInlineMediaPlayback = true webView.configuration.allowsAirPlayForMediaPlayback = true webView.navigationDelegate = context.coordinator return webView } func updateUIView(_ uiView: WKWebView, context: Context) { if let url = URL(string: urlString) { let request = URLRequest(url: url) uiView.load(request) } } func makeCoordinator() -> Coordinator { Coordinator(self) } class Coordinator: NSObject, WKNavigationDelegate { var parent: WebView init(_ parent: WebView) { self.parent = parent } func webView(_ webView: WKWebView, didFailProvisionalNavigation navigation: WKNavigation!, withError error: Error) { print("Web page loading failed: \(error.localizedDescription)") } } } struct WebViewDemo: View { var body: some View { NavigationView { WebView(urlString: "https://www.w3schools.com/html/tryit.asp?filename=tryhtml5_audio_all") .navigationBarTitle("Web View") } } } struct WebView_Previews: PreviewProvider { static var previews: some View { WebViewDemo() } } Nothing special, right? When I build the app and navigate to a website that has an tag (https://www.w3schools.com/html/tryit.asp?filename=tryhtml5_audio_all). I still see the error when I play the audio. It plays nonetheless, but the error is there. I'm not at all interested in actually playing audio in the background/when the app is closed/suspended. I just want the error to go away! I've tried different iOS versions (14,15,16,17), but the problem persists. Anyone know what's happening?

In Safari Web Extensions on iOS 18, declarativeNetRequest Rulesets and Dynamic Rules take over twice as long to apply -- which causes rulesets to often fail to apply before sites load. In a boilerplate Xcode project you can note the time difference toggling the OISD (https://oisd.nl) ruleset on iOS 17 and iOS 18 simulators. Additionally, if you force quit Safari and reopen to a site with ads blocked by OISD list (e.g. espn.com) the content will be blocked in that initial state on iOS 17, but not in iOS 18 due to the latency. Based on the boilerplate extension, this bug is impacting all Mobile Safari Extensions using declarativeNetRequest Rulesets and Dynamic Rules. We know several other extension developers dealing with this issue. Our team wrote detailed reproduction steps in our Feedback Assistant ticket: https://feedbackassistant.apple.com/feedback/15196130 but have received no responses. I would attach a screen recording here but it won't allow me.

Hi Folks, do you know what happend with the "shape detection API" feature flag on Safari 18.X (IOs 18.X)?... in previous versions (17.X) i enabled the "shape detection API" feature flag and was able to detect codes like mentioned here... https://developer.mozilla.org/en-US/docs/Web/API/Barcode_Detection_API#browser_compatibility I built a PWA (Service Worker) with Angular 18 and facing this issue immediately after updating to IOS 18.0 (I enabled/disabled the flag, restartet the device several times... no success at all) Do you have an Idea what changed or how i can enable that feature again? Thx a lot in advance.. Cheers Martin

Hi everyone, I’m encountering a critical reliability issue with message passing in my Safari Web Extension on iOS 18.4.1 and iOS 18.5. In my extension, I’m using the standard messaging API. The background script sends a message to the content script using browser.tabs.sendMessage(...), and the content script registers a listener via: browser.runtime.onMessage.addListener(handler); This setup has been working reliably in all prior versions of iOS. However, after updating to iOS 18.4.1 and 18.5, I’ve noticed the following behavior: ✅ The content script is successfully injected, and onMessage.addListener is registered (I see logging confirming this). ✅ The background script sends the message using the correct tabId (also confirmed via logs). ❌ The content script’s onMessage listener is not consistently triggered. ⚠️ This issue is intermittent, sometimes the message is received, sometimes it is silently dropped. ❌ No exceptions or errors are thrown in either script, the message appears to be sent, but not picked up from the content script message listener.

Summary: Content scripts injected via manifest continue to receive and respond to chrome.tabs.sendMessage() calls even after the user has navigated away from the original page, causing messages intended for the current tab to be handled by zombie contexts from previous pages. Environment: Safari/iOS Version: 18.5 Extension Manifest: Version 3 Expected Behavior: When a user navigates from Page A to Page B: Page A's content script context should be destroyed. chrome.tabs.sendMessage(currentTabId, message) should only reach Page B's content script Only Page B should be able to respond to action button clicks (or other background to content messages). Actual Behavior: When navigating from Page A to Page B: Page A's content script context persists as a "zombie". chrome.tabs.sendMessage(currentTabId, message) reaches zombie context instead of the Page B's one. Hence, it looks like the extension is broken because the content script does not respond to the background messages. Details: Tab ids are properly recognized by both background and content script The problem does not always occur; it occurs on random occasions. It's quite easy to have it reproduced. It can be reproduced easier if user clicks ext icon during site loading (before it fully loaded), triggering ActionClick (ext icon click) event and then sending a msg upon it to the content script Regardless of whether the content script is injected into the tab using manifest.json, registerContentScripts, or executeScript, the problem is still there Once the problem occurs, e.g. user is on macys.com but zombie injected content script believes it's google.com (a previous page), even refreshing the tab doesnt change anything - zombie context is still there (thinking it's still google.com) . Changing a domain to something completely different one could help though. Then going back to macys.com could still lead to the described issue. A zombie content script does not have access to the page's console function and others. Example communication Sending following message from the background to the content script using chrome.tabs.sendMessage() { "tab": { "id": 155, "active": true, "url": "https://www.macys.com/", "title": "Macys.com" } } Results in the content-script zombie context response (the url is taken from the window.location.href) "message": { "type": "ActionClicked", "data": {} }, "response": { "data": { "windowUrl": "https://www.google.com/", "contentReached": true, "timestamp": "1,753,138,945,272", } } }

our company created a web safari extension. before iOS 26 (beta) release we would archive our extension and install to our devices no problem. since iOS 26 (beta) (we also tried in beta 4 23A5297m) the extension would archive perfectly but when installing the extension would just not run. its found in settings under safari extension, but when enabled the extension and open safari it will show error message "Ext" is no longer available. to rule out all code issues, we built a new project from scratch with a new bundle id, tried to archive with no problem, but when installed in an iphone 16 with iOS 26 BETA (23A5297m) same error ocurs it installs but when opening safari it will give an error message saying extension is no longer available. attached in the google drive link is a zip file of the new project, a zip file with a succesfull build of the ipa file with enterprise distribute, a video of the entire proccess and the error that the iphone gives. also attached a log file from the iphone that includes the install and the crash of the app. within the logs there is a log saying Error occurred during transaction: The provided identifier "dev.sacal.ext" is invalid. before ios 26 the exact steps worked perfectly. https://drive.google.com/file/d/1PYDOv8IRvRY_ouqiOc0sJdcfh0CHbL72/view?usp=sharing

I have a hybrid mobile app which loads web server screens in its iframe(which is under the WKWebView); an https request is initiated from the mobile app to the web server which returns the html page to be loaded in the iframe. The calls which are initiated from outside the iframe have cookies maintained in their requests, while the ones initiated from inside the iframe(web server page) loose the cookies and do not inherit them in IOS beta 18 while It worked fine in the previous IOS versions. Anybody has infos about this or similar cases?

It is outrageous that Apple continue to fail to implement the Fullscreen API web standard for web apps on iPhone only, which is so important to accessibility and web app functionality. The only possible reason for this block is commercial: to promote iOS apps instead of browser based web apps. To quote a client from a major agency just now - a typical enquiry : We value accessibility greatly, and we noticed that the embedded player is missing a full screen button on iPhone. Everything else works perfectly fine, including a full screen button that appears on the mobile webpage on android devices. Is there any way we can include a button to enable full screen view for our viewers in your player that are going to watch it on iOS devices? To which, as usual, we have to reply: Apple unfortunately block fullscreen mode from being used with all web applications on iPhone. Apple will allow this to be displayed fullscreen on MacBooks and iPads, but currently not on on iPhone - so we have to hide the fullscreen button there. So fullscreen works on all devices and browsers apart from on iPhone. As you've seen with Android, all other devices and browsers follow the universal 'Fullscreen API' web standard to allow full screen. You're probably familiar with seeing the fullscreen button on normal linear videos on iPhone. These use Apple's native video player, which doesn't let buttons and scripts be used on top of it - just a single video, not an interactive web application. Our player looks like a video player but it is actually a web app combining multiple different video clips connected together by code and styling. They block it on iPhones for reasons known only to them, but the assumption is that it is to incentivise people to make iOS apps instead of web apps. The web development community is hopeful that Apple will change this unfortunate restriction soon, but we have been waiting a long time in vain. We have to send this to a lot of people. It's a very bad look for Apple. In less than a month it will be 2025. We have been waiting years for this. The web standard documentation showing universal support on other devices and browsers is here: https://developer.mozilla.org/en-US/docs/Web/API/Fullscreen_API This is not acceptable. It is time for Apple to stop blocking this important accessibility web standard for commercial reasons - only on iPhone. To whoever is in charge of these decisions in the Safari/Webkit team: Please just enable Fullscreen API for web apps on iPhone as soon as possible.

When I'm inspecting a WKWebView in a simulator and the WKWebView loads a local URL with a port number, I've found that most features of Safari dev tools that worked in iOS 17 are broken in iOS 18. Here are the steps I'm taking: Set up a WKWebView with isInspectable = true that loads a local URL, e.g. https://www.local.mydomain.com:3000 Install a self-signed SSL certificate on a simulator for www.local.mydomain.com Run my app on the simulator The WKWebView loads successfully In Safari on my Mac, I can select the WKWebView and open dev tools to inspect it If the simulator is on iOS 17, this works fine, no issues. But if the simulator is on iOS 18, Safari dev tools are mostly broken. I can tell that there is a connection to the WKWebView because the Network tab logs the requests that I expect. But I cannot use any of the other dev tools features: Elements, Sources, Console, etc. Has anyone else encountered this? Is there a workaround?

Hi all, Chrome has it already - animation-timeline aka scroll-animations. I can nowhere find any informations on what's the status in Safari/Webkit. Seems like they do not have it on the agenda at all? Does anyone know anything - I wanted to push a feature request for that - but also seem there is no feature request list anymore for webkit. See: https://www.w3.org/TR/scroll-animations/ Cheers and kind regards!

We are experiencing an issue with Safari in all versions from 18.0 to 18.5 that does not occur in version 17. It affects both iPhones and Macs. And does not happen in Chrome or Windows. The problem is impacting our customers, and our monitoring tools show a dramatic increase in error volume as more users buy/upgrade to iOS 18. The issue relates to network connectivity that is lost randomly. I can reliably reproduce the issue online in production, as well as on my local development environment. For example our website backoffice has a ping, that has a frequency of X seconds, or when user is doing actions like add to a cart increasing the quantity that requires backend validation with some specific frequency the issue is noticable... To test this I ran a JS code to simulate a ping with a timer that calls a local-dev API (a probe that waits 2s to simulate "work") and delay the next HTTP requests with a dynamic value to simulate network conditions: Note: To even make the issue more clear, I'm using GET with application/json payload to make the request not simple, and require a Pre-flight request, which doubles the issue. (async () => { for (let i = 0; i < 30; i++) { try { console.log(`Request start ${i} ${new Date().toLocaleString()}`); const res = await fetch(`https://api.redated.com:8090/1/*****/probe?`, { method: 'GET', mode: "cors", //headers: {'Content-Type': 'text/plain'}, headers: { 'Content-Type': 'application/json' }, }); console.log(`Request end ${i} ${new Date().toLocaleString()} status:`, res.status); } catch (err) { console.error(`Request ${i} ${new Date().toLocaleString()} error:`, err); } let delta = Math.floor(Math.random() * 10); console.log("wait delta",delta); await new Promise(r => setTimeout(r, 1000 - delta)); } })(); For simplicity lets see a case where it fails 1 time only out of 10 requests. (Adjusting the "delta" var on the time interval create more or less errors...) This are the results: The network connection was lost error, which is false, since this is on my localhost machine, but this happens many times and is very reproducible in local and production online. The dev-tools and network tab shows empty for status error, ip, connection_id etc.. its like the request is being terminated very soon. Later I did a detailed debugging with safari and wireshark to really nail down the network flow of the problem: I will explain what this means: Frame 10824 – 18:52:03.939197: new connection initiated (SYN, ACK, ECE). Frame 10831 – 18:52:04.061531: Client sends payload (preflight request) to the server. Frame 10959 – 18:52:09.207686: Server responds with data to (preflight response) to the client. Frame 10960 – 18:52:09.207856: Client acknowledges (ACK) receipt of the preflight response. Frame 10961 – 18:52:09.212188: Client sends the actual request payload after preflight OK and then server replies with ACK. Frame 11092 – 18:52:14.332951: Server sends the final payload (main request response) to the client. Frame 11093 – 18:52:14.333093: captures the client acknowledging the final server response, which marks the successful completion of the main request. Frame 11146 – 18:52:15.348433: [IMPORTANT] the client attempts to send another new request just one second later, which is extremely close to the keep-alive timeout of 1 second. The last message from the server was at 18:52:14.332951, meaning the connection’s keep-alive timeout is predicted to end around 18:52:15.332951 but it does not. The new request is sent at 18:52:15.348433, just microseconds after the predicted timeout. The request leaves before the client browser knows the connection is closed, but by the time it arrives at the server, the connection is already dead. Frame 11147 – 18:52:15.356910: Shows the server finally sending the FIN,ACK to indicate the connection is closed. This happens slightly later than the predicted time, at microsecond 356910 compared to the expected 332951. The FIN,ACK corresponds to sequence 1193 from the ACK of the last data packet in frame 11093. Conclusions: The root cause is related to network handling issues, when the server runs in a setting of keep-alive behavior and keep-alive timeout (in this case 1s) and network timming issue with Safari reusing a closed connection without retrying. In this situation the browser should retry the request, which is what other browsers do and what Safari did before version 18, since it did not suffer from this issue. This behaviour must differ from previous Safari versions (however i read all the public change logs and could not related the regression change). Also is more pronounced with HTTP/1.1 connections due to how the keep-alive is handled. When the server is configured with a short keep-alive timeout of 1 second, and requests are sent at roughly one-second intervals, such as API pings at fixed intervals or user actions like incrementing a cart quantity that trigger backend calls where the probability of failure is high. This effect is even more apparent when the request uses a preflight with POST because it doubles the chance, although GET requests are also affected. This was a just a test case, but in real production our monitoring tools started to detect a big increment with this network error at scale, many requests per day... which is very disrupting, because user actions are randomly being dropped when the user actions and timming happens to be just near a previous connection, where keep alive timeout kicks-in, but because the browser is not yet notified it re-uses the same connection, but by the time it arrived the server is a dead connection. The safari just does nothing about it, does not even retry, be it a pre-flight or not, it just gives this error. Other browsers don't have this issue. Thanks!

I have noticed that storage.local.get API works differently in Safari 18 compare to other browsers and Safari 17. browser.storage.local.set({abc: 123}) browser.storage.local.get(console.log) // {abc: 123} browser.storage.local.get({abc: null}, console.log) // expect {abc: 123} but got undefined instead. According to MDN, storage.local.get should work with an object with object names as keys and the default value as value. According to Safari 18 Release notes, this may be related to a fix: 'Fixed getting an empty key from storage. (99440265) (FB11427769)'.

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?

This is problematic when opening links to other websites that require separate authentication. A typical example would be a Gmail web app, and then trying to open a link to a GitHub PR. In the 18.0 release notes, this is mentioned as Added support for opening links directly in web apps on macOS. (113034778 It'd be great if this could be customizable so that one could choose the old behavior.