Shopify POS UI Extensions API v2026-07 Adds Component-Level Discount Allocations

Shopify has released POS UI Extensions API version 2026‑07, adding component‑level discount allocation data to product bundle components in cart line items. The new property, components[].discountAllocations, can be accessed via shopify.cartLineItem.components?.[0]?.discountAllocations and is also present in the Cart API cart state through shopify.cart.current.value.lineItems. Previously, only the parent line item exposed discountAllocations while bundle components only showed tax information, making it hard to calculate component‑level discounts for bundled products. This update is additive; apps using API 2026‑04 or earlier do not need to change, but those adopting 2026‑07 must handle the new property and its possible absence or emptiness. The LineItem shape remains unchanged, so existing code that reads line items can now also read component discount allocations without modification. Developers should update their POS UI Extensions to read components[].discountAllocations for accurate reporting, tax, and compliance calculations. The change does not affect other API endpoints or introduce breaking changes. Documentation for the new API can be found on Shopify’s dev site under the Cart Line Item API reference.