step 1:
step 2:
url at which the error shows up:
https://www.facebook.com/v2.6/dialog/oauth?
client_id=admin&
state=123123123123123123123& (example alphanumeric code)
response_type=code&
sdk=php-sdk-5.4.4&
redirect_uri=http%3A%2F%2F<my_website_host_here>%2Fwp-admin%2Fadmin.php%3Fpage%3Dinstant-articles-wizard&
scope=pages_manage_instant_articles%2Cpages_show_list