Webform Data Popup calendar causes JS error when adding to a Panel

The JS console led me to the calender field in Webforms. When enabled the buttons did not work. Once I removed the calender fields the buttons came back on.

I have not moved a issue before. Do I just change the Issue settings?

I am moving this from Panels for review. I managed to isolate the problem but due not know how solve the issue for others.

Here is what I got when recreated. I issue is present when in the edit panel UI.

Error: $calendar[0] is undefined
Source File: http://XXXXX/sites/all/modules/webform/js/webform.js?ll3m9y
Line: 21

/**
* JavaScript behaviors for the front-end display of webforms.
*/

(function ($) {

Drupal.behaviors.webform = Drupal.behaviors.webform || {};

Drupal.behaviors.webform.attach = function(context) {
// Calendar datepicker behavior.
Drupal.webform.datepicker(context);
};

Drupal.webform = Drupal.webform || {};

Drupal.webform.datepicker = function(context) {
$('div.webform-datepicker').each(function() {
var $webformDatepicker = $(this);
var $calendar = $webformDatepicker.find('input.webform-calendar');
var startYear = $calendar[0].className.replace(/.*webform-calendar-start-(\d+).*/, '$1');
var endYear = $calendar[0].className.replace(/.*webform-calendar-end-(\d+).*/, '$1');
var firstDay = $calendar[0].className.replace(/.*webform-calendar-day-(\d).*/, '$1');

// Ensure that start comes before end for datepicker.
if (startYear > endYear) {
var greaterYear = startYear;
startYear = endYear;
endYear = greaterYear;
}

// Set up the jQuery datepicker element.
$calendar.datepicker({
dateFormat: 'yy-mm-dd',
yearRange: startYear + ':' + endYear,
firstDay: parseInt(firstDay),
onSelect: function(dateText, inst) {
var date = dateText.split('-');
$webformDatepicker.find('select.year, input.year').val(+date[0]);
$webformDatepicker.find('select.month').val(+date[1]);
$webformDatepicker.find('select.day').val(+date[2]);
},
beforeShow: function(input, inst) {
// Get the select list values.
var year = $webformDatepicker.find('select.year, input.year').val();
var month = $webformDatepicker.find('select.month').val();
var day = $webformDatepicker.find('select.day').val();

// If empty, default to the current year/month/day in the popup.
var today = new Date();
year = year ? year : today.getFullYear();
month = month ? month : today.getMonth() + 1;
day = day ? day : today.getDate();

// Make sure that the default year fits in the available options.
year = (year < startYear || year > endYear) ? startYear : year;

// jQuery UI Datepicker will read the input field and base its date off
// of that, even though in our case the input field is a button.
$(input).val(year + '-' + month + '-' + day);
}
});

// Prevent the calendar button from submitting the form.
$calendar.click(function(event) {
$(this).focus();
event.preventDefault();
});
});
}

})(jQuery);

I added the code and the add content button is there. I added content. The fix look good.

Thanks