Facebook OAuth redirect URIs for both canvas and website Unity game versions

I have developed a Unity game that enables users to login with their Facebook account.

The game has two versions

1. Facebook canvas version to play inside Facebook http://ift.tt/1IN3dfy. We configured our facebook app to use the unity integration so we supply a direct path to the unity3d file.
2. public website version http://www.MyGame.com

Recently the website version facebook login stopped working.

We traced the problem to the Settings|Advanced|Client OAuth Settings. When the Web OAuth Login setting is disabled, the web version can't login to facebook.

If we enable this setting, then Facebook requires us to whitelist redirect uris.

We whitelisted the web version uri and it works, we are able again to login to Facebook from the website. But the facebook version stopped working.

It seems that we also need to whitelist the facebook canvas version redirect uri. But we don't know what it is. We do not supply it to the sdk. We tried different values, e.g. the location where our .untiy3d file is deployed but nothing worked.

It is strange to me that we suddenly require the WebOAuth Login switch. Can someone confirm this?

Is there a redirect URI I can whitelist for the facebook canvas version to work?

I am using FacebookUnitySDK6.0 with Unity4.6.6 and I must have the 'Unity integration' setting enabled.