Checkout.liquid
How to enable Shopify Plus checkout.liquid customizations
My upsell isn’t showing in my checkout, how do I get it to show?
How to upsell to a subscription in checkout
How do I test a checkout upsell on a draft theme?
How to design checkout upsells with custom CSS
How do I make my checkout upsells show outside of the collapsed Order Summary on mobile?
How to show an upsell on a specific page of the checkout
How to manually install the checkout widget to the checkout.liquid theme file