I want to customize my Add To Cart button, and have uploaded a new version to my language override directory (as stated in the FAQs), and have changed my button_names.php page respectively. I've noticed however, that it's not the 'button_add_to_cart' button that I see on my page at the moment, it's the 'button_in_cart' button.

What's the difference between these two? Where would the Add to Cart button show up if not there? Can I change this setting in the admin?

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