The onBeforeHeaderExport event is fired by the monthly calendar during image export and direct printing. It allows you to provide alternative text (instead of HTML) and customize the formatting.
Available since 2019.1.3554.
DayPilot.Month.onBeforeHeaderExport(args);args.header.dayOfWeek (number; 0-6; 0 = Sunday)
args.backColor
args.fontSize
args.fontFamily
args.fontStyle
args.fontColor
args.horizontalAlignment ("left" | "center" | "right")
args.text