diff --git a/typo3/sysext/linkvalidator/Classes/Linktype/ExternalLinktype.php b/typo3/sysext/linkvalidator/Classes/Linktype/ExternalLinktype.php
index a6b02614e10a11b9d956a3bcf392428246ee5fb4..1aa084cbe407e1b8744148a92a5bb52e73707b83 100644
--- a/typo3/sysext/linkvalidator/Classes/Linktype/ExternalLinktype.php
+++ b/typo3/sysext/linkvalidator/Classes/Linktype/ExternalLinktype.php
@@ -98,7 +98,7 @@ class ExternalLinktype extends AbstractLinktype
      */
     protected $errorParams = [];
 
-    public function __construct(RequestFactory $requestFactory = null)
+    public function __construct(?RequestFactory $requestFactory = null)
     {
         $this->requestFactory = $requestFactory ?: GeneralUtility::makeInstance(RequestFactory::class);
     }
diff --git a/typo3/sysext/linkvalidator/Classes/Report/LinkValidatorReport.php b/typo3/sysext/linkvalidator/Classes/Report/LinkValidatorReport.php
index 8b763969a81c58fc4db78c569a7e4030b55ae372..77bb3b68ddeda23c0a03017edb0b6948b83ecdf8 100644
--- a/typo3/sysext/linkvalidator/Classes/Report/LinkValidatorReport.php
+++ b/typo3/sysext/linkvalidator/Classes/Report/LinkValidatorReport.php
@@ -154,11 +154,11 @@ class LinkValidatorReport
     protected PageRenderer $pageRenderer;
 
     public function __construct(
-        PagesRepository $pagesRepository = null,
-        BrokenLinkRepository $brokenLinkRepository = null,
-        ModuleTemplateFactory $moduleTemplateFactory = null,
-        IconFactory $iconFactory = null,
-        PageRenderer $pageRecord = null
+        ?PagesRepository $pagesRepository = null,
+        ?BrokenLinkRepository $brokenLinkRepository = null,
+        ?ModuleTemplateFactory $moduleTemplateFactory = null,
+        ?IconFactory $iconFactory = null,
+        ?PageRenderer $pageRecord = null
     ) {
         $this->iconFactory = $iconFactory ?? GeneralUtility::makeInstance(IconFactory::class);
         $this->pagesRepository = $pagesRepository ?? GeneralUtility::makeInstance(PagesRepository::class);
diff --git a/typo3/sysext/linkvalidator/Classes/Repository/BrokenLinkRepository.php b/typo3/sysext/linkvalidator/Classes/Repository/BrokenLinkRepository.php
index e1dcdb929ec731dfef93b48b191f55f13de22fdd..4217e5d250e7e44dcffae67953515b66f8e37e01 100644
--- a/typo3/sysext/linkvalidator/Classes/Repository/BrokenLinkRepository.php
+++ b/typo3/sysext/linkvalidator/Classes/Repository/BrokenLinkRepository.php
@@ -327,7 +327,7 @@ class BrokenLinkRepository
      * @throws \UnexpectedValueException
      * @todo Make default value of $errorParams [] instead of null and add strict typing in v13
      */
-    public function addBrokenLink($record, bool $isValid, array $errorParams = null): void
+    public function addBrokenLink($record, bool $isValid, ?array $errorParams = null): void
     {
         $response = ['valid' => $isValid];
         $response['errorParams'] = $errorParams ?? [];