Node red dashboard ** unauthorized **

Good morning
sorry for the trouble but I saw from the forum that someone managed to solve a problem with mit app inventor on the node red dashboard
my problem is that the http of the node red page is protected by use and password, when with webview1 I go to load the page it tells me that it is ** unauthorized ** it is as if it could not load the login credentials popup
Can you give me a hand

This discussion WebViewer cannot display Node-Red dashboards ?

It uses the WebView Custom extension, not the standard WebVIewer.