1 files changed, 3 insertions, 1 deletions
diff --git a/components/script/dom/response.rs b/components/script/dom/response.rs
index a1226204418..7607cacc972 100644
--- a/components/script/dom/response.rs
+++ b/components/script/dom/response.rs
@@ -298,7 +298,9 @@ impl ResponseMethods for Response {
     // https://fetch.spec.whatwg.org/#dom-response-clone
     fn Clone(&self) -> Fallible<Root<Response>> {
         // Step 1
-        // TODO: This step relies on body and stream, which are still unimplemented.
+        if self.is_locked() || self.body_used.get() {
+            return Err(Error::Type("cannot clone a disturbed response".to_string()));
+        }
 
         // Step 2
         let new_response = Response::new(&self.global());