mxCalendar totally crashes on newest ModX

Hi,

I have the ModX 2.3.3.

The mxCalendar seemed kinda promissing. However, when trying to just configure some events, mxCalendar crashes and my browser has to be reloaded.

I only need "month-view" on which one sees a repeating day in one color, and other periods in another color. Not even necessary to make them clickable.

Any hep would be greatly appreciated !

Kind regards