diff --git a/plinth/modules/wireguard/templates/wireguard.html b/plinth/modules/wireguard/templates/wireguard.html
index 73e56bce6..af7551b26 100644
--- a/plinth/modules/wireguard/templates/wireguard.html
+++ b/plinth/modules/wireguard/templates/wireguard.html
@@ -59,7 +59,7 @@
     {% if not server.public_key %}
       <form method="post" action="{% url 'wireguard:enable-server' %}">
         {% csrf_token %}
-        <button type="submit" class="btn btn-primary"
+        <button type="submit" class="btn btn-primary btn-start-server"
                 title="{% trans 'Start WireGuard Server' %}">
           <span class="fa fa-rocket" aria-hidden="true"></span>
           {% trans "Start WireGuard Server" %}
diff --git a/plinth/modules/wireguard/tests/test_functional.py b/plinth/modules/wireguard/tests/test_functional.py
index df5b0ec37..02f60a36d 100644
--- a/plinth/modules/wireguard/tests/test_functional.py
+++ b/plinth/modules/wireguard/tests/test_functional.py
@@ -67,6 +67,11 @@ class TestWireguardApp(functional.BaseAppTests):
     def _add_client(browser, key):
         """Add a client."""
         functional.nav_to_module(browser, 'wireguard')
+        # Start the server on FreedomBox, if needed.
+        start_server_button = browser.find_by_css('.btn-start-server')
+        if start_server_button:
+            start_server_button.first.click()
+
         browser.find_by_css('.btn-add-client').first.click()
         browser.find_by_id('id_public_key').fill(key)
         functional.submit(browser, form_class='form-add-client')