Optimizer causing cc checkout field to be hidden

I have isolated this issue to Siteground Optimizer by deactivating al other plugins. When it is active the credit card fields on the checkout page are hidden. Also the product pages in WooCommerce are normally a 4×4 grid but with the Optimizer activated the product page grid is messed up and each row overflows. This is mostly happening on ‘incognito’ or ‘inprivate’ browsers. I use this type of browsers to fulfill phone in customers.

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