Thread:Project:Support desk/Help with extension:Facebook/reply

You should probably report the problem to the Extension talk:Facebook page since it's maintainer probably isn't aware of your report here.

Besides that, the error message suggests a failure when retrieving information from facebook. If the problem is that it can't connect, the issue may be that your server can't resolve DNS names or it doesn't allow-url-fopen, this second one is common in some web hostings.