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## Cornerstone 6.20.0

Cornerstone 6.20.0 expands backorder and stock-availability messaging across the product page, cart, and account order pages, adds support for bundled (picklist) item inventory, refines the cart shipping layout, and delivers accessibility and bug fixes.

* **Respect `available_to_sell`** — Hides the Sold Out alert and keeps Add to Cart enabled for backorderable products, and disables Add to Cart with a "maximum purchasable quantity" message when the requested quantity exceeds `available_to_sell` (for both simple products and variants)
* **Support `unlimited_backorder`** — Renders the backorder quantity message and availability prompt, and lifts the Add to Cart quantity cap, for products with unlimited backorder
* **Backorder quantity message when clamped** — Shows the "N will be backordered" message when the requested quantity exceeds `available_to_sell` (still clamped by `available_for_backorder`), so shoppers see why the quantity was clamped alongside the "maximum purchasable quantity" message
* **Backorder prompts for picklist products** — Renders backorder prompts for picklist (bundled) products on the PDP
* **Picklist stock validation** — Validates each selected picklist item's `available_to_sell` so Add to Cart is disabled and a "maximum purchasable quantity for \{item} is \{qty}" message is shown when the requested quantity exceeds that item's stock, even when the main product still has enough stock

### Product options

* **Disable-and-hide option values** — Hides option values on the PDP that would complete a "disable and hide" rule for the current selection, and steers the shopper off a default selection that is itself a forbidden combination

### Cart improvements

* **Shipping expectation prompt layout** — Displays the cart shipping expectation prompt on its own full-width row beneath the Shipping label, keeping the shipping cost on the same row as the label
* **Bundled item stock on the cart** — Shows stock positions (on-hand, backordered quantity, and backorder message) for bundled items (pick lists) on the cart page, left-aligned with the quantity adjuster, rendering the section only when there is stock information to display

### Account order pages

* **Backorder prompts on order pages** — Shows backorder prompts (on-hand, backordered quantity, and backorder message) above the options list on the account order pages, and adds a shipping expectation message for backordered orders
* **Backorder prompts for bundled picklist options** — Shows backorder prompts for each bundled picklist option on the order details page, using `linked_bundled_item` data
* **Multi-address "Ship to" copy** — Updates the multi-address order copy to read "Ship to \{address}"

### Accessibility

* **Improved color contrast** — Darkens the low-contrast gray used for buttons, input and checkbox borders, rating stars, and carousel controls to meet accessibility contrast requirements
* **Larger footer tap targets** — Increases the clickable/tap area of footer links for easier interaction
* **Category filter reset announcements** — Fixes the reset-filters live region on the category page so screen readers announce when filters are cleared

### Bug fixes

* **Duplicate payment method ID** — Fixes a duplicate `id="default_instrument"` on the Update Payment Method page
* **`onProductOptionsChanged` event detail** — Swaps the `content` and `data` keys in the `onProductOptionsChanged` event detail so each carries the correct payload