test

            w->SetAttribute("direction", "vertical");

            knownCss.push_back("flex-direction");

        }

    } else {

        auto dispIt = cssProps.find("display");

        if (dispIt != cssProps.end() &&

            (dispIt->second == "flex" || dispIt->second == "inline-flex")) {

            // CSS defaults flex-direction to row when display:flex/inline-flex

            // is set without an explicit flex-direction. Without this, the

            // widget's own "direction" default (vertical/column -- see e.g.

            // Container::Render's `direction == "horizontal" ? "row" :

            // "column"` ternary) silently stacks children the source page

            // laid out side by side, and Container/Section/Article never

            // even switch on flex layout at all (their Render() only emits

            // `display: flex` when direction/align_items/vertical_align is

            // non-empty).

            w->SetAttribute("direction", "horizontal");

        }

    }

}