I uploaded a GEOJSON on the main arcgisonline content page.
Open Map Viewer (New, because for some reason the Classic map viewer is "unable" to view a simple uploaded GEOJSON file...)
Now, if I click the "(+)Add" button on the left panel in the map viewer and select "My Content," no layers show up.
However, if I click the "Add" button on the bottom of the layer list, suddenly my layer appears.
Very confusing. Overall the New Map Viewer is not good. It has some great features but the UI is confusing and convoluted.
