external-link-square icon renamed in FA5

modules/admin/templates/federation.twig

@@ -45,7 +45,7 @@
                 <a class="pure-button copy hljs" data-clipboard-target="#url-{{ key }}"
                    title="{% trans %}Copy to clipboard{% endtrans %}"><span class="fa fa-copy"></span></a>
                 <a class="pure-button hljs" href="{{ set.url }}">
-                  <span class="fa fa-external-link-square"></span>
+                  <span class="fa fa-external-link-square-alt"></span>
                 </a>
               </div>
               <code id="url-{{ key }}" class="code-box-content">{{ set.url }}</code>