diff --git a/plugins/user/contactcreator/src/Extension/ContactCreator.php b/plugins/user/contactcreator/src/Extension/ContactCreator.php
index 87e0ac4e015ad..c45396b7be8a1 100644
--- a/plugins/user/contactcreator/src/Extension/ContactCreator.php
+++ b/plugins/user/contactcreator/src/Extension/ContactCreator.php
@@ -10,8 +10,10 @@
 
 namespace Joomla\Plugin\User\ContactCreator\Extension;
 
+use Joomla\CMS\Event\User\AfterSaveEvent;
 use Joomla\CMS\Plugin\CMSPlugin;
 use Joomla\Component\Contact\Administrator\Table\ContactTable;
+use Joomla\Event\SubscriberInterface;
 use Joomla\String\StringHelper;
 
 // phpcs:disable PSR1.Files.SideEffects
@@ -25,24 +27,39 @@
  *
  * @since  1.6
  */
-final class ContactCreator extends CMSPlugin
+final class ContactCreator extends CMSPlugin implements SubscriberInterface
 {
+    /**
+     * Returns an array of events this subscriber will listen to.
+     *
+     * @return array
+     *
+     * @since   __DEPLOY_VERSION__
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onUserAfterSave' => 'onUserAfterSave',
+        ];
+    }
+
     /**
      * Utility method to act on a user after it has been saved.
      *
      * This method creates a contact for the saved user
      *
-     * @param   array    $user     Holds the new user data.
-     * @param   boolean  $isnew    True if a new user is stored.
-     * @param   boolean  $success  True if user was successfully stored in the database.
-     * @param   string   $msg      Message.
+     * @param   AfterSaveEvent $event  The event instance.
      *
      * @return  void
      *
      * @since   1.6
      */
-    public function onUserAfterSave($user, $isnew, $success, $msg): void
+    public function onUserAfterSave(AfterSaveEvent $event): void
     {
+        $user    = $event->getUser();
+        $isnew   = $event->getIsNew();
+        $success = $event->getSavingResult();
+
         // If the user wasn't stored we don't resync
         if (!$success) {
             return;
diff --git a/plugins/user/joomla/src/Extension/Joomla.php b/plugins/user/joomla/src/Extension/Joomla.php
index d9dd5cccc01c6..1b6d144bfecf4 100644
--- a/plugins/user/joomla/src/Extension/Joomla.php
+++ b/plugins/user/joomla/src/Extension/Joomla.php
@@ -11,6 +11,12 @@
 namespace Joomla\Plugin\User\Joomla\Extension;
 
 use Joomla\CMS\Component\ComponentHelper;
+use Joomla\CMS\Event\Model\PrepareFormEvent;
+use Joomla\CMS\Event\User\AfterDeleteEvent;
+use Joomla\CMS\Event\User\AfterLoginEvent;
+use Joomla\CMS\Event\User\AfterSaveEvent;
+use Joomla\CMS\Event\User\LoginEvent;
+use Joomla\CMS\Event\User\LogoutEvent;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Language\LanguageFactoryInterface;
 use Joomla\CMS\Log\Log;
@@ -23,6 +29,7 @@
 use Joomla\Database\DatabaseAwareTrait;
 use Joomla\Database\Exception\ExecutionFailureException;
 use Joomla\Database\ParameterType;
+use Joomla\Event\SubscriberInterface;
 use Joomla\Registry\Registry;
 
 // phpcs:disable PSR1.Files.SideEffects
@@ -34,23 +41,44 @@
  *
  * @since  1.5
  */
-final class Joomla extends CMSPlugin
+final class Joomla extends CMSPlugin implements SubscriberInterface
 {
     use DatabaseAwareTrait;
     use UserFactoryAwareTrait;
 
+    /**
+     * Returns an array of events this subscriber will listen to.
+     *
+     * @return array
+     *
+     * @since   __DEPLOY_VERSION__
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onContentPrepareForm' => 'onContentPrepareForm',
+            'onUserAfterDelete'    => 'onUserAfterDelete',
+            'onUserAfterSave'      => 'onUserAfterSave',
+            'onUserLogin'          => 'onUserLogin',
+            'onUserLogout'         => 'onUserLogout',
+            'onUserAfterLogin'     => 'onUserAfterLogin',
+        ];
+    }
+
     /**
      * Set as required the passwords fields when mail to user is set to No
      *
-     * @param   \Joomla\CMS\Form\Form  $form  The form to be altered.
-     * @param   mixed                  $data  The associated data for the form.
+     * @param   PrepareFormEvent $event  The event instance.
      *
-     * @return  boolean
+     * @return  void
      *
      * @since   4.0.0
      */
-    public function onContentPrepareForm($form, $data)
+    public function onContentPrepareForm(PrepareFormEvent $event)
     {
+        $form = $event->getForm();
+        $data = $event->getData();
+
         // Check we are manipulating a valid user form before modifying it.
         $name = $form->getName();
 
@@ -71,8 +99,6 @@ public function onContentPrepareForm($form, $data)
                 $form->setFieldAttribute('password2', 'required', 'true');
             }
         }
-
-        return true;
     }
 
     /**
@@ -80,16 +106,17 @@ public function onContentPrepareForm($form, $data)
      *
      * Method is called after user data is deleted from the database
      *
-     * @param   array    $user     Holds the user data
-     * @param   boolean  $success  True if user was successfully stored in the database
-     * @param   string   $msg      Message
+     * @param   AfterDeleteEvent $event  The event instance.
      *
      * @return  void
      *
      * @since   1.6
      */
-    public function onUserAfterDelete($user, $success, $msg): void
+    public function onUserAfterDelete(AfterDeleteEvent $event): void
     {
+        $user    = $event->getUser();
+        $success = $event->getDeletingResult();
+
         if (!$success) {
             return;
         }
@@ -147,17 +174,17 @@ public function onUserAfterDelete($user, $success, $msg): void
      *
      * This method sends a registration email to new users created in the backend.
      *
-     * @param   array    $user     Holds the new user data.
-     * @param   boolean  $isnew    True if a new user is stored.
-     * @param   boolean  $success  True if user was successfully stored in the database.
-     * @param   string   $msg      Message.
+     * @param   AfterSaveEvent $event  The event instance.
      *
      * @return  void
      *
      * @since   1.6
      */
-    public function onUserAfterSave($user, $isnew, $success, $msg): void
+    public function onUserAfterSave(AfterSaveEvent $event): void
     {
+        $user  = $event->getUser();
+        $isnew = $event->getIsNew();
+
         $mail_to_user = $this->params->get('mail_to_user', 1);
 
         if (!$isnew || !$mail_to_user) {
@@ -249,27 +276,30 @@ public function onUserAfterSave($user, $isnew, $success, $msg): void
     /**
      * This method should handle any login logic and report back to the subject
      *
-     * @param   array  $user     Holds the user data
-     * @param   array  $options  Array holding options (remember, autoregister, group)
+     * @param   LoginEvent $event  The event instance.
      *
-     * @return  boolean  True on success
+     * @return  void
      *
      * @since   1.5
      */
-    public function onUserLogin($user, $options = [])
+    public function onUserLogin(LoginEvent $event)
     {
+        $user     = $event->getAuthenticationResponse();
+        $options  = $event->getOptions();
         $instance = $this->getUser($user, $options);
 
         // If getUser returned an error, then pass it back.
         if ($instance instanceof \Exception) {
-            return false;
+            $event->addResult(false);
+            return;
         }
 
         // If the user is blocked, redirect with an error
         if ($instance->block == 1) {
             $this->getApplication()->enqueueMessage($this->getApplication()->getLanguage()->_('JERROR_NOLOGIN_BLOCKED'), 'warning');
+            $event->addResult(false);
 
-            return false;
+            return;
         }
 
         // Authorise the user based on the group information
@@ -282,8 +312,9 @@ public function onUserLogin($user, $options = [])
 
         if (!$result) {
             $this->getApplication()->enqueueMessage($this->getApplication()->getLanguage()->_('JERROR_LOGIN_DENIED'), 'warning');
+            $event->addResult(false);
 
-            return false;
+            return;
         }
 
         // Mark the user as logged in
@@ -337,22 +368,22 @@ public function onUserLogin($user, $options = [])
                 true
             );
         }
-
-        return true;
     }
 
     /**
      * This method should handle any logout logic and report back to the subject
      *
-     * @param   array  $user     Holds the user data.
-     * @param   array  $options  Array holding options (client, ...).
+     * @param   LogoutEvent $event  The event instance.
      *
-     * @return  boolean  True on success
+     * @return  void
      *
      * @since   1.5
      */
-    public function onUserLogout($user, $options = [])
+    public function onUserLogout(LogoutEvent $event)
     {
+        $user     = $event->getParameters();
+        $options  = $event->getOptions();
+
         $my      = $this->getApplication()->getIdentity();
         $session = Factory::getSession();
 
@@ -360,7 +391,7 @@ public function onUserLogout($user, $options = [])
 
         // Make sure we're a valid user first
         if ($user['id'] === 0 && !$my->get('tmp_user')) {
-            return true;
+            return;
         }
 
         $sharedSessions = $this->getApplication()->get('shared_session', '0');
@@ -386,8 +417,6 @@ public function onUserLogout($user, $options = [])
         if ($this->getApplication()->isClient('site')) {
             $this->getApplication()->getInput()->cookie->set('joomla_user_state', '', 1, $this->getApplication()->get('cookie_path', '/'), $this->getApplication()->get('cookie_domain', ''));
         }
-
-        return true;
     }
 
     /**
@@ -399,18 +428,18 @@ public function onUserLogout($user, $options = [])
      * logging in, something which would cause the Captive page to appear in the frontend and redirect you to the public
      * frontend homepage after successfully passing the Two Step verification process.
      *
-     * @param   array  $options  Passed by Joomla. user: a User object; responseType: string, authentication response type.
+     * @param   AfterLoginEvent $event  The event instance.
      *
      * @return void
      * @since  4.2.0
      */
-    public function onUserAfterLogin(array $options): void
+    public function onUserAfterLogin(AfterLoginEvent $event): void
     {
         if (!($this->getApplication()->isClient('administrator')) && !($this->getApplication()->isClient('site'))) {
             return;
         }
 
-        $this->disableMfaOnSilentLogin($options);
+        $this->disableMfaOnSilentLogin($event->getOptions());
     }
 
     /**
diff --git a/plugins/user/profile/src/Extension/Profile.php b/plugins/user/profile/src/Extension/Profile.php
index 9f68cf0b4defd..75b79cfdc2dae 100644
--- a/plugins/user/profile/src/Extension/Profile.php
+++ b/plugins/user/profile/src/Extension/Profile.php
@@ -11,7 +11,11 @@
 namespace Joomla\Plugin\User\Profile\Extension;
 
 use Joomla\CMS\Date\Date;
-use Joomla\CMS\Form\Form;
+use Joomla\CMS\Event\Model\PrepareDataEvent;
+use Joomla\CMS\Event\Model\PrepareFormEvent;
+use Joomla\CMS\Event\User\AfterDeleteEvent;
+use Joomla\CMS\Event\User\AfterSaveEvent;
+use Joomla\CMS\Event\User\BeforeSaveEvent;
 use Joomla\CMS\Form\FormHelper;
 use Joomla\CMS\HTML\HTMLHelper;
 use Joomla\CMS\Language\Text;
@@ -19,6 +23,7 @@
 use Joomla\CMS\String\PunycodeHelper;
 use Joomla\Database\DatabaseAwareTrait;
 use Joomla\Database\ParameterType;
+use Joomla\Event\SubscriberInterface;
 use Joomla\Utilities\ArrayHelper;
 
 // phpcs:disable PSR1.Files.SideEffects
@@ -30,7 +35,7 @@
  *
  * @since  1.6
  */
-final class Profile extends CMSPlugin
+final class Profile extends CMSPlugin implements SubscriberInterface
 {
     use DatabaseAwareTrait;
 
@@ -43,21 +48,41 @@ final class Profile extends CMSPlugin
      */
     private $date = '';
 
+    /**
+     * Returns an array of events this subscriber will listen to.
+     *
+     * @return array
+     *
+     * @since   __DEPLOY_VERSION__
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onContentPrepareData' => 'onContentPrepareData',
+            'onContentPrepareForm' => 'onContentPrepareForm',
+            'onUserBeforeSave'     => 'onUserBeforeSave',
+            'onUserAfterSave'      => 'onUserAfterSave',
+            'onUserAfterDelete'    => 'onUserAfterDelete',
+        ];
+    }
+
     /**
      * Runs on content preparation
      *
-     * @param   string  $context  The context for the data
-     * @param   object  $data     An object containing the data for the form.
+     * @param   PrepareDataEvent $event  The event instance.
      *
-     * @return  boolean
+     * @return  void
      *
      * @since   1.6
      */
-    public function onContentPrepareData($context, $data)
+    public function onContentPrepareData(PrepareDataEvent $event)
     {
+        $context = $event->getContext();
+        $data    = $event->getData();
+
         // Check we are manipulating a valid form.
         if (!\in_array($context, ['com_users.profile', 'com_users.user', 'com_users.registration'])) {
-            return true;
+            return;
         }
 
         // Load plugin language files
@@ -114,8 +139,6 @@ public function onContentPrepareData($context, $data)
                 HTMLHelper::register('users.dob', [__CLASS__, 'dob']);
             }
         }
-
-        return true;
     }
 
     /**
@@ -192,20 +215,20 @@ public static function tos($value)
     /**
      * Adds additional fields to the user editing form
      *
-     * @param   Form   $form  The form to be altered.
-     * @param   mixed  $data  The associated data for the form.
+     * @param   PrepareFormEvent $event  The event instance.
      *
-     * @return  boolean
+     * @return  void
      *
      * @since   1.6
      */
-    public function onContentPrepareForm(Form $form, $data)
+    public function onContentPrepareForm(PrepareFormEvent $event)
     {
+        $form = $event->getForm();
         // Check we are manipulating a valid form.
         $name = $form->getName();
 
         if (!\in_array($name, ['com_users.user', 'com_users.profile', 'com_users.registration'])) {
-            return true;
+            return;
         }
 
         // Load plugin language files
@@ -281,24 +304,22 @@ public function onContentPrepareForm(Form $form, $data)
         if (!\count($remainingfields)) {
             $form->removeGroup('profile');
         }
-
-        return true;
     }
 
     /**
      * Method is called before user data is stored in the database
      *
-     * @param   array    $user   Holds the old user data.
-     * @param   boolean  $isnew  True if a new user is stored.
-     * @param   array    $data   Holds the new user data.
+     * @param   BeforeSaveEvent $event  The event instance.
      *
-     * @return  boolean
+     * @return  void
      *
      * @since   3.1
      * @throws  \InvalidArgumentException on invalid date.
      */
-    public function onUserBeforeSave($user, $isnew, $data)
+    public function onUserBeforeSave(BeforeSaveEvent $event)
     {
+        $data = $event->getData();
+
         // Load plugin language files
         $this->loadLanguage();
 
@@ -327,22 +348,19 @@ public function onUserBeforeSave($user, $isnew, $data)
         if ($task === 'register' && $tosEnabled && $option === 'com_users' && !$data['profile']['tos']) {
             throw new \InvalidArgumentException($this->getApplication()->getLanguage()->_('PLG_USER_PROFILE_FIELD_TOS_DESC_SITE'));
         }
-
-        return true;
     }
 
     /**
      * Saves user profile data
      *
-     * @param   array    $data    entered user data
-     * @param   boolean  $isNew   true if this is a new user
-     * @param   boolean  $result  true if saving the user worked
-     * @param   string   $error   error message
+     * @param   AfterSaveEvent $event  The event instance.
      *
      * @return  void
      */
-    public function onUserAfterSave($data, $isNew, $result, $error): void
+    public function onUserAfterSave(AfterSaveEvent $event): void
     {
+        $data   = $event->getUser();
+        $result = $event->getSavingResult();
         $userId = ArrayHelper::getValue($data, 'id', 0, 'int');
 
         if ($userId && $result && isset($data['profile']) && \count($data['profile'])) {
@@ -415,14 +433,15 @@ public function onUserAfterSave($data, $isNew, $result, $error): void
      *
      * Method is called after user data is deleted from the database
      *
-     * @param   array    $user     Holds the user data
-     * @param   boolean  $success  True if user was successfully stored in the database
-     * @param   string   $msg      Message
+     * @param   AfterDeleteEvent $event  The event instance.
      *
      * @return  void
      */
-    public function onUserAfterDelete($user, $success, $msg): void
+    public function onUserAfterDelete(AfterDeleteEvent $event): void
     {
+        $user    = $event->getUser();
+        $success = $event->getDeletingResult();
+
         if (!$success) {
             return;
         }
diff --git a/plugins/user/terms/src/Extension/Terms.php b/plugins/user/terms/src/Extension/Terms.php
index 98b7f8ea280ec..0995d2a8093f0 100644
--- a/plugins/user/terms/src/Extension/Terms.php
+++ b/plugins/user/terms/src/Extension/Terms.php
@@ -10,10 +10,13 @@
 
 namespace Joomla\Plugin\User\Terms\Extension;
 
-use Joomla\CMS\Form\Form;
+use Joomla\CMS\Event\Model\PrepareFormEvent;
+use Joomla\CMS\Event\User\AfterSaveEvent;
+use Joomla\CMS\Event\User\BeforeSaveEvent;
 use Joomla\CMS\Form\FormHelper;
 use Joomla\CMS\Plugin\CMSPlugin;
 use Joomla\Component\Actionlogs\Administrator\Model\ActionlogModel;
+use Joomla\Event\SubscriberInterface;
 use Joomla\Utilities\ArrayHelper;
 
 // phpcs:disable PSR1.Files.SideEffects
@@ -25,25 +28,42 @@
  *
  * @since  3.9.0
  */
-final class Terms extends CMSPlugin
+final class Terms extends CMSPlugin implements SubscriberInterface
 {
+    /**
+     * Returns an array of events this subscriber will listen to.
+     *
+     * @return array
+     *
+     * @since   __DEPLOY_VERSION__
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onContentPrepareForm' => 'onContentPrepareForm',
+            'onUserBeforeSave'     => 'onUserBeforeSave',
+            'onUserAfterSave'      => 'onUserAfterSave',
+        ];
+    }
+
     /**
      * Adds additional fields to the user registration form
      *
-     * @param   Form   $form  The form to be altered.
-     * @param   mixed  $data  The associated data for the form.
+     * @param   PrepareFormEvent $event  The event instance.
      *
-     * @return  boolean
+     * @return  void
      *
      * @since   3.9.0
      */
-    public function onContentPrepareForm(Form $form, $data)
+    public function onContentPrepareForm(PrepareFormEvent $event)
     {
+        $form = $event->getForm();
+
         // Check we are manipulating a valid form - we only display this on user registration form.
         $name = $form->getName();
 
         if (!\in_array($name, ['com_users.registration'])) {
-            return true;
+            return;
         }
 
         // Load plugin language files
@@ -67,27 +87,27 @@ public function onContentPrepareForm(Form $form, $data)
     /**
      * Method is called before user data is stored in the database
      *
-     * @param   array    $user   Holds the old user data.
-     * @param   boolean  $isNew  True if a new user is stored.
-     * @param   array    $data   Holds the new user data.
+     * @param   BeforeSaveEvent $event  The event instance.
      *
-     * @return  boolean
+     * @return  void
      *
      * @since   3.9.0
      * @throws  \InvalidArgumentException on missing required data.
      */
-    public function onUserBeforeSave($user, $isNew, $data)
+    public function onUserBeforeSave(BeforeSaveEvent $event)
     {
+        $user = $event->getUser();
+
         // // Only check for front-end user registration
         if ($this->getApplication()->isClient('administrator')) {
-            return true;
+            return;
         }
 
         $userId = ArrayHelper::getValue($user, 'id', 0, 'int');
 
         // User already registered, no need to check it further
         if ($userId > 0) {
-            return true;
+            return;
         }
 
         // Load plugin language files
@@ -102,24 +122,23 @@ public function onUserBeforeSave($user, $isNew, $data)
         if ($option == 'com_users' && \in_array($task, ['registration.register']) && empty($form['terms']['terms'])) {
             throw new \InvalidArgumentException($this->getApplication()->getLanguage()->_('PLG_USER_TERMS_FIELD_ERROR'));
         }
-
-        return true;
     }
 
     /**
      * Saves user profile data
      *
-     * @param   array    $data    entered user data
-     * @param   boolean  $isNew   true if this is a new user
-     * @param   boolean  $result  true if saving the user worked
-     * @param   string   $error   error message
+     * @param   AfterSaveEvent $event  The event instance.
      *
      * @return  void
      *
      * @since   3.9.0
      */
-    public function onUserAfterSave($data, $isNew, $result, $error): void
+    public function onUserAfterSave(AfterSaveEvent $event): void
     {
+        $data   = $event->getUser();
+        $isNew  = $event->getIsNew();
+        $result = $event->getSavingResult();
+
         if (!$isNew || !$result) {
             return;
         }
diff --git a/plugins/user/token/src/Extension/Token.php b/plugins/user/token/src/Extension/Token.php
index 3bd8a06dff386..b04a2e8262ea8 100644
--- a/plugins/user/token/src/Extension/Token.php
+++ b/plugins/user/token/src/Extension/Token.php
@@ -11,12 +11,17 @@
 namespace Joomla\Plugin\User\Token\Extension;
 
 use Joomla\CMS\Crypt\Crypt;
+use Joomla\CMS\Event\Model\PrepareDataEvent;
+use Joomla\CMS\Event\Model\PrepareFormEvent;
+use Joomla\CMS\Event\User\AfterDeleteEvent;
+use Joomla\CMS\Event\User\AfterSaveEvent;
 use Joomla\CMS\Form\Form;
 use Joomla\CMS\Plugin\CMSPlugin;
 use Joomla\CMS\Plugin\PluginHelper;
 use Joomla\CMS\User\UserFactoryAwareTrait;
 use Joomla\Database\DatabaseAwareTrait;
 use Joomla\Database\ParameterType;
+use Joomla\Event\SubscriberInterface;
 use Joomla\Utilities\ArrayHelper;
 
 // phpcs:disable PSR1.Files.SideEffects
@@ -28,7 +33,7 @@
  *
  * @since  3.9.0
  */
-final class Token extends CMSPlugin
+final class Token extends CMSPlugin implements SubscriberInterface
 {
     use DatabaseAwareTrait;
     use UserFactoryAwareTrait;
@@ -60,37 +65,56 @@ final class Token extends CMSPlugin
      */
     private $tokenLength = 32;
 
+    /**
+     * Returns an array of events this subscriber will listen to.
+     *
+     * @return array
+     *
+     * @since   __DEPLOY_VERSION__
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onContentPrepareData' => 'onContentPrepareData',
+            'onContentPrepareForm' => 'onContentPrepareForm',
+            'onUserAfterSave'      => 'onUserAfterSave',
+            'onUserAfterDelete'    => 'onUserAfterDelete',
+        ];
+    }
+
     /**
      * Inject the Joomla token management panel's data into the User Profile.
      *
      * This method is called whenever Joomla is preparing the data for an XML form for display.
      *
-     * @param   string  $context  Form context, passed by Joomla
-     * @param   mixed   $data     Form data
+     * @param   PrepareDataEvent $event  The event instance.
      *
-     * @return  boolean
+     * @return  void
      * @since   4.0.0
      */
-    public function onContentPrepareData(string $context, &$data): bool
+    public function onContentPrepareData(PrepareDataEvent $event): void
     {
         // Only do something if the api-authentication plugin with the same name is published
         if (!PluginHelper::isEnabled('api-authentication', $this->_name)) {
-            return true;
+            return;
         }
 
+        $context = $event->getContext();
+        $data    = $event->getData();
+
         // Check we are manipulating a valid form.
         if (!\in_array($context, $this->allowedContexts)) {
-            return true;
+            return;
         }
 
         // $data must be an object
         if (!\is_object($data)) {
-            return true;
+            return;
         }
 
         // We expect the numeric user ID in $data->id
         if (!isset($data->id)) {
-            return true;
+            return;
         }
 
         // Get the user ID
@@ -98,11 +122,11 @@ public function onContentPrepareData(string $context, &$data): bool
 
         // Make sure we have a positive integer user ID
         if ($userId <= 0) {
-            return true;
+            return;
         }
 
         if (!$this->isInAllowedUserGroup($userId)) {
-            return true;
+            return;
         }
 
         // Load plugin language files
@@ -162,31 +186,31 @@ public function onContentPrepareData(string $context, &$data): bool
 
             $data->{$this->profileKeyPrefix} = $pluginData;
         }
-
-        return true;
     }
 
     /**
      * Runs whenever Joomla is preparing a form object.
      *
-     * @param   Form   $form  The form to be altered.
-     * @param   mixed  $data  The associated data for the form.
+     * @param   PrepareFormEvent $event  The event instance.
      *
-     * @return  boolean
+     * @return  void
      *
      * @throws  \Exception  When $form is not a valid form object
      * @since   4.0.0
      */
-    public function onContentPrepareForm(Form $form, $data): bool
+    public function onContentPrepareForm(PrepareFormEvent $event): void
     {
         // Only do something if the api-authentication plugin with the same name is published
         if (!PluginHelper::isEnabled('api-authentication', $this->_name)) {
-            return true;
+            return;
         }
 
+        $form = $event->getForm();
+        $data = $event->getData();
+
         // Check we are manipulating a valid form.
         if (!\in_array($form->getName(), $this->allowedContexts)) {
-            return true;
+            return;
         }
 
         // If we are on the save command, no data is passed to $data variable, we need to get it directly from request
@@ -204,7 +228,7 @@ public function onContentPrepareForm(Form $form, $data): bool
         $userId = (\is_object($data) && isset($data->id)) ? $data->id : 0;
 
         if (!empty($userId) && !$this->isInAllowedUserGroup($userId)) {
-            return true;
+            return;
         }
 
         // Load plugin language files
@@ -243,23 +267,22 @@ public function onContentPrepareForm(Form $form, $data): bool
         if (($form->getName() === 'com_users.profile') && ($this->getApplication()->getInput()->get('layout') !== 'edit')) {
             $form->removeField('reset', 'joomlatoken');
         }
-
-        return true;
     }
 
     /**
      * Save the Joomla token in the user profile field
      *
-     * @param   mixed    $data    The incoming form data
-     * @param   bool     $isNew   Is this a new user?
-     * @param   bool     $result  Has Joomla successfully saved the user?
-     * @param   ?string  $error   Error string
+     * @param   AfterSaveEvent $event  The event instance.
      *
      * @return  void
      * @since   4.0.0
      */
-    public function onUserAfterSave($data, bool $isNew, bool $result, ?string $error): void
+    public function onUserAfterSave(AfterSaveEvent $event): void
     {
+        $data   = $event->getUser();
+        $isNew  = $event->getIsNew();
+        $result = $event->getSavingResult();
+
         if (!\is_array($data)) {
             return;
         }
@@ -371,17 +394,18 @@ public function onUserAfterSave($data, bool $isNew, bool $result, ?string $error
      *
      * This event is called after the user data is deleted from the database.
      *
-     * @param   array    $user     Holds the user data
-     * @param   boolean  $success  True if user was successfully stored in the database
-     * @param   string   $msg      Message
+     * @param   AfterDeleteEvent $event  The event instance.
      *
      * @return  void
      *
      * @throws  \Exception
      * @since   4.0.0
      */
-    public function onUserAfterDelete(array $user, bool $success, string $msg): void
+    public function onUserAfterDelete(AfterDeleteEvent $event): void
     {
+        $user    = $event->getUser();
+        $success = $event->getDeletingResult();
+
         if (!$success) {
             return;
         }