Hi Maykato,
Thanks for your reply. I actually noticed that the culprit file is the below JS file which is called by checkout on WooCommerce.
/wp-includes/js/jquery/jquery.min.js?ver=3.5.1
If I block the load of this file on Google DevTools, everything works even with WPBakery 6.7 enabled. Also it appears that only when WPBakery is enabled this file also loads on the checkout by WooCommerce.
As this file is initiated from WooCommerce side, I doubt WPBakery support can help me a lot. I wonder if you have more insight into that.
Thank you
Thanks Hannah for the prompt response. It is very helpful!
Thanks Olga. These are very helpful!
An even more elegant solution would be to add those custom fields to the ajax add-to-cart.