private String translateViewNames(String viewNamesOld) {
        if (viewNamesOld != null) {
            return Stream.of(viewNamesOld.split(","))
                    .map(v -> translateViewName(v.trim()))
                    .collect(Collectors.joining(","));
        }

        return null;
    }
Translates old FullCalendar-ViewName (<=V3) to new FullCalendar-ViewName (>=V4)
@param viewNameOld
@return
primefaces/src/main/java/org/primefaces/component/schedule/ScheduleRenderer.java