Use the component helper for rendering the timezone dropdown in admins page.

application/controllers/Admins.php

@@ -70,7 +70,7 @@ class Admins extends EA_Controller {
             'page_title' => lang('admins'),
             'active_menu' => PRIV_USERS,
             'user_display_name' => $this->accounts->get_user_display_name($user_id),
-            'timezones' => $this->timezones->to_array(),
+            'timezones' => $this->timezones->to_grouped_array(),
             'privileges' => $this->roles_model->get_permissions_by_slug($role_slug),
         ]);
 

application/views/pages/admins.php

@@ -177,7 +177,9 @@
                             <?= lang('timezone') ?>
                             <span class="text-danger">*</span>
                         </label>
-                        <?= render_timezone_dropdown('id="timezone" class="form-control required"') ?>
+                        <?php component('timezone_dropdown', 'id="timezone" class="form-control required"', [
+                            'timezones' => vars('timezones')
+                        ]) ?>
                     </div>
 
                     <br>