fix RSS

src/Controller/Blog/PostController.php

@@ -177,7 +177,12 @@ class PostController extends PageController
             ];
         }
 
-        return $this->json($items);
+        $response = new Response();
+        $response->headers->set('Content-Type', 'text/xml');
+
+        return $this->defaultRender($this->siteRequest->getPage()->getTemplate(), [
+            'items' => $items,
+        ], $response);
     }
 
     public function jsonApi(PostParser $parser): Response