### Problem/Motivation `ContentTranslationControllerOverride::overview()` is typed to return `array` and unconditionally passes the parent controller's result to `alterForm()`. Other modules that override the content-translation overview route may return a `Response` from their parent controller (we hit this with a module redirecting the overview to its own translation app). `alterForm()` then fatals on a non-array. ### Proposed resolution Honor a `Response` as-is and only alter render arrays: ```diff - public function overview(RouteMatchInterface $route_match, $entity_type_id = NULL): array { + public function overview(RouteMatchInterface $route_match, $entity_type_id = NULL): array|Response { ... + if (!is_array($build)) { + return $build; + } $this->alterForm($build, $route_match, $entity_type_id); ```