diff --git a/lib/shopify_app/controller_concerns/login_protection.rb b/lib/shopify_app/controller_concerns/login_protection.rb
index 4327df455..05467afa6 100644
--- a/lib/shopify_app/controller_concerns/login_protection.rb
+++ b/lib/shopify_app/controller_concerns/login_protection.rb
@@ -225,9 +225,8 @@ def base_return_address
 
     def return_address_with_params(params)
       uri = URI(base_return_address)
-      uri.query = CGI.parse(uri.query.to_s)
+      uri.query = Rack::Utils.parse_query(uri.query.to_s)
         .symbolize_keys
-        .transform_values { |v| v.one? ? v.first : v }
         .merge(params)
         .to_query
       uri.to_s