Single Sign On (SSO) from within an Office Web Add-in (ASP.NET Core / Blazor)

[gszdev]

Hi,
is it possible to use the access token from an Office Web Add-in for accessing SharePoint Online through PnP.Core?

Sample for ASP.NET Office Add-in (SSO)
Office API (JavaScript): OfficeRuntime.auth.getAccessToken

Which settings have to be set for the app registration (API-Permissions, Expose API, Scopes, ...) and how can the Office access token be used for PnP.Core?