Wrong position of long data labels when dataLabels.useHTML = true in treemap series

[jszuminski]

Expected behaviour

Long data labels with series.dataLabels.useHTML: true in treemap should be middle-aligned just like shorter data labels.

Actual behaviour

Long data labels with series.dataLabels.useHTML: true in treemap are initially positioned in the wrong position (shifted up a little bit).

Live demo

Demo: https://jsfiddle.net/BlackLabel/gztqdyca/

Product version

Highcharts 10.3.2

Workaround

Fire chart.reflow() in the chart.events.load callback function.
Demo: https://jsfiddle.net/BlackLabel/ghsmLxpf/