With Map Viewer Classic, it's possible for users to add additional layers to a web map without signing in by clicking the 'Modify Map' option. This functionality doesn't appear to be available in the New Map Viewer and isn't mentioned in the functionality guide blog post or the New Map Viewer documentation, as it was in the Map Viewer Classic documentation (second 'Note' bubble on the page).
Is there a reason for this? Are there plans to implement it later?
-Aaron
