app/views/user_settings/authentication.html.erb
<% content_for :my_account_content do %>
<h2><%= t('.title') %></h2>
<%= display_link_to_connect_with_provider(:facebook, 'facebook-square', t('.providers.link_facebook'), t('.providers.linked_facebook')) %>
<% end %>
<%= render 'common/my_account' %>