Re: Used Style Computation (and Viewport/Canvas Layout)

> Well, the point is that given the spec for overflow:auto, if you have an 
> element that you don't want to leak layout stuff to ancestors you have to 
> make sure its overflow is not "visible".

What do you mean by "visible" here? Do you mean "visible" as in "not drawn" 
or as in "should not have any side effet" ?