updated TYPO3 v13 compatibility

Author: Markus Timtner

ext_localconf.php

@@ -4,7 +4,6 @@
 
 $versionInformation = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(\TYPO3\CMS\Core\Information\Typo3Version::class);
 if ($versionInformation->getMajorVersion() > 12) {
-
 	$GLOBALS['TYPO3_CONF_VARS']['BE']['stylesheets']['mt_backend'] = 'EXT:mt_backend/Resources/Public/Css/MyBeTouchup.css';
 
 } else {

ext_tables.php

@@ -1,10 +1,13 @@
 <?php
 defined('TYPO3') || die('Access denied.');
 
-// Custom CSS include
-$GLOBALS['TBE_STYLES']['skins']['mt_backend'] = [
-	'name' => 'mt_backend',
-	'stylesheetDirectories' => [
-		'css' => 'EXT:mt_backend/Resources/Public/Css/'
-	]
-];
+$versionInformation = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(\TYPO3\CMS\Core\Information\Typo3Version::class);
+if ($versionInformation->getMajorVersion() < 13) {
+	// Custom CSS include
+	$GLOBALS['TBE_STYLES']['skins']['mt_backend'] = [
+		'name' => 'mt_backend',
+		'stylesheetDirectories' => [
+			'css' => 'EXT:mt_backend/Resources/Public/Css/'
+		]
+	];
+}