Not all the Azure AD attributes can be used in PowerApps. The O365 Users connector is limited in what it surfaces. This is a real impediment to developing custom apps in SharePoint Online. Currently, I can add additional (extension attributes) properties to the User Profile Service using the PnP solution, and with InfoPath retrieve extension attributes to populate a form. However, if the direction by Microsoft is to replace InfoPath with PowerApps, then it's critical to provide an avenue to inspect all the same AD properties I can access in an on-prem environment. The properties exist in Azure AD, why is there a limitation as to which ones can be queried? Why should companies be forced to consider evaluating the added costs of monthly subscritions to third-party connectors when the data is already there? At least allow the O365 connector to surface all extension attributes as well as ALL commonly used properties, NOT a subset. Or, allow a simplified way for someone to inherit from the O365 Connector and build their own to include the additional AD attributes they need included. I couldn't find an example of a custom connector that was created to expose AD extension attributes for consumption by PowerApps / Flow.