diff --git a/Classes/Domain/Model/DataAttribute.php b/Classes/Domain/Model/DataAttribute.php
index 791f998..7943941 100644
--- a/Classes/Domain/Model/DataAttribute.php
+++ b/Classes/Domain/Model/DataAttribute.php
@@ -125,7 +125,7 @@ protected function ensureValue($value){
     /**
      * @return string
      */
-    public function getName()
+    public function getName() :string
     {
         if(substr($this->name, 0, 5) !== 'data-') {
             return self::NAME_PREFIX . $this->name;
@@ -137,7 +137,7 @@ public function getName()
     /**
      * @param string $name
      */
-    public function setName($name)
+    public function setName(string $name)
     {
         $this->ensureName($name);
     }
@@ -145,7 +145,7 @@ public function setName($name)
     /**
      * @return string
      */
-    public function getValue()
+    public function getValue() :string
     {
         return $this->value;
     }
@@ -153,7 +153,7 @@ public function getValue()
     /**
      * @param string $value
      */
-    public function setValue($value)
+    public function setValue(string $value)
     {
         $this->ensureValue($value);
     }
diff --git a/Classes/Domain/Model/Iframe.php b/Classes/Domain/Model/Iframe.php
index f511e93..52b9248 100644
--- a/Classes/Domain/Model/Iframe.php
+++ b/Classes/Domain/Model/Iframe.php
@@ -252,7 +252,7 @@ protected function ensureDataAttributes($definition) {
     /**
      * @return string
      */
-    public function getSrc()
+    public function getSrc() :string
     {
         return $this->src;
     }
@@ -261,7 +261,7 @@ public function getSrc()
      * @param string $src
      * @return void
      */
-    public function setSrc($src)
+    public function setSrc(string $src)
     {
         $this->ensureSrc($src);
     }
@@ -269,7 +269,7 @@ public function setSrc($src)
     /**
      * @return string
      */
-    public function getClass()
+    public function getClass() :string
     {
         return $this->class;
     }
@@ -277,7 +277,7 @@ public function getClass()
     /**
      * @param string $class
      */
-    public function setClass($class)
+    public function setClass(string $class)
     {
         $this->class = $class;
     }
@@ -285,7 +285,7 @@ public function setClass($class)
     /**
      * @return string
      */
-    public function getName()
+    public function getName() :string
     {
         return $this->name;
     }
@@ -293,7 +293,7 @@ public function getName()
     /**
      * @param string $name
      */
-    public function setName($name)
+    public function setName(string $name)
     {
         $this->name = $name;
     }
@@ -301,7 +301,7 @@ public function setName($name)
     /**
      * @return int
      */
-    public function getWidth()
+    public function getWidth() :int
     {
         return $this->width;
     }
@@ -310,7 +310,7 @@ public function getWidth()
      * @param int $width
      * @return void
      */
-    public function setWidth($width)
+    public function setWidth(int $width)
     {
         $this->ensureWidth($width);
     }
@@ -318,7 +318,7 @@ public function setWidth($width)
     /**
      * @return int
      */
-    public function getHeight()
+    public function getHeight() :int
     {
         return $this->height;
     }
@@ -326,7 +326,7 @@ public function getHeight()
     /**
      * @param int $height
      */
-    public function setHeight($height)
+    public function setHeight(int $height)
     {
         $this->ensureHeight($height);
     }
@@ -334,7 +334,7 @@ public function setHeight($height)
     /**
      * @return array
      */
-    public function getSandbox()
+    public function getSandbox() :array
     {
         return $this->sandbox;
     }
@@ -342,7 +342,7 @@ public function getSandbox()
     /**
      * @param string $sandbox
      */
-    public function setSandbox($sandbox)
+    public function setSandbox(string $sandbox)
     {
         $this->ensureSandboxValues($sandbox);
     }
@@ -350,7 +350,7 @@ public function setSandbox($sandbox)
     /**
      * @return boolean
      */
-    public function isAllowFullScreen()
+    public function isAllowFullScreen() :bool
     {
         return $this->allowFullScreen;
     }
@@ -358,15 +358,15 @@ public function isAllowFullScreen()
     /**
      * @param boolean $allowFullScreen
      */
-    public function setAllowFullScreen($allowFullScreen)
+    public function setAllowFullScreen(bool $allowFullScreen)
     {
-        $this->ensureAllowFullScreen(boolval($allowFullScreen));
+        $this->ensureAllowFullScreen($allowFullScreen);
     }
 
     /**
      * @return boolean
      */
-    public function isAllowPaymentRequest()
+    public function isAllowPaymentRequest() :bool
     {
         return $this->allowPaymentRequest;
     }
@@ -374,15 +374,15 @@ public function isAllowPaymentRequest()
     /**
      * @param boolean $allowPaymentRequest
      */
-    public function setAllowPaymentRequest($allowPaymentRequest)
+    public function setAllowPaymentRequest(bool $allowPaymentRequest)
     {
-        $this->ensureAllowPaymentRequest(boolval($allowPaymentRequest));
+        $this->ensureAllowPaymentRequest($allowPaymentRequest);
     }
 
     /**
      * @return array
      */
-    public function getDataAttributes()
+    public function getDataAttributes() :array
     {
         return $this->dataAttributes;
     }
@@ -390,7 +390,7 @@ public function getDataAttributes()
     /**
      * @param string $dataAttributes
      */
-    public function setDataAttributes($dataAttributes)
+    public function setDataAttributes(string $dataAttributes)
     {
         $this->ensureDataAttributes($dataAttributes);
     }
@@ -401,7 +401,7 @@ public function setDataAttributes($dataAttributes)
      * @return string
      * @throws InvalidValueException
      */
-    public function generateHtmlTag(){
+    public function generateHtmlTag() {
         $attributes = [];
         if($this->getSrc()) {
             $attributes['src'] = $this->getSrc();
diff --git a/Classes/Hooks/TypoScriptFrontendControllerHook.php b/Classes/Hooks/TypoScriptFrontendControllerHook.php
index 9f429d4..55effac 100644
--- a/Classes/Hooks/TypoScriptFrontendControllerHook.php
+++ b/Classes/Hooks/TypoScriptFrontendControllerHook.php
@@ -31,9 +31,7 @@ public function contentPostProcAll($pObjArray)
         if(isset($pObjArray['pObj'])) {
             /** @var TypoScriptFrontendController $typoScriptFrontendController */
             $typoScriptFrontendController = $pObjArray['pObj'];
-            $enabled = isset($typoScriptFrontendController->config['config']['csp.']['enabled'])
-                ? boolval($typoScriptFrontendController->config['config']['csp.']['enabled'])
-                : false;
+            $enabled = boolval($typoScriptFrontendController->config['config']['csp.']['enabled'] ?? false);
 
             if($enabled) {
 
diff --git a/Classes/Service/ContentSecurityPolicyManager.php b/Classes/Service/ContentSecurityPolicyManager.php
index e28433d..634f5f4 100644
--- a/Classes/Service/ContentSecurityPolicyManager.php
+++ b/Classes/Service/ContentSecurityPolicyManager.php
@@ -118,9 +118,8 @@ static public function isNonceModeEnabled() {
      * @throws InvalidClassException
      */
     static private function createNewBuilderInstance() {
-        $className = isset($GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['csp']['ContentSecurityPolicyHeaderBuilder'])
-            ? $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['csp']['ContentSecurityPolicyHeaderBuilder']
-            : ContentSecurityPolicyHeaderBuilder::class;
+        $className = $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['csp']['ContentSecurityPolicyHeaderBuilder'] ??
+            ContentSecurityPolicyHeaderBuilder::class;
 
         /** @var ContentSecurityPolicyHeaderBuilderInterface $instance */
         $instance = GeneralUtility::makeInstance($className);
@@ -161,9 +160,7 @@ static public function reloadConfig() {
      */
     static public function addTypoScriptSettings($tsfe) {
 
-        $enabled = isset($tsfe->config['config']['csp.']['enabled'])
-            ? boolval($tsfe->config['config']['csp.']['enabled'])
-            : false;
+        $enabled = boolval($tsfe->config['config']['csp.']['enabled'] ?? false);
 
         if($enabled) {
 
@@ -182,7 +179,7 @@ static public function addTypoScriptSettings($tsfe) {
                 && is_array($config['presets.'])) {
 
                 foreach ($config['presets.'] as $preSet) {
-                    $preSetEnabled = isset($preSet['enabled']) ? boolval($preSet['enabled']) : false;
+                    $preSetEnabled = boolval($preSet['enabled'] ?? false);
                     if ($preSetEnabled
                         && isset($preSet['rules.'])
                     ) {
@@ -203,8 +200,8 @@ static public function extractHeaders() {
         $responseHeader = '';
         $headers = self::getBuilder()->getHeader();
         if(count($headers) > 1) {
-            $name = isset($headers['name']) ? $headers['name'] : '';
-            $value = isset($headers['value']) ? $headers['value'] : '';;
+            $name = $headers['name'] ?? '';
+            $value = $headers['value'] ?? '';
 
             $responseHeader = $name . ': ' . $value;
         }
diff --git a/Classes/Utility/IframeUtility.php b/Classes/Utility/IframeUtility.php
index 0ebad76..5cccbbc 100644
--- a/Classes/Utility/IframeUtility.php
+++ b/Classes/Utility/IframeUtility.php
@@ -45,15 +45,15 @@ class IframeUtility
      * @return string
      */
     static public function generateIframeTagFromConfigArray($conf){
-        $src = isset($conf['src']) ? $conf['src'] : '';
-        $class = isset($conf['class']) ? $conf['class'] : '';
-        $name = isset($conf['name']) ? $conf['name'] : '';
-        $width = isset($conf['width']) ? $conf['width'] : 0;
-        $height = isset($conf['height']) ? $conf['height'] : 0;
-        $sandbox = isset($conf['sandbox']) ? $conf['sandbox'] : '';
-        $allowFullScreen = isset($conf['allowFullScreen']) ? $conf['allowFullScreen'] : '';
-        $allowPaymentRequest = isset($conf['allowPaymentRequest']) ? $conf['allowPaymentRequest'] : '';
-        $dataAttributes = isset($conf['dataAttributes']) ? $conf['dataAttributes'] : '';
+        $src = $conf['src'] ?? '';
+        $class = $conf['class'] ?? '';
+        $name = $conf['name'] ?? '';
+        $width = $conf['width'] ?? 0;
+        $height = $conf['height'] ?? 0;
+        $sandbox = $conf['sandbox'] ?? '';
+        $allowFullScreen = $conf['allowFullScreen'] ?? '';
+        $allowPaymentRequest = $conf['allowPaymentRequest'] ?? '';
+        $dataAttributes = $conf['dataAttributes'] ??  '';
 
 
         $iframe = new Iframe($src, $class, $name, $width, $height, $sandbox, $allowFullScreen, $allowPaymentRequest, $dataAttributes);
diff --git a/Classes/ViewHelpers/ScriptViewHelper.php b/Classes/ViewHelpers/ScriptViewHelper.php
index 7a4811e..2d39257 100644
--- a/Classes/ViewHelpers/ScriptViewHelper.php
+++ b/Classes/ViewHelpers/ScriptViewHelper.php
@@ -80,7 +80,7 @@ public function render($hashMethod = 'sha256')
     public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
     {
         $output = $renderChildrenClosure();
-        $hashMethod = isset($arguments['hashMethod']) ? $arguments['hashMethod'] : '';
+        $hashMethod = $arguments['hashMethod'] ?? '';
 
         if($hashMethod) {
             $output = ScriptUtility::getValidScriptTag($output, $hashMethod, true);