try CORS 3

Dockerfile

@@ -4,4 +4,4 @@ WORKDIR /app
 COPY . .
 RUN npm ci
 
-CMD ["npx", "serve", "/mnt/media/files", "-c", "/app/serve.json"]
+CMD npx serve --cors /mnt/media/files

serve.json

@@ -1,21 +0,0 @@
-{
-  "headers": [
-    {
-      "source": "*",
-      "headers": [
-        {
-          "key": "Access-Control-Allow-Origin",
-          "value": "*"
-        },
-        {
-          "key": "Access-Control-Allow-Methods",
-          "value": "GET, POST, PUT, DELETE, OPTIONS"
-        },
-        {
-          "key": "Access-Control-Allow-Headers",
-          "value": "Content-Type, Authorization"
-        }
-      ]
-    }
-  ]
-}