diff --git a/admin/settings/users.php b/admin/settings/users.php
index <HASH>..<HASH> 100644
--- a/admin/settings/users.php
+++ b/admin/settings/users.php
@@ -25,7 +25,7 @@ if ($hassiteconfig
                                             get_string('alternatelogin', 'auth', htmlspecialchars(get_login_url())), ''));
     $temp->add(new admin_setting_configtext('forgottenpasswordurl', get_string('forgottenpasswordurl', 'auth'),
                                             get_string('forgottenpassword', 'auth'), ''));
-    $temp->add(new admin_setting_configtextarea('auth_instructions', get_string('instructions', 'auth'),
+    $temp->add(new admin_setting_confightmleditor('auth_instructions', get_string('instructions', 'auth'),
                                                 get_string('authinstructions', 'auth'), ''));
     $temp->add(new admin_setting_configtext('allowemailaddresses', get_string('allowemailaddresses', 'admin'), get_string('configallowemailaddresses', 'admin'), '', PARAM_NOTAGS));
     $temp->add(new admin_setting_configtext('denyemailaddresses', get_string('denyemailaddresses', 'admin'), get_string('configdenyemailaddresses', 'admin'), '', PARAM_NOTAGS));
auth config: MDL-<I> Use the HTML editor to edit the login page authentication instructions

They are actually displayed as HTML, but they are edited through a plain
text area control instead.

Forward-ported from MOODLE_<I>_STABLE