Top of the stack: 3 com.apple.WebCore: WebCore::Page::setNeedsRecalcStyleInAllFrames + 9 <== 3 com.apple.WebCore: -[ScrollbarPainterControllerDelegate scrollerImpPair:updateScrollerStyleForNewRecommendedScrollerStyle:] + 413 I haven't been able to reproduce the crash, but I have a speculative fix. <rdar://problem/9241920>
Created attachment 89700 [details] Speculative fix
Thanks Adele! Checked in with revision 83943.