Conditional Image in FlexboxLayout causes overflow

export component Demo inherits Window {
    width: 100px; height: 100px;
    background: red;
    FlexboxLayout {
        if true: Rectangle {
            width: 40px;
            FlexboxLayout {
                flex-direction: column;
                padding: 8px;
                Image {
                    height: 24px;
                    preferred-width: 24px;
                    source: @image-url("data:image/png;base64,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");
                }
            }
        }
    }
}