The following two API tests are asserting on iOS at/around https://commits.webkit.org/256747@main

TestWebKitAPI.WKWebExtensionController.BackgroundPageLoading
TestWebKitAPI.WKWebExtensionController.BackgroundPageWithModulesLoading

        ASSERTION FAILED: !m_messageReceivers.contains(std::make_pair(messageReceiverName, destinationID))
        /Volumes/Data/worker/Apple-iOS-16-Simulator-Debug-Build/build/Source/WebKit/Platform/IPC/MessageReceiverMap.cpp(53) : void IPC::MessageReceiverMap::addMessageReceiver(IPC::ReceiverName, uint64_t, IPC::MessageReceiver &)
        1   0x808bbe459 WTFCrash
        2   0x7e9efee7b WTFCrashWithInfo(int, char const*, char const*, int)
        3   0x7ecc84554 IPC::MessageReceiverMap::addMessageReceiver(IPC::ReceiverName, unsigned long long, IPC::MessageReceiver&)
        4   0x7eb3e9935 WebKit::AuxiliaryProcess::addMessageReceiver(IPC::ReceiverName, unsigned long long, IPC::MessageReceiver&)
        5   0x7ebe5e577 void WebKit::AuxiliaryProcess::addMessageReceiver<WebKit::WebExtensionContextIdentifierType>(IPC::ReceiverName, WTF::ObjectIdentifier<WebKit::WebExtensionContextIdentifierType>, IPC::MessageReceiver&)
        6   0x7ebe5e4e1 WebKit::WebExtensionContextProxy::WebExtensionContextProxy(WebKit::WebExtensionContextParameters)
        7   0x7ebe5e335 WebKit::WebExtensionContextProxy::WebExtensionContextProxy(WebKit::WebExtensionContextParameters)
        8   0x7ebe5e0db WebKit::WebExtensionContextProxy::getOrCreate(WebKit::WebExtensionContextParameters)
        9   0x7ebe5f198 WebKit::WebExtensionControllerProxy::load(WebKit::WebExtensionContextParameters const&)
        10  0x7ec5c95e7 void IPC::callMemberFunctionImpl<WebKit::WebExtensionControllerProxy, void (WebKit::WebExtensionControllerProxy::*)(WebKit::WebExtensionContextParameters const&), std::__1::tuple<WebKit::WebExtensionContextParameters>, 0ul>(WebKit::WebExtensionControllerProxy*, void (WebKit::WebExtensionControllerProxy::*)(WebKit::WebExtensionContextParameters const&), std::__1::tuple<WebKit::WebExtensionContextParameters>&&, std::__1::integer_sequence<unsigned long, 0ul>)
        11  0x7ec5c8a3d void IPC::callMemberFunction<WebKit::WebExtensionControllerProxy, void (WebKit::WebExtensionControllerProxy::*)(WebKit::WebExtensionContextParameters const&), std::__1::tuple<WebKit::WebExtensionContextParameters>, std::__1::integer_sequence<unsigned long, 0ul> >(std::__1::tuple<WebKit::WebExtensionContextParameters>&&, WebKit::WebExtensionControllerProxy*, void (WebKit::WebExtensionControllerProxy::*)(WebKit::WebExtensionContextParameters const&))
        12  0x7ec5c82e6 void IPC::handleMessage<Messages::WebExtensionControllerProxy::Load, WebKit::WebExtensionControllerProxy, void (WebKit::WebExtensionControllerProxy::*)(WebKit::WebExtensionContextParameters const&)>(IPC::Connection&, IPC::Decoder&, WebKit::WebExtensionControllerProxy*, void (WebKit::WebExtensionControllerProxy::*)(WebKit::WebExtensionContextParameters const&))
        13  0x7ec5c80e3 WebKit::WebExtensionControllerProxy::didReceiveMessage(IPC::Connection&, IPC::Decoder&)
        14  0x7ecc85d93 IPC::MessageReceiverMap::dispatchMessage(IPC::Connection&, IPC::Decoder&)
        15  0x7ebe03d31 WebKit::WebProcess::didReceiveMessage(IPC::Connection&, IPC::Decoder&)
        16  0x7ecc57c8f IPC::Connection::dispatchMessage(IPC::Decoder&)
        17  0x7ecc5805a IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >)
        18  0x7ecc583cd IPC::Connection::dispatchOneIncomingMessage()
        19  0x7ecc7a68d IPC::Connection::enqueueIncomingMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >)::$_17::operator()() const
        20  0x7ecc7a5d9 WTF::Detail::CallableWrapper<IPC::Connection::enqueueIncomingMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >)::$_17, void>::call()
        21  0x808bee552 WTF::Function<void ()>::operator()() const
        22  0x808c8eebe WTF::RunLoop::performWork()
        23  0x808c9445e WTF::RunLoop::performWork(void*)
        24  0x7d11f4ebd __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__
        25  0x7d11f4dfc __CFRunLoopDoSource0
        26  0x7d11f45f9 __CFRunLoopDoSources0
        27  0x7d11eedb3 __CFRunLoopRun
        28  0x7d11ee637 CFRunLoopRunSpecific
        29  0x7d390a9fc -[NSRunLoop(NSRunLoop) runMode:beforeDate:]
        30  0x7d390ac1a -[NSRunLoop(NSRunLoop) run]
        31  0x7d2095e3f _xpc_objc_main
        ASSERTION FAILED: !m_backgroundWebView
        /Volumes/Data/worker/Apple-iOS-16-Simulator-Debug-Build/build/Source/WebKit/UIProcess/Extensions/Cocoa/WebExtensionContextCocoa.mm(1033) : void WebKit::WebExtensionContext::loadBackgroundWebView()
        1   0x11e5f3459 WTFCrash
        2   0x13d2c8e7b WTFCrashWithInfo(int, char const*, char const*, int)
        3   0x13f97a5b0 WebKit::WebExtensionContext::loadBackgroundWebView()
        4   0x13f970b26 WebKit::WebExtensionContext::webViewWebContentProcessDidTerminate(WKWebView*)
        5   0x13f970a9e -[_WKWebExtensionContextDelegate webViewWebContentProcessDidTerminate:]
        6   0x13e7938e2 WebKit::NavigationState::NavigationClient::processDidTerminate(WebKit::WebPageProxy&, WebKit::ProcessTerminationReason)
        7   0x13edf8769 WebKit::WebPageProxy::dispatchProcessDidTerminate(WebKit::ProcessTerminationReason)
        8   0x13ee2912f WebKit::WebProcessProxy::processDidTerminateOrFailedToLaunch(WebKit::ProcessTerminationReason)
        9   0x13ee28ae5 WebKit::WebProcessProxy::didClose(IPC::Connection&)
        10  0x1400436a0 IPC::Connection::dispatchDidCloseAndInvalidate()::$_15::operator()() const
        11  0x1400435d9 WTF::Detail::CallableWrapper<IPC::Connection::dispatchDidCloseAndInvalidate()::$_15, void>::call()
        12  0x11e623552 WTF::Function<void ()>::operator()() const
        13  0x11e6c3ebe WTF::RunLoop::performWork()
        14  0x11e6c945e WTF::RunLoop::performWork(void*)
        15  0x1183f0ebd __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__
        16  0x1183f0dfc __CFRunLoopDoSource0
        17  0x1183f05f9 __CFRunLoopDoSources0
        18  0x1183eadb3 __CFRunLoopRun
        19  0x1183ea637 CFRunLoopRunSpecific
        20  0x11ab629fc -[NSRunLoop(NSRunLoop) runMode:beforeDate:]
        21  0x11ab62c75 -[NSRunLoop(NSRunLoop) runUntilDate:]
        22  0x10edddaee TestWebKitAPI::Util::runFor(WTF::Seconds)
        23  0x10ec57033 TestWebKitAPI::WKWebExtensionController_BackgroundPageLoading_Test::TestBody()
        24  0x10ee7919b void testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*)
        25  0x10ee4fcaa void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*)
        26  0x10ee4fbf3 testing::Test::Run()
        27  0x10ee50c31 testing::TestInfo::Run()
        28  0x10ee51cb4 testing::TestSuite::Run()
        29  0x10ee603ac testing::internal::UnitTestImpl::RunAllTests()
        30  0x10ee7d54b bool testing::internal::HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*)
        31  0x10ee5fd8a bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*)
        Child process terminated with signal 11: Segmentation fault

https://results.webkit.org/?suite=api-tests&suite=api-tests&test=TestWebKitAPI.WKWebExtensionController.BackgroundPageLoading&test=TestWebKitAPI.WKWebExtensionController.BackgroundPageWithModulesLoading