openproject/app/views/account/_auth_providers.html.erb

<%
# Remove this ugly hack when creating an authentication plugin.
#
# This hack is required as we don't have a way to list all active
# Omniauth Providers without a patch.
#
# See
# * https://www.openproject.org/work_packages/7192
# * http://stackoverflow.com/questions/13112430/find-loaded-providers-for-omniauth
auth_provider_html = call_hook :view_account_login_auth_provider
%>
<% if auth_provider_html.strip != '' %>
  <div class="login-auth-providers">
    <h3 class="login-auth-providers-title"><span>
      <%= I18n.t('account.login_with_auth_provider')%>
    </span></h3>
    <div class="login-auth-provider-list">
      <%= auth_provider_html %>
    </div>
  </div>
<% end %>