diff --git a/Configuration/TCA/Overrides/sys_template.php b/Configuration/TCA/Overrides/sys_template.php
new file mode 100644
index 0000000000000000000000000000000000000000..2940744c5dd5ec35a4bf5e362bb6580ecca53546
--- /dev/null
+++ b/Configuration/TCA/Overrides/sys_template.php
@@ -0,0 +1,7 @@
+<?php
+
+\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addStaticFile(
+	'sg_youtube',
+	'Configuration/TypoScript',
+	'SG Youtube'
+);
diff --git a/Configuration/TCA/Overrides/tt_content.php b/Configuration/TCA/Overrides/tt_content.php
index 64e24aa43ad2c23ec667bb24885e72a511177c80..c12eb263102d20dd0b4d942104183164def494d9 100644
--- a/Configuration/TCA/Overrides/tt_content.php
+++ b/Configuration/TCA/Overrides/tt_content.php
@@ -4,3 +4,9 @@ $GLOBALS['TCA']['tt_content']['types']['list']['subtypes_addlist']['sgyoutube_yo
 \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addPiFlexFormValue(
 	'sgyoutube_youtube', 'FILE:EXT:sg_youtube/Configuration/FlexForms/flexform_sgyoutube_youtube.xml'
 );
+
+\TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
+	'SGalinski.sg_youtube',
+	'Youtube',
+	'YouTube Videos'
+);
diff --git a/README.md b/README.md
index c9b1d77cee8ec39cbdacef74e45a295fbb657f3c..24e870cd25a0e75757f4a89c281c068cba5c5c1e 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ Repository: https://gitlab.sgalinski.de/typo3/sg_youtube
 
 Please report bugs here: https://gitlab.sgalinski.de/typo3/sg_youtube
 
-TYPO3 version: >8.7
+TYPO3 version: >9.5
 
 ## Installation / Integration
 
diff --git a/UPGRADE.md b/UPGRADE.md
new file mode 100644
index 0000000000000000000000000000000000000000..93c276900d0a58d93347fc195651d02145983279
--- /dev/null
+++ b/UPGRADE.md
@@ -0,0 +1,3 @@
+## Version 4 Breaking Changes
+
+- Dropped TYPO3 8 support
diff --git a/composer.json b/composer.json
index fb0cd64d81486313c0ef02feb4a853b2a162ca0c..c1c18084d388299bb92edccec656fa8733ec6da9 100644
--- a/composer.json
+++ b/composer.json
@@ -4,9 +4,9 @@
   "description": "Embed YouTube Videos of a Playlist or Channel",
   "homepage": "https://www.sgalinski.de",
   "license": "GPL-2.0-or-later",
-  "version": "3.3.0",
+  "version": "4.0.0-dev",
   "require": {
-    "typo3/cms-core": "^8.7.24 || ^9.5.4"
+    "typo3/cms-core": "^9.5.4 || ^10.4.0"
   },
   "require-dev": {
     "roave/security-advisories": "dev-master"
diff --git a/ext_emconf.php b/ext_emconf.php
index f5ed01186fbc2a6b263fa78398830946b89ec38c..803dba5ba0f8c198e6060fe37e61cfaa0df2d346 100644
--- a/ext_emconf.php
+++ b/ext_emconf.php
@@ -24,22 +24,22 @@
  *  This copyright notice MUST APPEAR in all copies of the script!
  ***************************************************************/
 
-$EM_CONF[$_EXTKEY] = [
+$EM_CONF['sg_youtube'] = [
 	'title' => 'YouTube Videos',
 	'description' => 'Embed YouTube Videos of a Channel or Playlist',
 	'category' => 'plugin',
 	'author' => 'Johannes Kreiner',
 	'author_email' => 'johannes@sgalinski.de',
 	'author_company' => 'sgalinski Internet Services (https://www.sgalinski.de)',
-	'state' => 'stable',
+	'state' => 'experimental',
 	'internal' => '',
 	'uploadfolder' => '0',
 	'createDirs' => '',
 	'clearCacheOnLoad' => 0,
-	'version' => '3.3.0',
+	'version' => '4.0.0-dev',
 	'constraints' => [
 		'depends' => [
-			'typo3' => '8.7.0-9.5.99',
+			'typo3' => '9.5.0-10.4.99',
 		],
 		'conflicts' => [],
 		'suggests' => [],
diff --git a/ext_localconf.php b/ext_localconf.php
index 2fb5f10815ab6c0d738d6ef26ecc0d983ee833ee..06603ed2df17dc607fea9a4fc059a35b12cbea7d 100644
--- a/ext_localconf.php
+++ b/ext_localconf.php
@@ -29,7 +29,7 @@ if (!defined('TYPO3_MODE')) {
 }
 
 \TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
-	'SGalinski.' . $_EXTKEY,
+	'SGalinski.sg_youtube',
 	'Youtube',
 	[
 		'Youtube' => 'index',
diff --git a/ext_tables.php b/ext_tables.php
deleted file mode 100644
index fd513be1c21346d532b81a849728576c2bd70260..0000000000000000000000000000000000000000
--- a/ext_tables.php
+++ /dev/null
@@ -1,12 +0,0 @@
-<?php
-if (!defined('TYPO3_MODE')) {
-	die('Access denied.');
-}
-
-\TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
-	'SGalinski.' . $_EXTKEY,
-	'Youtube',
-	'YouTube Videos'
-);
-
-\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addStaticFile($_EXTKEY, 'Configuration/TypoScript', 'SG Youtube');