timezone local

Hi,
I have already asked something similar on events manager but maybe it is more suitable here.
The article here https://fullcalendar.io/docs/timeZone seems to suggest that full calendar should default to the visitor’s time zone.
However on my site using events manager and wp full calendar with timezone support set to YES the events appears at the same time regardless of event time zones or the visiting computer timezone. I found something in the jquery on the page the function that loads full calendar has this in it
ignoreTimezone: true,
So I suspect that might be the issue? Can you suggest a way to overwrite it and display the event’s in the visitor’s timezone instead? I am not sure why none of the calendar solutions support this as it seems the most logical and needed feature in the modern world.