test

                        std::string viewBox, inner;

                        svgmarkup::parse(customIconSvg, viewBox, inner);

                        std::string vb = viewBox.empty() ? "0 0 24 24" : viewBox;

                        // fill="currentColor" so an icon whose paths don't hardcode

                        // their own color inherits the card's text color instead of

                        // rendering in whatever color happened to be authored (often

                        // black, which can look "wrong" or vanish on a dark card).

                        // Explicit Icon Color wins; otherwise fall back to

                        // currentColor so an icon whose paths don't hardcode

                        // their own color at least inherits the ambient text

                        // color instead of whatever it happened to be authored in.

                        std::string iconFill = validCss(iconColor) ? iconColor : "currentColor";

                        std::string iconSvgHtml = "<svg width=\"28\" height=\"28\" viewBox=\"" + vb +

                                                   "\" fill=\"currentColor\" xmlns=\"http://www.w3.org/2000/svg\">" + inner + "</svg>";

                                                   "\" fill=\"" + iconFill + "\" xmlns=\"http://www.w3.org/2000/svg\">" + inner + "</svg>";

                        try {

                            libhtmlpp::HtmlString htmlBuf(iconSvgHtml);

                            libhtmlpp::Element &parsed = htmlBuf.parse();