The GeoForm web application template is unable to display basemaps from the Basemap Toggle widget when the web map has a custom basemap that is hosted locally in ArcGIS Server.
Last Published: January 19, 2016ArcGIS Online
Bug ID Number
March 20, 2015
March 29, 2021
After review by the development team, it has been determined that this issue is related to a known limitation with the software that lies outside of Esri's control. The issue's Additional Information section may contain further explanation.
This is a known issue with the Basemap Toggle widget.