P.S Error screen contents
=> Internal server error. Error: Gantt to Excel. TypeError: excelRefs variable sent to mergeCells function must be an array with length > 0
Gantt allows adding tasks with these dates, but when you export the data to Excel with the visual: true parameter, the export server doesn’t expect that.
If you fix the duration and end_date parameters, the data will be exported correctly:
Could you share how you expect it to work with the negative duration when you try to export to Excel? Should the Gantt correct it to 0, remove the negative value, or throw an error?
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