i have XF 1.4.3
My users are unable to pair with the facebook account when they go on External Accounts in User Panel.
The Facebook integration works ok, the test in ACP is ok. The FB sharing etc etc works ok....
Yes, for me it works.
For testing the problem reported by my user , i created new Test account in my forum and new FB account
When i associate the Test user on my site with FB account, i have this screen
In english the message says " App not configured. The developers of this application have not properly configured to access facebook"