Hello Olga,
Thanks for getting back to me.
1) As I have explained, I am not able to duplicate this error. If it is product related, I can’t tell which one. It seems to occur randomly several times per day on our production site. You suggested earlier that it might be a cacheing issue. Can you suggest a cacheing exclusion I might want to have WP Engine add to the site?
2) We are definitely NOT experiencing behavior as shown in your demo regarding the slideout add to cart option. I have configured our staging site that way and am providing credentials in the private area so you can have a look.
3)The styling CSS works for Alert version of add to cart notification. But this is not the desired choice, for sure. We really like the popup version, just not the fatal errors that come with it.
Thanks again for all your support, we can count on 8theme to help us with problems we might experience.
Regards,
Ben