diff --git a/plinth/modules/diagnostics/templates/diagnostics_app.html b/plinth/modules/diagnostics/templates/diagnostics_app.html
index 65650f9a9..2c4cff90e 100644
--- a/plinth/modules/diagnostics/templates/diagnostics_app.html
+++ b/plinth/modules/diagnostics/templates/diagnostics_app.html
@@ -9,7 +9,7 @@
 
   <h2>{% trans "Diagnostic Results" %}</h2>
 
-  <div class="row align-items-center justify-content-between">
+  <div class="d-flex align-items-center justify-content-between">
     <h3>{% blocktrans %}App: {{ app_name }}{% endblocktrans %}</h3>
 
     {% if show_repair %}
diff --git a/plinth/modules/diagnostics/templates/diagnostics_full.html b/plinth/modules/diagnostics/templates/diagnostics_full.html
index 30ebd65b8..27d14cb06 100644
--- a/plinth/modules/diagnostics/templates/diagnostics_full.html
+++ b/plinth/modules/diagnostics/templates/diagnostics_full.html
@@ -33,7 +33,7 @@
   {% if results %}
     <h3>{% trans "Results" %}</h3>
     {% for app_id, app_data in results.results.items %}
-      <div class="row align-items-center justify-content-between">
+      <div class="d-flex align-items-center justify-content-between">
         <h4>
           {% blocktrans trimmed with app_name=app_data.name %}
             App: {{app_name}}