fred@igalia-fwang:~/webkit/WebKit$ grep m_ Source/WebCore/rendering/mathml/RenderMathMLRoot.h MathOperator m_radicalOperator; LayoutUnit m_radicalOperatorTop; LayoutUnit m_baseWidth; This is similar to bug 180151. We can probably refactor the code so that we don't need m_radicalOperatorTop and m_baseWidth and that should be easier after bug 180348.