Klarna Payments – Optimizing your WooCommerce cart/checkout when using an Iframe-based checkout

Optimizing can be very powerful when it’s properly configured but when using a Iframe-base checkout such as Klarna Checkout, Klarna Payments, Dibs Easy, Collector, Afterpay, Ecster Pay etc. there can be compatibility issues.

• The JS, CSS files is moved around. 
  This can result in that the checkout doesn’t appear at all.
• You are minifying/concatenate/caching HTML, CSS and JS-files.
  This can result in double orders, wrong Information in the orders etc.

• Autoptimize
• LiteSpeed Cache
• SG Optimizer
• WP Fastest Cache
• WP Rocket
• W3 Total Cache

The summary of this is that if you use a Iframe-based checkout you should NOT do anything with the HTML, JS or CSS on the cart/checkout page.