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As shown in the screenshot above, the “Offer Discount” is not considered a "cart item" (as a product, for example). We can think of this as an "informative card"
The "Offer Discount" will have a discount applied to the final price of the cart (total cart). The type of discount can be “Amount” (absolute value discounted) or “Percentage”
For the screenshot above we can imagine that we have a Offer Discount of 50% applied. The sum of prices and taxes will be something close to 20 but the final value will be half of that.
PS: Please disregard if the values are not exact in the screenshot above, as this comes from a dev environment and we have some problems with value consistency. The important thing here is the idea/behavior.
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