2 files changed, 9 insertions, 0 deletions
diff --git a/components/script/dom/headers.rs b/components/script/dom/headers.rs
index 5d152ab93bb..b351e2b7f13 100644
--- a/components/script/dom/headers.rs
+++ b/components/script/dom/headers.rs
@@ -234,6 +234,12 @@ impl Headers {
         *self.header_list.borrow_mut() = hyper_headers;
     }
 
+    pub fn get_headers_list(&self) -> HyperHeaders {
+        let mut headers = HyperHeaders::new();
+        headers.extend(self.header_list.borrow_mut().iter());
+        headers
+    }
+
     // https://fetch.spec.whatwg.org/#concept-header-extract-mime-type
     pub fn extract_mime_type(&self) -> Vec<u8> {
         self.header_list.borrow().get_raw("content-type").map_or(vec![], |v| v[0].clone())
diff --git a/components/script/dom/request.rs b/components/script/dom/request.rs
index f0b28f59b69..fcd396c1176 100644
--- a/components/script/dom/request.rs
+++ b/components/script/dom/request.rs
@@ -339,6 +339,9 @@ impl Request {
             _ => {},
         }
 
+        // Copy the headers list onto the headers of net_traits::Request
+        r.request.borrow_mut().headers = r.Headers().get_headers_list();
+
         // Step 32
         let mut input_body = if let RequestInfo::Request(ref input_request) = input {
             let input_request_request = input_request.request.borrow();