ment.createElementNS("http://www.w3.org/2000/svg", "svg");
            svg.setAttribute('width', '100%');
            svg.setAttribute('height', '100%');
            content.appendChild(svg);

            const {root} = transformer.transform(item.markdown);
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            const mm = Markmap.create(svg, {
                autoFit: true,
                zoom: true
            }, root);

            window.markmapInstance = mm;
        }
    }
    function closeViewer(