diff --git a/libraries/src/Button/TransitionButton.php b/libraries/src/Button/TransitionButton.php
index 719b519373243..b8279c0d3d45f 100644
--- a/libraries/src/Button/TransitionButton.php
+++ b/libraries/src/Button/TransitionButton.php
@@ -51,8 +51,6 @@ public function __construct(array $options = [])
 	 * @param   integer|null  $value        Current value of this item.
 	 * @param   integer|null  $row          The row number of this item.
 	 * @param   array         $options      The options to override group options.
-	 * @param   string|Date   $publishUp    The date which item publish up.
-	 * @param   string|Date   $publishDown  The date which item publish down.
 	 *
 	 * @return  string  Rendered HTML.
 	 *
diff --git a/libraries/src/Event/View/DisplayEvent.php b/libraries/src/Event/View/DisplayEvent.php
index 46a6f2c3e4e5f..325db2938d924 100644
--- a/libraries/src/Event/View/DisplayEvent.php
+++ b/libraries/src/Event/View/DisplayEvent.php
@@ -33,14 +33,24 @@ class DisplayEvent extends AbstractImmutableEvent
 	 */
 	public function __construct($name, array $arguments = array())
 	{
-		if (!isset($arguments['subject']) || !($arguments['subject'] instanceof ViewInterface))
+		if (!isset($arguments['subject']))
 		{
-			throw new BadMethodCallException("Argument 'subject' of event {$this->name} is required but has not been provided or is not of type 'ViewInterface'");
+			throw new BadMethodCallException("Argument 'subject' of event {$this->name} is required but has not been provided");
+		}
+
+		if (!($arguments['subject'] instanceof ViewInterface))
+		{
+			throw new BadMethodCallException("Argument 'subject' of event {$this->name} is not of type 'ViewInterface'");
+		}
+
+		if (!isset($arguments['extension']))
+		{
+			throw new BadMethodCallException("Argument 'extension' of event {$this->name} is required but has not been provided");
 		}
 
 		if (!isset($arguments['extension']) || !is_string($arguments['extension']))
 		{
-			throw new BadMethodCallException("Argument 'extension' of event {$this->name} is required but has not been provided or is not of type 'string'");
+			throw new BadMethodCallException("Argument 'extension' of event {$this->name} is not of type 'string'");
 		}
 
 		if (strpos($arguments['extension'], '.') === false)
diff --git a/libraries/src/Event/Workflow/WorkflowFunctionalityUsedEvent.php b/libraries/src/Event/Workflow/WorkflowFunctionalityUsedEvent.php
index fb0b10af1e4a3..afb5938681b09 100644
--- a/libraries/src/Event/Workflow/WorkflowFunctionalityUsedEvent.php
+++ b/libraries/src/Event/Workflow/WorkflowFunctionalityUsedEvent.php
@@ -41,7 +41,11 @@ public function __construct($name, array $arguments = array())
 	/**
 	 * Set used parameter to true
 	 *
-	 * @since   1.0
+	 * @param   bool  $value  The value to set
+	 *
+	 * @return void
+	 *
+	 * @since   4.0.0
 	 */
 	public function setUsed($value = true)
 	{
diff --git a/libraries/src/Event/Workflow/WorkflowTransitionEvent.php b/libraries/src/Event/Workflow/WorkflowTransitionEvent.php
index 0b64831b916b9..58c68150abd4f 100644
--- a/libraries/src/Event/Workflow/WorkflowTransitionEvent.php
+++ b/libraries/src/Event/Workflow/WorkflowTransitionEvent.php
@@ -41,7 +41,11 @@ public function __construct($name, array $arguments = array())
 	/**
 	 * Set used parameter to true
 	 *
-	 * @since   1.0
+	 * @param   bool  $value  The value to set
+	 *
+	 * @return void
+	 *
+	 * @since   4.0.0
 	 */
 	public function setStopTransition($value = true)
 	{
diff --git a/libraries/src/Workflow/Workflow.php b/libraries/src/Workflow/Workflow.php
index 4aee23adbf582..5516c6d8d8ad2 100644
--- a/libraries/src/Workflow/Workflow.php
+++ b/libraries/src/Workflow/Workflow.php
@@ -178,11 +178,11 @@ public function executeTransition(array $pks, int $transition_id): bool
 				$db->quoteName('t.workflow_id'),
 			]
 		)
-		      ->from($db->quoteName('#__workflow_transitions', 't'))
-		      ->join('LEFT', $db->quoteName('#__workflow_stages', 's'), $db->quoteName('s.id') . ' = ' . $db->quoteName('t.to_stage_id'))
-		      ->where($db->quoteName('t.id') . ' = :id')
-		      ->where($db->quoteName('t.published') . ' = 1')
-		      ->bind(':id', $transition_id, ParameterType::INTEGER);
+			->from($db->quoteName('#__workflow_transitions', 't'))
+			->join('LEFT', $db->quoteName('#__workflow_stages', 's'), $db->quoteName('s.id') . ' = ' . $db->quoteName('t.to_stage_id'))
+			->where($db->quoteName('t.id') . ' = :id')
+			->where($db->quoteName('t.published') . ' = 1')
+			->bind(':id', $transition_id, ParameterType::INTEGER);
 
 		$transition = $db->setQuery($query)->loadObject();
 
@@ -202,7 +202,8 @@ public function executeTransition(array $pks, int $transition_id): bool
 			if (!\in_array($transition->from_stage_id, [
 					$assoc->stage_id,
 					-1
-				]) || $transition->workflow_id !== $assoc->workflow_id)
+				]
+			) || $transition->workflow_id !== $assoc->workflow_id)
 			{
 				return false;
 			}
@@ -272,17 +273,17 @@ public function createAssociation(int $pk, int $state): bool
 			$query = $db->getQuery(true);
 
 			$query->insert($db->quoteName('#__workflow_associations'))
-			      ->columns(
-				      [
-					      $db->quoteName('item_id'),
-					      $db->quoteName('stage_id'),
-					      $db->quoteName('extension'),
-				      ]
-			      )
-			      ->values(':pk, :state, :extension')
-			      ->bind(':pk', $pk, ParameterType::INTEGER)
-			      ->bind(':state', $state, ParameterType::INTEGER)
-			      ->bind(':extension', $this->extension);
+				->columns(
+					[
+						$db->quoteName('item_id'),
+						$db->quoteName('stage_id'),
+						$db->quoteName('extension'),
+					]
+				)
+				->values(':pk, :state, :extension')
+				->bind(':pk', $pk, ParameterType::INTEGER)
+				->bind(':state', $state, ParameterType::INTEGER)
+				->bind(':extension', $this->extension);
 
 			$db->setQuery($query)->execute();
 		}
@@ -314,11 +315,11 @@ public function updateAssociations(array $pks, int $state): bool
 			$query = $db->getQuery(true);
 
 			$query->update($db->quoteName('#__workflow_associations'))
-			      ->set($db->quoteName('stage_id') . ' = :state')
-			      ->whereIn($db->quoteName('item_id'), $pks)
-			      ->where($db->quoteName('extension') . ' = :extension')
-			      ->bind(':state', $state, ParameterType::INTEGER)
-			      ->bind(':extension', $this->extension);
+				->set($db->quoteName('stage_id') . ' = :state')
+				->whereIn($db->quoteName('item_id'), $pks)
+				->where($db->quoteName('extension') . ' = :extension')
+				->bind(':state', $state, ParameterType::INTEGER)
+				->bind(':extension', $this->extension);
 
 			$db->setQuery($query)->execute();
 		}
@@ -385,19 +386,19 @@ public function getAssociation(int $item_id): ?\stdClass
 				$db->quoteName('s.workflow_id'),
 			]
 		)
-		      ->from($db->quoteName('#__workflow_associations', 'a'))
-		      ->innerJoin(
-			      $db->quoteName('#__workflow_stages', 's'),
-			      $db->quoteName('a.stage_id') . ' = ' . $db->quoteName('s.id')
-		      )
-		      ->where(
-			      [
-				      $db->quoteName('item_id') . ' = :id',
-				      $db->quoteName('extension') . ' = :extension',
-			      ]
-		      )
-		      ->bind(':id', $item_id, ParameterType::INTEGER)
-		      ->bind(':extension', $this->extension);
+			->from($db->quoteName('#__workflow_associations', 'a'))
+			->innerJoin(
+				$db->quoteName('#__workflow_stages', 's'),
+				$db->quoteName('a.stage_id') . ' = ' . $db->quoteName('s.id')
+			)
+			->where(
+				[
+					  $db->quoteName('item_id') . ' = :id',
+					  $db->quoteName('extension') . ' = :extension',
+				  ]
+			)
+			->bind(':id', $item_id, ParameterType::INTEGER)
+			->bind(':extension', $this->extension);
 
 		return $db->setQuery($query)->loadObject();
 	}
diff --git a/libraries/src/Workflow/WorkflowPluginTrait.php b/libraries/src/Workflow/WorkflowPluginTrait.php
index c9efe14a80d0f..ec676df7b9333 100644
--- a/libraries/src/Workflow/WorkflowPluginTrait.php
+++ b/libraries/src/Workflow/WorkflowPluginTrait.php
@@ -24,8 +24,8 @@ trait WorkflowPluginTrait
 	/**
 	 * Add different parameter options to the transition view, we need when executing the transition
 	 *
-	 * @param Form      $form The form
-	 * @param \stdClass $data The data
+	 * @param   Form      $form The form
+	 * @param   \stdClass $data The data
 	 *
 	 * @return  boolean
 	 *
@@ -56,7 +56,7 @@ protected function enhanceWorkflowTransitionForm(Form $form, $data)
 	/**
 	 * Get the workflow for a given ID
 	 *
-	 * @param int|null $workflow_id ID of the workflow
+	 * @param   int|null $workflow_id ID of the workflow
 	 *
 	 * @return  CMSObject|boolean  Object on success, false on failure.
 	 *
@@ -72,15 +72,15 @@ protected function getWorkflow(int $workflow_id = null)
 		}
 
 		return $this->app->bootComponent('com_workflow')
-										 ->getMVCFactory()
-										 ->createModel('Workflow', 'Administrator', ['ignore_request' => true])
-										 ->getItem($workflow_id);
+			->getMVCFactory()
+			->createModel('Workflow', 'Administrator', ['ignore_request' => true])
+			->getItem($workflow_id);
 	}
 
 	/**
 	 * Check if the current plugin should execute workflow related activities
 	 *
-	 * @param string $context Context to check
+	 * @param   string $context Context to check
 	 *
 	 * @return boolean
 	 *
@@ -94,9 +94,9 @@ protected function isSupported($context)
 	/**
 	 * Check if the context is listed in the whitelist or in the blacklist and return the result
 	 *
-	 * @param string $context Context to check
+	 * @param   string $context Context to check
 	 *
-	 * @return bool
+	 * @return boolean
 	 */
 	protected function checkWhiteAndBlacklist($context)
 	{
@@ -133,15 +133,17 @@ protected function checkWhiteAndBlacklist($context)
 	/**
 	 * Check if the context is listed in the whitelist or in the blacklist and return the result
 	 *
-	 * @param string $context Context to check
+	 * @param   string  $context       Context to check
+	 * @param   string  $functionality The funcationality
 	 *
-	 * @return bool
+	 * @return boolean
 	 */
 	protected function checkExtensionSupport($context, $functionality)
 	{
 		$parts = explode('.', $context);
 
 		$component = $this->app->bootComponent($parts[0]);
+
 		if (!$component instanceof WorkflowServiceInterface
 			|| !$component->isWorkflowActive($context)
 			|| !$component->isFunctionalityActive($functionality, $context))
diff --git a/libraries/src/Workflow/WorkflowServiceTrait.php b/libraries/src/Workflow/WorkflowServiceTrait.php
index dae9cb5cce884..6e8760c20faa0 100644
--- a/libraries/src/Workflow/WorkflowServiceTrait.php
+++ b/libraries/src/Workflow/WorkflowServiceTrait.php
@@ -69,22 +69,22 @@ public function supportFunctionality($functionality, $context): bool
 	/**
 	 * Check if the functionality is activated in the component configuration
 	 *
-	 * @param string $functionality
-	 * @param string $extension
+	 * @param   string  $functionality  The functionality
+	 * @param   string  $extension      The extension
 	 *
-	 * @return bool
+	 * @return boolean
 	 * @throws \Exception
 	 *
 	 * @since   4.0.0
 	 */
-	public function isFunctionalityActive($functionality, $context): bool
+	public function isFunctionalityActive($functionality, $extension): bool
 	{
-		if (!$this->isWorkflowActive($context))
+		if (!$this->isWorkflowActive($extension))
 		{
 			return false;
 		}
 
-		$parts  = explode('.', $context);
+		$parts  = explode('.', $extension);
 		$config = ComponentHelper::getParams($parts[0]);
 		$option = 'workflow_functionality_' . str_replace('.', '_', $functionality);
 
@@ -99,10 +99,10 @@ public function isFunctionalityActive($functionality, $context): bool
 	/**
 	 * Check if the functionality is used by a plugin
 	 *
-	 * @param string $functionality
-	 * @param string $extension
+	 * @param   string  $functionality  The functionality
+	 * @param   string  $extension      The extension
 	 *
-	 * @return bool
+	 * @return boolean
 	 * @throws \Exception
 	 *
 	 * @since   4.0.0
diff --git a/plugins/workflow/featuring/featuring.php b/plugins/workflow/featuring/featuring.php
index faf8a4be436f5..88c9fd675b2ba 100644
--- a/plugins/workflow/featuring/featuring.php
+++ b/plugins/workflow/featuring/featuring.php
@@ -132,7 +132,7 @@ protected function enhanceItemForm(Form $form, $data)
 		$modelName = $component->getModelName($context);
 
 		$table = $component->getMVCFactory()->createModel($modelName, $this->app->getName(), ['ignore_request' => true])
-											 ->getTable();
+			->getTable();
 
 		$fieldname = $table->getColumnAlias('featured');
 
@@ -278,7 +278,8 @@ public function onWorkflowBeforeTransition(WorkflowTransitionEvent $event)
 			$context,
 			$pks,
 			$value
-		]);
+			]
+		);
 
 		// Release whitelist, the job is done
 		$this->app->set('plgWorkflowFeaturing.' . $context, []);
@@ -376,7 +377,9 @@ public function onContentBeforeChangeFeatured(EventInterface $event)
 	public function onContentBeforeSave(EventInterface $event)
 	{
 		$context = $event->getArgument('0');
-		/* @var TableInterface */
+
+		// @var TableInterface
+
 		$table = $event->getArgument('1');
 		$isNew = $event->getArgument('2');
 		$data  = $event->getArgument('3');
diff --git a/plugins/workflow/notification/notification.php b/plugins/workflow/notification/notification.php
index 81b3f4aee8d36..8a92c65ea292e 100644
--- a/plugins/workflow/notification/notification.php
+++ b/plugins/workflow/notification/notification.php
@@ -144,7 +144,7 @@ public function onWorkflowAfterTransition(WorkflowTransitionEvent $event)
 		$user = $this->app->getIdentity();
 
 		// Prepare Language for messages
-		$default_language = ComponentHelper::getParams('com_languages')->get('administrator');
+		$defaultLanguage = ComponentHelper::getParams('com_languages')->get('administrator');
 		$debug = $this->app->get('debug_lang');
 
 		$modelName = $component->getModelName($context);
@@ -172,20 +172,21 @@ public function onWorkflowAfterTransition(WorkflowTransitionEvent $event)
 
 		// Get the model for private messages
 		$model_message = $this->app->bootComponent('com_messages')
-					->getMVCFactory()->createModel('Message', 'Administrator');
+			->getMVCFactory()->createModel('Message', 'Administrator');
 
 		// Get the title of the stage
 		$model_stage = $this->app->bootComponent('com_workflow')
-					->getMVCFactory()->createModel('Stage', 'Administrator');
+			->getMVCFactory()->createModel('Stage', 'Administrator');
 
 		$toStage = $model_stage->getItem($transition->to_stage_id)->title;
 
 		$hasGetItem = method_exists($model, 'getItem');
+		$container = Factory::getContainer();
 
 		foreach ($pks as $pk)
 		{
 			// Get the title of the item which has changed
-			$title ='';
+			$title = '';
 
 			if ($hasGetItem)
 			{
@@ -195,10 +196,10 @@ public function onWorkflowAfterTransition(WorkflowTransitionEvent $event)
 			// Send Email to receivers
 			foreach ($userIds as $user_id)
 			{
-				$receiver = Factory::getContainer()->get(UserFactoryInterface::class)->loadUserById($user_id);
+				$receiver = $container->get(UserFactoryInterface::class)->loadUserById($user_id);
 
 				// Load language for messaging
-				$lang = Factory::getContainer()->get(LanguageFactoryInterface::class)->createLanguage($user->getParam('admin_language', $default_language), $debug);
+				$lang = $container->get(LanguageFactoryInterface::class)->createLanguage($user->getParam('admin_language', $defaultLanguage), $debug);
 				$lang->load('plg_workflow_notification');
 				$messageText = sprintf($lang->_('PLG_WORKFLOW_NOTIFICATION_ON_TRANSITION_MSG'), $title, $user->name, $lang->_($toStage));
 
@@ -254,7 +255,7 @@ private function getUsersFromGroup($data): Array
 		if (!empty($groups))
 		{
 			// UserIds from usergroups
-			$model =  Factory::getApplication()->bootComponent('com_users')
+			$model = Factory::getApplication()->bootComponent('com_users')
 				->getMVCFactory()->createModel('Users', 'Administrator', ['ignore_request' => true]);
 
 			$model->setState('list.select', 'id');
@@ -329,10 +330,10 @@ private function removeLocked(array $userIds): Array
 		$query = $this->db->getQuery(true);
 
 		$query->select($this->db->quoteName('user_id'))
-				->from($this->db->quoteName('#__messages_cfg'))
-				->whereIn($this->db->quoteName('user_id'), $userIds)
-				->where($this->db->quoteName('cfg_name') . ' = ' . $this->db->quote('locked'))
-				->where($this->db->quoteName('cfg_value') . ' = 1');
+			->from($this->db->quoteName('#__messages_cfg'))
+			->whereIn($this->db->quoteName('user_id'), $userIds)
+			->where($this->db->quoteName('cfg_name') . ' = ' . $this->db->quote('locked'))
+			->where($this->db->quoteName('cfg_value') . ' = 1');
 
 		$locked = $this->db->setQuery($query)->loadColumn();
 
diff --git a/plugins/workflow/publishing/publishing.php b/plugins/workflow/publishing/publishing.php
index 26310a2b38b14..6576eea577afe 100644
--- a/plugins/workflow/publishing/publishing.php
+++ b/plugins/workflow/publishing/publishing.php
@@ -156,7 +156,7 @@ protected function enhanceItemForm(Form $form, $data)
 		$modelName = $component->getModelName($context);
 
 		$table = $component->getMVCFactory()->createModel($modelName, $this->app->getName(), ['ignore_request' => true])
-											 ->getTable();
+			->getTable();
 
 		$fieldname = $table->getColumnAlias('published');
 
@@ -301,7 +301,8 @@ public function onWorkflowBeforeTransition(WorkflowTransitionEvent $event)
 			$context,
 			$pks,
 			$value
-		]);
+			]
+		);
 
 		// Release whitelist, the job is done
 		$this->app->set('plgWorkflowPublishing.' . $context, []);
@@ -399,7 +400,9 @@ public function onContentBeforeChangeState(EventInterface $event)
 	public function onContentBeforeSave(EventInterface $event)
 	{
 		$context = $event->getArgument('0');
-		/* @var TableInterface */
+
+		// @var TableInterface
+
 		$table = $event->getArgument('1');
 		$isNew = $event->getArgument('2');
 		$data  = $event->getArgument('3');