kaelkim

Hi @jamesosborne

I agree what you are saying about Site Kit may not the cause, but disabling Site Kit plugin or disabling the enhanced conversion tracking feature in Site Kit fixes issue, so wanted to share.

The site has a lot of plugins and not sure which one is being used clearly, so it was a bit hard to debug for me. However, I found that the variant_id field was not updating when the issue happens, so I decided to update the value manually by hooking some js script on woocommerce_update_variation_values trigger.

FYI, ?v querysting was wordpress default caching feature for geolocating, but I did disable it now.

Thanks

Issue still exists, but happens when you add item again.

So, when you visit the product page with variants share via Google Form, select any option and click add to cart. Once the item is added, click add to cart button again, then you will see an error.

I kept the enhanced conversion tracking on for you to have a look.

Please update me once you’ve seen, then I will disable it again.

1/ when the page is loaded, console gets and error about use

<script defer type="text/javascript" id="wp-data-js-after">
    /* <![CDATA[ */
    (function() {
        var userId = 0;
        var storageKey = "WP_DATA_USER_" + userId;
        wp.data.use(wp.data.plugins.persistence, {
            storageKey: storageKey
        });
    }
    )();
    /* ]]> */
</script>

2/ even with the error, add to cart works and it seems reloading the page

3/ here you get additional js errors
One error from wp-util.min.js:2 Uncaught TypeError: Cannot read properties of undefined (reading 'memoize')
Another error from add-to-cart-variation.min.js:1 Uncaught TypeError: wp.template is not a function and this error occur when changing product variant option.

Originally had an issue around Marionette but that seems to be gone, but the above js errors still happen.

Like I said, after adding the item to the cart, the error occur, you refresh the page error still happen, but when you type the url again on the browser, error disappear (so it goes bactk step 1/ above before adding the item to the cart but item is already in the cart)

Hope these information helps for debugging and locating the error.