Crash report: https://crash-stats.mozilla.org/report/index/195dd750-3855-4611-9966-bb3b80220618

Reason: EXCEPTION_ACCESS_VIOLATION_READ

Top 10 frames of crashing thread:

0 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7438
1 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7441
2 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7441
3 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7441
4 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7441
5 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7441
6 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7441
7 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7441
8 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7441
9 xul.dll nsIFrame::ClearInvalidationStateBits layout/generic/nsIFrame.cpp:7441
...
 60 	xul.dll	nsIFrame::ClearInvalidationStateBits()	layout/generic/nsIFrame.cpp:7441
61 	xul.dll	mozilla::nsDisplayList::PaintRoot(mozilla::nsDisplayListBuilder*, gfxContext*, unsigned int, mozilla::Maybe<double>)	layout/painting/nsDisplayList.cpp:2328
62 	xul.dll	static nsLayoutUtils::PaintFrame(gfxContext*, nsIFrame*, nsRegion const&, unsigned int, mozilla::nsDisplayListBuilderMode, nsLayoutUtils::PaintFrameFlags)	layout/base/nsLayoutUtils.cpp:3450
63 	xul.dll	mozilla::PresShell::PaintInternal(nsView*, mozilla::PaintInternalFlags)	layout/base/PresShell.cpp:6436
64 	xul.dll	mozilla::PresShell::PaintAndRequestComposite(nsView*, mozilla::PaintFlags)	layout/base/PresShell.cpp:6311
65 	xul.dll	nsViewManager::ProcessPendingUpdatesPaint(nsIWidget*)	view/nsViewManager.cpp:440
66 	xul.dll	nsViewManager::ProcessPendingUpdatesForView(nsView*, bool)	view/nsViewManager.cpp:375
67 	xul.dll	nsViewManager::ProcessPendingUpdates()	view/nsViewManager.cpp:948
68 	xul.dll	nsRefreshDriver::Tick(mozilla::layers::BaseTransactionId<mozilla::VsyncIdType>, mozilla::TimeStamp, nsRefreshDriver::IsExtraTick)	layout/base/nsRefreshDriver.cpp:2700
69 	xul.dll	mozilla::RefreshDriverTimer::TickRefreshDrivers(mozilla::layers::BaseTransactionId<mozilla::VsyncIdType>, mozilla::TimeStamp, nsTArray<RefPtr<nsRefreshDriver> >&)	layout/base/nsRefreshDriver.cpp:346 

Firefox bp-f184946a-33a4-42cd-a424-c0d1f0220615

https://hg.mozilla.org/releases/mozilla-esr102/file/tip/layout/generic/nsIFrame.cpp#l7441 - child->ClearInvalidationStateBits() - is child null?