diff --git a/plinth/modules/backups/templates/backups_repository.html b/plinth/modules/backups/templates/backups_repository.html
index e7e3e7ce8..03d31eb61 100644
--- a/plinth/modules/backups/templates/backups_repository.html
+++ b/plinth/modules/backups/templates/backups_repository.html
@@ -6,7 +6,7 @@
 
 <div class="table-responsive">
   <table class="table" id="archives-list">
-    <thead class="collapsible-button" data-toggle="collapse" data-target="#{{ uuid }}">
+    <thead class="collapsible-button" data-bs-toggle="collapse" data-bs-target="#{{ uuid }}">
       <tr>
         <th colspan="2">
           <span class="fa fa-chevron-right fa-fw" aria-hidden="true"></span>
diff --git a/plinth/modules/backups/templates/verify_ssh_hostkey.html b/plinth/modules/backups/templates/verify_ssh_hostkey.html
index cdbdb260d..ab471315c 100644
--- a/plinth/modules/backups/templates/verify_ssh_hostkey.html
+++ b/plinth/modules/backups/templates/verify_ssh_hostkey.html
@@ -41,7 +41,7 @@
       <section>
         <p>
           <a class="btn btn-default collapsed collapsible-button"
-             data-toggle="collapse" href="#help" aria-expanded="false">
+             data-bs-toggle="collapse" href="#help" aria-expanded="false">
             <span class="fa fa-chevron-right fa-fw" aria-hidden="true"></span>
             {% trans "How to verify?" %}
           </a>
diff --git a/plinth/modules/firewall/templates/firewall.html b/plinth/modules/firewall/templates/firewall.html
index 616b12d8b..14b46fc97 100644
--- a/plinth/modules/firewall/templates/firewall.html
+++ b/plinth/modules/firewall/templates/firewall.html
@@ -28,8 +28,8 @@
             <tr>
               <td class="app-name">
                 <a class="dropdown-toggle" href="#"
-                   data-toggle="collapse" role="button"
-                   data-target=".{{component.component_id}}"
+                   data-bs-toggle="collapse" role="button"
+                   data-bs-target=".{{component.component_id}}"
                    aria-expanded="false"
                    aria-controls="{{component.component_id}}">
                   {{ component.name }}</a>
diff --git a/plinth/modules/help/templates/help_contribute.html b/plinth/modules/help/templates/help_contribute.html
index add270602..745bb60b1 100644
--- a/plinth/modules/help/templates/help_contribute.html
+++ b/plinth/modules/help/templates/help_contribute.html
@@ -53,7 +53,7 @@
   </p>
   <p>
     <a class="btn btn-default collapsed collapsible-button" role="button"
-       data-toggle="collapse" href="#collapse-issues" aria-expanded="false"
+       data-bs-toggle="collapse" href="#collapse-issues" aria-expanded="false"
        aria-controls="collapse-issues">
       <span class="fa fa-chevron-right fa-fw" aria-hidden="true"></span>
       {% trans "Show issues" %}
diff --git a/plinth/modules/upgrades/templates/upgrades_configure.html b/plinth/modules/upgrades/templates/upgrades_configure.html
index 976dfb940..1fe437a71 100644
--- a/plinth/modules/upgrades/templates/upgrades_configure.html
+++ b/plinth/modules/upgrades/templates/upgrades_configure.html
@@ -127,7 +127,7 @@
   {% if log %}
     <p>
       <a class="btn btn-default collapsed collapsible-button" role="button"
-         data-toggle="collapse" href="#collapse-log" aria-expanded="false"
+         data-bs-toggle="collapse" href="#collapse-log" aria-expanded="false"
          aria-controls="collapse-log">
         <span class="fa fa-chevron-right fa-fw" aria-hidden="true"></span>
         {% trans "Show recent update logs" %}
diff --git a/plinth/modules/users/templates/users_update.html b/plinth/modules/users/templates/users_update.html
index a0de5fd60..d52477c8c 100644
--- a/plinth/modules/users/templates/users_update.html
+++ b/plinth/modules/users/templates/users_update.html
@@ -42,7 +42,7 @@
               Delete user <em>{{ username }}</em> and all the user's files?
             {% endblocktrans %}
           </h5>
-          <button type="button" class="close" data-dismiss="modal"
+          <button type="button" class="close" data-bs-dismiss="modal"
                   aria-label="{% trans 'Close' %}">
             <span aria-hidden="true">&times;</span>
           </button>
@@ -58,7 +58,7 @@
           <button type="button" class="btn btn-danger confirm">
             {% trans "Delete user and files" %}
           </button>
-          <button type="button" class="btn btn-secondary" data-dismiss="modal">
+          <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">
             {% trans "Cancel" %}
           </button>
         </div>
diff --git a/plinth/templates/apps.html b/plinth/templates/apps.html
index a84991f7e..d9efd8b17 100644
--- a/plinth/templates/apps.html
+++ b/plinth/templates/apps.html
@@ -25,7 +25,7 @@
             {% endfor %}
           </div>
           <input id="add-tag-input" type="search" class="form-control dropdown-toggle"
-                 data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"
+                 data-bs-toggle="dropdown" aria-haspopup="true" aria-expanded="false"
                  autocomplete="off" placeholder="{% trans "Search with tags" %}">
           <div class="dropdown-menu" aria-labelledby="add-tag-input">
             <ul class="dropdown-items list-unstyled">
diff --git a/plinth/templates/base.html b/plinth/templates/base.html
index 9c532ec3a..603551c69 100644
--- a/plinth/templates/base.html
+++ b/plinth/templates/base.html
@@ -100,8 +100,8 @@
         {% endblock %}
 
         {% block mainmenu_toggler %}
-          <button class="navbar-toggler" type="button" data-toggle="collapse"
-                  data-target="#navbar-collapse" aria-controls="navbar-collapse"
+          <button class="navbar-toggler" type="button" data-bs-toggle="collapse"
+                  data-bs-target="#navbar-collapse" aria-controls="navbar-collapse"
                   aria-expanded="false" aria-label="Toggle navigation">
             <span class="fa fa-bars"></span>
           </button>
@@ -151,7 +151,7 @@
 
                 <li id="id_user_menu" class="nav-item dropdown">
                   <a href="{% url 'users:edit' request.user.username %}"
-                     class="nav-link dropdown-toggle" data-toggle="dropdown"
+                     class="nav-link dropdown-toggle" data-bs-toggle="dropdown"
                      role="button" aria-expanded="false" aria-haspopup="true"
                      id="id_user_menu_link">
                     <i class="fa fa-user nav-icon"></i>
diff --git a/plinth/templates/clients-button.html b/plinth/templates/clients-button.html
index e36b05b26..49233dab0 100644
--- a/plinth/templates/clients-button.html
+++ b/plinth/templates/clients-button.html
@@ -19,7 +19,7 @@
     {% endif %}
 
     {% if client_platforms.web|length > 1 or client_platforms.other %}
-      <button type="button" data-toggle="collapse" data-target="#clients"
+      <button type="button" data-bs-toggle="collapse" data-bs-target="#clients"
               class="btn btn-default collapsed collapsible-button">
         <span class="fa fa-chevron-right fa-fw" aria-hidden="true"></span>
         {% trans "Client Apps" %}
diff --git a/plinth/templates/help-menu.html b/plinth/templates/help-menu.html
index 99d01524c..36bdd6da6 100644
--- a/plinth/templates/help-menu.html
+++ b/plinth/templates/help-menu.html
@@ -6,7 +6,7 @@
 
 <li id="id_help_menu" class="dropdown nav-item">
   <a href="{% url 'help:index' %}" title="{% trans "Help" %}"
-     class="nav-link dropdown-toggle" data-toggle="dropdown"
+     class="nav-link dropdown-toggle" data-bs-toggle="dropdown"
      role="button" aria-expanded="false" aria-haspopup="true"
      id="id_help_menu_link">
     <span class="fa fa-question-circle nav-icon"></span>
diff --git a/plinth/templates/notifications-dropdown.html b/plinth/templates/notifications-dropdown.html
index 4e703c5a1..f016fd6f0 100644
--- a/plinth/templates/notifications-dropdown.html
+++ b/plinth/templates/notifications-dropdown.html
@@ -9,9 +9,9 @@
 {% if notifications %}
   <li class="nav-item dropdown notifications-dropdown">
     <a href="#" title="{% trans "Notifications" %}"
-       class="nav-link dropdown-toggle" data-toggle="dropdown"
+       class="nav-link dropdown-toggle" data-bs-toggle="dropdown"
        role="button" aria-expanded="false" aria-haspopup="true"
-       data-target=".notifications">
+       data-bs-target=".notifications">
       <span class="fa fa-bell nav-icon"></span>
       <span class="badge rounded-pill
         {% if notifications_max_severity == 'exception' or notifications_max_severity == 'error' %}
diff --git a/plinth/templates/toolbar.html b/plinth/templates/toolbar.html
index 26d19b314..e5b13a3a1 100644
--- a/plinth/templates/toolbar.html
+++ b/plinth/templates/toolbar.html
@@ -23,9 +23,9 @@
 
       {% if has_diagnostics or show_uninstall or has_backup_restore %}
         <!-- Single button -->
-        <div class="btn-group button-secondary">
+        <div class="btn-group button-secondary dropdown">
           <button type="button" class="btn btn-default dropdown-toggle"
-                  data-toggle="dropdown" aria-haspopup="true"
+                  data-bs-toggle="dropdown" aria-haspopup="true"
                   aria-expanded="false" id="id_extra_actions_button">
             <span class="fa fa-cog" aria-hidden="true"></span>
           </button>
diff --git a/plinth/views.py b/plinth/views.py
index 84fdca4b5..1b4337f93 100644
--- a/plinth/views.py
+++ b/plinth/views.py
@@ -71,7 +71,7 @@ def messages_error(request, message, exception):
         collapse_id = 'error-details-' + str(random.randint(0, 10**9))
         message = format_html(
             '{message} <a href="#" class="dropdown-toggle" '
-            'data-toggle="collapse" data-target="#{collapse_id}" '
+            'data-bs-toggle="collapse" data-bs-target="#{collapse_id}" '
             'aria-expanded="false" aria-controls="{collapse_id}">'
             'Details</a><pre class="collapse" '
             'id="{collapse_id}"><code>{html_message}</code></pre>',