SharePoint on-prem embed authentication issue

[Anonymous]

I have an issue when trying to embed Power BI tiles/reports in SharePoint 2013 on-prem. The users are automatically signed in to SharePoint (using ADFS), but they are not automatically signed in to Power BI, which makes them need to re-authenticate to see the embedded Power BI content.

We are using the URL "https://login.windows.net/common/oauth2/authorize" to authenticate and request the Power BI token. Maybe we should point the users directly to "https://ouradfsserverurl/adfs/ls" instead, but I don't think that should be the case. ADFS is configured to use auto acceleration to Office 365. Note that this scenario works fine (the users does not need to re-authenticate) when using SharePoint online, but not SharePoint on-prem. Any clues?

[stevo]

Slightly off topic but are you allowed to embed into an on-prem sharepoint site? According to the terms its not allowed to be used for internal applications:

https://azure.microsoft.com/en-us/pricing/details/power-bi-embedded/

[Anonymous]

This is not related to Power BI Embedded. This is regarding the "traditional" APIs for integrating tiles and reports into apps.