diff --git a/libraries/src/Access/Access.php b/libraries/src/Access/Access.php
index 2dbdf6669d209..3dc92b06a7dfd 100644
--- a/libraries/src/Access/Access.php
+++ b/libraries/src/Access/Access.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Access;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Component\ComponentHelper;
 use Joomla\CMS\Factory;
@@ -186,7 +186,7 @@ public static function preload($assetTypes = 'components', $reload = false)
 		}
 
 		// Check for default case:
-		$isDefault = is_string($assetTypes) && in_array($assetTypes, array('components', 'component'));
+		$isDefault = \is_string($assetTypes) && \in_array($assetTypes, array('components', 'component'));
 
 		// Preload the rules for all of the components.
 		if ($isDefault)
@@ -197,7 +197,7 @@ public static function preload($assetTypes = 'components', $reload = false)
 		}
 
 		// If we get to this point, this is a regular asset type and we'll proceed with the preloading process.
-		if (!is_array($assetTypes))
+		if (!\is_array($assetTypes))
 		{
 			$assetTypes = (array) $assetTypes;
 		}
@@ -1028,7 +1028,7 @@ public static function getAuthorisedViewLevels($userId)
 					break;
 				}
 				// Check to see if the group is mapped to the level.
-				elseif (($id >= 0) && in_array($id, $groups))
+				elseif (($id >= 0) && \in_array($id, $groups))
 				{
 					$authorised[] = $level;
 					break;
@@ -1078,13 +1078,13 @@ public static function getActionsFromFile($file, $xpath = "/access/section[@name
 	public static function getActionsFromData($data, $xpath = "/access/section[@name='component']/")
 	{
 		// If the data to load isn't already an XML element or string return false.
-		if ((!($data instanceof \SimpleXMLElement)) && (!is_string($data)))
+		if ((!($data instanceof \SimpleXMLElement)) && (!\is_string($data)))
 		{
 			return false;
 		}
 
 		// Attempt to load the XML if a string.
-		if (is_string($data))
+		if (\is_string($data))
 		{
 			try
 			{
diff --git a/libraries/src/Access/Exception/AuthenticationFailed.php b/libraries/src/Access/Exception/AuthenticationFailed.php
index 7d6fa9d5a4a15..402bb9519909e 100644
--- a/libraries/src/Access/Exception/AuthenticationFailed.php
+++ b/libraries/src/Access/Exception/AuthenticationFailed.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Access\Exception;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Exception class defining an authentication failed event
diff --git a/libraries/src/Access/Exception/NotAllowed.php b/libraries/src/Access/Exception/NotAllowed.php
index 28e656ba6a700..d927fd0d79bcb 100644
--- a/libraries/src/Access/Exception/NotAllowed.php
+++ b/libraries/src/Access/Exception/NotAllowed.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Access\Exception;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Exception class defining a not allowed access
diff --git a/libraries/src/Access/Rule.php b/libraries/src/Access/Rule.php
index 6a134a059aab5..5004df0db3e7e 100644
--- a/libraries/src/Access/Rule.php
+++ b/libraries/src/Access/Rule.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Access;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Rule class.
@@ -38,7 +38,7 @@ class Rule
 	public function __construct($identities)
 	{
 		// Convert string input to an array.
-		if (is_string($identities))
+		if (\is_string($identities))
 		{
 			$identities = json_decode($identities, true);
 		}
@@ -74,7 +74,7 @@ public function mergeIdentities($identities)
 			$identities = $identities->getData();
 		}
 
-		if (is_array($identities))
+		if (\is_array($identities))
 		{
 			foreach ($identities as $identity => $allow)
 			{
@@ -133,7 +133,7 @@ public function allow($identities)
 		// Check that the inputs are valid.
 		if (!empty($identities))
 		{
-			if (!is_array($identities))
+			if (!\is_array($identities))
 			{
 				$identities = array($identities);
 			}
diff --git a/libraries/src/Access/Rules.php b/libraries/src/Access/Rules.php
index 575563141dab1..41d34bc9c77df 100644
--- a/libraries/src/Access/Rules.php
+++ b/libraries/src/Access/Rules.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Access;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Object\CMSObject;
 
@@ -40,16 +40,16 @@ class Rules
 	public function __construct($input = '')
 	{
 		// Convert in input to an array.
-		if (is_string($input))
+		if (\is_string($input))
 		{
 			$input = json_decode($input, true);
 		}
-		elseif (is_object($input))
+		elseif (\is_object($input))
 		{
 			$input = (array) $input;
 		}
 
-		if (is_array($input))
+		if (\is_array($input))
 		{
 			// Top level keys represent the actions.
 			foreach ($input as $action => $identities)
@@ -83,7 +83,7 @@ public function getData()
 	public function mergeCollection($input)
 	{
 		// Check if the input is an array.
-		if (is_array($input))
+		if (\is_array($input))
 		{
 			foreach ($input as $actions)
 			{
@@ -103,12 +103,12 @@ public function mergeCollection($input)
 	 */
 	public function merge($actions)
 	{
-		if (is_string($actions))
+		if (\is_string($actions))
 		{
 			$actions = json_decode($actions, true);
 		}
 
-		if (is_array($actions))
+		if (\is_array($actions))
 		{
 			foreach ($actions as $action => $identities)
 			{
diff --git a/libraries/src/Application/AdministratorApplication.php b/libraries/src/Application/AdministratorApplication.php
index f2d4eeaf5d119..5e805fbe6f481 100644
--- a/libraries/src/Application/AdministratorApplication.php
+++ b/libraries/src/Application/AdministratorApplication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Application\Web\WebClient;
 use Joomla\CMS\Component\ComponentHelper;
@@ -58,7 +58,7 @@ public function __construct(Input $input = null, Registry $config = null, WebCli
 		parent::__construct($input, $config, $client, $container);
 
 		// Set the root in the URI based on the application name
-		Uri::root(null, rtrim(dirname(Uri::base(true)), '/\\'));
+		Uri::root(null, rtrim(\dirname(Uri::base(true)), '/\\'));
 	}
 
 	/**
@@ -189,7 +189,7 @@ public static function getRouter($name = 'administrator', array $options = array
 	 */
 	public function getTemplate($params = false)
 	{
-		if (is_object($this->template))
+		if (\is_object($this->template))
 		{
 			if ($params)
 			{
@@ -320,7 +320,7 @@ public function login($credentials, $options = array())
 		$options['autoregister'] = false;
 
 		// Set the application login entry point
-		if (!array_key_exists('entry_url', $options))
+		if (!\array_key_exists('entry_url', $options))
 		{
 			$options['entry_url'] = Uri::base() . 'index.php?option=com_users&task=login';
 		}
@@ -368,7 +368,7 @@ public static function purgeMessages()
 		$config = $db->loadObject();
 
 		// Check if auto_purge value set
-		if (is_object($config) && $config->cfg_name === 'auto_purge')
+		if (\is_object($config) && $config->cfg_name === 'auto_purge')
 		{
 			$purge = $config->cfg_value;
 		}
diff --git a/libraries/src/Application/ApiApplication.php b/libraries/src/Application/ApiApplication.php
index d801772aaeaa9..6897e75953402 100644
--- a/libraries/src/Application/ApiApplication.php
+++ b/libraries/src/Application/ApiApplication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Application\Web\WebClient;
 use Joomla\CMS\Access\Exception\AuthenticationFailed;
@@ -125,7 +125,7 @@ protected function doExecute()
 	 */
 	public function addFormatMap($contentHeader, $format)
 	{
-		if (!array_key_exists($contentHeader, $this->formatMapper))
+		if (!\array_key_exists($contentHeader, $this->formatMapper))
 		{
 			$this->formatMapper[$contentHeader] = $format;
 		}
@@ -162,7 +162,7 @@ protected function respond($options = array())
 		// Set the Joomla! API signature
 		$this->setHeader('X-Powered-By', 'JoomlaAPI/1.0', true);
 
-		if (array_key_exists('cors', $options))
+		if (\array_key_exists('cors', $options))
 		{
 			// Enable CORS (Cross-origin resource sharing)
 			$this->setHeader('Access-Control-Allow-Origin', '*', true);
@@ -225,7 +225,7 @@ protected function route()
 		 */
 		$priorities = array('application/vnd.api+json');
 
-		if (!$caught404 && array_key_exists('format', $route['vars']))
+		if (!$caught404 && \array_key_exists('format', $route['vars']))
 		{
 			$priorities = $route['vars']['format'];
 		}
@@ -250,7 +250,7 @@ protected function route()
 		/** @var $mediaType Accept */
 		$format = $mediaType->getValue();
 
-		if (array_key_exists($mediaType->getValue(), $this->formatMapper))
+		if (\array_key_exists($mediaType->getValue(), $this->formatMapper))
 		{
 			$format = $this->formatMapper[$mediaType->getValue()];
 		}
diff --git a/libraries/src/Application/ApplicationHelper.php b/libraries/src/Application/ApplicationHelper.php
index 879bde7159fc1..dbc6d38d903dd 100644
--- a/libraries/src/Application/ApplicationHelper.php
+++ b/libraries/src/Application/ApplicationHelper.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Component\ComponentHelper;
 use Joomla\CMS\Factory;
@@ -197,12 +197,12 @@ public static function getClientInfo($id = null, $byName = false)
 	 */
 	public static function addClientInfo($client)
 	{
-		if (is_array($client))
+		if (\is_array($client))
 		{
 			$client = (object) $client;
 		}
 
-		if (!is_object($client))
+		if (!\is_object($client))
 		{
 			return false;
 		}
@@ -211,7 +211,7 @@ public static function addClientInfo($client)
 
 		if (!isset($client->id))
 		{
-			$client->id = count($info);
+			$client->id = \count($info);
 		}
 
 		self::$_clients[$client->id] = clone $client;
diff --git a/libraries/src/Application/BaseApplication.php b/libraries/src/Application/BaseApplication.php
index 38ec28db1cee3..72d22ec8c8cf9 100644
--- a/libraries/src/Application/BaseApplication.php
+++ b/libraries/src/Application/BaseApplication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Application\AbstractApplication;
 use Joomla\CMS\Input\Input;
diff --git a/libraries/src/Application/CLI/CliInput.php b/libraries/src/Application/CLI/CliInput.php
index 942e28c780592..b6e3c69c0f64f 100644
--- a/libraries/src/Application/CLI/CliInput.php
+++ b/libraries/src/Application/CLI/CliInput.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application\CLI;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Class CliInput
diff --git a/libraries/src/Application/CLI/CliOutput.php b/libraries/src/Application/CLI/CliOutput.php
index 80da0343bcb99..aed0527c9a122 100644
--- a/libraries/src/Application/CLI/CliOutput.php
+++ b/libraries/src/Application/CLI/CliOutput.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application\CLI;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Application\CLI\Output\Processor\ProcessorInterface;
 
diff --git a/libraries/src/Application/CLI/ColorStyle.php b/libraries/src/Application/CLI/ColorStyle.php
index 5f98fbad6afc6..a246ae6bdbfd5 100644
--- a/libraries/src/Application/CLI/ColorStyle.php
+++ b/libraries/src/Application/CLI/ColorStyle.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application\CLI;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Class defining ANSI-color styles for command line output
@@ -102,7 +102,7 @@ public function __construct(string $fg = '', string $bg = '', array $options = [
 	{
 		if ($fg)
 		{
-			if (array_key_exists($fg, static::$knownColors) == false)
+			if (\array_key_exists($fg, static::$knownColors) == false)
 			{
 				throw new \InvalidArgumentException(
 					sprintf(
@@ -118,7 +118,7 @@ public function __construct(string $fg = '', string $bg = '', array $options = [
 
 		if ($bg)
 		{
-			if (array_key_exists($bg, static::$knownColors) == false)
+			if (\array_key_exists($bg, static::$knownColors) == false)
 			{
 				throw new \InvalidArgumentException(
 					sprintf(
@@ -134,7 +134,7 @@ public function __construct(string $fg = '', string $bg = '', array $options = [
 
 		foreach ($options as $option)
 		{
-			if (array_key_exists($option, static::$knownOptions) == false)
+			if (\array_key_exists($option, static::$knownOptions) == false)
 			{
 				throw new \InvalidArgumentException(
 					sprintf(
diff --git a/libraries/src/Application/CLI/Output/Processor/ColorProcessor.php b/libraries/src/Application/CLI/Output/Processor/ColorProcessor.php
index ff399a16c4038..955b902cb04c7 100644
--- a/libraries/src/Application/CLI/Output/Processor/ColorProcessor.php
+++ b/libraries/src/Application/CLI/Output/Processor/ColorProcessor.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application\CLI\Output\Processor;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Application\CLI\ColorStyle;
 
@@ -126,7 +126,7 @@ public function process($string)
 
 		foreach ($matches[0] as $i => $m)
 		{
-			if (array_key_exists($matches[1][$i], $this->styles))
+			if (\array_key_exists($matches[1][$i], $this->styles))
 			{
 				$string = $this->replaceColors($string, $matches[1][$i], $matches[2][$i], $this->styles[$matches[1][$i]]);
 			}
diff --git a/libraries/src/Application/CLI/Output/Processor/ProcessorInterface.php b/libraries/src/Application/CLI/Output/Processor/ProcessorInterface.php
index 9093fc654e712..419ee4c9f7db1 100644
--- a/libraries/src/Application/CLI/Output/Processor/ProcessorInterface.php
+++ b/libraries/src/Application/CLI/Output/Processor/ProcessorInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application\CLI\Output\Processor;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Interface for a command line output processor
diff --git a/libraries/src/Application/CLI/Output/Stdout.php b/libraries/src/Application/CLI/Output/Stdout.php
index 3bd86d97f63c8..95a3d9de57fc3 100644
--- a/libraries/src/Application/CLI/Output/Stdout.php
+++ b/libraries/src/Application/CLI/Output/Stdout.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application\CLI\Output;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Application\CLI\CliOutput;
 
diff --git a/libraries/src/Application/CLI/Output/Xml.php b/libraries/src/Application/CLI/Output/Xml.php
index 40d1063065bc7..126ca3ab9f00f 100644
--- a/libraries/src/Application/CLI/Output/Xml.php
+++ b/libraries/src/Application/CLI/Output/Xml.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application\CLI\Output;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Application\CLI\CliOutput;
 
diff --git a/libraries/src/Application/CMSApplication.php b/libraries/src/Application/CMSApplication.php
index 0b34119fe57b2..757dd13f1db00 100644
--- a/libraries/src/Application/CMSApplication.php
+++ b/libraries/src/Application/CMSApplication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Application\Web\WebClient;
 use Joomla\CMS\Authentication\Authentication;
@@ -149,7 +149,7 @@ public function __construct(Input $input = null, Registry $config = null, WebCli
 		parent::__construct($input, $config, $client);
 
 		// If JDEBUG is defined, load the profiler instance
-		if (defined('JDEBUG') && JDEBUG)
+		if (\defined('JDEBUG') && JDEBUG)
 		{
 			$this->profiler = Profiler::getInstance('Application');
 		}
@@ -206,7 +206,7 @@ public function enqueueMessage($msg, $type = self::MSG_INFO)
 
 		$message = array('message' => $msg, 'type' => strtolower($type));
 
-		if (!in_array($message, $this->messageQueue))
+		if (!\in_array($message, $this->messageQueue))
 		{
 			// Enqueue the message.
 			$this->messageQueue[] = $message;
@@ -465,7 +465,7 @@ public function getMenu($name = null, $options = array())
 	public function getMessageQueue($clear = false)
 	{
 		// For empty queue, if messages exists in the session, enqueue them.
-		if (!count($this->messageQueue))
+		if (!\count($this->messageQueue))
 		{
 			$sessionQueue = $this->getSession()->get('application.queue', []);
 
@@ -816,7 +816,7 @@ public function login($credentials, $options = array())
 				$user->set('cookieLogin', true);
 			}
 
-			if (in_array(false, $results, true) == false)
+			if (\in_array(false, $results, true) == false)
 			{
 				$options['user'] = $user;
 				$options['responseType'] = $response->type;
@@ -885,7 +885,7 @@ public function logout($userid = null, $options = array())
 		$results = $this->triggerEvent('onUserLogout', array($parameters, $options));
 
 		// Check if any of the plugins failed. If none did, success.
-		if (!in_array(false, $results, true))
+		if (!\in_array(false, $results, true))
 		{
 			$options['username'] = $user->get('username');
 			$this->triggerEvent('onUserAfterLogout', array($options));
@@ -916,7 +916,7 @@ public function logout($userid = null, $options = array())
 	public function redirect($url, $status = 303)
 	{
 		// Persist messages if they exist.
-		if (count($this->messageQueue))
+		if (\count($this->messageQueue))
 		{
 			$this->getSession()->set('application.queue', $this->messageQueue);
 		}
@@ -949,7 +949,7 @@ protected function render()
 		// Fall back to constants.
 		else
 		{
-			$this->docOptions['directory'] = defined('JPATH_THEMES') ? JPATH_THEMES : (defined('JPATH_BASE') ? JPATH_BASE : __DIR__) . '/themes';
+			$this->docOptions['directory'] = \defined('JPATH_THEMES') ? JPATH_THEMES : (\defined('JPATH_BASE') ? JPATH_BASE : __DIR__) . '/themes';
 		}
 
 		// Parse the document.
@@ -1004,7 +1004,7 @@ protected function route()
 		if ($active !== null
 			&& $active->type === 'alias'
 			&& $active->params->get('alias_redirect')
-			&& in_array($this->input->getMethod(), array('GET', 'HEAD'), true))
+			&& \in_array($this->input->getMethod(), array('GET', 'HEAD'), true))
 		{
 			$item = $this->getMenu()->getItem($active->params->get('aliasoptions'));
 
@@ -1018,14 +1018,14 @@ protected function route()
 				}
 
 				$base = Uri::base(true);
-				$oldPath = StringHelper::strtolower(substr($oldUri->getPath(), strlen($base) + 1));
+				$oldPath = StringHelper::strtolower(substr($oldUri->getPath(), \strlen($base) + 1));
 				$activePathPrefix = StringHelper::strtolower($active->route);
 
 				$position = strpos($oldPath, $activePathPrefix);
 
 				if ($position !== false)
 				{
-					$oldUri->setPath($base . '/' . substr_replace($oldPath, $item->route, $position, strlen($activePathPrefix)));
+					$oldUri->setPath($base . '/' . substr_replace($oldPath, $item->route, $position, \strlen($activePathPrefix)));
 
 					$this->setHeader('Expires', 'Wed, 17 Aug 2005 00:00:00 GMT', true);
 					$this->setHeader('Last-Modified', gmdate('D, d M Y H:i:s') . ' GMT', true);
diff --git a/libraries/src/Application/CliApplication.php b/libraries/src/Application/CliApplication.php
index 74d3eaa5bbe0b..1a1bde534793f 100644
--- a/libraries/src/Application/CliApplication.php
+++ b/libraries/src/Application/CliApplication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Application\AbstractApplication;
 use Joomla\CMS\Application\CLI\CliInput;
@@ -85,7 +85,7 @@ public function __construct(Input $input = null, Registry $config = null, CliOut
 	)
 	{
 		// Close the application if we are not executed from the command line.
-		if (!defined('STDOUT') || !defined('STDIN') || !isset($_SERVER['argv']))
+		if (!\defined('STDOUT') || !\defined('STDIN') || !isset($_SERVER['argv']))
 		{
 			$this->close();
 		}
@@ -243,7 +243,7 @@ public function setOutput(CliOutput $output)
 	 */
 	public function enqueueMessage($msg, $type = self::MSG_INFO)
 	{
-		if (!array_key_exists($type, $this->messages))
+		if (!\array_key_exists($type, $this->messages))
 		{
 			$this->messages[$type] = [];
 		}
diff --git a/libraries/src/Application/ConsoleApplication.php b/libraries/src/Application/ConsoleApplication.php
index 7b734f4c0fd9a..5d2984c82444b 100644
--- a/libraries/src/Application/ConsoleApplication.php
+++ b/libraries/src/Application/ConsoleApplication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Console;
 use Joomla\CMS\Extension\ExtensionManagerTrait;
diff --git a/libraries/src/Application/DaemonApplication.php b/libraries/src/Application/DaemonApplication.php
index 0cc228402f257..5498a1e58e4bb 100644
--- a/libraries/src/Application/DaemonApplication.php
+++ b/libraries/src/Application/DaemonApplication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Event\BeforeExecuteEvent;
 use Joomla\CMS\Filesystem\Folder;
@@ -114,14 +114,14 @@ abstract class DaemonApplication extends CliApplication
 	public function __construct(Cli $input = null, Registry $config = null, DispatcherInterface $dispatcher = null)
 	{
 		// Verify that the process control extension for PHP is available.
-		if (!defined('SIGHUP'))
+		if (!\defined('SIGHUP'))
 		{
 			Log::add('The PCNTL extension for PHP is not available.', Log::ERROR);
 			throw new \RuntimeException('The PCNTL extension for PHP is not available.');
 		}
 
 		// Verify that POSIX support for PHP is available.
-		if (!function_exists('posix_getpid'))
+		if (!\function_exists('posix_getpid'))
 		{
 			Log::add('The POSIX extension for PHP is not available.', Log::ERROR);
 			throw new \RuntimeException('The POSIX extension for PHP is not available.');
@@ -277,7 +277,7 @@ public function loadConfiguration($data)
 		// The application author name.  This string is used in generating startup scripts and has
 		// a maximum of 50 characters.
 		$tmp = (string) $this->config->get('author_name', 'Joomla Platform');
-		$this->config->set('author_name', (strlen($tmp) > 50) ? substr($tmp, 0, 50) : $tmp);
+		$this->config->set('author_name', (\strlen($tmp) > 50) ? substr($tmp, 0, 50) : $tmp);
 
 		// The application author email.  This string is used in generating startup scripts.
 		$tmp = (string) $this->config->get('author_email', 'admin@joomla.org');
@@ -301,7 +301,7 @@ public function loadConfiguration($data)
 		$this->config->set('application_executable', $tmp);
 
 		// The home directory of the daemon.
-		$tmp = (string) $this->config->get('application_directory', dirname($this->input->executable));
+		$tmp = (string) $this->config->get('application_directory', \dirname($this->input->executable));
 		$this->config->set('application_directory', $tmp);
 
 		// The pid file location.  This defaults to a path inside the /tmp directory.
@@ -696,18 +696,18 @@ protected function setupSignalHandlers()
 		foreach (self::$signals as $signal)
 		{
 			// Ignore signals that are not defined.
-			if (!defined($signal) || !is_int(constant($signal)) || (constant($signal) === 0))
+			if (!\defined($signal) || !\is_int(\constant($signal)) || (\constant($signal) === 0))
 			{
 				// Define the signal to avoid notices.
 				Log::add('Signal "' . $signal . '" not defined. Defining it as null.', Log::DEBUG);
-				define($signal, null);
+				\define($signal, null);
 
 				// Don't listen for signal.
 				continue;
 			}
 
 			// Attach the signal handler for the signal.
-			if (!$this->pcntlSignal(constant($signal), array('DaemonApplication', 'signal')))
+			if (!$this->pcntlSignal(\constant($signal), array('DaemonApplication', 'signal')))
 			{
 				Log::add(sprintf('Unable to reroute signal handler: %s', $signal), Log::EMERGENCY);
 
@@ -801,7 +801,7 @@ protected function writeProcessIdFile()
 		}
 
 		// Make sure that the folder where we are writing the process id file exists.
-		$folder = dirname($file);
+		$folder = \dirname($file);
 
 		if (!is_dir($folder) && !Folder::create($folder))
 		{
diff --git a/libraries/src/Application/EventAware.php b/libraries/src/Application/EventAware.php
index dddd102e4f1d3..3fc94c936a978 100644
--- a/libraries/src/Application/EventAware.php
+++ b/libraries/src/Application/EventAware.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Event\DispatcherInterface;
 use Joomla\Event\Event;
@@ -90,7 +90,7 @@ public function triggerEvent($eventName, $args = [])
 		}
 		catch (\UnexpectedValueException $exception)
 		{
-			$this->getLogger()->error(sprintf('Dispatcher not set in %s, cannot trigger events.', get_class($this)));
+			$this->getLogger()->error(sprintf('Dispatcher not set in %s, cannot trigger events.', \get_class($this)));
 
 			return [];
 		}
@@ -99,7 +99,7 @@ public function triggerEvent($eventName, $args = [])
 		{
 			$event = $args;
 		}
-		elseif (is_array($args))
+		elseif (\is_array($args))
 		{
 			$event = new Event($eventName, $args);
 		}
@@ -111,6 +111,6 @@ public function triggerEvent($eventName, $args = [])
 		$result = $dispatcher->dispatch($eventName, $event);
 
 		// TODO - There are still test cases where the result isn't defined, temporarily leave the isset check in place
-		return !isset($result['result']) || is_null($result['result']) ? [] : $result['result'];
+		return !isset($result['result']) || \is_null($result['result']) ? [] : $result['result'];
 	}
 }
diff --git a/libraries/src/Application/Exception/NotAcceptable.php b/libraries/src/Application/Exception/NotAcceptable.php
index fdb13c14ea1f7..14da7ed2c489e 100644
--- a/libraries/src/Application/Exception/NotAcceptable.php
+++ b/libraries/src/Application/Exception/NotAcceptable.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application\Exception;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Exception class defining a not acceptable class
diff --git a/libraries/src/Application/ExtensionNamespaceMapper.php b/libraries/src/Application/ExtensionNamespaceMapper.php
index 72e3d57f22756..49f9c8927a1ec 100644
--- a/libraries/src/Application/ExtensionNamespaceMapper.php
+++ b/libraries/src/Application/ExtensionNamespaceMapper.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use JLoader;
 
diff --git a/libraries/src/Application/IdentityAware.php b/libraries/src/Application/IdentityAware.php
index 7281b5833e348..823ed92caf21c 100644
--- a/libraries/src/Application/IdentityAware.php
+++ b/libraries/src/Application/IdentityAware.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\User\User;
 use Joomla\CMS\User\UserFactoryInterface;
diff --git a/libraries/src/Application/SiteApplication.php b/libraries/src/Application/SiteApplication.php
index 6a7298ca8194e..e34a27d903d60 100644
--- a/libraries/src/Application/SiteApplication.php
+++ b/libraries/src/Application/SiteApplication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Application\Web\WebClient;
 use Joomla\CMS\Cache\CacheControllerFactoryInterface;
@@ -328,7 +328,7 @@ public function getParams($option = null)
 			$temp = clone ComponentHelper::getParams('com_menus');
 
 			// Lets cascade the parameters if we have menu item parameters
-			if (is_object($menu))
+			if (\is_object($menu))
 			{
 				// Get show_page_heading from com_menu global settings
 				$params[$hash]->def('show_page_heading', $temp->get('show_page_heading'));
@@ -396,7 +396,7 @@ public static function getRouter($name = 'site', array $options = array())
 	 */
 	public function getTemplate($params = false)
 	{
-		if (is_object($this->template))
+		if (\is_object($this->template))
 		{
 			if (!file_exists(JPATH_THEMES . '/' . $this->template->template . '/index.php'))
 			{
@@ -422,7 +422,7 @@ public function getTemplate($params = false)
 
 		$id = 0;
 
-		if (is_object($item))
+		if (\is_object($item))
 		{
 			// Valid item retrieved
 			$id = $item->template_style_id;
@@ -682,7 +682,7 @@ protected function loadLibraryLanguage()
 	public function login($credentials, $options = array())
 	{
 		// Set the application login entry point
-		if (!array_key_exists('entry_url', $options))
+		if (!\array_key_exists('entry_url', $options))
 		{
 			$options['entry_url'] = Uri::base() . 'index.php?option=com_users&task=user.login';
 		}
diff --git a/libraries/src/Application/WebApplication.php b/libraries/src/Application/WebApplication.php
index 3d433e7d3763b..d63a0a2f3eec5 100644
--- a/libraries/src/Application/WebApplication.php
+++ b/libraries/src/Application/WebApplication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Application;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Application\AbstractWebApplication;
 use Joomla\Application\Web\WebClient;
@@ -198,7 +198,7 @@ protected function render()
 		// Fall back to constants.
 		else
 		{
-			$options['directory'] = defined('JPATH_THEMES') ? JPATH_THEMES : (defined('JPATH_BASE') ? JPATH_BASE : __DIR__) . '/themes';
+			$options['directory'] = \defined('JPATH_THEMES') ? JPATH_THEMES : (\defined('JPATH_BASE') ? JPATH_BASE : __DIR__) . '/themes';
 		}
 
 		// Parse the document.
@@ -374,12 +374,12 @@ protected function loadSystemUris($requestUri = null)
 			if (strpos(PHP_SAPI, 'cgi') !== false && !ini_get('cgi.fix_pathinfo') && !empty($_SERVER['REQUEST_URI']))
 			{
 				// We aren't expecting PATH_INFO within PHP_SELF so this should work.
-				$path = dirname($_SERVER['PHP_SELF']);
+				$path = \dirname($_SERVER['PHP_SELF']);
 			}
 			// Pretty much everything else should be handled with SCRIPT_NAME.
 			else
 			{
-				$path = dirname($_SERVER['SCRIPT_NAME']);
+				$path = \dirname($_SERVER['SCRIPT_NAME']);
 			}
 		}
 
@@ -402,7 +402,7 @@ protected function loadSystemUris($requestUri = null)
 		// Set the extended (non-base) part of the request URI as the route.
 		if (stripos($this->get('uri.request'), $this->get('uri.base.full')) === 0)
 		{
-			$this->set('uri.route', substr_replace($this->get('uri.request'), '', 0, strlen($this->get('uri.base.full'))));
+			$this->set('uri.route', substr_replace($this->get('uri.request'), '', 0, \strlen($this->get('uri.base.full'))));
 		}
 
 		// Get an explicitly set media URI is present.
diff --git a/libraries/src/Association/AssociationExtensionHelper.php b/libraries/src/Association/AssociationExtensionHelper.php
index 95b706c25df56..7330a83bacfa9 100644
--- a/libraries/src/Association/AssociationExtensionHelper.php
+++ b/libraries/src/Association/AssociationExtensionHelper.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Association;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Utilities\ArrayHelper;
 
@@ -189,7 +189,7 @@ public function getTypeTitle($typeName)
 	{
 		$type = $this->getType($typeName);
 
-		if (!array_key_exists('title', $type))
+		if (!\array_key_exists('title', $type))
 		{
 			return '';
 		}
@@ -211,7 +211,7 @@ private function getTypeInformation($typeName, $part = 'support')
 	{
 		$type = $this->getType($typeName);
 
-		if (!array_key_exists($part, $type))
+		if (!\array_key_exists($part, $type))
 		{
 			return array();
 		}
@@ -233,7 +233,7 @@ public function getTypeFieldName($typeName, $fieldName)
 	{
 		$fields = $this->getTypeFields($typeName);
 
-		if (!array_key_exists($fieldName, $fields))
+		if (!\array_key_exists($fieldName, $fields))
 		{
 			return '';
 		}
diff --git a/libraries/src/Association/AssociationExtensionInterface.php b/libraries/src/Association/AssociationExtensionInterface.php
index 33802a0bbcc2b..6f935750aa1f8 100644
--- a/libraries/src/Association/AssociationExtensionInterface.php
+++ b/libraries/src/Association/AssociationExtensionInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Association;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Association Extension Interface for the helper classes
diff --git a/libraries/src/Association/AssociationServiceInterface.php b/libraries/src/Association/AssociationServiceInterface.php
index b6b2b863dedfd..d4b932381d0c4 100644
--- a/libraries/src/Association/AssociationServiceInterface.php
+++ b/libraries/src/Association/AssociationServiceInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Association;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * The association service.
diff --git a/libraries/src/Association/AssociationServiceTrait.php b/libraries/src/Association/AssociationServiceTrait.php
index 70e79ef5979cc..fd821a54717a2 100644
--- a/libraries/src/Association/AssociationServiceTrait.php
+++ b/libraries/src/Association/AssociationServiceTrait.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Association;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Trait to implement AssociationServiceInterface
diff --git a/libraries/src/Authentication/Authentication.php b/libraries/src/Authentication/Authentication.php
index aca42d78db98c..9ee4f9fe6929f 100644
--- a/libraries/src/Authentication/Authentication.php
+++ b/libraries/src/Authentication/Authentication.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Factory;
 use Joomla\CMS\Language\Text;
@@ -99,7 +99,7 @@ class Authentication
 	public function __construct(string $pluginType = 'authentication', DispatcherInterface $dispatcher = null)
 	{
 		// Set the dispatcher
-		if (!is_object($dispatcher))
+		if (!\is_object($dispatcher))
 		{
 			$dispatcher = Factory::getContainer()->get('dispatcher');
 		}
diff --git a/libraries/src/Authentication/AuthenticationResponse.php b/libraries/src/Authentication/AuthenticationResponse.php
index 8ef3a04ab9153..14b71ee40c7fd 100644
--- a/libraries/src/Authentication/AuthenticationResponse.php
+++ b/libraries/src/Authentication/AuthenticationResponse.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Authentication response class, provides an object for storing user and error details
diff --git a/libraries/src/Authentication/Password/Argon2iHandler.php b/libraries/src/Authentication/Password/Argon2iHandler.php
index c27bced5d4ca6..a03d188d142b1 100644
--- a/libraries/src/Authentication/Password/Argon2iHandler.php
+++ b/libraries/src/Authentication/Password/Argon2iHandler.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication\Password;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Authentication\Password\Argon2iHandler as BaseArgon2iHandler;
 
diff --git a/libraries/src/Authentication/Password/Argon2idHandler.php b/libraries/src/Authentication/Password/Argon2idHandler.php
index f3fe2df21dfc6..a104b04c2590d 100644
--- a/libraries/src/Authentication/Password/Argon2idHandler.php
+++ b/libraries/src/Authentication/Password/Argon2idHandler.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication\Password;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Authentication\Password\Argon2idHandler as BaseArgon2idHandler;
 
diff --git a/libraries/src/Authentication/Password/BCryptHandler.php b/libraries/src/Authentication/Password/BCryptHandler.php
index eae75813aa9ef..8e81294b3f044 100644
--- a/libraries/src/Authentication/Password/BCryptHandler.php
+++ b/libraries/src/Authentication/Password/BCryptHandler.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication\Password;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Authentication\Password\BCryptHandler as BaseBCryptHandler;
 
diff --git a/libraries/src/Authentication/Password/ChainedHandler.php b/libraries/src/Authentication/Password/ChainedHandler.php
index 38a3941f7d028..85606e8a7eafa 100644
--- a/libraries/src/Authentication/Password/ChainedHandler.php
+++ b/libraries/src/Authentication/Password/ChainedHandler.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication\Password;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Authentication\Password\HandlerInterface;
 
diff --git a/libraries/src/Authentication/Password/CheckIfRehashNeededHandlerInterface.php b/libraries/src/Authentication/Password/CheckIfRehashNeededHandlerInterface.php
index 3e0219bd2ef14..edab3c59a95ea 100644
--- a/libraries/src/Authentication/Password/CheckIfRehashNeededHandlerInterface.php
+++ b/libraries/src/Authentication/Password/CheckIfRehashNeededHandlerInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication\Password;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Interface for a password handler which supports checking if the password requires rehashing
diff --git a/libraries/src/Authentication/Password/MD5Handler.php b/libraries/src/Authentication/Password/MD5Handler.php
index b036f5c606b27..b2fd674ba5ea6 100644
--- a/libraries/src/Authentication/Password/MD5Handler.php
+++ b/libraries/src/Authentication/Password/MD5Handler.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication\Password;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Authentication\Password\HandlerInterface;
 use Joomla\CMS\Crypt\Crypt;
diff --git a/libraries/src/Authentication/Password/PHPassHandler.php b/libraries/src/Authentication/Password/PHPassHandler.php
index 273cff54c8934..a09ff9f8d5389 100644
--- a/libraries/src/Authentication/Password/PHPassHandler.php
+++ b/libraries/src/Authentication/Password/PHPassHandler.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication\Password;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Authentication\Password\HandlerInterface;
 
diff --git a/libraries/src/Authentication/Password/SHA256Handler.php b/libraries/src/Authentication/Password/SHA256Handler.php
index af3704dc9575a..23217a206c83e 100644
--- a/libraries/src/Authentication/Password/SHA256Handler.php
+++ b/libraries/src/Authentication/Password/SHA256Handler.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Authentication\Password;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Authentication\Password\HandlerInterface;
 use Joomla\CMS\Crypt\Crypt;
diff --git a/libraries/src/Autoload/ClassLoader.php b/libraries/src/Autoload/ClassLoader.php
index d7885bfb4da49..bb2821164e71c 100644
--- a/libraries/src/Autoload/ClassLoader.php
+++ b/libraries/src/Autoload/ClassLoader.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Autoload;
 
-defined('_JEXEC') or die;
+\defined('_JEXEC') or die;
 
 use Composer\Autoload\ClassLoader as ComposerClassLoader;
 
diff --git a/libraries/src/Cache/Cache.php b/libraries/src/Cache/Cache.php
index 7d672fcb0422d..bb04f42e2d9dc 100644
--- a/libraries/src/Cache/Cache.php
+++ b/libraries/src/Cache/Cache.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Application\Web\WebClient;
 use Joomla\CMS\Cache\Exception\CacheExceptionInterface;
@@ -548,7 +548,7 @@ public static function getWorkarounds($data, $options = array())
 		}
 
 		// If the pathway buffer is set in the cache data, get it.
-		if (isset($data['pathway']) && is_array($data['pathway']))
+		if (isset($data['pathway']) && \is_array($data['pathway']))
 		{
 			// Push the pathway data into the pathway object.
 			$app->getPathway()->setPathway($data['pathway']);
@@ -556,7 +556,7 @@ public static function getWorkarounds($data, $options = array())
 
 		// @todo check if the following is needed, seems like it should be in page cache
 		// If a module buffer is set in the cache data, get it.
-		if (isset($data['module']) && is_array($data['module']))
+		if (isset($data['module']) && \is_array($data['module']))
 		{
 			// Iterate through the module positions and push them into the document buffer.
 			foreach ($data['module'] as $name => $contents)
@@ -636,13 +636,13 @@ public static function setWorkarounds($data, $options = array())
 			// Get the modules buffer before component execution.
 			$buffer1 = $document->getBuffer();
 
-			if (!is_array($buffer1))
+			if (!\is_array($buffer1))
 			{
 				$buffer1 = array();
 			}
 
 			// Make sure the module buffer is an array.
-			if (!isset($buffer1['module']) || !is_array($buffer1['module']))
+			if (!isset($buffer1['module']) || !\is_array($buffer1['module']))
 			{
 				$buffer1['module'] = array();
 			}
@@ -680,7 +680,7 @@ public static function setWorkarounds($data, $options = array())
 						$newvalue = array_map('unserialize', $newvalue);
 
 						// Special treatment for script and style declarations.
-						if (($now == 'script' || $now == 'style') && is_array($newvalue) && is_array($options['headerbefore'][$now]))
+						if (($now == 'script' || $now == 'style') && \is_array($newvalue) && \is_array($options['headerbefore'][$now]))
 						{
 							foreach ($newvalue as $type => $currentScriptStr)
 							{
@@ -720,7 +720,7 @@ public static function setWorkarounds($data, $options = array())
 		// Pathway data
 		if ($app->isClient('site') && $loptions['nopathway'] != 1)
 		{
-			$cached['pathway'] = is_array($data) && isset($data['pathway']) ? $data['pathway'] : $app->getPathway()->getPathway();
+			$cached['pathway'] = \is_array($data) && isset($data['pathway']) ? $data['pathway'] : $app->getPathway()->getPathway();
 		}
 
 		if ($loptions['nomodules'] != 1)
@@ -729,13 +729,13 @@ public static function setWorkarounds($data, $options = array())
 			// Get the module buffer after component execution.
 			$buffer2 = $document->getBuffer();
 
-			if (!is_array($buffer2))
+			if (!\is_array($buffer2))
 			{
 				$buffer2 = array();
 			}
 
 			// Make sure the module buffer is an array.
-			if (!isset($buffer2['module']) || !is_array($buffer2['module']))
+			if (!isset($buffer2['module']) || !\is_array($buffer2['module']))
 			{
 				$buffer2['module'] = array();
 			}
@@ -844,7 +844,7 @@ public static function addIncludePath($path = '')
 			$paths = array();
 		}
 
-		if (!empty($path) && !in_array($path, $paths))
+		if (!empty($path) && !\in_array($path, $paths))
 		{
 			array_unshift($paths, Path::clean($path));
 		}
diff --git a/libraries/src/Cache/CacheController.php b/libraries/src/Cache/CacheController.php
index 4abe45af7ad1f..bfa0e67e129cd 100644
--- a/libraries/src/Cache/CacheController.php
+++ b/libraries/src/Cache/CacheController.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Factory;
 use Joomla\CMS\Filesystem\Path;
@@ -71,7 +71,7 @@ public function __construct($options)
 	 */
 	public function __call($name, $arguments)
 	{
-		return call_user_func_array(array($this->cache, $name), $arguments);
+		return \call_user_func_array(array($this->cache, $name), $arguments);
 	}
 
 	/**
@@ -152,7 +152,7 @@ public static function addIncludePath($path = '')
 			$paths = array();
 		}
 
-		if (!empty($path) && !in_array($path, $paths))
+		if (!empty($path) && !\in_array($path, $paths))
 		{
 			// Only trigger a deprecation notice when adding a lookup path
 			@trigger_error(
diff --git a/libraries/src/Cache/CacheControllerFactory.php b/libraries/src/Cache/CacheControllerFactory.php
index 133c7013f37aa..b215984a8bee8 100644
--- a/libraries/src/Cache/CacheControllerFactory.php
+++ b/libraries/src/Cache/CacheControllerFactory.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache;
 
-defined('_JEXEC') or die;
+\defined('_JEXEC') or die;
 
 /**
  * Default factory for creating CacheController objects
diff --git a/libraries/src/Cache/CacheControllerFactoryInterface.php b/libraries/src/Cache/CacheControllerFactoryInterface.php
index 2118dcebf7196..4dd7ba0c939cb 100644
--- a/libraries/src/Cache/CacheControllerFactoryInterface.php
+++ b/libraries/src/Cache/CacheControllerFactoryInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache;
 
-defined('_JEXEC') or die;
+\defined('_JEXEC') or die;
 
 /**
  * Interface defining a factory which can create CacheController objects
diff --git a/libraries/src/Cache/CacheStorage.php b/libraries/src/Cache/CacheStorage.php
index 94eb1d16ab88a..539b77ab9dbf3 100644
--- a/libraries/src/Cache/CacheStorage.php
+++ b/libraries/src/Cache/CacheStorage.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\Exception\UnsupportedCacheException;
 use Joomla\CMS\Factory;
@@ -135,7 +135,7 @@ public static function getInstance($handler = null, $options = array())
 			}
 		}
 
-		if (is_null($now))
+		if (\is_null($now))
 		{
 			$now = time();
 		}
@@ -376,7 +376,7 @@ public static function addIncludePath($path = '')
 			$paths = array();
 		}
 
-		if (!empty($path) && !in_array($path, $paths))
+		if (!empty($path) && !\in_array($path, $paths))
 		{
 			array_unshift($paths, Path::clean($path));
 		}
diff --git a/libraries/src/Cache/Controller/CallbackController.php b/libraries/src/Cache/Controller/CallbackController.php
index 8574a03028354..34b5911924340 100644
--- a/libraries/src/Cache/Controller/CallbackController.php
+++ b/libraries/src/Cache/Controller/CallbackController.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Controller;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\Cache;
 use Joomla\CMS\Cache\CacheController;
@@ -81,7 +81,7 @@ public function get($callback, $args = array(), $id = false, $wrkarounds = false
 			return $data['result'];
 		}
 
-		if (!is_array($args))
+		if (!\is_array($args))
 		{
 			$referenceArgs = !empty($args) ? array(&$args) : array();
 		}
@@ -93,7 +93,7 @@ public function get($callback, $args = array(), $id = false, $wrkarounds = false
 		if ($locktest->locked === false && $locktest->locklooped === true)
 		{
 			// We can not store data because another process is in the middle of saving
-			return call_user_func_array($callback, $referenceArgs);
+			return \call_user_func_array($callback, $referenceArgs);
 		}
 
 		$coptions = array();
@@ -121,7 +121,7 @@ public function get($callback, $args = array(), $id = false, $wrkarounds = false
 		ob_start();
 		ob_implicit_flush(false);
 
-		$result = call_user_func_array($callback, $referenceArgs);
+		$result = \call_user_func_array($callback, $referenceArgs);
 		$output = ob_get_clean();
 
 		$data = array('result' => $result);
@@ -192,10 +192,10 @@ public function store($data, $id, $group = null, $wrkarounds = true)
 	 */
 	protected function _makeId($callback, $args)
 	{
-		if (is_array($callback) && is_object($callback[0]))
+		if (\is_array($callback) && \is_object($callback[0]))
 		{
 			$vars        = get_object_vars($callback[0]);
-			$vars[]      = strtolower(get_class($callback[0]));
+			$vars[]      = strtolower(\get_class($callback[0]));
 			$callback[0] = $vars;
 		}
 
diff --git a/libraries/src/Cache/Controller/OutputController.php b/libraries/src/Cache/Controller/OutputController.php
index 2ac5067045a92..f06ee7aa53b68 100644
--- a/libraries/src/Cache/Controller/OutputController.php
+++ b/libraries/src/Cache/Controller/OutputController.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Controller;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\CacheController;
 
diff --git a/libraries/src/Cache/Controller/PageController.php b/libraries/src/Cache/Controller/PageController.php
index 252a1af8a6ffe..004ff4aa17622 100644
--- a/libraries/src/Cache/Controller/PageController.php
+++ b/libraries/src/Cache/Controller/PageController.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Controller;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\Cache;
 use Joomla\CMS\Cache\CacheController;
diff --git a/libraries/src/Cache/Controller/ViewController.php b/libraries/src/Cache/Controller/ViewController.php
index 0bb45e8b22054..491a08c428885 100644
--- a/libraries/src/Cache/Controller/ViewController.php
+++ b/libraries/src/Cache/Controller/ViewController.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Controller;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\Cache;
 use Joomla\CMS\Cache\CacheController;
@@ -168,6 +168,6 @@ public function store($data, $id, $group = null, $wrkarounds = true)
 	 */
 	protected function _makeId($view, $method)
 	{
-		return md5(serialize(array(Cache::makeId(), get_class($view), $method)));
+		return md5(serialize(array(Cache::makeId(), \get_class($view), $method)));
 	}
 }
diff --git a/libraries/src/Cache/Exception/CacheConnectingException.php b/libraries/src/Cache/Exception/CacheConnectingException.php
index 9acb2b0119f02..e5bc341d0812d 100644
--- a/libraries/src/Cache/Exception/CacheConnectingException.php
+++ b/libraries/src/Cache/Exception/CacheConnectingException.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Exception;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Exception class defining an error connecting to the cache storage engine
diff --git a/libraries/src/Cache/Exception/CacheExceptionInterface.php b/libraries/src/Cache/Exception/CacheExceptionInterface.php
index a4f944f95239a..9186f20341a21 100644
--- a/libraries/src/Cache/Exception/CacheExceptionInterface.php
+++ b/libraries/src/Cache/Exception/CacheExceptionInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Exception;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Exception interface defining a cache storage error
diff --git a/libraries/src/Cache/Exception/UnsupportedCacheException.php b/libraries/src/Cache/Exception/UnsupportedCacheException.php
index 0430f2e21402d..b6492ae2c880a 100644
--- a/libraries/src/Cache/Exception/UnsupportedCacheException.php
+++ b/libraries/src/Cache/Exception/UnsupportedCacheException.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Exception;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Exception class defining an unsupported cache storage object
diff --git a/libraries/src/Cache/Storage/ApcuStorage.php b/libraries/src/Cache/Storage/ApcuStorage.php
index 86b37cd4b31aa..549f64591472a 100644
--- a/libraries/src/Cache/Storage/ApcuStorage.php
+++ b/libraries/src/Cache/Storage/ApcuStorage.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Storage;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\CacheStorage;
 
@@ -242,7 +242,7 @@ public function gc()
 	 */
 	public static function isSupported()
 	{
-		$supported = extension_loaded('apcu') && ini_get('apc.enabled');
+		$supported = \extension_loaded('apcu') && ini_get('apc.enabled');
 
 		// If on the CLI interface, the `apc.enable_cli` option must also be enabled
 		if ($supported && PHP_SAPI === 'cli')
diff --git a/libraries/src/Cache/Storage/CacheStorageHelper.php b/libraries/src/Cache/Storage/CacheStorageHelper.php
index 762abb45cd51a..8f3939c39bd1d 100644
--- a/libraries/src/Cache/Storage/CacheStorageHelper.php
+++ b/libraries/src/Cache/Storage/CacheStorageHelper.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Storage;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Cache storage helper functions.
diff --git a/libraries/src/Cache/Storage/FileStorage.php b/libraries/src/Cache/Storage/FileStorage.php
index 25008679ac0c7..f6e0cf1f20f35 100644
--- a/libraries/src/Cache/Storage/FileStorage.php
+++ b/libraries/src/Cache/Storage/FileStorage.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Storage;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\CacheStorage;
 use Joomla\CMS\Factory;
@@ -60,7 +60,7 @@ public function __construct($options = array())
 		{
 			foreach ($locked_files as $path => $handle)
 			{
-				if (is_resource($handle))
+				if (\is_resource($handle))
 				{
 					@flock($handle, LOCK_UN);
 					@fclose($handle);
@@ -213,7 +213,7 @@ public function store($id, $group, $data)
 
 		if ($_fileopen)
 		{
-			$length = strlen($data);
+			$length = \strlen($data);
 			$result = @fwrite($_fileopen, $data, $length);
 
 			if ($close)
@@ -277,7 +277,7 @@ public function clean($group, $mode = null)
 			case 'notgroup' :
 				$folders = $this->_folders($this->_root);
 
-				for ($i = 0, $n = count($folders); $i < $n; $i++)
+				for ($i = 0, $n = \count($folders); $i < $n; $i++)
 				{
 					if ($folders[$i] != $folder)
 					{
@@ -522,14 +522,14 @@ protected function _deleteFolder($path)
 		// Remove all the files in folder if they exist; disable all filtering
 		$files = $this->_filesInFolder($path, '.', false, true, array(), array());
 
-		if (!empty($files) && !is_array($files))
+		if (!empty($files) && !\is_array($files))
 		{
 			if (@unlink($files) !== true)
 			{
 				return false;
 			}
 		}
-		elseif (!empty($files) && is_array($files))
+		elseif (!empty($files) && \is_array($files))
 		{
 			foreach ($files as $file)
 			{
@@ -636,7 +636,7 @@ protected function _filesInFolder($path, $filter = '.', $recurse = false, $fullp
 			return $arr;
 		}
 
-		if (count($excludefilter))
+		if (\count($excludefilter))
 		{
 			$excludefilter = '/(' . implode('|', $excludefilter) . ')/';
 		}
@@ -647,7 +647,7 @@ protected function _filesInFolder($path, $filter = '.', $recurse = false, $fullp
 
 		while (($file = readdir($handle)) !== false)
 		{
-			if (($file != '.') && ($file != '..') && (!in_array($file, $exclude)) && (!$excludefilter || !preg_match($excludefilter, $file)))
+			if (($file != '.') && ($file != '..') && (!\in_array($file, $exclude)) && (!$excludefilter || !preg_match($excludefilter, $file)))
 			{
 				$dir   = $path . '/' . $file;
 				$isDir = is_dir($dir);
@@ -656,7 +656,7 @@ protected function _filesInFolder($path, $filter = '.', $recurse = false, $fullp
 				{
 					if ($recurse)
 					{
-						if (is_int($recurse))
+						if (\is_int($recurse))
 						{
 							$arr2 = $this->_filesInFolder($dir, $filter, $recurse - 1, $fullpath);
 						}
@@ -726,7 +726,7 @@ protected function _folders($path, $filter = '.', $recurse = false, $fullpath =
 			return $arr;
 		}
 
-		if (count($excludefilter))
+		if (\count($excludefilter))
 		{
 			$excludefilter_string = '/(' . implode('|', $excludefilter) . ')/';
 		}
@@ -738,7 +738,7 @@ protected function _folders($path, $filter = '.', $recurse = false, $fullpath =
 		while (($file = readdir($handle)) !== false)
 		{
 			if (($file != '.') && ($file != '..')
-				&& (!in_array($file, $exclude))
+				&& (!\in_array($file, $exclude))
 				&& (empty($excludefilter_string) || !preg_match($excludefilter_string, $file)))
 			{
 				$dir   = $path . '/' . $file;
@@ -761,7 +761,7 @@ protected function _folders($path, $filter = '.', $recurse = false, $fullpath =
 
 					if ($recurse)
 					{
-						if (is_int($recurse))
+						if (\is_int($recurse))
 						{
 							$arr2 = $this->_folders($dir, $filter, $recurse - 1, $fullpath, $exclude, $excludefilter);
 						}
diff --git a/libraries/src/Cache/Storage/MemcachedStorage.php b/libraries/src/Cache/Storage/MemcachedStorage.php
index 67da648b7fa42..d215c9a708ed2 100644
--- a/libraries/src/Cache/Storage/MemcachedStorage.php
+++ b/libraries/src/Cache/Storage/MemcachedStorage.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Storage;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\Cache;
 use Joomla\CMS\Cache\CacheStorage;
@@ -129,7 +129,7 @@ protected function getConnection()
 	protected function _getCacheId($id, $group)
 	{
 		$prefix   = Cache::getPlatformPrefix();
-		$length   = strlen($prefix);
+		$length   = \strlen($prefix);
 		$cache_id = parent::_getCacheId($id, $group);
 
 		if ($length)
@@ -188,7 +188,7 @@ public function getAll()
 
 		$data = array();
 
-		if (is_array($keys))
+		if (\is_array($keys))
 		{
 			foreach ($keys as $key)
 			{
@@ -244,14 +244,14 @@ public function store($id, $group, $data)
 
 		$index = static::$_db->get($this->_hash . '-index');
 
-		if (!is_array($index))
+		if (!\is_array($index))
 		{
 			$index = array();
 		}
 
 		$tmparr       = new \stdClass;
 		$tmparr->name = $cache_id;
-		$tmparr->size = strlen($data);
+		$tmparr->size = \strlen($data);
 
 		$index[] = $tmparr;
 		static::$_db->set($this->_hash . '-index', $index, 0);
@@ -283,7 +283,7 @@ public function remove($id, $group)
 
 		$index = static::$_db->get($this->_hash . '-index');
 
-		if (is_array($index))
+		if (\is_array($index))
 		{
 			foreach ($index as $key => $value)
 			{
@@ -323,7 +323,7 @@ public function clean($group, $mode = null)
 
 		$index = static::$_db->get($this->_hash . '-index');
 
-		if (is_array($index))
+		if (\is_array($index))
 		{
 			$prefix = $this->_hash . '-cache-' . $group . '-';
 
diff --git a/libraries/src/Cache/Storage/RedisStorage.php b/libraries/src/Cache/Storage/RedisStorage.php
index 02a83cb7a9c45..b85f43113dd89 100644
--- a/libraries/src/Cache/Storage/RedisStorage.php
+++ b/libraries/src/Cache/Storage/RedisStorage.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Storage;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\CacheStorage;
 use Joomla\CMS\Cache\Exception\CacheConnectingException;
@@ -231,7 +231,7 @@ public function getAll()
 						$item = $data[$group];
 					}
 
-					$item->updateSize(strlen($key)*8);
+					$item->updateSize(\strlen($key)*8);
 					$data[$group] = $item;
 				}
 			}
diff --git a/libraries/src/Cache/Storage/WincacheStorage.php b/libraries/src/Cache/Storage/WincacheStorage.php
index a5f4b7ddfc1b2..37e06690d73ab 100644
--- a/libraries/src/Cache/Storage/WincacheStorage.php
+++ b/libraries/src/Cache/Storage/WincacheStorage.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Cache\Storage;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Cache\CacheStorage;
 
@@ -194,6 +194,6 @@ public function gc()
 	 */
 	public static function isSupported()
 	{
-		return extension_loaded('wincache') && function_exists('wincache_ucache_get') && !strcmp(ini_get('wincache.ucenabled'), '1');
+		return \extension_loaded('wincache') && \function_exists('wincache_ucache_get') && !strcmp(ini_get('wincache.ucenabled'), '1');
 	}
 }
diff --git a/libraries/src/Captcha/Captcha.php b/libraries/src/Captcha/Captcha.php
index 3f514aea5620a..b46ef5f802c70 100644
--- a/libraries/src/Captcha/Captcha.php
+++ b/libraries/src/Captcha/Captcha.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Captcha;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Factory;
 use Joomla\CMS\Filter\InputFilter;
diff --git a/libraries/src/Captcha/Google/HttpBridgePostRequestMethod.php b/libraries/src/Captcha/Google/HttpBridgePostRequestMethod.php
index 888e52a8d86da..4147b68dfc886 100644
--- a/libraries/src/Captcha/Google/HttpBridgePostRequestMethod.php
+++ b/libraries/src/Captcha/Google/HttpBridgePostRequestMethod.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Captcha\Google;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Http\HttpFactory;
 use Joomla\Http\Exception\InvalidResponseCodeException;
diff --git a/libraries/src/Categories/Categories.php b/libraries/src/Categories/Categories.php
index 8809520a84f93..9780d53c4efd4 100644
--- a/libraries/src/Categories/Categories.php
+++ b/libraries/src/Categories/Categories.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Categories;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Factory;
 use Joomla\CMS\Language\Multilanguage;
@@ -145,7 +145,7 @@ public static function getInstance($extension, $options = array())
 
 			if ($component instanceof CategoryServiceInterface)
 			{
-				$categories = $component->getCategory($options, count($parts) > 1 ? $parts[1] : '');
+				$categories = $component->getCategory($options, \count($parts) > 1 ? $parts[1] : '');
 			}
 		}
 		catch (SectionNotFoundException $e)
@@ -321,7 +321,7 @@ protected function _load($id)
 		$results = $db->loadObjectList('id');
 		$childrenLoaded = false;
 
-		if (count($results))
+		if (\count($results))
 		{
 			// Foreach categories
 			foreach ($results as $result)
diff --git a/libraries/src/Categories/CategoryFactory.php b/libraries/src/Categories/CategoryFactory.php
index 93cd899ac00e9..6a9926d4af0cb 100644
--- a/libraries/src/Categories/CategoryFactory.php
+++ b/libraries/src/Categories/CategoryFactory.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Categories;
 
-defined('_JEXEC') or die;
+\defined('_JEXEC') or die;
 
 /**
  * Option based categories factory.
diff --git a/libraries/src/Categories/CategoryFactoryInterface.php b/libraries/src/Categories/CategoryFactoryInterface.php
index 953f68aeec246..5586ccb8098ea 100644
--- a/libraries/src/Categories/CategoryFactoryInterface.php
+++ b/libraries/src/Categories/CategoryFactoryInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Categories;
 
-defined('_JEXEC') or die;
+\defined('_JEXEC') or die;
 
 /**
  * Category factory interface
diff --git a/libraries/src/Categories/CategoryInterface.php b/libraries/src/Categories/CategoryInterface.php
index e431959082db0..5145fd3808799 100644
--- a/libraries/src/Categories/CategoryInterface.php
+++ b/libraries/src/Categories/CategoryInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Categories;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * The category interface.
diff --git a/libraries/src/Categories/CategoryNode.php b/libraries/src/Categories/CategoryNode.php
index f0eb020e4bc23..41c7d27b6af8c 100644
--- a/libraries/src/Categories/CategoryNode.php
+++ b/libraries/src/Categories/CategoryNode.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Categories;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Factory;
 use Joomla\CMS\Object\CMSObject;
@@ -311,7 +311,7 @@ public function __construct($category = null, $constructor = null)
 	 */
 	public function setParent(NodeInterface $parent)
 	{
-		if (!is_null($this->_parent))
+		if (!\is_null($this->_parent))
 		{
 			$key = array_search($this, $this->_parent->_children);
 			unset($this->_parent->_children[$key]);
@@ -321,7 +321,7 @@ public function setParent(NodeInterface $parent)
 
 		$this->_parent->_children[] = & $this;
 
-		if (count($this->_parent->_children) > 1)
+		if (\count($this->_parent->_children) > 1)
 		{
 			end($this->_parent->_children);
 			$this->_leftSibling = prev($this->_parent->_children);
diff --git a/libraries/src/Categories/CategoryServiceInterface.php b/libraries/src/Categories/CategoryServiceInterface.php
index 6f5a126b26a6d..29d6ea35f103f 100644
--- a/libraries/src/Categories/CategoryServiceInterface.php
+++ b/libraries/src/Categories/CategoryServiceInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Categories;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Form\Form;
 
diff --git a/libraries/src/Categories/CategoryServiceTrait.php b/libraries/src/Categories/CategoryServiceTrait.php
index c913ca0c722ca..ca6d58ae7dfc8 100644
--- a/libraries/src/Categories/CategoryServiceTrait.php
+++ b/libraries/src/Categories/CategoryServiceTrait.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Categories;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Form\Form;
 use Joomla\CMS\Helper\ContentHelper;
@@ -95,7 +95,7 @@ public function countItems(array $items, string $section)
 	public function countTagItems(array $items, string $extension)
 	{
 		$parts   = explode('.', $extension);
-		$section = count($parts) > 1 ? $parts[1] : null;
+		$section = \count($parts) > 1 ? $parts[1] : null;
 
 		$config = (object) array(
 			'related_tbl'   => $this->getTableNameForSection($section),
diff --git a/libraries/src/Changelog/Changelog.php b/libraries/src/Changelog/Changelog.php
index 6d3461dabb3cc..fc46ccc6c49e3 100644
--- a/libraries/src/Changelog/Changelog.php
+++ b/libraries/src/Changelog/Changelog.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Changelog;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Http\HttpFactory;
 use Joomla\CMS\Language\Text;
@@ -174,7 +174,7 @@ protected function getStackLocation()
 	 */
 	protected function getLastTag()
 	{
-		return $this->stack[count($this->stack) - 1];
+		return $this->stack[\count($this->stack) - 1];
 	}
 
 	/**
diff --git a/libraries/src/Client/ClientHelper.php b/libraries/src/Client/ClientHelper.php
index a6b839f786fdd..85122adc0410b 100644
--- a/libraries/src/Client/ClientHelper.php
+++ b/libraries/src/Client/ClientHelper.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Client;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Factory;
 
diff --git a/libraries/src/Client/FtpClient.php b/libraries/src/Client/FtpClient.php
index 43dc0184f75c8..b4f4f26675878 100644
--- a/libraries/src/Client/FtpClient.php
+++ b/libraries/src/Client/FtpClient.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Client;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Language\Text;
 use Joomla\CMS\Log\Log;
@@ -26,7 +26,7 @@
  * - 38 : Local filesystem error
  */
 
-if (!defined('CRLF'))
+if (!\defined('CRLF'))
 {
 	/**
 	 * Constant defining a line break
@@ -34,10 +34,10 @@
 	 * @var    string
 	 * @since  1.5
 	 */
-	define('CRLF', "\r\n");
+	\define('CRLF', "\r\n");
 }
 
-if (!defined('FTP_AUTOASCII'))
+if (!\defined('FTP_AUTOASCII'))
 {
 	/**
 	 * Constant defining whether the FTP connection type will automatically determine ASCII support based on a file extension
@@ -45,10 +45,10 @@
 	 * @var    integer
 	 * @since  1.5
 	 */
-	define('FTP_AUTOASCII', -1);
+	\define('FTP_AUTOASCII', -1);
 }
 
-if (!defined('FTP_BINARY'))
+if (!\defined('FTP_BINARY'))
 {
 	/**
 	 * Stub of the native FTP_BINARY constant if PHP is running without the ftp extension enabled
@@ -56,10 +56,10 @@
 	 * @var    integer
 	 * @since  1.5
 	 */
-	define('FTP_BINARY', 1);
+	\define('FTP_BINARY', 1);
 }
 
-if (!defined('FTP_ASCII'))
+if (!\defined('FTP_ASCII'))
 {
 	/**
 	 * Stub of the native FTP_ASCII constant if PHP is running without the ftp extension enabled
@@ -67,10 +67,10 @@
 	 * @var    integer
 	 * @since  1.5
 	 */
-	define('FTP_ASCII', 0);
+	\define('FTP_ASCII', 0);
 }
 
-if (!defined('FTP_NATIVE'))
+if (!\defined('FTP_NATIVE'))
 {
 	/**
 	 * Constant defining whether native FTP support is available on the platform
@@ -78,7 +78,7 @@
 	 * @var    integer
 	 * @since  1.5
 	 */
-	define('FTP_NATIVE', function_exists('ftp_connect') ? 1 : 0);
+	\define('FTP_NATIVE', \function_exists('ftp_connect') ? 1 : 0);
 }
 
 /**
@@ -198,7 +198,7 @@ public function __construct(array $options = array())
 	 */
 	public function __destruct()
 	{
-		if (is_resource($this->_conn))
+		if (\is_resource($this->_conn))
 		{
 			$this->quit();
 		}
@@ -228,7 +228,7 @@ public static function getInstance($host = '127.0.0.1', $port = '21', array $opt
 		$signature = $user . ':' . $pass . '@' . $host . ':' . $port;
 
 		// Create a new instance, or set the options of an existing one
-		if (!isset(static::$instances[$signature]) || !is_object(static::$instances[$signature]))
+		if (!isset(static::$instances[$signature]) || !\is_object(static::$instances[$signature]))
 		{
 			static::$instances[$signature] = new static($options);
 		}
@@ -291,7 +291,7 @@ public function connect($host = '127.0.0.1', $port = 21)
 		$err = null;
 
 		// If already connected, return
-		if (is_resource($this->_conn))
+		if (\is_resource($this->_conn))
 		{
 			return true;
 		}
@@ -347,7 +347,7 @@ public function connect($host = '127.0.0.1', $port = 21)
 	 */
 	public function isConnected()
 	{
-		return is_resource($this->_conn);
+		return \is_resource($this->_conn);
 	}
 
 	/**
@@ -392,7 +392,7 @@ public function login($user = 'anonymous', $pass = 'jftp@joomla.org')
 		// Send the password
 		if (!$this->_putCmd('PASS ' . $pass, 230))
 		{
-			Log::add(Text::sprintf('JLIB_CLIENT_ERROR_JFTP_BAD_PASSWORD', $this->_response, str_repeat('*', strlen($pass))), Log::WARNING, 'jerror');
+			Log::add(Text::sprintf('JLIB_CLIENT_ERROR_JFTP_BAD_PASSWORD', $this->_response, str_repeat('*', \strlen($pass))), Log::WARNING, 'jerror');
 
 			return false;
 		}
@@ -646,7 +646,7 @@ public function chmod($path, $mode)
 		}
 
 		// Convert the mode to a string
-		if (is_int($mode))
+		if (\is_int($mode))
 		{
 			$mode = decoct($mode);
 		}
@@ -1672,7 +1672,7 @@ public function listDetails($path = null, $type = 'all')
 					continue;
 				}
 
-				if (is_array($tmp_array) && $tmp_array['name'] != '.' && $tmp_array['name'] != '..')
+				if (\is_array($tmp_array) && $tmp_array['name'] != '.' && $tmp_array['name'] != '..')
 				{
 					$dir_list[] = $tmp_array;
 				}
@@ -1714,7 +1714,7 @@ public function listDetails($path = null, $type = 'all')
 					continue;
 				}
 
-				if (is_array($tmp_array) && $tmp_array['name'] != '.' && $tmp_array['name'] != '..')
+				if (\is_array($tmp_array) && $tmp_array['name'] != '.' && $tmp_array['name'] != '..')
 				{
 					$dir_list[] = $tmp_array;
 				}
@@ -1737,7 +1737,7 @@ public function listDetails($path = null, $type = 'all')
 	protected function _putCmd($cmd, $expectedResponse)
 	{
 		// Make sure we have a connection to the server
-		if (!is_resource($this->_conn))
+		if (!\is_resource($this->_conn))
 		{
 			Log::add(Text::_('JLIB_CLIENT_ERROR_JFTP_PUTCMD_UNCONNECTED'), Log::WARNING, 'jerror');
 
@@ -1789,9 +1789,9 @@ protected function _verifyResponse($expected)
 		$this->_responseMsg = $parts[0];
 
 		// Did the server respond with the code we wanted?
-		if (is_array($expected))
+		if (\is_array($expected))
 		{
-			if (in_array($this->_responseCode, $expected))
+			if (\in_array($this->_responseCode, $expected))
 			{
 				$retval = true;
 			}
@@ -1830,7 +1830,7 @@ protected function _passive()
 		$err = null;
 
 		// Make sure we have a connection to the server
-		if (!is_resource($this->_conn))
+		if (!\is_resource($this->_conn))
 		{
 			Log::add(Text::_('JLIB_CLIENT_ERROR_JFTP_PASSIVE_CONNECT_PORT'), Log::WARNING, 'jerror');
 
@@ -1917,7 +1917,7 @@ protected function _findMode($fileName)
 			$dot = strrpos($fileName, '.') + 1;
 			$ext = substr($fileName, $dot);
 
-			if (in_array($ext, $this->_autoAscii))
+			if (\in_array($ext, $this->_autoAscii))
 			{
 				$mode = FTP_ASCII;
 			}
diff --git a/libraries/src/Component/ComponentHelper.php b/libraries/src/Component/ComponentHelper.php
index 30d0967246a35..35a02bb56b37e 100644
--- a/libraries/src/Component/ComponentHelper.php
+++ b/libraries/src/Component/ComponentHelper.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Access\Access;
 use Joomla\CMS\Cache\CacheControllerFactoryInterface;
@@ -335,7 +335,7 @@ public static function renderComponent($option, $params = array())
 
 		// Define component path.
 
-		if (!defined('JPATH_COMPONENT'))
+		if (!\defined('JPATH_COMPONENT'))
 		{
 			/**
 			 * Defines the path to the active component for the request
@@ -346,10 +346,10 @@ public static function renderComponent($option, $params = array())
 			 * @since  1.5
 			 * @deprecated 5.0 without replacement
 			 */
-			define('JPATH_COMPONENT', JPATH_BASE . '/components/' . $option);
+			\define('JPATH_COMPONENT', JPATH_BASE . '/components/' . $option);
 		}
 
-		if (!defined('JPATH_COMPONENT_SITE'))
+		if (!\defined('JPATH_COMPONENT_SITE'))
 		{
 			/**
 			 * Defines the path to the site element of the active component for the request
@@ -358,10 +358,10 @@ public static function renderComponent($option, $params = array())
 			 * @since  1.5
 			 * @deprecated 5.0 without replacement
 			 */
-			define('JPATH_COMPONENT_SITE', JPATH_SITE . '/components/' . $option);
+			\define('JPATH_COMPONENT_SITE', JPATH_SITE . '/components/' . $option);
 		}
 
-		if (!defined('JPATH_COMPONENT_ADMINISTRATOR'))
+		if (!\defined('JPATH_COMPONENT_ADMINISTRATOR'))
 		{
 			/**
 			 * Defines the path to the admin element of the active component for the request
@@ -370,7 +370,7 @@ public static function renderComponent($option, $params = array())
 			 * @since  1.5
 			 * @deprecated 5.0 without replacement
 			 */
-			define('JPATH_COMPONENT_ADMINISTRATOR', JPATH_ADMINISTRATOR . '/components/' . $option);
+			\define('JPATH_COMPONENT_ADMINISTRATOR', JPATH_ADMINISTRATOR . '/components/' . $option);
 		}
 
 		// If component is disabled throw error
@@ -464,7 +464,7 @@ public static function getComponentName($object, string $alternativeName): strin
 	{
 		$reflect = new \ReflectionClass($object);
 
-		if (!$reflect->getNamespaceName() || get_class($object) == ComponentDispatcher::class)
+		if (!$reflect->getNamespaceName() || \get_class($object) == ComponentDispatcher::class)
 		{
 			return 'com_' . strtolower($alternativeName);
 		}
diff --git a/libraries/src/Component/ComponentRecord.php b/libraries/src/Component/ComponentRecord.php
index 5aa0caafbe4ea..edef74f26a390 100644
--- a/libraries/src/Component/ComponentRecord.php
+++ b/libraries/src/Component/ComponentRecord.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Registry\Registry;
 
diff --git a/libraries/src/Component/Exception/MissingComponentException.php b/libraries/src/Component/Exception/MissingComponentException.php
index f7e7e5db05aa4..91a45a0272def 100644
--- a/libraries/src/Component/Exception/MissingComponentException.php
+++ b/libraries/src/Component/Exception/MissingComponentException.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Exception;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Router\Exception\RouteNotFoundException;
 
diff --git a/libraries/src/Component/Router/RouterBase.php b/libraries/src/Component/Router/RouterBase.php
index 0ed72c9ca4ae3..b8247963b6441 100644
--- a/libraries/src/Component/Router/RouterBase.php
+++ b/libraries/src/Component/Router/RouterBase.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Factory;
 
diff --git a/libraries/src/Component/Router/RouterFactory.php b/libraries/src/Component/Router/RouterFactory.php
index faf59a4bcf93c..7485ce0aae729 100644
--- a/libraries/src/Component/Router/RouterFactory.php
+++ b/libraries/src/Component/Router/RouterFactory.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router;
 
-defined('_JEXEC') or die;
+\defined('_JEXEC') or die;
 
 use Joomla\CMS\Application\CMSApplicationInterface;
 use Joomla\CMS\Categories\CategoryFactoryInterface;
diff --git a/libraries/src/Component/Router/RouterFactoryInterface.php b/libraries/src/Component/Router/RouterFactoryInterface.php
index e01cf0ceb1f84..2ca92902a160e 100644
--- a/libraries/src/Component/Router/RouterFactoryInterface.php
+++ b/libraries/src/Component/Router/RouterFactoryInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router;
 
-defined('_JEXEC') or die;
+\defined('_JEXEC') or die;
 
 use Joomla\CMS\Application\CMSApplicationInterface;
 use Joomla\CMS\Menu\AbstractMenu;
diff --git a/libraries/src/Component/Router/RouterInterface.php b/libraries/src/Component/Router/RouterInterface.php
index 893de8e22e411..e8cc41ce4746d 100644
--- a/libraries/src/Component/Router/RouterInterface.php
+++ b/libraries/src/Component/Router/RouterInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Component routing interface
diff --git a/libraries/src/Component/Router/RouterLegacy.php b/libraries/src/Component/Router/RouterLegacy.php
index 33e1225629d86..8f9647ddf5ea2 100644
--- a/libraries/src/Component/Router/RouterLegacy.php
+++ b/libraries/src/Component/Router/RouterLegacy.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Default routing class for missing or legacy component routers
@@ -64,10 +64,10 @@ public function build(&$query)
 	{
 		$function = $this->component . 'BuildRoute';
 
-		if (function_exists($function))
+		if (\function_exists($function))
 		{
 			$segments = $function($query);
-			$total    = count($segments);
+			$total    = \count($segments);
 
 			for ($i = 0; $i < $total; $i++)
 			{
@@ -93,9 +93,9 @@ public function parse(&$segments)
 	{
 		$function = $this->component . 'ParseRoute';
 
-		if (function_exists($function))
+		if (\function_exists($function))
 		{
-			$total = count($segments);
+			$total = \count($segments);
 
 			for ($i = 0; $i < $total; $i++)
 			{
diff --git a/libraries/src/Component/Router/RouterServiceInterface.php b/libraries/src/Component/Router/RouterServiceInterface.php
index d4469dbbfd406..1db67503dbf2e 100644
--- a/libraries/src/Component/Router/RouterServiceInterface.php
+++ b/libraries/src/Component/Router/RouterServiceInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Application\CMSApplicationInterface;
 use Joomla\CMS\Menu\AbstractMenu;
diff --git a/libraries/src/Component/Router/RouterServiceTrait.php b/libraries/src/Component/Router/RouterServiceTrait.php
index acb2f16585305..6cf04fe34ba7a 100644
--- a/libraries/src/Component/Router/RouterServiceTrait.php
+++ b/libraries/src/Component/Router/RouterServiceTrait.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Application\CMSApplicationInterface;
 use Joomla\CMS\Menu\AbstractMenu;
diff --git a/libraries/src/Component/Router/RouterView.php b/libraries/src/Component/Router/RouterView.php
index 808c9a4cfd15f..8862223ce8065 100644
--- a/libraries/src/Component/Router/RouterView.php
+++ b/libraries/src/Component/Router/RouterView.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Component\ComponentHelper;
 use Joomla\CMS\Component\Router\Rules\RulesInterface;
@@ -114,15 +114,15 @@ public function getPath($query)
 
 				$childkey = $view->parent_key;
 
-				if (($key || $view->key) && is_callable(array($this, 'get' . ucfirst($view->name) . 'Segment')))
+				if (($key || $view->key) && \is_callable(array($this, 'get' . ucfirst($view->name) . 'Segment')))
 				{
 					if (isset($query[$key]))
 					{
-						$result[$view->name] = call_user_func_array(array($this, 'get' . ucfirst($view->name) . 'Segment'), array($query[$key], $query));
+						$result[$view->name] = \call_user_func_array(array($this, 'get' . ucfirst($view->name) . 'Segment'), array($query[$key], $query));
 					}
 					elseif (isset($query[$view->key]))
 					{
-						$result[$view->name] = call_user_func_array(array($this, 'get' . ucfirst($view->name) . 'Segment'), array($query[$view->key], $query));
+						$result[$view->name] = \call_user_func_array(array($this, 'get' . ucfirst($view->name) . 'Segment'), array($query[$view->key], $query));
 					}
 					else
 					{
@@ -283,7 +283,7 @@ public function getName()
 		{
 			$r = null;
 
-			if (!preg_match('/(.*)Router/i', get_class($this), $r))
+			if (!preg_match('/(.*)Router/i', \get_class($this), $r))
 			{
 				throw new \Exception('JLIB_APPLICATION_ERROR_ROUTER_GET_NAME', 500);
 			}
diff --git a/libraries/src/Component/Router/RouterViewConfiguration.php b/libraries/src/Component/Router/RouterViewConfiguration.php
index e2cacf1feca62..92d13740ffe57 100644
--- a/libraries/src/Component/Router/RouterViewConfiguration.php
+++ b/libraries/src/Component/Router/RouterViewConfiguration.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * View-configuration class for the view-based component router
diff --git a/libraries/src/Component/Router/Rules/MenuRules.php b/libraries/src/Component/Router/Rules/MenuRules.php
index 2622fae4aaa79..c676cee7f5982 100644
--- a/libraries/src/Component/Router/Rules/MenuRules.php
+++ b/libraries/src/Component/Router/Rules/MenuRules.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router\Rules;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Component\ComponentHelper;
 use Joomla\CMS\Component\Router\RouterView;
@@ -98,7 +98,7 @@ public function preprocess(&$query)
 				if (isset($query[$k]) && $v !== $query[$k])
 				{
 					// Compare again without alias
-					if (is_string($v) && $v == current(explode(':', $query[$k], 2)))
+					if (\is_string($v) && $v == current(explode(':', $query[$k], 2)))
 					{
 						continue;
 					}
@@ -127,7 +127,7 @@ public function preprocess(&$query)
 
 				if ($layout && isset($this->lookup[$language][$viewLayout]))
 				{
-					if (is_bool($ids))
+					if (\is_bool($ids))
 					{
 						$query['Itemid'] = $this->lookup[$language][$viewLayout];
 
@@ -147,7 +147,7 @@ public function preprocess(&$query)
 
 				if (isset($this->lookup[$language][$view]))
 				{
-					if (is_bool($ids))
+					if (\is_bool($ids))
 					{
 						$query['Itemid'] = $this->lookup[$language][$view];
 
@@ -169,7 +169,7 @@ public function preprocess(&$query)
 
 		// Check if the active menuitem matches the requested language
 		if ($active && $active->component === 'com_' . $this->router->getName()
-			&& ($language === '*' || in_array($active->language, array('*', $language)) || !Multilanguage::isEnabled()))
+			&& ($language === '*' || \in_array($active->language, array('*', $language)) || !Multilanguage::isEnabled()))
 		{
 			$query['Itemid'] = $active->id;
 
diff --git a/libraries/src/Component/Router/Rules/NomenuRules.php b/libraries/src/Component/Router/Rules/NomenuRules.php
index 0f76012a5cda6..cd0d1ead754fb 100644
--- a/libraries/src/Component/Router/Rules/NomenuRules.php
+++ b/libraries/src/Component/Router/Rules/NomenuRules.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router\Rules;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Component\Router\RouterView;
 
@@ -67,7 +67,7 @@ public function parse(&$segments, &$vars)
 	{
 		$active = $this->router->menu->getActive();
 
-		if (!is_object($active))
+		if (!\is_object($active))
 		{
 			$views = $this->router->getViews();
 
@@ -118,9 +118,9 @@ public function build(&$query, &$segments)
 
 				if ($view->key && isset($query[$view->key]))
 				{
-					if (is_callable(array($this->router, 'get' . ucfirst($view->name) . 'Segment')))
+					if (\is_callable(array($this->router, 'get' . ucfirst($view->name) . 'Segment')))
 					{
-						$result = call_user_func_array(array($this->router, 'get' . ucfirst($view->name) . 'Segment'), array($query[$view->key], $query));
+						$result = \call_user_func_array(array($this->router, 'get' . ucfirst($view->name) . 'Segment'), array($query[$view->key], $query));
 						$segments[] = str_replace(':', '-', array_shift($result));
 					}
 					else
diff --git a/libraries/src/Component/Router/Rules/RulesInterface.php b/libraries/src/Component/Router/Rules/RulesInterface.php
index a520bd487d0de..278cf29381f25 100644
--- a/libraries/src/Component/Router/Rules/RulesInterface.php
+++ b/libraries/src/Component/Router/Rules/RulesInterface.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router\Rules;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * RouterRules interface for Joomla
diff --git a/libraries/src/Component/Router/Rules/StandardRules.php b/libraries/src/Component/Router/Rules/StandardRules.php
index a4043f6058ea4..d2bcbb0e9eefb 100644
--- a/libraries/src/Component/Router/Rules/StandardRules.php
+++ b/libraries/src/Component/Router/Rules/StandardRules.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Component\Router\Rules;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Component\Router\RouterView;
 
@@ -88,9 +88,9 @@ public function parse(&$segments, &$vars)
 			// Our current view is nestable. We need to check first if the segment fits to that
 			if ($views[$vars['view']]->nestable)
 			{
-				if (is_callable(array($this->router, 'get' . ucfirst($views[$vars['view']]->name) . 'Id')))
+				if (\is_callable(array($this->router, 'get' . ucfirst($views[$vars['view']]->name) . 'Id')))
 				{
-					$key = call_user_func_array(array($this->router, 'get' . ucfirst($views[$vars['view']]->name) . 'Id'), array($segment, $vars));
+					$key = \call_user_func_array(array($this->router, 'get' . ucfirst($views[$vars['view']]->name) . 'Id'), array($segment, $vars));
 
 					// Did we get a proper key? If not, we need to look in the child-views
 					if ($key)
@@ -134,10 +134,10 @@ public function parse(&$segments, &$vars)
 						break;
 					}
 				}
-				elseif (is_callable(array($this->router, 'get' . ucfirst($view->name) . 'Id')))
+				elseif (\is_callable(array($this->router, 'get' . ucfirst($view->name) . 'Id')))
 				{
 					// Hand the data over to the router specific method and see if there is a content item that fits
-					$key = call_user_func_array(array($this->router, 'get' . ucfirst($view->name) . 'Id'), array($segment, $vars));
+					$key = \call_user_func_array(array($this->router, 'get' . ucfirst($view->name) . 'Id'), array($segment, $vars));
 
 					if ($key)
 					{
diff --git a/libraries/src/Console/CheckUpdatesCommand.php b/libraries/src/Console/CheckUpdatesCommand.php
index 4c0b4049ec23d..bfdaa1276299a 100644
--- a/libraries/src/Console/CheckUpdatesCommand.php
+++ b/libraries/src/Console/CheckUpdatesCommand.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Console;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Component\ComponentHelper;
 use Joomla\CMS\Updater\Updater;
diff --git a/libraries/src/Console/CleanCacheCommand.php b/libraries/src/Console/CleanCacheCommand.php
index cc78cc0dc5835..d5fb1909492cd 100644
--- a/libraries/src/Console/CleanCacheCommand.php
+++ b/libraries/src/Console/CleanCacheCommand.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Console;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Factory;
 use Joomla\Console\Command\AbstractCommand;
diff --git a/libraries/src/Console/Loader/WritableContainerLoader.php b/libraries/src/Console/Loader/WritableContainerLoader.php
index 7b723c86874b6..9a1b46ac46955 100644
--- a/libraries/src/Console/Loader/WritableContainerLoader.php
+++ b/libraries/src/Console/Loader/WritableContainerLoader.php
@@ -12,7 +12,7 @@
 use Psr\Container\ContainerInterface;
 use Symfony\Component\Console\Exception\CommandNotFoundException;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * PSR-11 compatible writable command loader.
diff --git a/libraries/src/Console/Loader/WritableLoaderInterface.php b/libraries/src/Console/Loader/WritableLoaderInterface.php
index 91f11dd139169..0bfe671a48281 100644
--- a/libraries/src/Console/Loader/WritableLoaderInterface.php
+++ b/libraries/src/Console/Loader/WritableLoaderInterface.php
@@ -10,7 +10,7 @@
 
 use Joomla\Console\Loader\LoaderInterface;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 /**
  * Interface defining a writable command loader.
diff --git a/libraries/src/Console/RemoveOldFilesCommand.php b/libraries/src/Console/RemoveOldFilesCommand.php
index d26b52d5f2643..8a15a91ee1310 100644
--- a/libraries/src/Console/RemoveOldFilesCommand.php
+++ b/libraries/src/Console/RemoveOldFilesCommand.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Console;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Console\Command\AbstractCommand;
 use Symfony\Component\Console\Input\InputInterface;
diff --git a/libraries/src/Console/SessionGcCommand.php b/libraries/src/Console/SessionGcCommand.php
index d27c7ee7672be..e93a36e859fb3 100644
--- a/libraries/src/Console/SessionGcCommand.php
+++ b/libraries/src/Console/SessionGcCommand.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Console;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Console\Command\AbstractCommand;
 use Joomla\DI\ContainerAwareInterface;
diff --git a/libraries/src/Console/SessionMetadataGcCommand.php b/libraries/src/Console/SessionMetadataGcCommand.php
index 0c9298c7f8f25..afcfd0ae6b268 100644
--- a/libraries/src/Console/SessionMetadataGcCommand.php
+++ b/libraries/src/Console/SessionMetadataGcCommand.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Console;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\CMS\Session\MetadataManager;
 use Joomla\Console\Command\AbstractCommand;
diff --git a/libraries/src/Crypt/Cipher/CryptoCipher.php b/libraries/src/Crypt/Cipher/CryptoCipher.php
index 5f038845af136..0ffd1299b6f3a 100644
--- a/libraries/src/Crypt/Cipher/CryptoCipher.php
+++ b/libraries/src/Crypt/Cipher/CryptoCipher.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Crypt\Cipher;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Crypt\CipherInterface;
 use Joomla\Crypt\Key;
diff --git a/libraries/src/Crypt/Cipher/SodiumCipher.php b/libraries/src/Crypt/Cipher/SodiumCipher.php
index 259d963319add..767154a42beab 100644
--- a/libraries/src/Crypt/Cipher/SodiumCipher.php
+++ b/libraries/src/Crypt/Cipher/SodiumCipher.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Crypt\Cipher;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Crypt\CipherInterface;
 use Joomla\Crypt\Key;
diff --git a/libraries/src/Crypt/Crypt.php b/libraries/src/Crypt/Crypt.php
index 7d02f4de0a80b..2327d3b5e15c5 100644
--- a/libraries/src/Crypt/Crypt.php
+++ b/libraries/src/Crypt/Crypt.php
@@ -8,7 +8,7 @@
 
 namespace Joomla\CMS\Crypt;
 
-defined('JPATH_PLATFORM') or die;
+\defined('JPATH_PLATFORM') or die;
 
 use Joomla\Crypt\Crypt as JCrypt;
 
@@ -57,7 +57,7 @@ public static function safeStrlen($str)
 
 		if ($exists === null)
 		{
-			$exists = function_exists('mb_strlen');
+			$exists = \function_exists('mb_strlen');
 		}
 
 		if ($exists)
@@ -95,7 +95,7 @@ public static function safeSubstr($str, $start, $length = null)
 
 		if ($exists === null)
 		{
-			$exists = function_exists('mb_substr');
+			$exists = \function_exists('mb_substr');
 		}
 
 		if ($exists)