Thanks @Liam! I did try that but it doesn't return any results. According to the docs this is a "List of the shop's locations that support in-store pickup." I need to be able to fetch all locations, not just those that support in-store pickup.
Hi again Jamalali,
You could try setting up an approach where you access the locations API (which would return a list of active inventory locations) with a backend service and then from within the Checkout UI Extension, you could make AJAX/fetch requests to your backend service to fetch location info.