IssueTracker

Hi,

I've setup a service account and enabled domain-wide delegation with all scopes for the GMail API.
My service account json key includes the "subject" field using the email address from an admin account as its value.
When I'm trying to fetch the messages using the "user.messages" resource with the "list" method I get the messages back for this user.
If I try to fetch the messages for a different user I get the error below:

{
 "error": {
  "errors": [
   {
    "domain": "global",
    "reason": "forbidden",
    "message": "Delegation denied for admin@gmail.com"
   }
  ],
  "code": 403,
  "message": "Delegation denied for admin@gmail.com"
 }
}

This feels related to https://issuetracker.google.com/issues/36760064.

Best Regards,
Tim