I created a single display operation view using a web map with one feature service.
This feature service is hosted on premise on my ArcGIS Server, using ArcGIS Web adapter to expose this service outside of the firewall.
I then shared this web map and operation view with Public.
I then try to open the operation view in a browser by using the URL:
But then it asks my to login to our ArcGIS Online site. Why? This is a Public Operation view, using a Public web map.