diff --git a/controllers/grid/files/form/LibraryFileForm.php b/controllers/grid/files/form/LibraryFileForm.php
index dd3b13f3907..d5d809ecd5b 100644
--- a/controllers/grid/files/form/LibraryFileForm.php
+++ b/controllers/grid/files/form/LibraryFileForm.php
@@ -22,8 +22,8 @@
 
 class LibraryFileForm extends Form
 {
-    /** @var LibraryFileManager the library file manager instantiated in this form. */
-    public $libraryFileManager;
+    /** the library file manager instantiated in this form. */
+    public LibraryFileManager $libraryFileManager;
 
     /**
      * Constructor.
@@ -56,7 +56,7 @@ function ($type) use ($libraryFileManager) {
      *
      * @param null|mixed $template
      */
-    public function fetch($request, $template = null, $display = false)
+    public function fetch($request, $template = null, $display = false): ?string
     {
         // load the file types for the selector on the form.
         $templateMgr = TemplateManager::getManager($request);
@@ -71,7 +71,7 @@ public function fetch($request, $template = null, $display = false)
      *
      * @see Form::readInputData()
      */
-    public function readInputData()
+    public function readInputData(): void
     {
         $this->readUserVars(['libraryFileName', 'fileType', 'publicAccess']);
     }
diff --git a/controllers/grid/settings/library/form/EditLibraryFileForm.php b/controllers/grid/settings/library/form/EditLibraryFileForm.php
index 35cef93e835..785d75dc2c0 100644
--- a/controllers/grid/settings/library/form/EditLibraryFileForm.php
+++ b/controllers/grid/settings/library/form/EditLibraryFileForm.php
@@ -26,16 +26,12 @@
 
 class EditLibraryFileForm extends LibraryFileForm
 {
-    /** @var LibraryFile the file being edited, or null for new */
-    public $libraryFile;
-
-    /** @var int the id of the context this library file is attached to */
-    public $contextId;
+    /** The file being edited, or null for new */
+    public ?LibraryFile $libraryFile;
 
     /**
      * Constructor.
      *
-     * @param int $contextId
      * @param int $fileId optional
      */
     public function __construct(int $contextId, $fileId)
@@ -54,16 +50,16 @@ public function __construct(int $contextId, $fileId)
      *
      * @see Form::readInputData()
      */
-    public function readInputData()
+    public function readInputData(): void
     {
         $this->readUserVars(['temporaryFileId']);
-        return parent::readInputData();
+        parent::readInputData();
     }
 
     /**
      * Initialize form data from current settings.
      */
-    public function initData()
+    public function initData(): void
     {
         $this->_data = [
             'libraryFileName' => $this->libraryFile->getName(null), // Localized
@@ -81,13 +77,13 @@ public function execute(...$functionArgs)
         $userId = Application::get()->getRequest()->getUser()->getId();
 
         // Fetch the temporary file storing the uploaded library file
-        $temporaryFileDao = DAORegistry::getDAO('TemporaryFileDAO'); /* @var $temporaryFileDao TemporaryFileDAO */
+        $temporaryFileDao = DAORegistry::getDAO('TemporaryFileDAO'); /* @var \PKP\file\TemporaryFileDAO $temporaryFileDao*/
         $temporaryFile = $temporaryFileDao->getTemporaryFile(
             $this->getData('temporaryFileId'),
             $userId
         );
         if ($temporaryFile) {
-            $libraryFileDao = DAORegistry::getDAO('LibraryFileDAO'); /* @var $libraryFileDao LibraryFileDAO */
+            $libraryFileDao = DAORegistry::getDAO('LibraryFileDAO'); /* @var LibraryFileDAO $libraryFileDao */
             $libraryFileManager = new LibraryFileManager($this->contextId);
 
             // Convert the temporary file to a library file and store