I linked a map to use for offline instances, and see this error:
Some documents say to make sure the map is in WGS 1984 Web Mercator (auxiliary sphere), which this is.
Anyone else come across this?
EPSG Geodetic Parameter Dataset - Wikipedia
EPSG:4326 is a datum for the geographic coordinate system
EPSG:3857 is the web mercator projection of 4326 data