The \Magento\Theme\Model\Theme\Plugin\Registration::beforeDispatch() method can be simplified by removing the unused $subject and $request arguments

This can be simplified to:

 * Add new theme from filesystem and update existing
 * @return void
public function beforeDispatch() {
	try {
		if ($this->appState->getMode() != AppState::MODE_PRODUCTION) {
	} catch (LocalizedException $e) {

A trick: a «before» plugin can avoid declaration of unused last arguments if it needs not modify any argument