Forgive any lack of the correct terminology. When I open a map and zoom to the world scale in ARCGISonline, I get a flat earth. If I open Pro and zoom to the world scale, I get the three quarter earth shape. I thought this could be resolved by reprojecting the three quarter earth into Mercator, but the geoprocessing tool will not let me reproject the basemap. The firefly basemap opens as a 'flat earth' in Pro. Thank you.