diff -urp webkitgtk-2.20.1.orig/Source/WebCore/accessibility/AccessibilityObject.cpp webkitgtk-2.20.1/Source/WebCore/accessibility/AccessibilityObject.cpp
--- webkitgtk-2.20.1.orig/Source/WebCore/accessibility/AccessibilityObject.cpp	2018-04-09 07:00:57.000000000 -0500
+++ webkitgtk-2.20.1/Source/WebCore/accessibility/AccessibilityObject.cpp	2018-04-10 21:07:52.446048647 -0500
@@ -1771,7 +1771,7 @@ void AccessibilityObject::updateBackingS
     // Updating the layout may delete this object.
     RefPtr<AccessibilityObject> protectedThis(this);
     if (auto* document = this->document()) {
-        if (!document->view()->layoutContext().isInRenderTreeLayout() && !document->inRenderTreeUpdate() && !document->inStyleRecalc())
+        if (!document->view()->layoutContext().isInRenderTreeLayout() && !document->inRenderTreeUpdate() && document->isSafeToUpdateStyleOrLayout())
             document->updateLayoutIgnorePendingStylesheets();
     }
     updateChildrenIfNecessary();
diff -urp webkitgtk-2.20.1.orig/Source/WebCore/dom/Document.cpp webkitgtk-2.20.1/Source/WebCore/dom/Document.cpp
--- webkitgtk-2.20.1.orig/Source/WebCore/dom/Document.cpp	2018-03-05 05:36:37.000000000 -0600
+++ webkitgtk-2.20.1/Source/WebCore/dom/Document.cpp	2018-04-10 21:07:52.454048680 -0500
@@ -1940,11 +1940,10 @@ bool Document::needsStyleRecalc() const
     return false;
 }
 
-static bool isSafeToUpdateStyleOrLayout(const Document& document)
+bool Document::isSafeToUpdateStyleOrLayout() const
 {
     bool isSafeToExecuteScript = ScriptDisallowedScope::InMainThread::isScriptAllowed();
-    auto* frameView = document.view();
-    bool isInFrameFlattening = frameView && frameView->isInChildFrameWithFrameFlattening();
+    bool isInFrameFlattening = view() && view()->isInChildFrameWithFrameFlattening();
     bool isAssertionDisabled = ScriptDisallowedScope::LayoutAssertionDisableScope::shouldDisable();
     return isSafeToExecuteScript || isInFrameFlattening || !isInWebProcess() || isAssertionDisabled;
 }
@@ -1967,7 +1966,7 @@ bool Document::updateStyleIfNeeded()
     }
 
     // The early exit above for !needsStyleRecalc() is needed when updateWidgetPositions() is called in runOrScheduleAsynchronousTasks().
-    RELEASE_ASSERT_WITH_SECURITY_IMPLICATION(isSafeToUpdateStyleOrLayout(*this));
+    RELEASE_ASSERT_WITH_SECURITY_IMPLICATION(isSafeToUpdateStyleOrLayout());
 
     resolveStyle();
     return true;
@@ -1983,7 +1982,7 @@ void Document::updateLayout()
         ASSERT_NOT_REACHED();
         return;
     }
-    RELEASE_ASSERT_WITH_SECURITY_IMPLICATION(isSafeToUpdateStyleOrLayout(*this));
+    RELEASE_ASSERT_WITH_SECURITY_IMPLICATION(isSafeToUpdateStyleOrLayout());
 
     RenderView::RepaintRegionAccumulator repaintRegionAccumulator(renderView());
 
diff -urp webkitgtk-2.20.1.orig/Source/WebCore/dom/Document.h webkitgtk-2.20.1/Source/WebCore/dom/Document.h
--- webkitgtk-2.20.1.orig/Source/WebCore/dom/Document.h	2018-03-05 04:11:41.000000000 -0600
+++ webkitgtk-2.20.1/Source/WebCore/dom/Document.h	2018-04-10 21:07:52.454048680 -0500
@@ -1253,6 +1253,7 @@ public:
 
     bool inStyleRecalc() const { return m_inStyleRecalc; }
     bool inRenderTreeUpdate() const { return m_inRenderTreeUpdate; }
+    WEBCORE_EXPORT bool isSafeToUpdateStyleOrLayout() const;
 
     void updateTextRenderer(Text&, unsigned offsetOfReplacedText, unsigned lengthOfReplacedText);