Cake 4.0.x redirect and flash with Authorization

Application.php

 <?php
 
 public function middleware(MiddlewareQueue $middlewareQueue): MiddlewareQueue
    {

        $authentication = new AuthenticationMiddleware($this);
        $middlewareQueue
            // Catch any exceptions in the lower layers,
            // and make an error page/response
            ->add(new ErrorHandlerMiddleware(Configure::read('Error')))

            // Handle plugin/theme assets like CakePHP normally does.
            ->add(new AssetMiddleware([
                'cacheTime' => Configure::read('Asset.cacheTime'),
            ]))

            // Add routing middleware.
            // If you have a large number of routes connected, turning on routes
            // caching in production could improve performance. For that when
            // creating the middleware instance specify the cache config name by
            // using it's second constructor argument:
            // `new RoutingMiddleware($this, '_cake_routes_')`
            ->add(new RoutingMiddleware($this))
            ->add($authentication)
            ->add(new AuthorizationMiddleware($this, [
                'unauthorizedHandler' => [
                    'className' => 'CustomRedirect',
                    'url' => ['_name' => 'login'],
                    'queryParams' => 'redirectUrl',
                    'flash' => [
                        'message' => 'coucou',
                        'key' => 'flash',
                        'element' => 'flash/error'
                    ]
                ]
            ]))
            ->add(new RequestAuthorizationMiddleware());

        return $middlewareQueue;
    }

CustomRedirectHandler.php

<?php
declare(strict_types=1);

namespace App\Middleware\UnauthorizedHandler;

use Authorization\Exception\Exception;
use Authorization\Exception\ForbiddenException;
use Authorization\Exception\MissingIdentityException;
use Authorization\Middleware\UnauthorizedHandler\CakeRedirectHandler;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;

class CustomRedirectHandler extends CakeRedirectHandler
{
    /**
     * @inheritDoc
     */
    protected $defaultOptions = [
        'exceptions' => [
            MissingIdentityException::class,
            ForbiddenException::class
        ],
        'url' => [
            'controller' => 'Users',
            'action' => 'login',
        ],
        'queryParam' => 'redirect',
        'statusCode' => 302,
    ];

    public function handle(Exception $exception, ServerRequestInterface $request, array $options = []): ResponseInterface
    {
        $session = $request->getSession();
        $session->write('Flash.' . $options['flash']['key'], [[
            'message' => $options['flash']['message'],
            'key' => $options['flash']['key'],
            'element' => $options['flash']['element']
        ]]);
        return parent::handle($exception, $request, $options); // TODO: Change the autogenerated stub
    }
}