[BUGFIX] Fix missing extension key for addPlugin

Configuration/TCA/Overrides/tt_content.php

@@ -32,7 +32,8 @@ call_user_func(function ($extKey) {
 			$extKey . '_plugin1',
 			'EXT:' . $extKey . '/Resources/Public/Images/contentElementWizard.png'
 		),
-		'list_type'
+		'list_type',
+		$extKey
 	);
 }, 'df_tabs');