diff --git a/dca/tl_catalog.php b/dca/tl_catalog.php
index daee0b1f..96075d6e 100644
--- a/dca/tl_catalog.php
+++ b/dca/tl_catalog.php
@@ -53,7 +53,7 @@
                 'label' => &$GLOBALS['TL_LANG']['tl_catalog']['delete'],
                 'href' => 'act=delete',
                 'icon' => 'delete.gif',
-                'attributes' => 'onclick="if(!confirm(\'' . ($GLOBALS['TL_LANG']['MSC']['deleteConfirm'] ?? '') . '\'))return false;Backend.getScrollOffset()"'
+                'attributes' => 'onclick="if(!confirm(\'' . ($GLOBALS['TL_LANG']['MSC']['deleteConfirm']??'') . '\'))return false;Backend.getScrollOffset()"'
             ],
             'show' => [
                 'label' => &$GLOBALS['TL_LANG']['tl_catalog']['show'],
@@ -1024,4 +1024,4 @@
             'sql' => "varchar(255) NOT NULL default ''"
         ],
     ]
-];
\ No newline at end of file
+];
diff --git a/dca/tl_catalog_fields.php b/dca/tl_catalog_fields.php
index 474eed1b..63cd4b4a 100644
--- a/dca/tl_catalog_fields.php
+++ b/dca/tl_catalog_fields.php
@@ -1881,4 +1881,4 @@
             'sql' => "varchar(255) NOT NULL default ''"
         ]
     ]
-];
\ No newline at end of file
+];
diff --git a/dca/tl_catalog_form.php b/dca/tl_catalog_form.php
index 01406c9b..12b3eaa6 100644
--- a/dca/tl_catalog_form.php
+++ b/dca/tl_catalog_form.php
@@ -305,4 +305,4 @@
             'sql' => "varchar(16) NOT NULL default ''"
         ]
     ]
-];
\ No newline at end of file
+];
diff --git a/dca/tl_catalog_form_fields.php b/dca/tl_catalog_form_fields.php
index a8ce491e..492de5ef 100644
--- a/dca/tl_catalog_form_fields.php
+++ b/dca/tl_catalog_form_fields.php
@@ -762,4 +762,4 @@
             'sql' => "char(1) NOT NULL default ''"
         ]
     ]
-];
\ No newline at end of file
+];
diff --git a/library/alnv/CatalogDcExtractor.php b/library/alnv/CatalogDcExtractor.php
index a23cd28a..02d7b2df 100644
--- a/library/alnv/CatalogDcExtractor.php
+++ b/library/alnv/CatalogDcExtractor.php
@@ -290,17 +290,17 @@ protected function extractDCASorting($arrSorting)
     protected function convertDcConfigToCatalog($arrReturn, $arrDataContainer, $strDcConfigType)
     {
 
-        if ($arrDataContainer[$strDcConfigType]['enableVersioning']) {
+        if ($arrDataContainer[$strDcConfigType]['enableVersioning'] ?? null) {
 
             $arrReturn['useVC'] = $arrDataContainer['config']['enableVersioning'] ? '1' : '';
         }
 
-        if ($arrDataContainer[$strDcConfigType]['ptable']) {
+        if ($arrDataContainer[$strDcConfigType]['ptable'] ?? null) {
 
             $arrReturn['pTable'] = $arrDataContainer['config']['ptable'];
         }
 
-        if (is_array($arrDataContainer[$strDcConfigType]['ctable']) && !empty($arrDataContainer['config']['ctable'])) {
+        if (is_array($arrDataContainer[$strDcConfigType]['ctable'] ?? null) && !empty($arrDataContainer['config']['ctable'])) {
 
             if (in_array('tl_content', $arrDataContainer[$strDcConfigType]['ctable'])) {
 
@@ -335,7 +335,7 @@ protected function convertDcSortingToCatalog($arrReturn, $arrDataContainer, $str
                 $arrReturn['panelLayout'] = serialize($arrPanelLayout);
             }
 
-            if (is_array($arrDataContainer[$strDcConfigType]['sorting']['fields']) && !empty($arrDataContainer[$strDcConfigType]['sorting']['fields'])) {
+            if (is_array($arrDataContainer[$strDcConfigType]['sorting']['fields'] ?? null) && !empty($arrDataContainer[$strDcConfigType]['sorting']['fields'])) {
 
                 $arrFields = [];
                 $arrSortingFields = $arrDataContainer[$strDcConfigType]['sorting']['fields'];
@@ -362,7 +362,7 @@ protected function convertDcSortingToCatalog($arrReturn, $arrDataContainer, $str
                 $arrReturn['sortingFields'] = serialize($arrFields);
             }
 
-            if (is_array($arrDataContainer[$strDcConfigType]['sorting']['headerFields']) && !empty($arrDataContainer[$strDcConfigType]['sorting']['headerFields'])) {
+            if (is_array($arrDataContainer[$strDcConfigType]['sorting']['headerFields'] ?? null) && !empty($arrDataContainer[$strDcConfigType]['sorting']['headerFields'])) {
 
                 $arrReturn['headerFields'] = $arrDataContainer[$strDcConfigType]['sorting']['headerFields'];
             }
@@ -380,7 +380,7 @@ protected function convertDcLabelToCatalog($arrReturn, $arrDataContainer, $strDc
             if (isset($arrDataContainer[$strDcConfigType]['label']['format'])) {
                 $arrReturn['format'] = $arrDataContainer[$strDcConfigType]['label']['format'];
             }
-            if ($arrDataContainer[$strDcConfigType]['label']['showColumns']) {
+            if (isset($arrDataContainer[$strDcConfigType]['label']['showColumns'])) {
                 $arrReturn['showColumns'] = '1';
             }
             if (isset($arrDataContainer[$strDcConfigType]['label']['fields']) && is_array($arrDataContainer[$strDcConfigType]['label']['fields']) && !empty($arrDataContainer[$strDcConfigType]['label']['fields'])) {
@@ -642,4 +642,4 @@ protected function convertCatalogToDcOperations($arrReturn, $arrCatalog, $strDcC
 
         return $arrReturn;
     }
-}
\ No newline at end of file
+}
diff --git a/library/alnv/CatalogView.php b/library/alnv/CatalogView.php
index 15070bc4..107d8872 100644
--- a/library/alnv/CatalogView.php
+++ b/library/alnv/CatalogView.php
@@ -1463,7 +1463,7 @@ protected function generateOperations( $strID, $strAlias = '', $arrCatalog = []
                     'href' => $this->generateUrl( $this->arrFrontendEditingPage, $strAlias ) . $strActFragment,
                     'title' => $GLOBALS['TL_LANG']['tl_module']['reference']['catalogItemOperations'][ $strOperation ],
                     'image' => \Image::getHtml( Toolkit::getIcon( $strOperation ), $GLOBALS['TL_LANG']['tl_module']['reference']['catalogItemOperations'][ $strOperation ] ),
-                    'attributes' => $strOperation === 'delete' ? 'onclick="if(!confirm(\'' . sprintf( $GLOBALS['TL_LANG']['MSC']['deleteConfirm'], $strID ) . '\'))return false;"' : '',
+                    'attributes' => $strOperation === 'delete' ? 'onclick="if(!confirm(\'' . sprintf( $GLOBALS['TL_LANG']['MSC']['deleteConfirm'] ?? '%s', $strID ) . '\'))return false;"' : '',
                 ];
             }
         }
@@ -1591,4 +1591,4 @@ public function getCatalogFields() {
 
         return $this->arrCatalogFields;
     }
-}
\ No newline at end of file
+}
diff --git a/library/alnv/Toolkit.php b/library/alnv/Toolkit.php
index 1125a802..61a74387 100644
--- a/library/alnv/Toolkit.php
+++ b/library/alnv/Toolkit.php
@@ -219,14 +219,13 @@ public static function customizeAbleFields()
 
     public static function parseCatalog($arrCatalog)
     {
-
-        $arrCatalog['cTables'] = self::parseStringToArray($arrCatalog['cTables']);
-        $arrCatalog['languages'] = self::parseStringToArray(($arrCatalog['languages'] ?? ''));
-        $arrCatalog['operations'] = self::parseStringToArray($arrCatalog['operations']);
-        $arrCatalog['panelLayout'] = self::parseStringToArray($arrCatalog['panelLayout']);
-        $arrCatalog['labelFields'] = self::parseStringToArray($arrCatalog['labelFields']);
-        $arrCatalog['headerFields'] = self::parseStringToArray($arrCatalog['headerFields']);
-        $arrCatalog['sortingFields'] = self::parseStringToArray($arrCatalog['sortingFields']);
+        $arrCatalog['cTables'] = self::parseStringToArray($arrCatalog['cTables'] ?? []);
+        $arrCatalog['languages'] = self::parseStringToArray($arrCatalog['languages'] ?? '');
+        $arrCatalog['operations'] = self::parseStringToArray($arrCatalog['operations'] ?? []);
+        $arrCatalog['panelLayout'] = self::parseStringToArray($arrCatalog['panelLayout'] ?? []);
+        $arrCatalog['labelFields'] = self::parseStringToArray($arrCatalog['labelFields'] ?? []);
+        $arrCatalog['headerFields'] = self::parseStringToArray($arrCatalog['headerFields'] ?? []);
+        $arrCatalog['sortingFields'] = self::parseStringToArray($arrCatalog['sortingFields'] ?? []);
 
         return $arrCatalog;
     }
@@ -1033,4 +1032,4 @@ public static function generateDynValue($strSimpleTokens, $arrValues)
 
         return \StringUtil::parseSimpleTokens($strSimpleTokens, $arrValues);
     }
-}
\ No newline at end of file
+}