diff --git a/components/net/cookie_storage.rs b/components/net/cookie_storage.rs
index 6b79095176d..71eed2ec7ad 100644
--- a/components/net/cookie_storage.rs
+++ b/components/net/cookie_storage.rs
@@ -11,7 +11,7 @@ use net_traits::CookieSource;
 use servo_url::ServoUrl;
 use std::cmp::Ordering;
 
-#[derive(Clone, RustcDecodable, RustcEncodable)]
+#[derive(Clone, Debug, RustcDecodable, RustcEncodable)]
 pub struct CookieStorage {
     version: u32,
     cookies: Vec<Cookie>