Treegraph loses root node at exporting to svg, png and etc.

[artzub]

Good day!
Found that we lose root node at exporting to SVG, png if data is updated by both series.setData or series.update.
We have a chart with dynamically adding data here

Expected behaviour

Expect to have a similar tree in the exported png.

Actual behaviour

Currently, the chart loses the root node at exporting to SVG or png and we have this result:

Live demo with steps to reproduce

https://jsfiddle.net/0d8akt72/9/

Product version

Highcharts: 11.1.0

Workaround

I did some research and found that the chart use series.userOptions.data in getSVG method.
And figured out that the collection series.userOptions.data is broken. Possible, it is related with this bug.
But I made a workaround that fixes exporting:

const getSVG = (H) => {
  H.wrap(H.Chart.prototype, 'getSVG', function (proceed, chartOptions) {
    this.series.forEach((series) => {
      if (series.type !== 'treegraph') {
        return;
      }

      series.userOptions.data = series.data.map((point) => ({
        ...point.options,
      }));
    });
    return proceed.call(this, chartOptions);
  });
};

You can uncomment a line with using the workaround in the above link or use this link

[karolkolodziej]

Hi @artzub!
Thank you for investigating this and for the workaround it seems very accurate!