Discount code is applied twice when the user goes back from the payment page
- Environment
- Staging build 2.14.0 · Chrome 130 on Windows 11 · test account qa.buyer3
- Steps
- Add an item priced ₹1,250 to the cart.
- Apply the code SAVE10 on the cart page.
- Continue to payment, then press the browser Back button.
- Continue to payment again.
- Expected
- One 10% discount. Order total ₹1,125.
- Actual
- The discount is applied a second time. Order total ₹1,012.50.
- How often
- 5 out of 5 attempts. Not reproducible on the live site, which is on build 2.13.
- Evidence
- Screen recording and network log attached. The /cart/apply-coupon call fires again on the second visit.
- Impact
- Revenue loss on every affected order once 2.14 ships. Blocks the release.