The Basemap Gallery displays all ESRI basemaps, partner basemaps, and user basemaps. When the Basemap Gallery is loaded, it will, by default, search for the following basemap attributes:
tags:esri_basemap OR tags:partner_basemap OR tags:user_basemap OR tags:basemap
This section of the Lucity Web Help Guide explains how to control search results in the Basemap Gallery.
When users click the Swap Basemaptool in the Lucity Webmap, the Basemap Gallery appearas. By default, the Portal Basemap Gallery is enabled and the system displays the configured list of basemaps.