Good evening Kristopher and welcome to the Events Calendar Support forum!
Thank you for reaching out to us.
We are sorry to hear about the JS error creeping up on your site.
I would love to help you with this topic.
My first recommendation would be to update the Events Calendar Pro plugin to it’s latest version (4.3.1.1) as matching versions are always recommended when possible.
Secondly, if that does not solve the issue.
The next step would be to go through our testing for conflicts procedure (preferably in a staging/dev environment or local install of your WordPress website) and let us know what you find out.
Basically the goal here is to revert back to a bare WordPress installation to see if the problem persists. It also allows us to pinpoint what the cause of the issue is.
But, before you do that, there are 2 things I would advise:
- Make a backup of your database
- Consider activating a “Maintenance Page” plugin if you are doing this on your live site (to minimize impact on your visitors)
Let me know how that goes.
Best regards,
Geoff B.