Method _modifyTimestampBy

packages/main/src/MonthPicker.ts:349–356

* Modifies timestamp by a given amount of months and, * if necessary, loads the prev/next page. * @param amount * @param preserveDate whether to preserve the day of the month (f.e. 15th of March + 1 month = 15th of April) * @private

(amount: number, preserveDate?: boolean)

	 * @private
	 */
	_modifyTimestampBy(amount: number, preserveDate?: boolean) {
		// Modify the current timestamp
		this._safelyModifyTimestampBy(amount, "month", preserveDate);
		this._updateSecondTimestamp();

		// Notify the calendar to update its timestamp
		this.fireDecoratorEvent("navigate", { timestamp: this.timestamp! });
	}

	_onkeyup(e: KeyboardEvent) {
		if (isSpace(e)) {