Fullcalendar: save external events immediately in SQL db - fullcalendar

Question

I searched Stackoverflow for an answer to my question: How to save dropped external events immediately to the database. Adding and updating events through the dialog works fine. Dragged external events are rendered fine.
This is the code I use in the eventReceive function. The first alert to show the event data is correct, but the second is never reached.
eventReceive: function (event, delta, revertFunc) {
alert(event.title + " was dropped on " + event.start.format()); //REPLACE WITH AJAX TO SAVE EVENT DATA
var eventToAdd = {
title: event.title,
description: "Unknown",
start: event.start.format,
end: event.end.format,
allDay: isAllDay(event.StartDate, event.EndDate)
};
if (checkForSpecialChars(eventToAdd.title) || checkForSpecialChars(eventToAdd.description)) {
alert("please enter characters: A to Z, a to z, 0 to 9, spaces");
}
else {
alert(event.title + " was dropped on " + event.start.format());
PageMethods.addEvent(eventToAdd, addSuccess);
}
},
I digged somewhat deeper and as far as I can tell, after the var eventToAdd JQuery 3.3.1 triggers the same functions over and over again as soon as the mouse is hovered over any element in the page. Functions involved are: matchFromGroupMatchers, elementmatcher, prefilter and Sizzle. The javascript of fullcalendar does not resume.

Answer 1

It seems the variable eventToAdd was in use. Changing it to a different name solved it. I have it now this way:
eventReceive: function (event) {
// alert(event.title + " was dropped on " + event.start.format());
var eventAdd = {
start: event.start.format(),
end: event.end.format(),
title: event.title,
description: "Onbekend",
hwType: "Proefwerk",
};
PageMethods.addEvent(eventAdd, addSuccess);
},