diff --git a/src/common/core/ui/confs/default-server-http/ui.conf b/src/common/core/ui/confs/default-server-http/ui.conf
index 78028ea1a..8a9bb2454 100644
--- a/src/common/core/ui/confs/default-server-http/ui.conf
+++ b/src/common/core/ui/confs/default-server-http/ui.conf
@@ -65,6 +65,9 @@ location /setup {
     proxy_buffering on;
 
     # Response body modifications
+    header_filter_by_luea_block {
+        ngx.header.content_length = nil
+    }
     body_filter_by_lua_block {
         local str = ngx.arg[1]
         local patterns = {