Hello, first of all excuse me if this is not a BC break or if my code is really bad but the exception / error handling is something I don't master at all.

So in one of my project command, I did this :

$this->getApplication()->setCatchExceptions(false);
$errorHandler = ErrorHandler::register(null, false);
$errorHandler->throwAt(E_ALL, true);
$errorHandler->setExceptionHandler(function () {
	// .... my code
});

to execute something whenever a Symfony command throws an exception or has any error.

In 3.3 and before, if this command throws an exception it goes in my custom exception handler. In 3.4 it doesn't.