The crash is specific to iOS 26.2 prior versions working fine.
WKScriptMessageHandler delegate func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage)
Name attribute is accessible but WKScriptMessage body attribute causes crash
The object seems to be not accessible(not in memory)
self.webkit.configuration.userContentController.add(self, name: "sampleHandler")
self.webkit.load(request)
func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
print(message.name) // works print(message.body) // crashes
}
Explore the integration of web technologies within your app. Discuss building web-based apps, leveraging Safari functionalities, and integrating with web services.
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I have a local HTML file used to display mixed content with images and text. Here's the issue: the same file displays everything correctly in Google Chrome, showing both images and text as expected. However, when opened in Safari, only the text is shown—images are missing, which is very strange.
Interestingly, if I remove .png from the title attribute of the tag, the images show up properly in Safari. Alternatively, if I comment out the inclusion of html2canvas.min.js, the images also display correctly (although the layout breaks without it).
I'm not sure if this is a Safari-specific issue. Can anyone explain what might be causing this problem?
Topic:
Safari & Web
SubTopic:
General
I have a simple Safari extension for iOS.
In its popup, I want a button that will open the app via a universal link.
I have this kind-of working, except that Safari opens the actual online destination of the link with a banner at the top saying "Open in the XXXX app" and an OPEN button.
What do I have to do to go directly to the app?
More generally, I know that if I copy-and-paste a universal link into the Safari address bar, Safari does the same thing - but it does go directly to the app from an <a href="...."> link.
In my app extension JavaScript, I set window.location. Presumably this is too similar to pasting into the address bar.
Is there some alternative to setting window.location that is more like clicking on a link and will go directly to the universal link's app?
Thanks.
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 am posting here because we have an urgent issue affecting the operation of our service and are in need of a solution after our own analysis has come up with few answers.
Beginning in iOS 18.2.x, we experienced exactly the same issue as the author of this thread, as we are also operating a service that allows for device certificate login for users configured to require one:
https://developer.apple.com/forums/thread/767374
The author seems to have resolved the issue but the fix mentioned in the thread did not resolve our problem for iOS devices with iOS 18.2.x installed and the contents of that private support ticket are, of course, not visible to us. Furthermore, we have a different issue that surfaced with the release of iOS 18.3.x.
Namely, the issue in iOS 18.3.x is more severe than the one in iOS 18.2.x, in that instead of simply taking a long time for the certificate/identity selection dialog to appear, it simply fails immediately and is returning a “no certificate selected” response to our server.
One thing to note here is that, curiously, if we wait for several seconds (about 10-15 seconds) this behavior is not replicated. So, it seems there is potentially something going in the background, and the certificate selection process will only occur successfully like before if we wait. This is a very unideal workaround.
After entering user credentials, we have the user navigate to a dedicated certificate authentication page. On the BIG IP side, upon users visiting this page, we have it configured to apply an SSL profile that contains appropriate CAs for the given user, and then requests to the browser that a new connection requiring a certificate be made.
We are investigating this by checking logs in in a variety of places:
We can verify in BigIP logs that a response is being returned to the server without a certificate included. For the sake of our application, this is handled as a “user did not select a certificate” event, and thus the attempted login is failed. Using the MacOS “Console” application, we are able to see the following logs from the “trustd” process of the target iOS 18.3.x device:
Failure case:
debug 11:19:49.648581+0900 trustd XPC [com.apple.WebKit[1034]/1#25 LF=0] operation: trust_evaluate (8)
debug 11:19:49.648766+0900 trustd complex trust settings anchor
Successful case (after waiting 10-15 seconds after initial login page load/before moving to certificate page):
debug 11:26:02.803153+0900 trustd XPC [MobileSafari[1031]/1#169 LF=0] operation: trust_evaluate (8)
debug 11:26:02.804219+0900 trustd non ev score: 121 <private>
There appears to be no attempt by MobileSafari to initiate the display of a certificate selection window in the failure cases. The iOS device is swift to return a response with no certificate selected to Big IP, and the result of “no certificate selected” is thus propagated through Big IP and ultimately to our web service.
Does anyone have any advice or information on the following?
Recommended tools to gather more data that may be pertinent.
Any ideas on changes in iOS 18.2.x+ that could have resulted in the behavior changing as described above?
If more information is necessary, I will do my best to supply it. Thank you in advance!
Topic:
Safari & Web
SubTopic:
General
Trying to implement my own forward/back buttons for the new SwiftUI WebView and reading the documentation I’m totally lost.
What’s the recommended way of implementing forward/back behavior with this component?
I am encountering an intermittent issue with WKWebView in my iOS app. The problem occurs infrequently, but when it does, the WKWebView consistently displays a white screen and remains in this state until the app is forcefully terminated and relaunched.
To provide more context, here are the key characteristics of the issue:
The white screen problem occurs sporadically and is not easily reproducible.
The WKWebView remains unresponsive despite attempts to interact with it.
Reloading the webpage or navigating to a different URL does not resolve the white screen issue.
The problem persists until the app is terminated and relaunched.
This issue is specific to the WKWebView; other components of the app function correctly.
The WKWebView renders normally, and the main document synchronously loads resources both offline and online without any issues. The bridge and JavaScript execution also work as expected.
However, when interacting with the WKWebView, it becomes unresponsive to user clicks, and the web inspector fails to respond. Additionally, asynchronous network requests also do not receive any response.
The problem occurs exclusively on HTTPS pages, whereas HTTP pages load without any issues. Other components, such as workers, function correctly.
addUserScript injection during WKWebView creation is effective, and evaluateJavaScript during the page loading process works as expected. However, when the document becomes unresponsive, executing evaluateJavaScript only triggers the callback after the WKWebView is destroyed.
I have discovered a reliable method to reproduce the white screen issue in WKWebView. This method involves the following steps and conditions:
Create a WKWebView instance.
Load an HTML page using the loadRequest method(https url request).
Before the WKWebView is attached to the UI (not yet visible to the user), call the evaluateJavaScript function.
This issue has occurred in almost all iOS versions, including the latest iOS 17.x version.
I am trying to setup web sign in with apple, I have an active apple subscription and have set up all necessary things. I made a service id in apple Identifiers, connected to existing primary id (also has apple sign in enabled). I have my domain set up also correctly but still I cant generate the code due to invalid client. What do I need to do?
I have also tried recreating the service ids multiple times with no luck.
my init is
AppleID.auth.init({
clientId : '[CLIENT_ID]',//used the service id one not app id
redirectURI : '[REDIRECT_URI]',
usePopup : true
});
link to generate codes now is: https://appleid.apple.com/auth/authorize?client_id=com.crmtournest.sigin&redirect_uri=https%3A%2F%2Fwww.tournestcrm.com%2Fauth%2Fcallback&response_type=code%20id_token&state=saciy7rn1km&scope=name%20email&response_mode=web_message&frame_id=03487c22-abb4-48cd-8613-d6bf5836e9eb&m=11&v=1.5.5
Also tried: https://appleid.apple.com/auth/authorize?client_id=com.crmtournest.sigin&redirect_uri=https%3A%2F%2Fwww.tournestcrm.com%2Fauth%2Fcallback&response_type=code%20id_token (not working)
I get invalid_client
setup on apple below:
The passkey authentication dialog appears, and after unlocking with Touch ID, the dialog closes without any notification of success or failure.
This issue occurs with high frequency.
access to the https://passkeys-demo.appspot.com/
register account and create passkey.
logoff
access to the url again
you can see the passkey dialog
unlock device then the dialog disappears
nothing happens
reload the page
proceed 5) to 6)
nothing happens or success webauthn.
Topic:
Safari & Web
SubTopic:
General
Tags:
WebKit JS
WebKit
Safari and Web
Passkeys in iCloud Keychain
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.
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
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?
使用direct distribution进行分发时,safari web extension 在safari setting 中显示没有权限读取、修改或传输任何网页的内容。
但是我在看公证日志显示插件是正常的公证的
这导致safari extension 无法使用。
公证日志
https://www.coupert.com/img/2025-04-10/notarization-log.json
Safari 18.0.1 on macOS 15.01 doesn't support the Passkey PRF extension during cross-device WebAuthn authentication when using QR code scanning, while it works correctly with iCloud passkeys.
Steps to Reproduce:
Clone and setup:
git clone https://github.com/quocle108/passkey-prf-test
yarn
yarn start
Test iCloud Passkey Flow:
Open http://localhost:3000 in Safari
Open DevTools (Cmd+Option+I)
Click "Register"
Choose "Passkey on iCloud"
Expected console output: PRF supported: true
Test Cross-Device Flow:
Click "Register"
Choose "Phone/Tablet"
Scan QR with mobile device
Expected: PRF supported: true
PRF extension should be supported in cross-device flow, matching iCloud passkey behavior.
Actual: PRF supported: false
Cross-device flow returns empty extension results.
Verify in Chrome
Repeat steps 2-3 in Chrome
Both flows return proper PRF extension results: PRF supported: true
Test Environment:
Browser: Safari 18.1.1 , Chrome 131.0.6778.70
OS: macOS 15.01
Mobile: iOS 18.x / Galaxy Note9 Android 10
Test repo: https://github.com/quocle108/passkey-prf-test
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.
Hi Apple engineers!
We are making an iOS browser and are planing to deliver a feature that allows enterprise customers to use a MAM key to set a PAC file for proxy. It's designed to support unmanaged device so the MDM based solutions like 'Global HTTP Proxy MDM payload' or 'Per-App VPN' simply don't work.
After doing some research we found that with WKWebView, the only framework allowed on iOS for web browsing, there's no API for programmatically setting proxy. The closes API is the WKURLSchemeHandler, but it's for data management not network request interception, in other word it can not be used to handle HTTP/HTTPS request well.
When we go from the web-view level to the app level, it seems there's no API to let an app set proxy for itself at an app-level, the closest API is Per-App VPN but as mentioned above, Per-App VPN is only available for managed device so we can't use that as well.
Eventually we go to the system level, and try to use Network Extension, but there's still obstacles. It seems Network Extension doesn't directly provide a way to write system proxy. In order to archive that, we may have to use Packet Tunnel Provider in destination IP mode and create a local VPN server to loop back the network traffic and do the proxy stuff in that server. In other word, the custom VPN protocol is 'forward directly without encryption'. This approach looks viable as we see some of the network analysis tools use this approach, but still I'd like to ask is this against App Store Review Guidelines?
If the above approach with Network Extension is not against App Store Review Guidelines, I have a further question that, what is the NEProxySettings of NETunnelNetworkSettings for? Is it the proxy which proxies the VPN traffic (in order to hide source IP from VPN provider) or it is the proxy to use after network traffic goes into the virtual private network?
If none of the above is considered recommended, what is the recommended way to programmatically set proxy on WKWebView on an unmanaged device (regardless of where the proxy runs, web-view/app/system)?
I'm a web developer of WebRTC based web app for video and audio calls. After updating to iOS 26.1 beta I noticed, that my app can't use microphone anymore.
When I'm calling to getUserMedia with audio set to true, Safari returns error "No AVAudioSessionCaptureDevice device".
Other WebRTC demo apps also can't access microphone on this firmware.
And maybe it's connected somehow, but safari can't detect connected AirPods Pro 2 as an input device.
So, this bug brakes any WebRTC app, that uses microphones.
This is a rare occurrence on our site, having only detected 4 instances of it over the past few weeks, where 10s of thousands of transactions have occurred successfully.
We only call the following PaymentRequest API onClick from the <apple-pay-button>:
async function startApplePay(merchantIdentifier, amount) {
...
try {
const request = new PaymentRequest([ applePayMethod ], paymentDetails);
...
catch (e) {
// cancel, just stay here
if (e.name === "AbortError") {
if (consoleLog) console.log("Payment canceled", e);
logServer("INFO", "Payment canceled");
}
else {
handleError("Error caught: " + e.name + ", " + e.cause + ", " + e.message);
}
}
Where the "handleError" else case is what gets triggered:
Error caught: SecurityError, undefined, show() must be triggered by user activation.
All 4 instances have been from iPads, but with that small of a sample size, we can't tell whether that's relevant or coincidence. Different iOS versions, but looks like same Safari version.
Here are the 4 User Agents we've seen thus far:
Mozilla/5.0 (iPad; CPU OS 18_2_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) GSA/352.0.715618234 Mobile/15E148 Safari/604.1
Mozilla/5.0 (iPad; CPU OS 17_6_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) GSA/352.0.715618234 Mobile/15E148 Safari/604.1
Mozilla/5.0 (iPad; CPU OS 18_3_0 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/133.0.6943.33 Mobile/15E148 Safari/604.1
Mozilla/5.0 (iPad; CPU OS 18_2_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/133.0.6943.33 Mobile/15E148 Safari/604.1
iPadOS 26, dark mode
Open Safari
Search for anything or open a website that has white background
Kill Safari
Open Safari again
I still can reproduce it with Safari on iPadOS 26.0.1
This issue also happens to my app when opening a HTML/JS on WKWebView with white background while using dark mode. I did send a feedback ticket when using iPadOS 26 beta but havent seen any reply. This is my first time sending a feedback so I dont know if Apple would reply or not.
The crash is specific to iOS 26.2 WKScriptMessageHandler delegate func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage)
Name attribute is accessible but WKScriptMessage body attribute causes crash
The object seems to be not accessible