diff --git a/Classes/Backend/FlexformHelper.php b/Classes/Backend/FlexformHelper.php
index f0c1a5f..bf6d48e 100644
--- a/Classes/Backend/FlexformHelper.php
+++ b/Classes/Backend/FlexformHelper.php
@@ -11,7 +11,6 @@
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Extbase\Configuration\ConfigurationManager;
 use TYPO3\CMS\Extbase\Configuration\ConfigurationManagerInterface;
-use TYPO3\CMS\Extbase\Object\ObjectManager;
 
 /**
  * Helper functions for Flexform
diff --git a/Classes/Backend/TceForms.php b/Classes/Backend/TceForms.php
deleted file mode 100644
index be1579d..0000000
--- a/Classes/Backend/TceForms.php
+++ /dev/null
@@ -1,95 +0,0 @@
-<?php
-namespace Fab\RssDisplay\Backend;
-
-/*
- * This file is part of the Fab/RssDisplay project under GPLv2 or later.
- *
- * For the full copyright and license information, please read the
- * LICENSE.md file that was distributed with this source code.
- */
-
-use TYPO3\CMS\Core\Utility\GeneralUtility;
-use TYPO3\CMS\Extbase\Configuration\BackendConfigurationManager;
-use TYPO3\CMS\Extbase\Object\ObjectManager;
-use TYPO3\CMS\Backend\Form\Element\AbstractFormElement;
-
-/**
- * Backend integration with TCEForms
- *
- * @deprecated No longer used, will be removed
- */
-class TceForms extends AbstractFormElement
-{
-
-    /**
-     * Render a template menu.
-     *
-     * @param array $row
-     * @return string
-     * @throws \InvalidArgumentException
-     */
-    public function renderTemplateMenu($row)
-    {
-        $configurationManager = GeneralUtility::makeInstance(BackendConfigurationManager::class);
-
-        $setup = $configurationManager->getTypoScriptSetup();
-        $configuration = $this->getPluginConfiguration($setup, 'rssdisplay');
-
-        $output = '';
-        if (is_array($configuration['settings']['templates'])) {
-
-            $selectedItem = '';
-            if (!empty($row['pi_flexform'])) {
-                $values = $row['pi_flexform'];
-                if (!empty($values['data']['sDEF']['lDEF']['settings.template'])) {
-                    $selectedItem = $values['data']['sDEF']['lDEF']['settings.template']['vDEF'];
-                }
-            }
-
-            $options = array();
-            foreach ($configuration['settings']['templates'] as $template) {
-                $options[] = sprintf('<option value="%s" %s>%s</option>',
-                    $template['path'],
-                    $selectedItem == $template['path'] ? 'selected="selected"' : '',
-                    $template['label']
-                );
-            }
-
-            $output = sprintf('<select name="data[tt_content][%s][pi_flexform][data][sDEF][lDEF][settings.template][vDEF]">%s</select>',
-                $row['uid'],
-                implode("\n", $options)
-            );
-        }
-        return $output;
-    }
-
-    /**
-     * Render a template.
-     *
-     * @return array
-     */
-    public function render() {
-        $result = $this->initializeResultArray();
-        $result["html"] = $this->renderTemplateMenu($this->data["databaseRow"]);
-        return $result;
-    }
-
-    /**
-     * Returns the TypoScript configuration found an extension name
-     *
-     * @param array $setup
-     * @param string $extensionName
-     * @return array
-     * @throws \InvalidArgumentException
-     */
-    protected function getPluginConfiguration(array $setup, $extensionName)
-    {
-        $pluginConfiguration = array();
-        if (is_array($setup['plugin.']['tx_' . strtolower($extensionName) . '.'])) {
-            /** @var \TYPO3\CMS\Core\TypoScript\TypoScriptService $typoScriptService */
-            $typoScriptService = GeneralUtility::makeInstance('TYPO3\CMS\Core\TypoScript\TypoScriptService');
-            $pluginConfiguration = $typoScriptService->convertTypoScriptArrayToPlainArray($setup['plugin.']['tx_' . strtolower($extensionName) . '.']);
-        }
-        return $pluginConfiguration;
-    }
-}
diff --git a/Classes/Backend/Wizard.php b/Classes/Backend/Wizard.php
deleted file mode 100644
index 24ef98e..0000000
--- a/Classes/Backend/Wizard.php
+++ /dev/null
@@ -1,59 +0,0 @@
-<?php
-namespace Fab\RssDisplay\Backend;
-
-/*
- * This file is part of the Fab/RssDisplay project under GPLv2 or later.
- *
- * For the full copyright and license information, please read the
- * LICENSE.md file that was distributed with this source code.
- */
-
-use TYPO3\CMS\Backend\Wizard\NewContentElementWizardHookInterface;
-
-
-/**
- * Class that adds the wizard icon.
- */
-class Wizard implements NewContentElementWizardHookInterface
-{
-
-    /**
-     * Processing the wizard items array
-     *
-     * @param array $wizardItems The wizard items
-     */
-    public function manipulateWizardItems(&$wizardItems, &$parentObject)
-    {
-        # Find index of last plugin.
-        foreach (array_keys($wizardItems) as $index => $key) {
-            if(strpos($key, 'plugin') === 0) {
-                $found = true;
-            } elseif (isset($found)) {
-                array_splice($wizardItems, $index, 0, [
-                    'plugins_tx_rssdisplay_pi1' => [
-                        'iconIdentifier' => 'plugins_tx_rssdisplay_pi1_wizard', // <- see ext_tables.php
-                        'iconIdentifier' => 'ext-news-wizard-icon', // <- see ext_tables.php
-                        'title' => $this->getLanguageService()->sL('LLL:EXT:rss_display/Resources/Private/Language/locallang.xlf:wizard.title'),
-                        'description' => $this->getLanguageService()->sL('LLL:EXT:rss_display/Resources/Private/Language/locallang.xlf:wizard.description'),
-                        'saveAndClose' => false,
-                        'tt_content_defValues' => [
-                            'CType' => "list",
-                            'list_type' => "rssdisplay_pi1"
-                        ],
-                        'params' => '&defVals[tt_content][CType]=list&defVals[tt_content][list_type]=rssdisplay_pi1'
-                    ]
-                ]);
-                break;
-            };
-        }
-    }
-
-    /**
-     * @return \TYPO3\CMS\Core\Localization\LanguageService
-     */
-    protected function getLanguageService(): \TYPO3\CMS\Core\Localization\LanguageService
-    {
-        return $GLOBALS['LANG'];
-    }
-
-}
diff --git a/Classes/Controller/FeedController.php b/Classes/Controller/FeedController.php
index b6410b9..89f4dae 100755
--- a/Classes/Controller/FeedController.php
+++ b/Classes/Controller/FeedController.php
@@ -16,6 +16,7 @@
 use TYPO3\CMS\Core\Core\Environment;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Extbase\Mvc\Controller\ActionController;
+use Psr\Http\Message\ResponseInterface;
 
 /**
  * RSS display that will fetch the content of a RSS Feed and display it onto the Frontend.
@@ -31,7 +32,7 @@ class FeedController extends ActionController
      * Initialize object
      * @throws \RuntimeException
      */
-    public function initializeAction()
+    public function initializeAction(): void
     {
         if (empty($this->settings['template'])) {
             $this->settings['template'] = 'EXT:rss_display/Resources/Private/Templates/Feed/Show.html';
@@ -45,10 +46,9 @@ public function initializeAction()
     }
 
     /**
-     * @return string
      * @throws \Exception
      */
-    public function showAction()
+    public function showAction(): ResponseInterface
     {
 
         // @todo !! better add check if the Feed URL is alive. If not log it and send an email to the webmaster.
@@ -68,7 +68,7 @@ public function showAction()
             $this->view->assign('title', $feed->get_title());
             $this->view->assign('items', $feed->get_items(0, (int)$this->settings['numberOfItems']));
             $this->view->assign('settings', $this->settings);
-            $cObj = $this->configurationManager->getContentObject();
+            $cObj = $this->request->getAttribute('currentContentObject');
             $this->view->assign('data', $cObj->data);
             $result = $this->view->render();
 
@@ -79,7 +79,7 @@ public function showAction()
             }
         }
 
-        return $result;
+        return $this->htmlResponse($result);
     }
 
     /**
@@ -106,7 +106,7 @@ protected function canFetchResultFromCache()
         $result = FALSE;
         if ($this->getPluginType() === self::PLUGIN_TYPE_USER_INT
             && $this->getCacheInstance()->has($this->getCacheIdentifier())
-            && !GeneralUtility::_GET('no_cache')
+            && !($this->request->getQueryParams()['no_cache'] ?? null)
         ) {
             $result = TRUE;
         }
diff --git a/Configuration/FlexForm/feed.xml b/Configuration/FlexForm/feed.xml
index 2bc7d89..bf36c11 100644
--- a/Configuration/FlexForm/feed.xml
+++ b/Configuration/FlexForm/feed.xml
@@ -11,37 +11,30 @@
 				<type>array</type>
 				<el>
 					<settings.feedUrl>
-						<TCEforms>
-							<label>LLL:EXT:rss_display/Resources/Private/Language/locallang.xlf:tt_content.tx_rssdisplay_feedUrl</label>
-							<config>
-								<type>input</type>
-								<size>50</size>
-								<max>400</max>
-								<default>http://www.w3.org/blog/news/feed/atom</default>
-							</config>
-						</TCEforms>
+						<label>LLL:EXT:rss_display/Resources/Private/Language/locallang.xlf:tt_content.tx_rssdisplay_feedUrl</label>
+						<config>
+							<type>input</type>
+							<size>50</size>
+							<max>400</max>
+							<default>http://www.w3.org/blog/news/feed/atom</default>
+						</config>
 					</settings.feedUrl>
 					<settings.numberOfItems>
-						<TCEforms>
-							<label>LLL:EXT:rss_display/Resources/Private/Language/locallang.xlf:tt_content.tx_rssdisplay_numberOfItems</label>
-							<config>
-								<type>input</type>
-								<size>30</size>
-								<eval>int</eval>
-								<default>10</default>
-							</config>
-						</TCEforms>
+						<label>LLL:EXT:rss_display/Resources/Private/Language/locallang.xlf:tt_content.tx_rssdisplay_numberOfItems</label>
+						<config>
+							<type>input</type>
+							<size>30</size>
+							<eval>int</eval>
+							<default>10</default>
+						</config>
 					</settings.numberOfItems>
 					<settings.template>
-						<TCEforms>
-							<label>LLL:EXT:rss_display/Resources/Private/Language/locallang.xlf:tt_content.tx_rssdisplay_template</label>
-							<config>
-								<type>select</type>
-								<itemsProcFunc>Fab\RssDisplay\Backend\FlexformHelper->populateTemplatesList</itemsProcFunc>
-								<renderType>selectSingle</renderType>
-								<items></items>
-							</config>
-						</TCEforms>
+						<label>LLL:EXT:rss_display/Resources/Private/Language/locallang.xlf:tt_content.tx_rssdisplay_template</label>
+						<config>
+							<type>select</type>
+							<itemsProcFunc>Fab\RssDisplay\Backend\FlexformHelper->populateTemplatesList</itemsProcFunc>
+							<renderType>selectSingle</renderType>
+						</config>
 					</settings.template>
 					<!-- @todo add conditional configuration tx_rssdisplay_descriptionlength -->
 				</el>
diff --git a/Configuration/Services.yaml b/Configuration/Services.yaml
new file mode 100644
index 0000000..f32e8dc
--- /dev/null
+++ b/Configuration/Services.yaml
@@ -0,0 +1,12 @@
+services:
+  # general settings
+  _defaults:
+    autowire: true
+    autoconfigure: true
+    public: false
+
+  Fab\RssDisplay\:
+    resource: '../Classes/*'
+
+  Fab\RssDisplay\Controller\FeedController:
+    public: true
\ No newline at end of file
diff --git a/Configuration/Configuration/TCA/Overrides/tt_content.php b/Configuration/TCA/Overrides/tt_content.php
similarity index 94%
rename from Configuration/Configuration/TCA/Overrides/tt_content.php
rename to Configuration/TCA/Overrides/tt_content.php
index 95942b8..6c8c381 100644
--- a/Configuration/Configuration/TCA/Overrides/tt_content.php
+++ b/Configuration/TCA/Overrides/tt_content.php
@@ -1,12 +1,13 @@
 <?php
 
-defined('TYPO3_MODE') or die();
+defined('TYPO3') or die();
 
 \TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
     'rss_display',
     'Pi1',
     'Fetch and display a RSS feed'
 );
+
 \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addPiFlexFormValue('rssdisplay_pi1', 'FILE:EXT:rss_display/Configuration/FlexForm/feed.xml');
 $GLOBALS['TCA']['tt_content']['types']['list']['subtypes_excludelist']['rssdisplay_pi1'] = 'layout, select_key, pages, recursive';
 $GLOBALS['TCA']['tt_content']['types']['list']['subtypes_addlist']['rssdisplay_pi1'] = 'pi_flexform';
diff --git a/Configuration/TsConfig/ContentElementWizard.tsconfig b/Configuration/TsConfig/ContentElementWizard.tsconfig
new file mode 100644
index 0000000..363cf00
--- /dev/null
+++ b/Configuration/TsConfig/ContentElementWizard.tsconfig
@@ -0,0 +1,17 @@
+mod.wizards {
+    newContentElement.wizardItems {
+        plugins {
+            elements {
+                rssdisplay_pi1 {
+                    iconIdentifier = content-widget-rss
+                    title = RSS Feed Display
+                    description = Create a list of rss items
+                    tt_content_defValues {
+                        CType = list
+                        list_type = rssdisplay_pi1
+                    }
+                }
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/Configuration/page.tsconfig b/Configuration/page.tsconfig
new file mode 100644
index 0000000..5e9e96e
--- /dev/null
+++ b/Configuration/page.tsconfig
@@ -0,0 +1 @@
+@import 'EXT:rss_display/Configuration/TsConfig/ContentElementWizard.tsconfig'
\ No newline at end of file
diff --git a/composer.json b/composer.json
index 137f4b1..b286112 100644
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,7 @@
         "issues": "https://github.com/fabarea/rss_display/issues"
     },
     "require": {
-        "typo3/cms-core": "^10.4 || ^11.5",
+        "typo3/cms-core": "^12.4 || ^13.4",
         "simplepie/simplepie": "^1.5"
     },
     "autoload": {
diff --git a/ext_emconf.php b/ext_emconf.php
index 9c67614..477d89e 100644
--- a/ext_emconf.php
+++ b/ext_emconf.php
@@ -11,7 +11,7 @@
     'author_company' => 'Ecodev',
     'constraints' => [
         'depends' => [
-            'typo3' => '10.4.0-11.5.99',
+            'typo3' => '12.4.0-13.4.99',
         ],
     ],
 ];
diff --git a/ext_localconf.php b/ext_localconf.php
index 24d6226..990479d 100644
--- a/ext_localconf.php
+++ b/ext_localconf.php
@@ -1,6 +1,12 @@
 <?php
-if (!defined('TYPO3_MODE')) die ('Access denied.');
-$typo3Version = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(\TYPO3\CMS\Core\Information\Typo3Version::class);
+declare(strict_types=1);
+
+if (!defined('TYPO3')) die ('Access denied.');
+
+
+use Fab\RssDisplay\Controller\FeedController;
+
+
 
 // Define whether USER or USER_INT.
 $pluginType = 'USER_INT';
@@ -26,23 +32,13 @@
 }
 
 // Configure Extbase plugin
-if ($typo3Version->getMajorVersion() >= 11) {
-    \TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
-        'rss_display',
-        'Pi1',
-        [\Fab\RssDisplay\Controller\FeedController::class => 'show'],
-        $pluginType === 'USER_INT' ? [\Fab\RssDisplay\Controller\FeedController::class => 'show'] : [],
-        \TYPO3\CMS\Extbase\Utility\ExtensionUtility::PLUGIN_TYPE_PLUGIN
-    );
-
-} else  {
-    \TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
-        'Fab.rss_display',
-        'Pi1',
-        ['Feed' => 'show'],
-        $pluginType === 'USER_INT' ? ['Feed' => 'show'] : []
-    );
-}
+\TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
+    'rss_display',
+    'Pi1',
+    [FeedController::class => 'show'],
+    $pluginType === 'USER_INT' ? [FeedController::class => 'show'] : [],
+    \TYPO3\CMS\Extbase\Utility\ExtensionUtility::PLUGIN_TYPE_PLUGIN
+);
 
 // cache configuration, see
 // https://docs.typo3.org/typo3cms/CoreApiReference/ApiOverview/CachingFramework/Configuration/Index.html#cache-configurations
diff --git a/ext_tables.php b/ext_tables.php
index 9615237..b3b0f1c 100644
--- a/ext_tables.php
+++ b/ext_tables.php
@@ -1,5 +1,5 @@
 <?php
-if (!defined('TYPO3_MODE')) die ('Access denied.');
+if (!defined('TYPO3')) die ('Access denied.');
 
 
 // Possible Static TS loading
@@ -10,7 +10,6 @@
     \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addStaticFile('rss_display', 'Configuration/TypoScript', 'RSS Display: display a RSS / Atom feed');
 }
 
-$GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['cms']['db_new_content_el']['wizardItemsHook'][\Fab\RssDisplay\Backend\Wizard::class] = \Fab\RssDisplay\Backend\Wizard::class;
 
 call_user_func(function () {
     /**