TYPO3 Core

I use Typo 9.5.3.
First thought my Bug would be fixed in #86615
It also seems very similiar to #86616

Same problem here. Changing the order of the middlewares is a possible solution...

return [
    'frontend' => [
        'typo3/cms-redirects/redirecthandler' => [
            'disabled' => true,
        ],
        'hotfix-redirecthandler' => [
            'target' => \TYPO3\CMS\Redirects\Http\Middleware\RedirectHandler::class,
            'before' => [
                'typo3/cms-frontend/base-redirect-resolver',
            ],
        ],
    ],
];

Other solution, add a middleware before "typo3/cms-frontend/base-redirect-resolver"

class SetDefaultLanguage implements MiddlewareInterface
{
    /**
     * @param ServerRequestInterface $request
     * @param RequestHandlerInterface $handler
     * @return ResponseInterface
     */
    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
    {
        $site = $request->getAttribute('site', null);
        $language = $request->getAttribute('language', null);

        if ($site instanceof Site && !($language instanceof SiteLanguage)) {
            $language = $site->getDefaultLanguage();
            $request = $request->withAttribute('language', $language);
        }

        return $handler->handle($request);
    }
}

experienced the same issue on 9.5.8
the workaround with the added middleware did not work for me.

For TYPO3 9 we used the following middleware reordering to workaround this issue for redirects and also static routes:

typo3conf/ext/your_ext/Configuration/RequestMiddlewares.php

<?php

return [
    'frontend' => [
        'typo3/cms-frontend/base-redirect-resolver' => [
            'before' => [
                'typo3/cms-frontend/page-resolver',
            ],
            'after' => [
                'typo3/cms-redirects/redirecthandler',
            ],
        ],
        'typo3/cms-redirects/redirecthandler' => [
            'before' => [
                'typo3/cms-frontend/base-redirect-resolver',
            ],
            'after' => [
                'typo3/cms-frontend/tsfe',
                'typo3/cms-frontend/authentication',
                'typo3/cms-frontend/static-route-resolver',
            ],
        ],
        'typo3/cms-frontend/static-route-resolver' => [
            'before' => [
                'typo3/cms-frontend/base-redirect-resolver',
                'typo3/cms-frontend/page-resolver',
            ],
            'after' => [
                'typo3/cms-frontend/authentication',
            ]
        ],
    ]
];