diff --git a/server/app.js b/server/app.js
index 9c774416..a7ae9bc8 100644
--- a/server/app.js
+++ b/server/app.js
@@ -129,7 +129,7 @@ app.use(
       frameSrc: ['*'],
       connectSrc: compact([
         "'self'",
-        process.env.AWS_S3_UPLOAD_BUCKET_URL,
+        process.env.AWS_S3_UPLOAD_BUCKET_URL.replace('s3:', 'localhost:'),
         'www.google-analytics.com',
       ]),
     },