In order to use this option, follow these steps:
1) Log-in to your facebook account and visit https://developers.facebook.com/apps.
2) Click on Create New App button and in App Name textbox, enter your website title or name. Click continue and submit the security image check.
3) Under the heading Select how your app integrates with Facebook, select Website with Facebook Login and copy and paste undermentioned URL (with a question mark at the end):
4) Click Save Changes button at the bottom of facebook page.
5) Copy and paste App ID and App Secret of the newly created application in the Facebook App ID and Facebook App Secret text-boxes respectively.
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