diff --git a/lam/lib/pdf.inc b/lam/lib/pdf.inc
index 478317b3a..966de7ad6 100644
--- a/lam/lib/pdf.inc
+++ b/lam/lib/pdf.inc
@@ -228,7 +228,7 @@ function printTable(&$pdf, $table, $fontName) {
 	foreach ($table->rows as $row) {
 		foreach ($row->cells as $cell) {
 			$width = $cell->width;
-			if (!empty($width) && (strpos($width, '%') !== false)) {
+			if (!empty($width) && (str_contains($width, '%'))) {
 				$width = ceil(LAMPDF_LINEWIDTH * substr($width, 0, -1) / 100);
 			}
 			if ($cell->bold) {
@@ -336,9 +336,9 @@ class PDFTableRow {
  */
 class PDFTableCell {
 
-	const ALIGN_LEFT = 'L';
-	const ALIGN_RIGHT = 'R';
-	const ALIGN_CENTER = 'C';
+	public const ALIGN_LEFT = 'L';
+	public const ALIGN_RIGHT = 'R';
+	public const ALIGN_CENTER = 'C';
 
 	/** content text of cell */
 	public $content = '';
diff --git a/lam/lib/pdfstruct.inc b/lam/lib/pdfstruct.inc
index bbc04c5ad..42f073a42 100644
--- a/lam/lib/pdfstruct.inc
+++ b/lam/lib/pdfstruct.inc
@@ -723,7 +723,7 @@ class PdfStructurePersistenceStrategyFiles implements PdfStructurePersistenceStr
 		if ($templateDir) {
 			$entry = $templateDir->read();
 			while ($entry) {
-				if ((strpos($entry, '.') !== 0) && is_file($templatePath . '/' . $entry)) {
+				if ((!str_starts_with($entry, '.')) && is_file($templatePath . '/' . $entry)) {
 					$logos[] = $entry;
 				}
 				$entry = $templateDir->read();
@@ -945,10 +945,10 @@ class PdfStructurePersistenceStrategyFiles implements PdfStructurePersistenceStr
  */
 class PdfStructurePersistenceStrategyPdo implements PdfStructurePersistenceStrategy {
 
-	const TABLE_NAME = 'pdf_structures';
-	const TABLE_NAME_LOGOS = 'pdf_logos';
-	const TABLE_NAME_TEMPLATES = 'pdf_structures_templates';
-	const TABLE_NAME_TEMPLATES_LOGOS = 'pdf_logos_templates';
+	private const TABLE_NAME = 'pdf_structures';
+	private const TABLE_NAME_LOGOS = 'pdf_logos';
+	private const TABLE_NAME_TEMPLATES = 'pdf_structures_templates';
+	private const TABLE_NAME_TEMPLATES_LOGOS = 'pdf_logos_templates';
 
 	/**
 	 * @var PDO
@@ -1388,9 +1388,9 @@ class PDFStructureWriter {
 class PDFStructure {
 
 	/** no folding marks */
-	const FOLDING_NONE = 'no';
+	public const FOLDING_NONE = 'no';
 	/** standard folding marks */
-	const FOLDING_STANDARD = 'standard';
+	public const FOLDING_STANDARD = 'standard';
 
 	private $logo;
 
diff --git a/lam/templates/pdfedit/pdfpage.php b/lam/templates/pdfedit/pdfpage.php
index 78c331b09..0dc296860 100644
--- a/lam/templates/pdfedit/pdfpage.php
+++ b/lam/templates/pdfedit/pdfpage.php
@@ -263,7 +263,10 @@
 if (isset($_SESSION['currentPDFStructure'])) {
 	$foldingMarks = $_SESSION['currentPDFStructure']->getFoldingMarks();
 }
-$possibleFoldingMarks = [_('No') => 'no', _('Yes') => 'standard'];
+$possibleFoldingMarks = [
+    _('No') => PDFStructure::FOLDING_NONE,
+    _('Yes') => PDFStructure::FOLDING_STANDARD
+];
 $foldingMarksSelect = new htmlResponsiveSelect('foldingmarks', $possibleFoldingMarks, [$foldingMarks], _('Folding marks'));
 $foldingMarksSelect->setHasDescriptiveElements(true);
 $mainContent->add($foldingMarksSelect, 12);