diff --git a/typo3/sysext/workspaces/Classes/Controller/ReviewController.php b/typo3/sysext/workspaces/Classes/Controller/ReviewController.php
index 1a230043720517ff75bdf0740e54ed166cc18dd7..4e430362c0485535b7b2227732f31fb6c9301498 100644
--- a/typo3/sysext/workspaces/Classes/Controller/ReviewController.php
+++ b/typo3/sysext/workspaces/Classes/Controller/ReviewController.php
@@ -280,7 +280,7 @@ class ReviewController
      * @param int $workspaceId
      * @return string
      */
-    protected function getModuleUri(int $workspaceId = null): string
+    protected function getModuleUri(?int $workspaceId = null): string
     {
         $parameters = [
             'id' => $this->pageId,
diff --git a/typo3/sysext/workspaces/Classes/Domain/Model/DatabaseRecord.php b/typo3/sysext/workspaces/Classes/Domain/Model/DatabaseRecord.php
index aa5ae23f8fe0007915c26d5e6f05f930ce58e499..b53049ecaa961064ee96f34c02db7bb07301e294 100644
--- a/typo3/sysext/workspaces/Classes/Domain/Model/DatabaseRecord.php
+++ b/typo3/sysext/workspaces/Classes/Domain/Model/DatabaseRecord.php
@@ -67,7 +67,7 @@ class DatabaseRecord
      * @param int $uid Id of the database record row
      * @param array|null $row The relevant database record row
      */
-    public function __construct($table, $uid, array $row = null)
+    public function __construct($table, $uid, ?array $row = null)
     {
         $this->setTable($table);
         $this->setUid($uid);
diff --git a/typo3/sysext/workspaces/Classes/Domain/Record/StageRecord.php b/typo3/sysext/workspaces/Classes/Domain/Record/StageRecord.php
index 55b989e7f6acea22ccd0a5e68a262db0ef979d9b..807379a934facfd2c9df574473e99f9747c7e749 100644
--- a/typo3/sysext/workspaces/Classes/Domain/Record/StageRecord.php
+++ b/typo3/sysext/workspaces/Classes/Domain/Record/StageRecord.php
@@ -57,7 +57,7 @@ class StageRecord extends AbstractRecord
      * @param array $record
      * @return StageRecord|null
      */
-    public static function get($uid, array $record = null)
+    public static function get($uid, ?array $record = null)
     {
         if (empty($record)) {
             $record = static::fetch('sys_workspace_stage', $uid);
@@ -71,7 +71,7 @@ class StageRecord extends AbstractRecord
      * @param array $record
      * @return StageRecord
      */
-    public static function build(WorkspaceRecord $workspace, $uid, array $record = null)
+    public static function build(WorkspaceRecord $workspace, $uid, ?array $record = null)
     {
         if (empty($record)) {
             $record = static::fetch('sys_workspace_stage', $uid);
diff --git a/typo3/sysext/workspaces/Classes/Domain/Record/WorkspaceRecord.php b/typo3/sysext/workspaces/Classes/Domain/Record/WorkspaceRecord.php
index 9f76f3beb79427048343c50b43aaffb038076e4c..8c19dbe2afa2f5f653c6512422f4a8f25e7ac769 100644
--- a/typo3/sysext/workspaces/Classes/Domain/Record/WorkspaceRecord.php
+++ b/typo3/sysext/workspaces/Classes/Domain/Record/WorkspaceRecord.php
@@ -72,7 +72,7 @@ class WorkspaceRecord extends AbstractRecord
      * @param array $record
      * @return WorkspaceRecord
      */
-    public static function get($uid, array $record = null)
+    public static function get($uid, ?array $record = null)
     {
         if (empty($uid)) {
             $record = [];
diff --git a/typo3/sysext/workspaces/Classes/Middleware/WorkspacePreview.php b/typo3/sysext/workspaces/Classes/Middleware/WorkspacePreview.php
index 22ecb45d0c0b1718221404aa15388a7ace6b0b1b..47032255fc364f1cb70ade89dfd7feffff09f303 100644
--- a/typo3/sysext/workspaces/Classes/Middleware/WorkspacePreview.php
+++ b/typo3/sysext/workspaces/Classes/Middleware/WorkspacePreview.php
@@ -413,7 +413,7 @@ class WorkspacePreview implements MiddlewareInterface
     /**
      * Register or override the backend user as aspect, as well as the workspace information the user object is holding
      */
-    protected function setBackendUserAspect(Context $context, BackendUserAuthentication $user = null)
+    protected function setBackendUserAspect(Context $context, ?BackendUserAuthentication $user = null)
     {
         $context->setAspect('backend.user', GeneralUtility::makeInstance(UserAspect::class, $user));
         $context->setAspect('workspace', GeneralUtility::makeInstance(WorkspaceAspect::class, $user ? $user->workspace : 0));
diff --git a/typo3/sysext/workspaces/Classes/Preview/PreviewUriBuilder.php b/typo3/sysext/workspaces/Classes/Preview/PreviewUriBuilder.php
index 1b32c33f38f9f192c7060e4fe7376afeb528300b..0546d589ee8e17c86fa7b897432950e699447114 100644
--- a/typo3/sysext/workspaces/Classes/Preview/PreviewUriBuilder.php
+++ b/typo3/sysext/workspaces/Classes/Preview/PreviewUriBuilder.php
@@ -148,7 +148,7 @@ class PreviewUriBuilder
      * @param array $versionRecord Optional version record data
      * @return string
      */
-    public function buildUriForElement(string $table, int $uid, array $liveRecord = null, array $versionRecord = null): string
+    public function buildUriForElement(string $table, int $uid, ?array $liveRecord = null, ?array $versionRecord = null): string
     {
         $previewUri = $this->createPreviewUriForElement($table, $uid, $liveRecord, $versionRecord);
         $event = new RetrievedPreviewUrlEvent($table, $uid, $previewUri, [
@@ -161,7 +161,7 @@ class PreviewUriBuilder
         return $previewUri;
     }
 
-    protected function createPreviewUriForElement(string $table, int $uid, array $liveRecord = null, array $versionRecord = null): ?UriInterface
+    protected function createPreviewUriForElement(string $table, int $uid, ?array $liveRecord = null, ?array $versionRecord = null): ?UriInterface
     {
         if ($table === 'pages') {
             return BackendPreviewUriBuilder::create((int)BackendUtility::getLiveVersionIdOfRecord('pages', $uid))
@@ -221,7 +221,7 @@ class PreviewUriBuilder
      * @param int|null $workspaceId Which workspace ID to preview.
      * @return string Returns keyword to use in URL for ADMCMD_prev=, a 32 byte MD5 hash keyword for the URL: "?ADMCMD_prev=[keyword]
      */
-    protected function compilePreviewKeyword(int $ttl = 172800, int $workspaceId = null): string
+    protected function compilePreviewKeyword(int $ttl = 172800, ?int $workspaceId = null): string
     {
         $keyword = md5(StringUtility::getUniqueId());
         GeneralUtility::makeInstance(ConnectionPool::class)