Users endpoint now supports cursor-based pagination

Previously, the Users endpoint returned the full list of all staff accounts on a shop.

For shops with a large number of users, this could lead to response timeouts, as the list was simply too large to return within a reasonable timeframe.

To make this data more manageable, we've enabled the same cursor-based-pagination found in other areas of the Admin API on the Users endpoint.

To learn more about pagination support in REST Admin APIs, please check out this tutorial.