We have created a custom basemap using the Vector Tile Style Editor.
This tile layer was then added and saved as a web map and shared with our custom basemap gallery group.
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Our AGO site is configured to use this as the default basemap in or organization.
As you can see, there are only 2 layers in this web map: the vector tile layer and hillshade:
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If I then 'Open in Map Viewer', the layers are as expected:
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However, if I create a new/blank/empty Web Map, the custom basemap layers load as expected, but the World Topographic map is added as well. So now I have two overlapping basemaps and need to manually remove the world topo one.
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The same behavior is observed in ArcGIS Pro when creating a new map:
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Why is the Esri basemap loading by default in addition to our custom basemap when our AGO site is configured to use the custom basemap as the default?
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