Hello and welcome to our forum!
Thanks for contacting us with your question. Unfortunately, Highcharts Gantt doesn't have a property that allows to set individual row height, because row placement is calculated by chart height. You can try using
yAxis.staticScale property, although it applies to all rows on Axis.
There is a similar topic on GitHub Highcharts repository, which has a workaround:
https://github.com/highcharts/highchart ... -791540339. If you want, you can upvote this feature request, so it might get implemented in the future.
References:
https://api.highcharts.com/gantt/yAxis.staticScale
https://api.highcharts.com/gantt/yAxis.breaks
In case of any other questions related to Highcharts functionality feel free to contact us anytime.
Best regards!