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.
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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From a mail app or similar, when opening a webpage in Safari as an external browser, JavaScript on the webpage stops running if Safari goes into the background. Is there a way to prevent this from happening?
Sample code for the counter:
Behavior: Upon returning from the background, the counter continues for about 7-8 seconds but does not progress further.
For example, if Safari is kept in the background for about 20 seconds and then brought back, the counter stops at around 7-8 seconds and only resumes counting after returning to the foreground.
Expectation: The counter should continue running even if Safari goes into the background.
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
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.
Sometimes Safari is rendering the icon for an active extension in its original provided colored representation, other times Safari is applying an overlay color in line with the system's highlight color.
This difference can even be seen seen on the Safari Extensions Developer home page: https://developer.apple.com/safari/extensions/images/extensions-hero-large_2x.png
You will notice that Grammarly's icon is shown in it's original color format, while the others aren't.
Example of extensions where the icon is shown in color:
Bitwarden
Grammarly
1Password
Consent-O-Matic
I've compared the source code of Bitwarden and Consent-o-Matic with my own extension and cannot find any differences in the settings or image properties (resolution, DPI, file type, color profile). If I take the exact PNG source files from said open source extensions and replace them in my own source code, these icons show up in full color.
Does this perhaps mean there is a bug in Safari's processing of the icons where it fails to overlay the icon with the highlight color in some cases?
I and I assume many developers with me would like to understand what determines this difference. Ideally, there is a consistent UX where the end user has the choice between icons in color or highlight color overlay.
Is it possible to open the native app from a web extension?
I have tried creating a new tab that uses the app's URL scheme but the UI asking the user to open the app is not shown until the new page UI is dismissed.
Creating a tab with an HTTPS URL that the app is setup to handle does not work and always the link in a new tab.
I tried sending a message to the app extension and using NSExtensionContext.open(_:completionHandler:) but the URL is not opened and the closure received false, indicating it was not handled.
Having the option to link back to the native app would be very useful.
As with the adoption of MV3 standards among all major browser vendors that allow browser extensions at the client-side, I understand that this is the same with Safari as well, as mentioned here (https://www.wwdcnotes.com/notes/wwdc22/10099/). However, as with Firefox, browsers may choose to adopt them incompletely and with few changes. I had a few questions regarding how Safari views this transition and what would be the next steps from here.
Thus, it would be really great if the browser team could provide your insights on any or all of the following points:
Would Safari adopt the exact standards proposed by the Chromium ecosystem such as with functionalities like header-based modifications in the coming days.
What would be the general timeline be for this in general?
Does this also translate to the fact that existing standards with MV2 standards would not be allowed to operate any further, as with the timeline with Chromium?
Regards
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 !
Background
On iOS 18.4 beta, setting a content inset on a WKWebView causes touch events inside the web view to be offset by the content inset amount. In other words, if the web view has a top content inset of 75 points, I must tap 75 points above the intended element for the touch to register correctly. This makes any web content unusable when a content inset is present.
A sample app demonstrating the issue is available here: GitHub - iOS18.4-Webview-Bug.
The issue does not occur in iOS 18.3 or 18.2.
Bug Report
The bug has been reported and fixed at WebKit Bug 289715 and also filed as rdar://147075945.
Question
Will the fix be included in the upcoming iOS 18.4 beta release (Beta 5) or soon thereafter?
I want to migrate from a Safari App Extension to a Safari Web Extension, but don't know how to get rid of the message, telling users that my extension can access their passwords. Here is a message which I see:
I was thinking that this might be because all Safari Web Extension get this type of access, but I have a Safari Web Extension which does not require such level of access:
Here is the manifest:
{
"manifest_version": 2,
"default_locale": "en",
"name": "__MSG_extension_name__",
"description": "__MSG_extension_description__",
"version": "1.1",
"icons": {
"48": "images/icon-48.png"
},
"background": {
"scripts": [
"background.js"
],
"persistent": true
},
"browser_action": {
"default_popup": "popup.html",
"default_icon": {
"16": "images/toolbar-icon-16.png"
}
},
"permissions": [
"nativeMessaging", "tabs"
]
}
and here is the Info.plist file:
Here is the entire code of the extension:
https://github.com/kopyl/web-extension-simplified
Hello,
I'm not able to get the webauthn attestation statement using the option (attestation.direct) on Safari. The answer I get is a fmt of none and a aaguid of zeros.
The same code works on Chrome and I was able to get a none zero aaguid and a packed fmt attestation.
Can you explain why this does not work on Safari ?
Thank you.
The application I'm currently working on uses WebKit. Based on the crash analytics, we have noticed that some of our users are experiencing an unusual behavior in the app's WebKit view with macOS 15.3.2. These errors are reported for this version of the OS. The error in the crash log is a SIGABRT error, but there is no relevant information available to address it. In some crash logs, we found this error: "NSInternalInconsistencyException: Returned WKWebView was not created with the given configuration" but there is not any particular way to address it. Is there a way to identify the cause of this error? Alternatively, has anyone encountered this issue and found a solution?
OS Version: macOS 15.3.2 (24D81)
Report Version: 104
Exception Type: EXC_CRASH (SIGABRT)
Crashed Thread: 0
Application Specific Information:
Returned WKWebView was not created with the given configuration.
Thread 0 Crashed:
0 CoreFoundation 0x303111e74 __exceptionPreprocess
1 libobjc.A.dylib 0x3027b6cd4 objc_exception_throw
2 CoreFoundation 0x303111d6c +[NSException raise:format:]
3 WebKit 0x34e85cb20 WebKit::UIDelegate::UIClient::createNewPage
4 WebKit 0x34e8a4a80 WebKit::SOAuthorizationCoordinator::tryAuthorize
5 WebKit 0x34e9f04f8 WebKit::WebPageProxy::createNewPage
6 WebKit 0x34ef994c8 WebKit::WebPageProxy::didReceiveSyncMessage
7 WebKit 0x34f0830cc IPC::MessageReceiverMap::dispatchSyncMessage
8 WebKit 0x34ea753b0 WebKit::WebProcessProxy::didReceiveSyncMessage
9 WebKit 0x34f07cfb4 IPC::Connection::dispatchSyncMessage
10 WebKit 0x34f07d3b0 IPC::Connection::dispatchMessage
11 WebKit 0x34f078c50 IPC::Connection::SyncMessageState::ConnectionAndIncomingMessage::dispatch
12 WebKit 0x34f07f4f4 ***::Detail::CallableWrapper<T>::call
13 JavaScriptCore 0x33f3520c0 ***::RunLoop::performWork
14 JavaScriptCore 0x33f352fe8 ***::RunLoop::performWork
15 CoreFoundation 0x30309f8a0 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__
16 CoreFoundation 0x30309f834 __CFRunLoopDoSource0
17 CoreFoundation 0x30309f598 __CFRunLoopDoSources0
18 CoreFoundation 0x30309e134 __CFRunLoopRun
19 CoreFoundation 0x30309d730 CFRunLoopRunSpecific
20 HIToolbox 0x319aeb52c RunCurrentEventLoopInMode
21 HIToolbox 0x319af1344 ReceiveNextEventCommon
22 HIToolbox 0x319af1504 _BlockUntilNextEventMatchingListInModeWithFilter
23 AppKit 0x30a7cd844 _DPSNextEvent
24 AppKit 0x30b133c20 -[NSApplication(NSEventRouting) _nextEventMatchingEventMask:untilDate:inMode:dequeue:]
25 AppKit 0x30a7c0870 -[NSApplication run]
26 AppKit 0x30a797064 NSApplicationMain
27 <unknown> 0x182780274 <redacted>
Thread 0 name: t-main-ui Crashed:
0 CoreFoundation 0x303111e74 __exceptionPreprocess
1 libobjc.A.dylib 0x3027b6cd4 objc_exception_throw
2 CoreFoundation 0x303111d6c +[NSException raise:format:]
3 WebKit 0x34e85cb20 WebKit::UIDelegate::UIClient::createNewPage
4 WebKit 0x34e8a4a80 WebKit::SOAuthorizationCoordinator::tryAuthorize
5 WebKit 0x34e9f04f8 WebKit::WebPageProxy::createNewPage
6 WebKit 0x34ef994c8 WebKit::WebPageProxy::didReceiveSyncMessage
7 WebKit 0x34f0830cc IPC::MessageReceiverMap::dispatchSyncMessage
8 WebKit 0x34ea753b0 WebKit::WebProcessProxy::didReceiveSyncMessage
9 WebKit 0x34f07cfb4 IPC::Connection::dispatchSyncMessage
10 WebKit 0x34f07d3b0 IPC::Connection::dispatchMessage
11 WebKit 0x34f078c50 IPC::Connection::SyncMessageState::ConnectionAndIncomingMessage::dispatch
12 WebKit 0x34f07f4f4 ***::Detail::CallableWrapper<T>::call
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,
Topic:
Safari & Web
SubTopic:
General
On iOS 26 Beta, WKWebView consistently crashes when interacting with pages that use -webkit-user-select: none.
This issue does not reproduce in Safari, but only when the same content is loaded inside a WKWebView.
Steps to Reproduce:
Install iOS 26 Beta.
Open a WKWebView that loads a webpage with the following style applied globally:
-webkit-user-select: none;
Perform the following gesture sequence inside the WKWebView:
Double tap anywhere in the web content.
On the second tap, keep your finger pressed (do not lift).
While still holding the second tap, drag your finger across the screen (pan).
This sequence reliably produces the crash.
Expected Result:
No crash. The gesture should either be ignored or handled gracefully.
Actual Result:
The app crashes 100% of the time with the following exception:
#0 0x000000013f1a0874 in __pthread_kill ()
#1 0x00000001357522ec in pthread_kill ()
#2 0x00000001801ad950 in abort ()
#3 0x00000001802fa26c in __abort_message ()
#4 0x00000001802ea1a4 in demangling_terminate_handler ()
#5 0x0000000180077218 in _objc_terminate ()
#6 0x00000001802f9758 in std::__terminate ()
#7 0x00000001802fc7c0 in __cxxabiv1::failed_throw ()
#8 0x00000001802fc7a0 in __cxa_throw ()
#9 0x000000018009c1bc in objc_exception_throw ()
#10 0x00000001804f38f8 in +[NSException raise:format:] ()
#11 0x000000018c5fb570 in -[CALayer setPosition:] ()
#12 0x0000000185d02414 in -[UIView _backing_setPosition:] ()
#13 0x00000001867ec978 in -[UIView setCenter:] ()
#14 0x0000000186666468 in -[_UIEditMenuContentPresentation _displayPreparedMenu:titleView:reason:didDismissMenu:configuration:] ()
#15 0x0000000186666088 in __54-[_UIEditMenuContentPresentation _displayMenu:reason:]_block_invoke ()
#16 0x00000001867b3ed4 in -[UIEditMenuInteraction _editMenuPresentation:preparedMenuForDisplay:completion:] ()
#17 0x0000000186665fb0 in -[_UIEditMenuContentPresentation _displayMenu:reason:] ()
#18 0x0000000186665de4 in -[_UIEditMenuContentPresentation displayMenu:configuration:] ()
#19 0x00000001867b3260 in __58-[UIEditMenuInteraction presentEditMenuWithConfiguration:]_block_invoke ()
#20 0x00000001867b4c98 in __80-[UIEditMenuInteraction _prepareMenuAtLocation:configuration:completionHandler:]_block_invoke ()
#21 0x000000018653ff80 in __109-[UITextContextMenuInteraction _editMenuInteraction:menuForConfiguration:suggestedActions:completionHandler:]_block_invoke ()
#22 0x0000000186540448 in __107-[UITextContextMenuInteraction _querySelectionCommandsForConfiguration:suggestedActions:completionHandler:]_block_invoke ()
#23 0x000000018dba84f8 in WTF::Detail::CallableWrapper<WTF::CompletionHandler<void (IPC::Connection*, IPC::Decoder*)> IPC::Connection::makeAsyncReplyCompletionHandler<Messages::WebPage::RequestDocumentEditingContext, WTF::CompletionHandler<void (WebKit::DocumentEditingContext&&)>>(WTF::CompletionHandler<void (WebKit::DocumentEditingContext&&)>&&, WTF::ThreadLikeAssertion)::'lambda'(IPC::Connection*, IPC::Decoder*), void, IPC::Connection*, IPC::Decoder*>::call ()
#24 0x000000018dca14cc in WTF::Detail::CallableWrapper<WebKit::AuxiliaryProcessProxy::sendMessage(WTF::UniqueRef<IPC::Encoder>&&, WTF::OptionSet<IPC::SendOption>, std::__1::optional<IPC::ConnectionAsyncReplyHandler>, WebKit::AuxiliaryProcessProxy::ShouldStartProcessThrottlerActivity)::$_1, void, IPC::Connection*, IPC::Decoder*>::call ()
#25 0x000000018e2d5c54 in IPC::Connection::dispatchMessage ()
#26 0x000000018e2d6118 in IPC::Connection::dispatchIncomingMessages ()
#27 0x00000001997f9c58 in WTF::RunLoop::performWork ()
#28 0x00000001997fa930 in WTF::RunLoop::performWork ()
#29 0x000000018044d4dc in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ ()
#30 0x000000018044d424 in __CFRunLoopDoSource0 ()
#31 0x000000018044cc0c in __CFRunLoopDoSources0 ()
#32 0x000000018044bd84 in __CFRunLoopRun ()
#33 0x0000000180446e24 in _CFRunLoopRunSpecificWithOptions ()
#34 0x00000001924c19bc in GSEventRunModal ()
#35 0x00000001862217a8 in -[UIApplication _run] ()
#36 0x00000001862259d0 in UIApplicationMain ()
Same issues below.
https://developer.apple.com/forums/thread/796799
https://developer.apple.com/forums/thread/796501
https://developer.apple.com/forums/thread/796874
https://developer.apple.com/forums/thread/796686
Up until some point relatively recently, I have been able to use Safari's web inspector to connect to the iOS simulator in order to debug our web application in development at http://localhost:8088.
Now, the web inspector still OPENS, but it opens in a broken state. The context is available to select from Safari's "Develop" menu: Develop > "iPhone 16 Pro (Simulator)" > "localhost - login". It appears under the Safari heading if I have navigated to the web app in the browser, or under the Expo heading if I am accessing it through the webview in our React Native wrapper app. When I select it, the web inspector window does appear.
However, once it opens, the Elements pane is empty, the Console pane is empty, expressions entered into the console are not evaluated, there's no content in Sources, Network, Storage, etc.
Important notes:
This broken state happens at http://localhost:8088 as well as http://127.0.0.1:8088, and it seems that the insecure context is the issue.
The web inspector DOES work for HTTPS sites. If I navigate to, e.g., https://example.com in the simulator and connect the web inspector, everything works fine.
The web inspector also works fine in Safari on macOS (OUTSIDE the simulator) when accessing non-HTTPS sites. It's only a problem for non-HTTPS sites when connecting to the simulator.
A coworker has the same problem, so it is not isolated to my machine.
I would enable TLS locally as a workaround, but this web app is very complex, and I know from experience that it is very difficult for various reasons to set it up properly for our project in development, and it will take significant non-trivial work to do so.
So... Why is this happening? Is this expected behavior? Is there a way that I can debug my site on localhost without HTTPS?
I am encountering an issue where we are unable to run or launch Safari Driver in our automation tests using macOS. When attempting to run safaridriver -p 8888 from the terminal, we receive the following error message:
ERROR: safaridriver could not launch because it is not configured correctly or you need to authenticate. Re-run safaridriver(1) and pass the '--enable' flag to configure and/or authenticate.
For more information, consult the safaridriver(1) man page.
Despite running sudo safaridriver --enable as an administrator (even as root), the issue persists.
I’ve searched through various online forums and GitHub repositories but couldn’t find a working solution. Some references are:
Apple Developer Forum Thread: https://forums.developer.apple.com/forums/thread/762321
GitHub Issue: https://github.com/SeleniumHQ/selenium/issues/11381
After upgrading to Safari version 18, we encountered an issue with my extension’s background script not being able to access cookies. Previously, in Safari versions 17 and below, the extension worked as expected. Now, when the extension tries to retrieve cookies using browser.cookies.getAll(), it returns an empty list. However, if we open the extension’s developer tools, the cookies are visible and accessible.
It seems that Safari only provides cookie data after the developer tools have been opened. However, after relaunching Safari and launching the extension without opening the developer tools, browser.cookies.getAll() still returns an empty list.
Has anyone else experienced this?
STEPS TO REPRODUCE
Download this minimal app : https://www.icloud.com/iclouddrive/0bajlhnuQaG6T5NsFKXEB0U9Q#test%5Fcookies
Compile test_mv2 extension (in test_cookies.getAll.zip).
Launch test_mv2.app and activate extension.
Click on the extension's button (browserAction).
Open the developer tools.
Observe an empty list of cookies.
Click on the extension's button (browserAction).
Cookies are retrieved as expected.
Is this code invalid on a phone running xcode16 iOS18?
Class cls = NSClassFromString(@"WKBrowsingContextController");
SEL sel = NSSelectorFromString(@"registerSchemeForCustomProtocol:");
if ([(id)cls respondsToSelector:sel]) {
[(id)cls performSelector:sel withObject:@"http"];
[(id)cls performSelector:sel withObject:@"https"];
}
}
Topic:
Safari & Web
SubTopic:
General
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
Reproducibility
100% on iOS 15.4 and iOS 16.6
Zero crash on iOS 18.6
Xcode
26.1
Steps to Reproduce
Xcode 26.1 → New iOS App
Replace ViewController.swift with the 20-line code below
Run on real device
• iPhone XR iOS 15.4
• iPhone 13 iOS 16.6
Tap the link → breakpoint in decidePolicyFor
lldb → po navigationAction.sourceFrame
Actual Result
(lldb) po navigationAction.sourceFrame
nil
Swift declaration lies:
public var sourceFrame: WKFrameInfo { get } // non-optional
→ Instant EXC_BREAKPOINT
libswiftFoundation.dylib`URLRequest._unconditionallyBridgeFromObjectiveC
Objective-C tells the truth:
po [(WKNavigationAction *)navigationAction fixedSourceFrame]
nil
iOS 18.6 → same code prints a valid WKFrameInfo, no crash.
Expected
sourceFrame must be declared WKFrameInfo? in Swift
or at least documented “can be nil on iOS 15–16”.
Impact
Every WKWebView app that touches sourceFrame on iOS 15.4 & 16.6 ships with a latent crash.
Production Workaround
@implementation WKNavigationAction (Safe)
(WKFrameInfo *)fixedSourceFrame {
return self.sourceFrame ? self.sourceFrame : nil;
}
@end
Minimal Test (copy-paste)
import UIKit
import WebKit
class ViewController: UIViewController, WKNavigationDelegate {
lazy var web = WKWebView(frame: view.bounds)
override func viewDidLoad() {
super.viewDidLoad()
web.navigationDelegate = self
view.addSubview(web)
web.load(URLRequest(url: URL(string: "https://www.apple.com")!))
}
func webView(_ webView: WKWebView,
decidePolicyFor navigationAction: WKNavigationAction,
preferences: WKWebpagePreferences,
decisionHandler: @escaping (WKNavigationActionPolicy, WKWebpagePreferences)->Void) {
print(navigationAction.sourceFrame) // ← crashes on 15.4 & 16.6
decisionHandler(.allow, preferences)
}
}