I am playing with Google\'s OAuth 2.0 Playground using my own personal Google account, but I cannot seem to recover my Gmail address using the playground.
Please see my answer here to the identical issue:
how to get email after using google OAuth2 in C#?
In your scopes variable. Use the value "email" not the
full https address. Scope keywords in the web link are separated by spaces. I solve your issue with scopes written as: profile email openid.