Facebook Error: Can't Load URL: The domain of this URL isn't included in the app

Am receiving the password error after changing the Facebook password. Tried to follow the instructions in section 2.9 of the FAQ but after clicking “Re-authorize Your Facebook Account”, Facebook gives this error:

“Can’t Load URL: The domain of this URL isn’t included in the app’s domains. To be able to load this URL, add all domains and subdomains of your app to the App Domains field in your app settings.”

How do I resolve this, and what domain is it wanting me to add?

Thank you.

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