The test case will require a fuzzing build (--enable-fuzzing) since it makes use of window.printPreview()

Assertion failure: !child->IsRelocated() (Child should be in its ordinal position), at src/accessible/generic/DocAccessible.cpp:2290

#0 0x7f9f677d84a8 in mozilla::a11y::DocAccessible::DoARIAOwnsRelocation(mozilla::a11y::Accessible*) src/accessible/generic/DocAccessible.cpp:2289:9
#1 0x7f9f6779add6 in mozilla::a11y::NotificationController::WillRefresh(mozilla::TimeStamp) src/accessible/base/NotificationController.cpp:822:18
#2 0x7f9f66689c9e in nsRefreshDriver::Tick(mozilla::layers::BaseTransactionId<mozilla::VsyncIdType>, mozilla::TimeStamp) src/layout/base/nsRefreshDriver.cpp:2138:12
#3 0x7f9f66691f21 in TickDriver src/layout/base/nsRefreshDriver.cpp:357:13
#4 0x7f9f66691f21 in mozilla::RefreshDriverTimer::TickRefreshDrivers(mozilla::layers::BaseTransactionId<mozilla::VsyncIdType>, mozilla::TimeStamp, nsTArray<RefPtr<nsRefreshDriver> >&) src/layout/base/nsRefreshDriver.cpp:336:7
#5 0x7f9f66691e0c in mozilla::RefreshDriverTimer::Tick(mozilla::layers::BaseTransactionId<mozilla::VsyncIdType>, mozilla::TimeStamp) src/layout/base/nsRefreshDriver.cpp:351:5
#6 0x7f9f666913b8 in RunRefreshDrivers src/layout/base/nsRefreshDriver.cpp:799:5
#7 0x7f9f666913b8 in mozilla::VsyncRefreshDriverTimer::RefreshDriverVsyncObserver::TickRefreshDriver(mozilla::layers::BaseTransactionId<mozilla::VsyncIdType>, mozilla::TimeStamp) src/layout/base/nsRefreshDriver.cpp:722:16
#8 0x7f9f66690cd0 in mozilla::VsyncRefreshDriverTimer::RefreshDriverVsyncObserver::NotifyParentProcessVsync() src/layout/base/nsRefreshDriver.cpp:624:7
#9 0x7f9f66690749 in mozilla::VsyncRefreshDriverTimer::RefreshDriverVsyncObserver::NotifyVsync(mozilla::VsyncEvent const&) src/layout/base/nsRefreshDriver.cpp:545:9
#10 0x7f9f65e9ca86 in mozilla::dom::VsyncChild::RecvNotify(mozilla::VsyncEvent const&, float const&) src/dom/ipc/VsyncChild.cpp:69:15
#11 0x7f9f62c90db0 in mozilla::dom::PVsyncChild::OnMessageReceived(IPC::Message const&) /builds/worker/workspace/obj-build/ipc/ipdl/PVsyncChild.cpp:178:54
#12 0x7f9f62a3b96c in mozilla::ipc::PBackgroundChild::OnMessageReceived(IPC::Message const&) /builds/worker/workspace/obj-build/ipc/ipdl/PBackgroundChild.cpp:6286:32
#13 0x7f9f626f9b1e in mozilla::ipc::MessageChannel::DispatchAsyncMessage(mozilla::ipc::ActorLifecycleProxy*, IPC::Message const&) src/ipc/glue/MessageChannel.cpp:2153:25
#14 0x7f9f626f611d in mozilla::ipc::MessageChannel::DispatchMessage(IPC::Message&&) src/ipc/glue/MessageChannel.cpp:2077:9
#15 0x7f9f626f75c6 in mozilla::ipc::MessageChannel::RunMessage(mozilla::ipc::MessageChannel::MessageTask&) src/ipc/glue/MessageChannel.cpp:1925:3
#16 0x7f9f626f830b in mozilla::ipc::MessageChannel::MessageTask::Run() src/ipc/glue/MessageChannel.cpp:1956:13
#17 0x7f9f61ddce1f in mozilla::RunnableTask::Run() src/xpcom/threads/TaskController.cpp:459:16
#18 0x7f9f61ddb41a in mozilla::TaskController::DoExecuteNextTaskOnlyMainThreadInternal(mozilla::detail::BaseAutoLock<mozilla::Mutex&> const&) src/xpcom/threads/TaskController.cpp:739:26
#19 0x7f9f61dda4c4 in mozilla::TaskController::ExecuteNextTaskOnlyMainThreadInternal(mozilla::detail::BaseAutoLock<mozilla::Mutex&> const&) src/xpcom/threads/TaskController.cpp:598:15
#20 0x7f9f61dda677 in mozilla::TaskController::ProcessPendingMTTask(bool) src/xpcom/threads/TaskController.cpp:382:36
#21 0x7f9f61de0739 in operator() src/xpcom/threads/TaskController.cpp:126:37
#22 0x7f9f61de0739 in mozilla::detail::RunnableFunction<mozilla::TaskController::InitializeInternal()::$_4>::Run() /builds/worker/workspace/obj-build/dist/include/nsThreadUtils.h:534:5
#23 0x7f9f61df1cb5 in nsThread::ProcessNextEvent(bool, bool*) src/xpcom/threads/nsThread.cpp:1200:14
#24 0x7f9f61df7d6a in NS_ProcessNextEvent(nsIThread*, bool) src/xpcom/threads/nsThreadUtils.cpp:548:10
#25 0x7f9f626ff3a4 in mozilla::ipc::MessagePump::Run(base::MessagePump::Delegate*) src/ipc/glue/MessagePump.cpp:109:5
#26 0x7f9f6266b5b3 in MessageLoop::RunInternal() src/ipc/chromium/src/base/message_loop.cc:334:10
#27 0x7f9f6266b4cd in RunHandler src/ipc/chromium/src/base/message_loop.cc:327:3
#28 0x7f9f6266b4cd in MessageLoop::Run() src/ipc/chromium/src/base/message_loop.cc:309:3
#29 0x7f9f663e4d08 in nsBaseAppShell::Run() src/widget/nsBaseAppShell.cpp:137:27
#30 0x7f9f67beda93 in XRE_RunAppShell() src/toolkit/xre/nsEmbedFunctions.cpp:902:20
#31 0x7f9f627002d9 in mozilla::ipc::MessagePumpForChildProcess::Run(base::MessagePump::Delegate*) src/ipc/glue/MessagePump.cpp:237:9
#32 0x7f9f6266b5b3 in MessageLoop::RunInternal() src/ipc/chromium/src/base/message_loop.cc:334:10
#33 0x7f9f6266b4cd in RunHandler src/ipc/chromium/src/base/message_loop.cc:327:3
#34 0x7f9f6266b4cd in MessageLoop::Run() src/ipc/chromium/src/base/message_loop.cc:309:3
#35 0x7f9f67bed678 in XRE_InitChildProcess(int, char**, XREChildData const*) src/toolkit/xre/nsEmbedFunctions.cpp:733:34
#36 0x5563b44efe07 in content_process_main src/browser/app/../../ipc/contentproc/plugin-container.cpp:57:28
#37 0x5563b44efe07 in main src/browser/app/nsBrowserApp.cpp:305:18

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