I tried this app (it’s been renamed to “MS ‑ Coupon Discount On Cart”) and found several issues with it:
- Users can’t press “Enter” to apply discount codes
- Incorrect calculation of free shipping discounts
- No support for stacking discounts
- Discounts applied at checkout not reflected when returning to cart page
- Checkout discounts overridden by cart discounts
- Invalid subtotal calculation when automatic discounts are applied
To be clear, not just this app had issues like this, also 5 out of the 6 other discount apps I tested had various issues, see my detailed review at https://appreviewhq.com/shopify-discount-app-review-2024. The only app I found that worked with stacked discounts and free shipping was https://apps.shopify.com/discount-before-checkout.