Got it. This is for a video overlay and so it’s against the rules to request oAuth permissions for a user. Any thoughts on how we can retrieve a display_name for an extension without requiring oAuth? Guess this could/should be asked in #extensions.
Update: Tracing this further, it seems that the opaque ID isn’t intended to be used for looking up profile data which is why I keep running into a wall and that once the user grants identity link a numerical ID is returned to the onAuthorized callback (which doesn’t appear to be the case yet, still troubleshooting.) I can get a display_name with the numerical ID no problem, so just need to figure out why I can’t get that yet after granting identity link with a test account.
Update 2: 6 hours later of troubleshooting. Opaque ID is used for tracking a user session. Once a user grants identity link the numerical user_id is sent from onAuthorized callback as part of the “token” which you can send to the EBS to decode. After, send a query to Helix API with auth bearer token and client ID to get the user data, then return display_name.