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

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

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# exporting.error

Function to call if the offline-exporting module fails to export a chart on the client side, and fallbackToExportServer is disabled. If left undefined, an exception is thrown instead. Receives two parameters, the exporting options, and the error from the module.

Since v13, PDF client-side export dependencies are opt-in. If `jsPDF` and `svg2pdf` are not present on `window` and `exporting.libURL` is not defined, a console warning is emitted on chart load. When fallback is disabled and no `exporting.error` handler is defined, the thrown error will use the underlying error message when available (for example, missing `jsPDF`/`svg2pdf`) instead of always throwing error `#28`.