Good. First of all, this is a very clear error message. Just see how many developers skip this, including myself. Look at the screenshot here, please.

Under Products> Facebook Login> Settings
or just go to this address (replace YOUR_APP_ID with the identifier of your application, lol):
https://developers.facebook.com/apps/YOUR_APP_ID/fb-login/settings/
If you are working on localhost:3000 , make sure you have https://localhost:3000/auth/facebook/callback
Of course, you do not need to have real-time status (the green switch in the upper right corner), but in my case I am now deploying to heroku and will soon replace localhost:3000 with https://myapp.herokuapp.com/auth/facebook/callback
Of course, I will update the URLs in Settings / General & Settings / Advanced, and add the privacy policy URL in the main section.
I assume that you set up initializer / devise.rb correctly if you use devise and you have the correct facebook gem 'omniauth-facebook', '~> 4.0' installed gem 'omniauth-facebook', '~> 4.0' and gem 'omniauth', '~> 1.6' , and you have the necessary columns in your user table, such as uid, image, and provider. It.
Elias Glyptis Jun 01 '19 at 17:14 2019-06-01 17:14
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