asset prefix cannot have "/" at the end

next.config.js

@@ -2,7 +2,7 @@
 const nextConfig = {
   reactStrictMode: true,
   basePath: process.env.APP_PREFIX ? process.env.APP_PREFIX + '/index.html' : '',
-  assetPrefix: process.env.APP_PREFIX ? process.env.APP_PREFIX + '/' : '',
+  assetPrefix: process.env.APP_PREFIX ? process.env.APP_PREFIX : '',
   output: 'export',
   images: {
     unoptimized: true,