# Welcome to the Highcharts Gantt JS (gantt) Options Reference

These pages outline the chart configuration options, and the methods and properties of Highcharts objects.

Feel free to search this API through the search bar or the navigation tree in the sidebar.

# tooltip.headerShape

The name of a symbol to use for the border around the tooltip header. Applies only when tooltip.split is enabled.

Custom callbacks for symbol path generation can also be added to `Highcharts.SVGRenderer.prototype.symbols` the same way as for series.marker.symbol.