diff --git a/.rector.php b/.rector.php
index cfb35e6e6f5..b1981b2d304 100644
--- a/.rector.php
+++ b/.rector.php
@@ -52,6 +52,7 @@
             CodeQuality\Class_\CompleteDynamicPropertiesRector::class, # todo: TMP (!?!)
             CodeQuality\Class_\InlineConstructorDefaultToPropertyRector::class, # todo: TMP
             CodeQuality\ClassMethod\ExplicitReturnNullRector::class, # todo: TMP
+            CodeQuality\ClassMethod\LocallyCalledStaticMethodToNonStaticRector::class, # todo: TMP
             CodeQuality\Empty_\SimplifyEmptyCheckOnEmptyArrayRector::class, # todo: TMP
             CodeQuality\Equal\UseIdenticalOverEqualWithSameTypeRector::class, # todo: TMP
             CodeQuality\Expression\InlineIfToExplicitIfRector::class, # todo: TMP (!?!)
@@ -113,7 +114,6 @@
             Php80\Class_\ClassPropertyAssignToConstructorPromotionRector::class, # todo: wait for php80
             Php80\Class_\StringableForToStringRector::class, # todo: wait for php80
             Php80\ClassMethod\AddParamBasedOnParentClassMethodRector::class, # todo: TMP
-            Php81\Array_\FirstClassCallableRector::class, # todo: TMP
             Php81\FuncCall\NullToStrictStringFuncCallArgRector::class, # todo: check later
             Strict\Empty_\DisallowedEmptyRuleFixerRector::class, # todo: TMP
             TypeDeclaration\BooleanAnd\BinaryOpNullableToInstanceofRector::class, # todo: TMP
diff --git a/app/code/core/Mage/Adminhtml/Block/Cache/Grid.php b/app/code/core/Mage/Adminhtml/Block/Cache/Grid.php
index 72190ea9094..9e6ed06fe65 100644
--- a/app/code/core/Mage/Adminhtml/Block/Cache/Grid.php
+++ b/app/code/core/Mage/Adminhtml/Block/Cache/Grid.php
@@ -86,7 +86,7 @@ protected function _prepareColumns()
             'index'     => 'status',
             'type'      => 'options',
             'options'   => [0 => $this->__('Disabled'), 1 => $this->__('Enabled')],
-            'frame_callback' => [$this, 'decorateStatus'],
+            'frame_callback' => $this->decorateStatus(...),
         ]);
 
         return parent::_prepareColumns();
diff --git a/app/code/core/Mage/Adminhtml/Block/Sales/Order/Status/Grid.php b/app/code/core/Mage/Adminhtml/Block/Sales/Order/Status/Grid.php
index 1684bbe1039..5c4103f2a4d 100644
--- a/app/code/core/Mage/Adminhtml/Block/Sales/Order/Status/Grid.php
+++ b/app/code/core/Mage/Adminhtml/Block/Sales/Order/Status/Grid.php
@@ -62,7 +62,7 @@ protected function _prepareColumns()
             'type'  => 'text',
             'index' => 'state',
             'width'     => '250px',
-            'frame_callback' => [$this, 'decorateState'],
+            'frame_callback' => $this->decorateState(...),
         ]);
 
         $this->addColumn('unassign', [
@@ -70,7 +70,7 @@ protected function _prepareColumns()
             'index'     => 'unassign',
             'width'     => '100px',
             'type'      => 'text',
-            'frame_callback' => [$this, 'decorateAction'],
+            'frame_callback' => $this->decorateAction(...),
             'sortable'  => false,
             'filter'    => false,
         ]);
diff --git a/app/code/core/Mage/Adminhtml/Block/Sales/Order/View/Info.php b/app/code/core/Mage/Adminhtml/Block/Sales/Order/View/Info.php
index 89c25d0d327..274a14cd38b 100644
--- a/app/code/core/Mage/Adminhtml/Block/Sales/Order/View/Info.php
+++ b/app/code/core/Mage/Adminhtml/Block/Sales/Order/View/Info.php
@@ -47,7 +47,7 @@ public function getOrderStoreName()
                 $store->getGroup()->getName(),
                 $store->getName(),
             ];
-            return implode('<br/>', array_map([$this, 'escapeHtml'], $name));
+            return implode('<br/>', array_map($this->escapeHtml(...), $name));
         }
 
         return null;
diff --git a/app/code/core/Mage/Adminhtml/Helper/Data.php b/app/code/core/Mage/Adminhtml/Helper/Data.php
index b9a1b44b5fb..ab26b3409ed 100644
--- a/app/code/core/Mage/Adminhtml/Helper/Data.php
+++ b/app/code/core/Mage/Adminhtml/Helper/Data.php
@@ -122,7 +122,7 @@ public function prepareFilterString($filterString)
         $data = [];
         $filterString = base64_decode($filterString);
         parse_str($filterString, $data);
-        array_walk_recursive($data, [$this, 'decodeFilter']);
+        array_walk_recursive($data, $this->decodeFilter(...));
         return $data;
     }
 
diff --git a/app/code/core/Mage/Adminhtml/Model/System/Config/Source/Allregion.php b/app/code/core/Mage/Adminhtml/Model/System/Config/Source/Allregion.php
index 763f48438e1..8f3e0e1f708 100644
--- a/app/code/core/Mage/Adminhtml/Model/System/Config/Source/Allregion.php
+++ b/app/code/core/Mage/Adminhtml/Model/System/Config/Source/Allregion.php
@@ -32,7 +32,7 @@ public function toOptionArray($isMultiselect = false)
                 $countryRegions[$region->getCountryId()][$region->getId()] = $region->getDefaultName();
             }
 
-            uksort($countryRegions, [$this, 'sortRegionCountries']);
+            uksort($countryRegions, $this->sortRegionCountries(...));
 
             $this->_options = [];
             foreach ($countryRegions as $countryId => $regions) {
diff --git a/app/code/core/Mage/Api/Model/Server/Handler/Abstract.php b/app/code/core/Mage/Api/Model/Server/Handler/Abstract.php
index 5c8246e1bce..a29a5aebdc7 100644
--- a/app/code/core/Mage/Api/Model/Server/Handler/Abstract.php
+++ b/app/code/core/Mage/Api/Model/Server/Handler/Abstract.php
@@ -18,7 +18,7 @@ abstract class Mage_Api_Model_Server_Handler_Abstract
 
     public function __construct()
     {
-        set_error_handler([$this, 'handlePhpError'], E_ALL);
+        set_error_handler($this->handlePhpError(...), E_ALL);
         Mage::app()->loadAreaPart(Mage_Core_Model_App_Area::AREA_ADMINHTML, Mage_Core_Model_App_Area::PART_EVENTS);
     }
 
diff --git a/app/code/core/Mage/Api2/Block/Adminhtml/Roles/Grid.php b/app/code/core/Mage/Api2/Block/Adminhtml/Roles/Grid.php
index eb133e2ee95..3699019389f 100644
--- a/app/code/core/Mage/Api2/Block/Adminhtml/Roles/Grid.php
+++ b/app/code/core/Mage/Api2/Block/Adminhtml/Roles/Grid.php
@@ -59,7 +59,7 @@ protected function _prepareColumns()
         $this->addColumn('tole_user_type', [
             'header'         => Mage::helper('oauth')->__('User Type'),
             'sortable'       => false,
-            'frame_callback' => [$this, 'decorateUserType'],
+            'frame_callback' => $this->decorateUserType(...),
         ]);
 
         $this->addColumn('created_at', [
diff --git a/app/code/core/Mage/Bundle/Model/Product/Type.php b/app/code/core/Mage/Bundle/Model/Product/Type.php
index 7fcc6ca2bf3..4bf843f6e22 100644
--- a/app/code/core/Mage/Bundle/Model/Product/Type.php
+++ b/app/code/core/Mage/Bundle/Model/Product/Type.php
@@ -632,7 +632,7 @@ protected function _prepareProduct(Varien_Object $buyRequest, $product, $process
             $selectionIds = [];
 
             // Shuffle selection array by option position
-            usort($selections, [$this, 'shakeSelections']);
+            usort($selections, $this->shakeSelections(...));
 
             foreach ($selections as $selection) {
                 if ($selection->getSelectionCanChangeQty() && isset($qtys[$selection->getOptionId()])) {
diff --git a/app/code/core/Mage/CatalogRule/Model/Rule.php b/app/code/core/Mage/CatalogRule/Model/Rule.php
index 3c0ea5a4cb2..0b3929391a5 100644
--- a/app/code/core/Mage/CatalogRule/Model/Rule.php
+++ b/app/code/core/Mage/CatalogRule/Model/Rule.php
@@ -220,7 +220,7 @@ public function getMatchingProductIds()
 
                 Mage::getSingleton('core/resource_iterator')->walk(
                     $productCollection->getSelect(),
-                    [[$this, 'callbackValidateProduct']],
+                    [$this->callbackValidateProduct(...)],
                     [
                         'attributes' => $this->getCollectedAttributes(),
                         'product'    => Mage::getModel('catalog/product'),
diff --git a/app/code/core/Mage/CatalogSearch/Helper/Data.php b/app/code/core/Mage/CatalogSearch/Helper/Data.php
index 8f67678e627..14c62100544 100644
--- a/app/code/core/Mage/CatalogSearch/Helper/Data.php
+++ b/app/code/core/Mage/CatalogSearch/Helper/Data.php
@@ -291,7 +291,7 @@ public function checkNotes($store = null)
             $wordsFull = $stringHelper->splitWords($this->getQueryText(), true);
             $wordsLike = $stringHelper->splitWords($this->getQueryText(), true, $this->getMaxQueryWords());
             if (count($wordsFull) > count($wordsLike)) {
-                $wordsCut = array_map([$this, 'escapeHtml'], array_diff($wordsFull, $wordsLike));
+                $wordsCut = array_map($this->escapeHtml(...), array_diff($wordsFull, $wordsLike));
                 $this->addNoteMessage(
                     $this->__('Maximum words count is %1$s. In your search query was cut next part: %2$s.', $this->getMaxQueryWords(), implode(' ', $wordsCut)),
                 );
diff --git a/app/code/core/Mage/Core/Model/Abstract.php b/app/code/core/Mage/Core/Model/Abstract.php
index 5850534ad70..493234ead3d 100644
--- a/app/code/core/Mage/Core/Model/Abstract.php
+++ b/app/code/core/Mage/Core/Model/Abstract.php
@@ -381,7 +381,7 @@ public function save()
                 $this->_afterSave();
             }
 
-            $this->_getResource()->addCommitCallback([$this, 'afterCommitCallback'])
+            $this->_getResource()->addCommitCallback($this->afterCommitCallback(...))
                 ->commit();
             $this->_hasDataChanges = false;
         } catch (Throwable $throwable) {
diff --git a/app/code/core/Mage/Core/Model/Cache.php b/app/code/core/Mage/Core/Model/Cache.php
index 3f0a655bdfc..4f5cd8e7fb9 100644
--- a/app/code/core/Mage/Core/Model/Cache.php
+++ b/app/code/core/Mage/Core/Model/Cache.php
@@ -241,7 +241,7 @@ protected function getDbAdapterOptions(array $options = [])
             $this->_dbConnection = $options['connection'];
         }
 
-        $options['adapter_callback'] = [$this, 'getDbAdapter'];
+        $options['adapter_callback'] = $this->getDbAdapter(...);
         $options['data_table'] = Mage::getSingleton('core/resource')->getTableName('core/cache');
         $options['tags_table'] = Mage::getSingleton('core/resource')->getTableName('core/cache_tag');
         return $options;
diff --git a/app/code/core/Mage/Core/Model/Design/Package.php b/app/code/core/Mage/Core/Model/Design/Package.php
index 1547b25f36a..7d24d31dc95 100644
--- a/app/code/core/Mage/Core/Model/Design/Package.php
+++ b/app/code/core/Mage/Core/Model/Design/Package.php
@@ -754,7 +754,7 @@ public function getMergedCssUrl($files)
             $files,
             $targetDir . DS . $targetFilename,
             false,
-            [$this, 'beforeMergeCss'],
+            $this->beforeMergeCss(...),
             'css',
         );
         if ($mergeFilesResult) {
diff --git a/app/code/core/Mage/Core/Model/Email/Template.php b/app/code/core/Mage/Core/Model/Email/Template.php
index a863adcd68c..45a521a83de 100644
--- a/app/code/core/Mage/Core/Model/Email/Template.php
+++ b/app/code/core/Mage/Core/Model/Email/Template.php
@@ -310,8 +310,8 @@ public function getProcessedTemplate(array $variables = [])
         $variables = $this->_addEmailVariables($variables, $processor->getStoreId());
 
         $processor
-            ->setTemplateProcessor([$this, 'getTemplateByConfigPath'])
-            ->setIncludeProcessor([$this, 'getInclude'])
+            ->setTemplateProcessor($this->getTemplateByConfigPath(...))
+            ->setIncludeProcessor($this->getInclude(...))
             ->setVariables($variables);
 
         try {
diff --git a/app/code/core/Mage/Core/Model/Email/Template/Filter.php b/app/code/core/Mage/Core/Model/Email/Template/Filter.php
index faeefdc44e0..7b3f0751cfc 100644
--- a/app/code/core/Mage/Core/Model/Email/Template/Filter.php
+++ b/app/code/core/Mage/Core/Model/Email/Template/Filter.php
@@ -61,7 +61,7 @@ class Mage_Core_Model_Email_Template_Filter extends Varien_Filter_Template
      */
     public function __construct()
     {
-        $this->_modifiers['escape'] = [$this, 'modifierEscape'];
+        $this->_modifiers['escape'] = $this->modifierEscape(...);
         $this->_permissionVariable = Mage::getModel('admin/variable');
         $this->_permissionBlock = Mage::getModel('admin/block');
     }
diff --git a/app/code/core/Mage/Core/Model/Resource/Session.php b/app/code/core/Mage/Core/Model/Resource/Session.php
index a4f7ac46cbf..3a6c8742b39 100644
--- a/app/code/core/Mage/Core/Model/Resource/Session.php
+++ b/app/code/core/Mage/Core/Model/Resource/Session.php
@@ -127,12 +127,12 @@ public function setSaveHandler()
     {
         if ($this->hasConnection()) {
             session_set_save_handler(
-                [$this, 'open'],
-                [$this, 'close'],
-                [$this, 'read'],
-                [$this, 'write'],
-                [$this, 'destroy'],
-                [$this, 'gc'],
+                $this->open(...),
+                $this->close(...),
+                $this->read(...),
+                $this->write(...),
+                $this->destroy(...),
+                $this->gc(...),
             );
         } else {
             session_save_path(Mage::getBaseDir('session'));
diff --git a/app/code/core/Mage/Core/Model/Url.php b/app/code/core/Mage/Core/Model/Url.php
index 2cdf8694f61..c00f729b2b4 100644
--- a/app/code/core/Mage/Core/Model/Url.php
+++ b/app/code/core/Mage/Core/Model/Url.php
@@ -1180,7 +1180,7 @@ public function sessionUrlVar($html)
         } else {
             return preg_replace_callback(
                 '#(\?|&amp;|&)___SID=([SU])(&amp;|&)?#',
-                [$this, 'sessionVarCallback'],
+                $this->sessionVarCallback(...),
                 $html,
             );
         }
diff --git a/app/code/core/Mage/Dataflow/Model/Convert/Iterator.php b/app/code/core/Mage/Dataflow/Model/Convert/Iterator.php
index 5392ab8d66a..bc265c9235a 100644
--- a/app/code/core/Mage/Dataflow/Model/Convert/Iterator.php
+++ b/app/code/core/Mage/Dataflow/Model/Convert/Iterator.php
@@ -27,7 +27,7 @@ public function walk()
             $callbacks[] = $adapterCb;
         }
 
-        $callbacks[] = [$this, 'updateProgress'];
+        $callbacks[] = $this->updateProgress(...);
 
         echo $this->_getProgressBarHtml($sessionId, $total['cnt']);
 
diff --git a/app/code/core/Mage/Eav/Model/Entity/Abstract.php b/app/code/core/Mage/Eav/Model/Entity/Abstract.php
index 87bd00d76c2..ac652c03d98 100644
--- a/app/code/core/Mage/Eav/Model/Entity/Abstract.php
+++ b/app/code/core/Mage/Eav/Model/Entity/Abstract.php
@@ -539,7 +539,7 @@ public function getSortedAttributes($setId = null)
         }
 
         $this->_sortingSetId = $setId;
-        uasort($attributes, [$this, 'attributesCompare']);
+        uasort($attributes, $this->attributesCompare(...));
         return $attributes;
     }
 
diff --git a/app/code/core/Mage/ImportExport/Block/Adminhtml/Export/Filter.php b/app/code/core/Mage/ImportExport/Block/Adminhtml/Export/Filter.php
index 30008e3f200..96cebc9c8ff 100644
--- a/app/code/core/Mage/ImportExport/Block/Adminhtml/Export/Filter.php
+++ b/app/code/core/Mage/ImportExport/Block/Adminhtml/Export/Filter.php
@@ -347,7 +347,7 @@ protected function _prepareColumns()
             'header'         => Mage::helper('importexport')->__('Filter'),
             'sortable'       => false,
             'filter'         => false,
-            'frame_callback' => [$this, 'decorateFilter'],
+            'frame_callback' => $this->decorateFilter(...),
         ]);
 
         if ($this->hasOperation()) {
diff --git a/app/code/core/Mage/Index/Block/Adminhtml/Process/Grid.php b/app/code/core/Mage/Index/Block/Adminhtml/Process/Grid.php
index 94b94c87f44..9965a1bfed1 100644
--- a/app/code/core/Mage/Index/Block/Adminhtml/Process/Grid.php
+++ b/app/code/core/Mage/Index/Block/Adminhtml/Process/Grid.php
@@ -120,7 +120,7 @@ protected function _prepareColumns()
             'index'     => 'status',
             'type'      => 'options',
             'options'   => $this->_processModel->getStatusesOptions(),
-            'frame_callback' => [$this, 'decorateStatus'],
+            'frame_callback' => $this->decorateStatus(...),
         ]);
 
         $this->addColumn('update_required', [
@@ -131,7 +131,7 @@ protected function _prepareColumns()
             'index'     => 'update_required',
             'type'      => 'options',
             'options'   => $this->_processModel->getUpdateRequiredOptions(),
-            'frame_callback' => [$this, 'decorateUpdateRequired'],
+            'frame_callback' => $this->decorateUpdateRequired(...),
         ]);
 
         $this->addColumn('ended_at', [
@@ -139,7 +139,7 @@ protected function _prepareColumns()
             'type'      => 'datetime',
             'align'     => 'left',
             'index'     => 'ended_at',
-            'frame_callback' => [$this, 'decorateDate'],
+            'frame_callback' => $this->decorateDate(...),
         ]);
 
         $this->addColumn(
diff --git a/app/code/core/Mage/Newsletter/Model/Template.php b/app/code/core/Mage/Newsletter/Model/Template.php
index 43f74f97f5b..6ab89dbd8b0 100644
--- a/app/code/core/Mage/Newsletter/Model/Template.php
+++ b/app/code/core/Mage/Newsletter/Model/Template.php
@@ -197,8 +197,8 @@ public function getProcessedTemplate(array $variables = [], $usePreprocess = fal
         $variables = $this->_addEmailVariables($variables, $processor->getStoreId());
 
         $processor
-            ->setTemplateProcessor([$this, 'getTemplateByConfigPath'])
-            ->setIncludeProcessor([$this, 'getInclude'])
+            ->setTemplateProcessor($this->getTemplateByConfigPath(...))
+            ->setIncludeProcessor($this->getInclude(...))
             ->setVariables($variables);
 
         // Filter the template text so that all HTML content will be present
diff --git a/app/code/core/Mage/Oauth/Block/Adminhtml/Oauth/AuthorizedTokens/Grid.php b/app/code/core/Mage/Oauth/Block/Adminhtml/Oauth/AuthorizedTokens/Grid.php
index 43e2d598f8c..5d6d1523ba1 100644
--- a/app/code/core/Mage/Oauth/Block/Adminhtml/Oauth/AuthorizedTokens/Grid.php
+++ b/app/code/core/Mage/Oauth/Block/Adminhtml/Oauth/AuthorizedTokens/Grid.php
@@ -66,13 +66,13 @@ protected function _prepareColumns()
             'header'    => $this->__('User Type'),
             //'index'     => array('customer_id', 'admin_id'),
             'options'   => [0 => $this->__('Admin'), 1 => $this->__('Customer')],
-            'frame_callback' => [$this, 'decorateUserType'],
+            'frame_callback' => $this->decorateUserType(...),
         ]);
 
         $this->addColumn('user_id', [
             'header'    => $this->__('User ID'),
             //'index'     => array('customer_id', 'admin_id'),
-            'frame_callback' => [$this, 'decorateUserId'],
+            'frame_callback' => $this->decorateUserId(...),
         ]);
 
         /** @var Mage_Adminhtml_Model_System_Config_Source_Yesno $sourceYesNo */
diff --git a/app/code/core/Mage/Paypal/Block/Adminhtml/System/Config/Fieldset/Deprecated.php b/app/code/core/Mage/Paypal/Block/Adminhtml/System/Config/Fieldset/Deprecated.php
index a9154f08aff..c5bb93ede42 100644
--- a/app/code/core/Mage/Paypal/Block/Adminhtml/System/Config/Fieldset/Deprecated.php
+++ b/app/code/core/Mage/Paypal/Block/Adminhtml/System/Config/Fieldset/Deprecated.php
@@ -106,7 +106,7 @@ public function isPaymentEnabledAnyScope($activityPath)
      */
     public function render(Varien_Data_Form_Element_Abstract $element)
     {
-        $isPaymentEnabled = $this->_isPaymentEnabled($element, [$this, 'isPaymentEnabledAnyScope']);
+        $isPaymentEnabled = $this->_isPaymentEnabled($element, $this->isPaymentEnabledAnyScope(...));
         if ($this->_wasActive($element) && $isPaymentEnabled) {
             return parent::render($element);
         }
diff --git a/app/code/core/Mage/Paypal/Model/Api/Abstract.php b/app/code/core/Mage/Paypal/Model/Api/Abstract.php
index 8c918dadf3d..20bf89cef66 100644
--- a/app/code/core/Mage/Paypal/Model/Api/Abstract.php
+++ b/app/code/core/Mage/Paypal/Model/Api/Abstract.php
@@ -243,7 +243,7 @@ public function getBusinessAccount()
      */
     public function &import($to, array $publicMap = [])
     {
-        return Varien_Object_Mapper::accumulateByMap([$this, 'getDataUsingMethod'], $to, $publicMap);
+        return Varien_Object_Mapper::accumulateByMap($this->getDataUsingMethod(...), $to, $publicMap);
     }
 
     /**
@@ -254,7 +254,7 @@ public function &import($to, array $publicMap = [])
      */
     public function export($from, array $publicMap = [])
     {
-        Varien_Object_Mapper::accumulateByMap($from, [$this, 'setDataUsingMethod'], $publicMap);
+        Varien_Object_Mapper::accumulateByMap($from, $this->setDataUsingMethod(...), $publicMap);
         return $this;
     }
 
@@ -325,7 +325,7 @@ protected function &_exportToRequest(array $privateRequestMap, array $request =
             }
         }
 
-        $result = Varien_Object_Mapper::accumulateByMap([$this, 'getDataUsingMethod'], $request, $map);
+        $result = Varien_Object_Mapper::accumulateByMap($this->getDataUsingMethod(...), $request, $map);
         foreach ($privateRequestMap as $key) {
             if (isset($this->_exportToRequestFilters[$key]) && isset($result[$key])) {
                 $callback   = $this->_exportToRequestFilters[$key];
@@ -355,7 +355,7 @@ protected function _importFromResponse(array $privateResponseMap, array $respons
             }
         }
 
-        Varien_Object_Mapper::accumulateByMap($response, [$this, 'setDataUsingMethod'], $map);
+        Varien_Object_Mapper::accumulateByMap($response, $this->setDataUsingMethod(...), $map);
     }
 
     /**
diff --git a/app/code/core/Mage/Paypal/Model/Express/Checkout.php b/app/code/core/Mage/Paypal/Model/Express/Checkout.php
index 34eac5a6ee4..f085f8beae4 100644
--- a/app/code/core/Mage/Paypal/Model/Express/Checkout.php
+++ b/app/code/core/Mage/Paypal/Model/Express/Checkout.php
@@ -869,7 +869,7 @@ protected function _prepareShippingOptions(
 
         // Magento will transfer only first 10 cheapest shipping options if there are more than 10 available.
         if (count($options) > 10) {
-            usort($options, [static::class,'cmpShippingOptions']);
+            usort($options, static::cmpShippingOptions(...));
             array_splice($options, 10);
             // User selected option will be always included in options list
             if (!is_null($userSelectedOption) && !in_array($userSelectedOption, $options)) {
diff --git a/app/code/core/Mage/Paypal/Model/Info.php b/app/code/core/Mage/Paypal/Model/Info.php
index ee175d19fe6..5657c15c603 100644
--- a/app/code/core/Mage/Paypal/Model/Info.php
+++ b/app/code/core/Mage/Paypal/Model/Info.php
@@ -221,7 +221,7 @@ public function importToPayment($from, Mage_Payment_Model_Info $payment)
             $from = [$from, 'getDataUsingMethod'];
         }
 
-        Varien_Object_Mapper::accumulateByMap($from, [$payment, 'setAdditionalInformation'], $fullMap);
+        Varien_Object_Mapper::accumulateByMap($from, $payment->setAdditionalInformation(...), $fullMap);
     }
 
     /**
@@ -234,7 +234,7 @@ public function &exportFromPayment(Mage_Payment_Model_Info $payment, $to, ?array
     {
         $fullMap = array_merge($this->_paymentMap, $this->_systemMap);
         Varien_Object_Mapper::accumulateByMap(
-            [$payment, 'getAdditionalInformation'],
+            $payment->getAdditionalInformation(...),
             $to,
             $map ? $map : array_flip($fullMap),
         );
diff --git a/app/code/core/Mage/Rss/Block/Catalog/New.php b/app/code/core/Mage/Rss/Block/Catalog/New.php
index db72334dfa0..e54e7c7469c 100644
--- a/app/code/core/Mage/Rss/Block/Catalog/New.php
+++ b/app/code/core/Mage/Rss/Block/Catalog/New.php
@@ -87,7 +87,7 @@ protected function _toHtml()
         */
         Mage::getSingleton('core/resource_iterator')->walk(
             $products->getSelect(),
-            [[$this, 'addNewItemXmlCallback']],
+            [$this->addNewItemXmlCallback(...)],
             ['rssObj' => $rssObj, 'product' => $product],
         );
 
diff --git a/app/code/core/Mage/Rss/Block/Catalog/NotifyStock.php b/app/code/core/Mage/Rss/Block/Catalog/NotifyStock.php
index d5c52aa03f3..484706d718a 100644
--- a/app/code/core/Mage/Rss/Block/Catalog/NotifyStock.php
+++ b/app/code/core/Mage/Rss/Block/Catalog/NotifyStock.php
@@ -78,7 +78,7 @@ protected function _toHtml()
         */
         Mage::getSingleton('core/resource_iterator')->walk(
             $collection->getSelect(),
-            [[$this, 'addNotifyItemXmlCallback']],
+            [$this->addNotifyItemXmlCallback(...)],
             ['rssObj' => $rssObj, 'product' => $product, 'globalQty' => $globalNotifyStockQty],
         );
 
diff --git a/app/code/core/Mage/Rss/Block/Catalog/Review.php b/app/code/core/Mage/Rss/Block/Catalog/Review.php
index be65810492d..5bb61afe5e0 100644
--- a/app/code/core/Mage/Rss/Block/Catalog/Review.php
+++ b/app/code/core/Mage/Rss/Block/Catalog/Review.php
@@ -65,7 +65,7 @@ protected function _toHtml()
 
         Mage::getSingleton('core/resource_iterator')->walk(
             $collection->getSelect(),
-            [[$this, 'addReviewItemXmlCallback']],
+            [$this->addReviewItemXmlCallback(...)],
             ['rssObj' => $rssObj, 'reviewModel' => $reviewModel],
         );
         return $rssObj->createRssXml();
diff --git a/app/code/core/Mage/Rss/Block/Catalog/Special.php b/app/code/core/Mage/Rss/Block/Catalog/Special.php
index d12d9958856..0d221ff76b9 100644
--- a/app/code/core/Mage/Rss/Block/Catalog/Special.php
+++ b/app/code/core/Mage/Rss/Block/Catalog/Special.php
@@ -90,7 +90,7 @@ protected function _toHtml()
         */
         Mage::getSingleton('core/resource_iterator')->walk(
             $specials->getSelect(),
-            [[$this, 'addSpecialXmlCallback']],
+            [$this->addSpecialXmlCallback(...)],
             ['rssObj' => $rssObj, 'results' => &$results],
         );
 
diff --git a/app/code/core/Mage/Rss/Block/Catalog/Tag.php b/app/code/core/Mage/Rss/Block/Catalog/Tag.php
index 5e622877483..cf4b012e121 100644
--- a/app/code/core/Mage/Rss/Block/Catalog/Tag.php
+++ b/app/code/core/Mage/Rss/Block/Catalog/Tag.php
@@ -61,7 +61,7 @@ protected function _toHtml()
         $resourceHelper = Mage::getResourceHelper('core');
         Mage::getSingleton('core/resource_iterator')->walk(
             $resourceHelper->getQueryUsingAnalyticFunction($collection->getSelect()),
-            [[$this, 'addTaggedItemXml']],
+            [$this->addTaggedItemXml(...)],
             ['rssObj' => $rssObj, 'product' => $product],
             $collection->getSelect()->getAdapter(),
         );
diff --git a/app/code/core/Mage/Rss/Block/Order/New.php b/app/code/core/Mage/Rss/Block/Order/New.php
index 1b6d5957acf..207f7a42599 100644
--- a/app/code/core/Mage/Rss/Block/Order/New.php
+++ b/app/code/core/Mage/Rss/Block/Order/New.php
@@ -69,7 +69,7 @@ protected function _toHtml()
         Mage::dispatchEvent('rss_order_new_collection_select', ['collection' => $collection]);
 
         Mage::getSingleton('core/resource_iterator')
-            ->walk($collection->getSelect(), [[$this, 'addNewOrderXmlCallback']], ['rssObj' => $rssObj, 'order' => $order , 'detailBlock' => $detailBlock]);
+            ->walk($collection->getSelect(), [$this->addNewOrderXmlCallback(...)], ['rssObj' => $rssObj, 'order' => $order , 'detailBlock' => $detailBlock]);
 
         return $rssObj->createRssXml();
     }
diff --git a/app/code/core/Mage/Sales/Model/Service/Quote.php b/app/code/core/Mage/Sales/Model/Service/Quote.php
index b9decf63a53..be28aa32960 100644
--- a/app/code/core/Mage/Sales/Model/Service/Quote.php
+++ b/app/code/core/Mage/Sales/Model/Service/Quote.php
@@ -163,8 +163,8 @@ public function submitOrder()
         $order->setQuote($quote);
 
         $transaction->addObject($order);
-        $transaction->addCommitCallback([$order, 'place']);
-        $transaction->addCommitCallback([$order, 'save']);
+        $transaction->addCommitCallback($order->place(...));
+        $transaction->addCommitCallback($order->save(...));
 
         Mage::unregister('current_order');
         Mage::register('current_order', $order);
diff --git a/app/code/core/Mage/Uploader/Block/Abstract.php b/app/code/core/Mage/Uploader/Block/Abstract.php
index 795527ce82d..ce179a908a6 100644
--- a/app/code/core/Mage/Uploader/Block/Abstract.php
+++ b/app/code/core/Mage/Uploader/Block/Abstract.php
@@ -235,6 +235,6 @@ public function getElementId($suffix)
      */
     protected function _prepareElementsIds($targets)
     {
-        return array_map([$this, 'getElementId'], array_unique(array_values($targets)));
+        return array_map($this->getElementId(...), array_unique(array_values($targets)));
     }
 }
diff --git a/app/code/core/Mage/Uploader/Helper/File.php b/app/code/core/Mage/Uploader/Helper/File.php
index 74ad13edada..3f412be14b4 100644
--- a/app/code/core/Mage/Uploader/Helper/File.php
+++ b/app/code/core/Mage/Uploader/Helper/File.php
@@ -670,7 +670,7 @@ public function getMimeTypeFromExtensionList($extensionsList)
             $extensionsList = array_map(trim(...), explode(',', $extensionsList));
         }
 
-        return array_map([$this, 'getMimeTypeByExtension'], $extensionsList);
+        return array_map($this->getMimeTypeByExtension(...), $extensionsList);
     }
 
     /**
diff --git a/lib/Varien/Data/Collection/Filesystem.php b/lib/Varien/Data/Collection/Filesystem.php
index cb71d331c7b..76d0f8e82bc 100644
--- a/lib/Varien/Data/Collection/Filesystem.php
+++ b/lib/Varien/Data/Collection/Filesystem.php
@@ -470,78 +470,78 @@ public function addFieldToFilter($field, $cond, $type = 'and')
 
         // simply check whether equals
         if (!is_array($cond)) {
-            return $this->addCallbackFilter($field, $cond, $type, [$this, 'filterCallbackEq']);
+            return $this->addCallbackFilter($field, $cond, $type, $this->filterCallbackEq(...));
         }
 
         // versatile filters
         if (isset($cond['from']) || isset($cond['to'])) {
             $this->_addFilterBracket('(', 'and' === $type);
             if (isset($cond['from'])) {
-                $this->addCallbackFilter($field, $cond['from'], 'and', [$this, 'filterCallbackIsLessThan'], $inverted);
+                $this->addCallbackFilter($field, $cond['from'], 'and', $this->filterCallbackIsLessThan(...), $inverted);
             }
 
             if (isset($cond['to'])) {
-                $this->addCallbackFilter($field, $cond['to'], 'and', [$this, 'filterCallbackIsMoreThan'], $inverted);
+                $this->addCallbackFilter($field, $cond['to'], 'and', $this->filterCallbackIsMoreThan(...), $inverted);
             }
 
             return $this->_addFilterBracket(')');
         }
 
         if (isset($cond['eq'])) {
-            return $this->addCallbackFilter($field, $cond['eq'], $type, [$this, 'filterCallbackEq']);
+            return $this->addCallbackFilter($field, $cond['eq'], $type, $this->filterCallbackEq(...));
         }
 
         if (isset($cond['neq'])) {
-            return $this->addCallbackFilter($field, $cond['neq'], $type, [$this, 'filterCallbackEq'], $inverted);
+            return $this->addCallbackFilter($field, $cond['neq'], $type, $this->filterCallbackEq(...), $inverted);
         }
 
         if (isset($cond['like'])) {
-            return $this->addCallbackFilter($field, $cond['like'], $type, [$this, 'filterCallbackLike']);
+            return $this->addCallbackFilter($field, $cond['like'], $type, $this->filterCallbackLike(...));
         }
 
         if (isset($cond['nlike'])) {
-            return $this->addCallbackFilter($field, $cond['nlike'], $type, [$this, 'filterCallbackLike'], $inverted);
+            return $this->addCallbackFilter($field, $cond['nlike'], $type, $this->filterCallbackLike(...), $inverted);
         }
 
         if (isset($cond['in'])) {
-            return $this->addCallbackFilter($field, $cond['in'], $type, [$this, 'filterCallbackInArray']);
+            return $this->addCallbackFilter($field, $cond['in'], $type, $this->filterCallbackInArray(...));
         }
 
         if (isset($cond['nin'])) {
-            return $this->addCallbackFilter($field, $cond['nin'], $type, [$this, 'filterCallbackInArray'], $inverted);
+            return $this->addCallbackFilter($field, $cond['nin'], $type, $this->filterCallbackInArray(...), $inverted);
         }
 
         if (isset($cond['notnull'])) {
-            return $this->addCallbackFilter($field, $cond['notnull'], $type, [$this, 'filterCallbackIsNull'], $inverted);
+            return $this->addCallbackFilter($field, $cond['notnull'], $type, $this->filterCallbackIsNull(...), $inverted);
         }
 
         if (isset($cond['null'])) {
-            return $this->addCallbackFilter($field, $cond['null'], $type, [$this, 'filterCallbackIsNull']);
+            return $this->addCallbackFilter($field, $cond['null'], $type, $this->filterCallbackIsNull(...));
         }
 
         if (isset($cond['moreq'])) {
-            return $this->addCallbackFilter($field, $cond['moreq'], $type, [$this, 'filterCallbackIsLessThan'], $inverted);
+            return $this->addCallbackFilter($field, $cond['moreq'], $type, $this->filterCallbackIsLessThan(...), $inverted);
         }
 
         if (isset($cond['gt'])) {
-            return $this->addCallbackFilter($field, $cond['gt'], $type, [$this, 'filterCallbackIsMoreThan']);
+            return $this->addCallbackFilter($field, $cond['gt'], $type, $this->filterCallbackIsMoreThan(...));
         }
 
         if (isset($cond['lt'])) {
-            return $this->addCallbackFilter($field, $cond['lt'], $type, [$this, 'filterCallbackIsLessThan']);
+            return $this->addCallbackFilter($field, $cond['lt'], $type, $this->filterCallbackIsLessThan(...));
         }
 
         if (isset($cond['gteq'])) {
-            return $this->addCallbackFilter($field, $cond['gteq'], $type, [$this, 'filterCallbackIsLessThan'], $inverted);
+            return $this->addCallbackFilter($field, $cond['gteq'], $type, $this->filterCallbackIsLessThan(...), $inverted);
         }
 
         if (isset($cond['lteq'])) {
-            return $this->addCallbackFilter($field, $cond['lteq'], $type, [$this, 'filterCallbackIsMoreThan'], $inverted);
+            return $this->addCallbackFilter($field, $cond['lteq'], $type, $this->filterCallbackIsMoreThan(...), $inverted);
         }
 
         if (isset($cond['finset'])) {
             $filterValue = ($cond['finset'] ? explode(',', $cond['finset']) : []);
-            return $this->addCallbackFilter($field, $filterValue, $type, [$this, 'filterCallbackInArray']);
+            return $this->addCallbackFilter($field, $filterValue, $type, $this->filterCallbackInArray(...));
         }
 
         // add OR recursively
diff --git a/lib/Varien/Db/Adapter/Pdo/Mysql.php b/lib/Varien/Db/Adapter/Pdo/Mysql.php
index d7847ad8c50..642ae0d875b 100644
--- a/lib/Varien/Db/Adapter/Pdo/Mysql.php
+++ b/lib/Varien/Db/Adapter/Pdo/Mysql.php
@@ -1767,10 +1767,7 @@ public function describeTable($tableName, $schemaName = null)
         $ddl = $this->loadDdlCache($cacheKey, self::DDL_DESCRIBE);
         if ($ddl === false) {
             $ddl = array_map(
-                [
-                    $this,
-                    'decorateTableInfo',
-                ],
+                $this->decorateTableInfo(...),
                 parent::describeTable($tableName, $schemaName),
             );
             /**
@@ -2369,7 +2366,7 @@ protected function _getColumnsDefinition(Varien_Db_Ddl_Table $table)
         // PRIMARY KEY
         if (!empty($primary)) {
             asort($primary, SORT_NUMERIC);
-            $primary      = array_map([$this, 'quoteIdentifier'], array_keys($primary));
+            $primary      = array_map($this->quoteIdentifier(...), array_keys($primary));
             $definition[] = sprintf('  PRIMARY KEY (%s)', implode(', ', $primary));
         }
 
@@ -3645,7 +3642,7 @@ public function insertFromSelect(Varien_Db_Select $select, $table, array $fields
 
         $query = sprintf('%s INTO %s', $query, $this->quoteIdentifier($table));
         if ($fields) {
-            $columns = array_map([$this, 'quoteIdentifier'], $fields);
+            $columns = array_map($this->quoteIdentifier(...), $fields);
             $query = sprintf('%s (%s)', $query, implode(', ', $columns));
         }
 
@@ -3971,7 +3968,7 @@ protected function _prepareInsertData($row, &$bind)
     protected function _getInsertSqlQuery($tableName, array $columns, array $values)
     {
         $tableName = $this->quoteIdentifier($tableName, true);
-        $columns   = array_map([$this, 'quoteIdentifier'], $columns);
+        $columns   = array_map($this->quoteIdentifier(...), $columns);
         $columns   = implode(',', $columns);
 
         $values    = implode(', ', $values);