Reduced with m-c:
BuildID=20190911160523
SourceStamp=ba563f823a564dfade0327d003143d765ac9ab59

Assertion failure: summaryAccessible (Details objects should have at least one summary), at src/accessible/html/HTMLElementAccessibles.cpp:174

#0 mozilla::a11y::HTMLSummaryAccessible::FromDetails(mozilla::a11y::Accessible*) src/accessible/html/HTMLElementAccessibles.cpp:160:37
#1 mozilla::a11y::DocAccessible::AttributeChangedImpl(mozilla::a11y::Accessible*, int, nsAtom*) src/accessible/generic/DocAccessible.cpp:795:13
#2 mozilla::a11y::DocAccessible::AttributeChanged(mozilla::dom::Element*, int, nsAtom*, int, nsAttrValue const*) src/accessible/generic/DocAccessible.cpp:731:3
#3 nsNodeUtils::AttributeChanged(mozilla::dom::Element*, int, nsAtom*, int, nsAttrValue const*) src/dom/base/nsNodeUtils.cpp:159:3
#4 mozilla::dom::Element::UnsetAttr(int, nsAtom*, bool) src/dom/base/Element.cpp:2824:5
#5 mozilla::dom::Element::UnsetAttr(nsAtom*, mozilla::ErrorResult&) src/obj-firefox/dist/include/mozilla/dom/Element.h:1551:14
#6 mozilla::dom::HTMLDetailsElement_Binding::set_open(JSContext*, JS::Handle<JSObject*>, mozilla::dom::HTMLDetailsElement*, JSJitSetterCallArgs) src/obj-firefox/dom/bindings/HTMLDetailsElementBinding.cpp:63:24
#7 bool mozilla::dom::binding_detail::GenericSetter<mozilla::dom::binding_detail::NormalThisPolicy>(JSContext*, unsigned int, JS::Value*) src/dom/bindings/BindingUtils.cpp:3121:8
#8 CallJSNative(JSContext*, bool (*)(JSContext*, unsigned int, JS::Value*), JS::CallArgs const&) src/js/src/vm/Interpreter.cpp:447:13
#9 js::InternalCallOrConstruct(JSContext*, JS::CallArgs const&, js::MaybeConstruct) src/js/src/vm/Interpreter.cpp:539:12
#10 InternalCall(JSContext*, js::AnyInvokeArgs const&) src/js/src/vm/Interpreter.cpp:594:10
#11 js::Call(JSContext*, JS::Handle<JS::Value>, JS::Handle<JS::Value>, js::AnyInvokeArgs const&, JS::MutableHandle<JS::Value>) src/js/src/vm/Interpreter.cpp:610:8
#12 js::CallSetter(JSContext*, JS::Handle<JS::Value>, JS::Handle<JS::Value>, JS::Handle<JS::Value>) src/js/src/vm/Interpreter.cpp:748:10
#13 SetExistingProperty(JSContext*, JS::Handle<JS::PropertyKey>, JS::Handle<JS::Value>, JS::Handle<JS::Value>, JS::Handle<js::NativeObject*>, JS::Handle<JS::PropertyResult>, JS::ObjectOpResult&) src/js/src/vm/NativeObject.cpp:2932:8
#14 bool js::NativeSetProperty<(js::QualifiedBool)1>(JSContext*, JS::Handle<js::NativeObject*>, JS::Handle<JS::PropertyKey>, JS::Handle<JS::Value>, JS::Handle<JS::Value>, JS::ObjectOpResult&) src/js/src/vm/NativeObject.cpp:2961:14
#15 js::SetProperty(JSContext*, JS::Handle<JSObject*>, JS::Handle<JS::PropertyKey>, JS::Handle<JS::Value>, JS::Handle<JS::Value>, JS::ObjectOpResult&) src/js/src/vm/ObjectOperations-inl.h:283:10
#16 SetPropertyOperation(JSContext*, JSOp, JS::Handle<JS::Value>, JS::Handle<JS::PropertyKey>, JS::Handle<JS::Value>) src/js/src/vm/Interpreter.cpp:269:10
#17 Interpret(JSContext*, js::RunState&) src/js/src/vm/Interpreter.cpp:2849:12
#18 js::RunScript(JSContext*, js::RunState&) src/js/src/vm/Interpreter.cpp:424:10
#19 js::InternalCallOrConstruct(JSContext*, JS::CallArgs const&, js::MaybeConstruct) src/js/src/vm/Interpreter.cpp:567:13
#20 InternalCall(JSContext*, js::AnyInvokeArgs const&) src/js/src/vm/Interpreter.cpp:594:10
#21 js::Call(JSContext*, JS::Handle<JS::Value>, JS::Handle<JS::Value>, js::AnyInvokeArgs const&, JS::MutableHandle<JS::Value>) src/js/src/vm/Interpreter.cpp:610:8
#22 JS::Call(JSContext*, JS::Handle<JS::Value>, JS::Handle<JS::Value>, JS::HandleValueArray const&, JS::MutableHandle<JS::Value>) src/js/src/jsapi.cpp:2723:10
#23 mozilla::dom::EventHandlerNonNull::Call(JSContext*, JS::Handle<JS::Value>, mozilla::dom::Event&, JS::MutableHandle<JS::Value>, mozilla::ErrorResult&) src/obj-firefox/dom/bindings/EventHandlerBinding.cpp:267:37
#24 void mozilla::dom::EventHandlerNonNull::Call<nsCOMPtr<mozilla::dom::EventTarget> >(nsCOMPtr<mozilla::dom::EventTarget> const&, mozilla::dom::Event&, JS::MutableHandle<JS::Value>, mozilla::ErrorResult&, char const*, mozilla::dom::CallbackObject::ExceptionHandling, JS::Realm*) src/obj-firefox/dist/include/mozilla/dom/EventHandlerBinding.h:363:12
#25 mozilla::JSEventHandler::HandleEvent(mozilla::dom::Event*) src/dom/events/JSEventHandler.cpp:205:12
#26 mozilla::EventListenerManager::HandleEventSubType(mozilla::EventListenerManager::Listener*, mozilla::dom::Event*, mozilla::dom::EventTarget*) src/dom/events/EventListenerManager.cpp:1038:22
#27 mozilla::EventListenerManager::HandleEventInternal(nsPresContext*, mozilla::WidgetEvent*, mozilla::dom::Event**, mozilla::dom::EventTarget*, nsEventStatus*, bool) src/dom/events/EventListenerManager.cpp:1230:17
#28 mozilla::EventTargetChainItem::HandleEvent(mozilla::EventChainPostVisitor&, mozilla::ELMCreationDetector&) src/dom/events/EventDispatcher.cpp:349:17
#29 mozilla::EventTargetChainItem::HandleEventTargetChain(nsTArray<mozilla::EventTargetChainItem>&, mozilla::EventChainPostVisitor&, mozilla::EventDispatchingCallback*, mozilla::ELMCreationDetector&) src/dom/events/EventDispatcher.cpp:551:16
#30 mozilla::EventDispatcher::Dispatch(nsISupports*, nsPresContext*, mozilla::WidgetEvent*, mozilla::dom::Event*, nsEventStatus*, mozilla::EventDispatchingCallback*, nsTArray<mozilla::dom::EventTarget*>*) src/dom/events/EventDispatcher.cpp:1045:11
#31 nsDocumentViewer::LoadComplete(nsresult) src/layout/base/nsDocumentViewer.cpp:1170:7
#32 nsDocShell::EndPageLoad(nsIWebProgress*, nsIChannel*, nsresult) src/docshell/base/nsDocShell.cpp:6542:20
#33 nsDocShell::OnStateChange(nsIWebProgress*, nsIRequest*, unsigned int, nsresult) src/docshell/base/nsDocShell.cpp:6320:7
#34 non-virtual thunk to nsDocShell::OnStateChange(nsIWebProgress*, nsIRequest*, unsigned int, nsresult) src/docshell/base/nsDocShell.cpp
#35 nsDocLoader::DoFireOnStateChange(nsIWebProgress*, nsIRequest*, int&, nsresult) src/uriloader/base/nsDocLoader.cpp:1333:3
#36 nsDocLoader::doStopDocumentLoad(nsIRequest*, nsresult) src/uriloader/base/nsDocLoader.cpp:892:14
#37 nsDocLoader::DocLoaderIsEmpty(bool) src/uriloader/base/nsDocLoader.cpp:726:9
#38 nsDocLoader::OnStopRequest(nsIRequest*, nsresult) src/uriloader/base/nsDocLoader.cpp:614:5
#39 non-virtual thunk to nsDocLoader::OnStopRequest(nsIRequest*, nsresult) src/uriloader/base/nsDocLoader.cpp
#40 mozilla::net::nsLoadGroup::RemoveRequest(nsIRequest*, nsISupports*, nsresult) src/netwerk/base/nsLoadGroup.cpp:568:22
#41 imgRequestProxy::RemoveFromLoadGroup() src/image/imgRequestProxy.cpp:404:15
#42 imgRequestProxy::OnLoadComplete(bool) src/image/imgRequestProxy.cpp:1048:7
#43 void mozilla::image::ImageObserverNotifier<mozilla::image::ObserverTable const*>::operator()<void mozilla::image::SyncNotifyInternal<mozilla::image::ObserverTable const*>(mozilla::image::ObserverTable const* const&, bool, unsigned int, mozilla::gfx::IntRectTyped<mozilla::gfx::UnknownUnits> const&)::'lambda5'(mozilla::image::IProgressObserver*)>(mozilla::image::ObserverTable const*) src/image/ProgressTracker.cpp:283:9
#44 void mozilla::image::SyncNotifyInternal<mozilla::image::ObserverTable const*>(mozilla::image::ObserverTable const* const&, bool, unsigned int, mozilla::gfx::IntRectTyped<mozilla::gfx::UnknownUnits> const&) src/image/ProgressTracker.cpp:352:5
#45 mozilla::image::ProgressTracker::SyncNotifyProgress(unsigned int, mozilla::gfx::IntRectTyped<mozilla::gfx::UnknownUnits> const&)::$_1::operator()(mozilla::image::ObserverTable const*) const src/image/ProgressTracker.cpp:371:5
#46 decltype(fp(static_cast<mozilla::image::ObserverTable const*>(std::nullptr_t))) mozilla::image::CopyOnWrite<mozilla::image::ObserverTable>::Read<mozilla::image::ProgressTracker::SyncNotifyProgress(unsigned int, mozilla::gfx::IntRectTyped<mozilla::gfx::UnknownUnits> const&)::$_1>(mozilla::image::ProgressTracker::SyncNotifyProgress(unsigned int, mozilla::gfx::IntRectTyped<mozilla::gfx::UnknownUnits> const&)::$_1) const src/image/CopyOnWrite.h:155:12
#47 mozilla::image::ProgressTracker::SyncNotifyProgress(unsigned int, mozilla::gfx::IntRectTyped<mozilla::gfx::UnknownUnits> const&) src/image/ProgressTracker.cpp:370:14
#48 imgRequest::OnStopRequest(nsIRequest*, nsresult) src/image/imgRequest.cpp:811:22
#49 nsBaseChannel::OnStopRequest(nsIRequest*, nsresult) src/netwerk/base/nsBaseChannel.cpp:846:16
#50 non-virtual thunk to nsBaseChannel::OnStopRequest(nsIRequest*, nsresult) src/netwerk/base/nsBaseChannel.cpp
#51 nsInputStreamPump::OnStateStop() src/netwerk/base/nsInputStreamPump.cpp:655:16
#52 nsInputStreamPump::OnInputStreamReady(nsIAsyncInputStream*) src/netwerk/base/nsInputStreamPump.cpp:403:21
#53 non-virtual thunk to nsInputStreamPump::OnInputStreamReady(nsIAsyncInputStream*) src/netwerk/base/nsInputStreamPump.cpp
#54 nsInputStreamReadyEvent::Run() src/xpcom/io/nsStreamUtils.cpp:91:20
#55 mozilla::SchedulerGroup::Runnable::Run() src/xpcom/threads/SchedulerGroup.cpp:295:32
#56 nsThread::ProcessNextEvent(bool, bool*) src/xpcom/threads/nsThread.cpp:1225:14
#57 NS_ProcessNextEvent(nsIThread*, bool) src/xpcom/threads/nsThreadUtils.cpp:486:10
#58 mozilla::ipc::MessagePump::Run(base::MessagePump::Delegate*) src/ipc/glue/MessagePump.cpp:88:21
#59 MessageLoop::RunInternal() src/ipc/chromium/src/base/message_loop.cc:315:10
#60 MessageLoop::Run() src/ipc/chromium/src/base/message_loop.cc:290:3
#61 nsBaseAppShell::Run() src/widget/nsBaseAppShell.cpp:137:27
#62 XRE_RunAppShell() src/toolkit/xre/nsEmbedFunctions.cpp:934:20
#63 mozilla::ipc::MessagePumpForChildProcess::Run(base::MessagePump::Delegate*) src/ipc/glue/MessagePump.cpp:238:9
#64 MessageLoop::RunInternal() src/ipc/chromium/src/base/message_loop.cc:315:10
#65 MessageLoop::Run() src/ipc/chromium/src/base/message_loop.cc:290:3
#66 XRE_InitChildProcess(int, char**, XREChildData const*) src/toolkit/xre/nsEmbedFunctions.cpp:769:34
#67 content_process_main(mozilla::Bootstrap*, int, char**) src/browser/app/../../ipc/contentproc/plugin-container.cpp:56:28
#68 main src/browser/app/nsBrowserApp.cpp:272:18

Ug. So a details Accessible might not have a summary Accessible if the summary is aria-hidden or CSS display: none, since both of these explicitly remove something from the a11y tree. I guess we should just kill the assertion?

(In reply to James Teh [:Jamie] from comment #1)

Ug. So a details Accessible might not have a summary Accessible if the summary is aria-hidden or CSS display: none, since both of these explicitly remove something from the a11y tree. I guess we should just kill the assertion?

Ah. Yeah I didn't consider that. I'll take this and update tomorrow.

https://hg.mozilla.org/mozilla-central/rev/761a797147a7