Missing scope error on Google authentication callback using Node.js/Passport

This error occurs on Heroku (production) only, not on local. I have tried both:

passport.authenticate('google', { scope: 'http://ift.tt/18tkxUQ http://ift.tt/IX6Fa1' })

And,

passport.authenticate('google', { scope: ['profile', 'email'] })

Whether the scope is an array, or a space-delimited string.

When I go to the Google authentication link, scope IS in the URL. There is no difference in the one generated in my live production app.

But I still get:

Error 400

Error: invalid_request

Missing required parameter: scope