Failed Silent Auth - should there be a javascript popup in my client?

Further to looking into why my silent auth fails, i could not see the response in chrome because it just shows “Failed to load response data”

so i cut and pasted the request into postman (did not set any of the other headers, not sure if I should have, probably) like this

[https://needuum.auth0.com/authorize?client_id=

and i get this body response:
which sure looks like ti wants to do some window opening and message displaying, but nothing has been displayed in my browser after the failures, so then why send all of this back ???

Authorization Response

yeah the security here stripped out the response

but it was several paragraphs of javascript wanting to display mesages in windows linked to event listeners and so forth