InventorySwatchesFrontendUi adds info about salable quantity to configurable product in case a user choose some
specific product variation.
This module is a part of the new inventory infrastructure. The Inventory Management overview describes the MSI (Multi-Source Inventory) project in more detail.
This module is installed as part of Magento Open Source. It may be disabled if the Inventory Management UI is provided by a 3rd-party system or if you run a headless version of Magento.