simplification: use a standard link, not javascript

templates/web/en/home.tt2.html

-<script type="text/javascript">
-
-$(function() {
-    $('#start_testing').on('click',function() {
-        window.location.href='[% app.url %]?action=select_sp';
-    });
-});
-
-</script>
-
 
 <div class="row">
 <h2>[% app.name %]?</h2>
@@ -17,11 +7,9 @@ accounts with different profiles to validate the behaviour and test
 federated login. The test accounts can only be used to access own services. <a href="presentation.html">Learn more about this service...</a>
 </p>
 <h3>Start testing your eduGAIN service</h3>
-<p>
-To start testing your own eduGAIN service, start by selecting the
-Service Provider you are administrator for.
-</p>
-<p class="align-center"><button id="start_testing">Go on testing the service</button></p>
+<p>To start testing your own eduGAIN service, start by selecting the Service
+Provider you are administrator for.</p>
+<p class="align-center"><a href="?action=select_sp" class="button">Go on testing the service</a></p>
 
 <h3>[% app.name %] basics</h3>
 <p>

templates/web/fr/home.tt2.html

-<script type="text/javascript">
-
-$(function() {
-    $('#start_testing').on('click',function() {
-        window.location.href='[% app.url %]?action=select_sp';
-    });
-});
-
-</script>
-
-
 <div class="row">
 <h2>[% app.name %]?</h2>
 <p>[% app.name %] allows administrators of a Service
@@ -17,11 +6,8 @@ accounts with different profiles to validate the behaviour and test
 federated login. The test accounts can only be used to access own services. <a href="presentation.html">Learn more about this service...</a>
 </p>
 <h3>Start testing your eduGAIN service</h3>
-<p>
-To start testing your own eduGAIN service, start by selecting the
-Service Provider you are administrator for.
-</p>
-<p class="align-center"><button id="start_testing">Go on testing the service</button></p>
+<p>To start testing your own eduGAIN service, start by selecting the Service Provider you are administrator for.</p>
+<p class="align-center"><a href="?action=select_sp" class="button">Go on testing the service</a></p>
 
 <h3>[% app.name %] basics</h3>
 <p>