SVGListPropertyTearOff is keeping a ref to AnimatedListPropertyTearOff (RefPtr<AnimatedListPropertyTearOff> m_animatedProperty) AnimatedListPropertyTearOff is also keeping a ref to SVGListPropertyTearOff (RefPtr<SVGProperty> m_baseVal, RefPtr<SVGProperty> m_animVal) These 2 objects are referencing each other and are never released.
SVG property tear-off object were removed in bug 191237. *** This bug has been marked as a duplicate of bug 191237 ***