Adding more collaborators to your custom map is much easier now. You can add multiple users at once (just separate individual user emails with comma)
New Content editor role
The new Content editor role makes collaborating on content for your map easier than ever! The Content editor can only access & manage places, routes and polygons in your map. That means, it can edit or delete any objects added by other users, but can’t touch any settings of your map. To make this feature even more useful, we added an option to select categories which the content editor can access.