Currently the map widget only allows the use of markers. Expanding the functionality of the map widget, or creating a new one that could handle polygon coordinates in the Leaflet GeoJSON format would be a great addition, expanding the capabilities of grist.
"coordinates": [[
[-109.05, 41.00],
[-102.06, 40.99],
[-102.03, 36.99],
[-109.04, 36.99],
[-109.05, 41.00]
]]
Supporting this kind of figures:

Currently the map widget only allows the use of markers. Expanding the functionality of the map widget, or creating a new one that could handle polygon coordinates in the Leaflet GeoJSON format would be a great addition, expanding the capabilities of grist.
Supporting this kind of figures: