Make url for "client" referrer mandatory

37 files changed, 409 insertions, 213 deletions

diff --git a/components/constellation/constellation.rs b/components/constellation/constellation.rs
index 1106325a1a9..cfca54e8da5 100644
--- a/components/constellation/constellation.rs
+++ b/components/constellation/constellation.rs
@@ -136,7 +136,7 @@ use msg::constellation_msg::{
     TopLevelBrowsingContextId,
 };
 use net_traits::pub_domains::reg_host;
-use net_traits::request::RequestBuilder;
+use net_traits::request::{Referrer, RequestBuilder};
 use net_traits::storage_thread::{StorageThreadMsg, StorageType};
 use net_traits::{self, FetchResponseMsg, IpcSend, ResourceThreads};
 use profile_traits::mem;
@@ -1544,7 +1544,13 @@ where
             // If there is already a pending page (self.pending_changes), it will not be overridden;
             // However, if the id is not encompassed by another change, it will be.
             FromCompositorMsg::LoadUrl(top_level_browsing_context_id, url) => {
-                let load_data = LoadData::new(LoadOrigin::Constellation, url, None, None, None);
+                let load_data = LoadData::new(
+                    LoadOrigin::Constellation,
+                    url,
+                    None,
+                    Referrer::NoReferrer,
+                    None,
+                );
                 let ctx_id = BrowsingContextId::from(top_level_browsing_context_id);
                 let pipeline_id = match self.browsing_contexts.get(&ctx_id) {
                     Some(ctx) => ctx.pipeline_id,
@@ -2888,7 +2894,13 @@ where
         warn!("creating replacement pipeline for about:failure");
 
         let new_pipeline_id = PipelineId::new();
-        let load_data = LoadData::new(LoadOrigin::Constellation, failure_url, None, None, None);
+        let load_data = LoadData::new(
+            LoadOrigin::Constellation,
+            failure_url,
+            None,
+            Referrer::NoReferrer,
+            None,
+        );
         let sandbox = IFrameSandboxState::IFrameSandboxed;
         let is_private = false;
         self.new_pipeline(
@@ -2998,7 +3010,13 @@ where
         );
         self.embedder_proxy.send(msg);
         let browsing_context_id = BrowsingContextId::from(top_level_browsing_context_id);
-        let load_data = LoadData::new(LoadOrigin::Constellation, url, None, None, None);
+        let load_data = LoadData::new(
+            LoadOrigin::Constellation,
+            url,
+            None,
+            Referrer::NoReferrer,
+            None,
+        );
         let sandbox = IFrameSandboxState::IFrameUnsandboxed;
         let is_private = false;
         let is_visible = true;
diff --git a/components/constellation/network_listener.rs b/components/constellation/network_listener.rs
index ccbe00d4940..ec962b42f17 100644
--- a/components/constellation/network_listener.rs
+++ b/components/constellation/network_listener.rs
@@ -116,7 +116,8 @@ impl NetworkListener {
                         self.request_builder.referrer = metadata
                             .referrer
                             .clone()
-                            .map(|referrer_url| Referrer::ReferrerUrl(referrer_url));
+                            .map(|referrer_url| Referrer::ReferrerUrl(referrer_url))
+                            .unwrap_or(Referrer::NoReferrer);
                         self.request_builder.referrer_policy = metadata.referrer_policy;
 
                         let headers = if let Some(ref headers) = metadata.headers {
diff --git a/components/gfx/font_cache_thread.rs b/components/gfx/font_cache_thread.rs
index 21771b151da..866d3c68cfd 100644
--- a/components/gfx/font_cache_thread.rs
+++ b/components/gfx/font_cache_thread.rs
@@ -14,7 +14,7 @@ use crate::platform::font_template::FontTemplateData;
 use app_units::Au;
 use gfx_traits::{FontData, WebrenderApi};
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
-use net_traits::request::{Destination, RequestBuilder};
+use net_traits::request::{Destination, Referrer, RequestBuilder};
 use net_traits::{fetch_async, CoreResourceThread, FetchResponseMsg};
 use servo_atoms::Atom;
 use servo_url::ServoUrl;
@@ -235,7 +235,10 @@ impl FontCache {
                     None => return,
                 };
 
-                let request = RequestBuilder::new(url.clone()).destination(Destination::Font);
+                // FIXME:
+                // This shouldn't use NoReferrer, but the current documents url
+                let request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
+                    .destination(Destination::Font);
 
                 let channel_to_self = self.channel_to_self.clone();
                 let bytes = Mutex::new(Vec::new());
diff --git a/components/net/fetch/methods.rs b/components/net/fetch/methods.rs
index 1aabb545354..41b804fb7fc 100644
--- a/components/net/fetch/methods.rs
+++ b/components/net/fetch/methods.rs
@@ -239,13 +239,7 @@ pub fn main_fetch(
     {
         let referrer_url = match mem::replace(&mut request.referrer, Referrer::NoReferrer) {
             Referrer::NoReferrer => None,
-            Referrer::Client => {
-                // FIXME(#14507): We should never get this value here; it should
-                //                already have been handled in the script thread.
-                request.headers.remove(header::REFERER);
-                None
-            },
-            Referrer::ReferrerUrl(url) => {
+            Referrer::ReferrerUrl(url) | Referrer::Client(url) => {
                 request.headers.remove(header::REFERER);
                 let current_url = request.current_url();
                 determine_request_referrer(
diff --git a/components/net/http_loader.rs b/components/net/http_loader.rs
index 33a6e4415e3..eaed2ff1989 100644
--- a/components/net/http_loader.rs
+++ b/components/net/http_loader.rs
@@ -1141,7 +1141,8 @@ fn http_network_or_cache_fetch(
     // Step 5.9
     match http_request.referrer {
         Referrer::NoReferrer => (),
-        Referrer::ReferrerUrl(ref http_request_referrer) => {
+        Referrer::ReferrerUrl(ref http_request_referrer) |
+        Referrer::Client(ref http_request_referrer) => {
             if let Ok(referer) = http_request_referrer.to_string().parse::<Referer>() {
                 http_request.headers.typed_insert(referer);
             } else {
@@ -1151,12 +1152,6 @@ fn http_network_or_cache_fetch(
                 error!("Failed to parse {} as referer", http_request_referrer);
             }
         },
-        Referrer::Client =>
-        // it should be impossible for referrer to be anything else during fetching
-        // https://fetch.spec.whatwg.org/#concept-request-referrer
-        {
-            unreachable!()
-        },
     };
 
     // Step 5.10
@@ -1938,7 +1933,7 @@ fn cors_preflight_fetch(
     context: &FetchContext,
 ) -> Response {
     // Step 1
-    let mut preflight = RequestBuilder::new(request.current_url())
+    let mut preflight = RequestBuilder::new(request.current_url(), request.referrer.clone())
         .method(Method::OPTIONS)
         .origin(match &request.origin {
             Origin::Client => {
@@ -1949,7 +1944,6 @@ fn cors_preflight_fetch(
         .pipeline_id(request.pipeline_id)
         .initiator(request.initiator.clone())
         .destination(request.destination.clone())
-        .referrer(Some(request.referrer.clone()))
         .referrer_policy(request.referrer_policy)
         .build();
 
diff --git a/components/net/tests/data_loader.rs b/components/net/tests/data_loader.rs
index 3e7cde682f4..aa985a17d2b 100644
--- a/components/net/tests/data_loader.rs
+++ b/components/net/tests/data_loader.rs
@@ -6,7 +6,7 @@ use crate::fetch;
 use headers::{ContentType, HeaderMapExt};
 use hyper_serde::Serde;
 use mime::{self, Mime};
-use net_traits::request::{Origin, Request};
+use net_traits::request::{Origin, Referrer, Request};
 use net_traits::response::{HttpsState, ResponseBody};
 use net_traits::{FetchMetadata, FilteredMetadata, NetworkError};
 use servo_url::ServoUrl;
@@ -21,7 +21,13 @@ fn assert_parse(
 ) {
     let url = ServoUrl::parse(url).unwrap();
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
 
     let response = fetch(&mut request, None);
 
diff --git a/components/net/tests/fetch.rs b/components/net/tests/fetch.rs
index dc4c0f032c0..821e81a00c2 100644
--- a/components/net/tests/fetch.rs
+++ b/components/net/tests/fetch.rs
@@ -59,8 +59,13 @@ fn test_fetch_response_is_not_network_error() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     let fetch_response = fetch(&mut request, None);
     let _ = server.close();
 
@@ -73,8 +78,13 @@ fn test_fetch_response_is_not_network_error() {
 fn test_fetch_on_bad_port_is_network_error() {
     let url = ServoUrl::parse("http://www.example.org:6667").unwrap();
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     let fetch_response = fetch(&mut request, None);
     assert!(fetch_response.is_network_error());
     let fetch_error = fetch_response.get_network_error().unwrap();
@@ -93,8 +103,13 @@ fn test_fetch_response_body_matches_const_message() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     let fetch_response = fetch(&mut request, None);
     let _ = server.close();
 
@@ -113,8 +128,13 @@ fn test_fetch_response_body_matches_const_message() {
 fn test_fetch_aboutblank() {
     let url = ServoUrl::parse("about:blank").unwrap();
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
 
     let fetch_response = fetch(&mut request, None);
     // We should see an opaque-filtered response.
@@ -177,6 +197,7 @@ fn test_fetch_blob() {
     let mut request = Request::new(
         url,
         Some(Origin::Origin(origin.origin())),
+        Referrer::NoReferrer,
         None,
         HttpsState::None,
     );
@@ -220,7 +241,13 @@ fn test_file() {
     let url = ServoUrl::from_file_path(path.clone()).unwrap();
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
 
     let pool = CoreResourceThreadPool::new(1);
     let pool_handle = Arc::new(pool);
@@ -262,8 +289,13 @@ fn test_file() {
 fn test_fetch_ftp() {
     let url = ServoUrl::parse("ftp://not-supported").unwrap();
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     let fetch_response = fetch(&mut request, None);
     assert!(fetch_response.is_network_error());
 }
@@ -272,8 +304,13 @@ fn test_fetch_ftp() {
 fn test_fetch_bogus_scheme() {
     let url = ServoUrl::parse("bogus://whatever").unwrap();
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     let fetch_response = fetch(&mut request, None);
     assert!(fetch_response.is_network_error());
 }
@@ -319,8 +356,13 @@ fn test_cors_preflight_fetch() {
     let target_url = url.clone().join("a.html").unwrap();
 
     let origin = Origin::Origin(ImmutableOrigin::new_opaque());
-    let mut request = Request::new(url.clone(), Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::ReferrerUrl(target_url);
+    let mut request = Request::new(
+        url.clone(),
+        Some(origin),
+        Referrer::ReferrerUrl(target_url),
+        None,
+        HttpsState::None,
+    );
     request.referrer_policy = Some(ReferrerPolicy::Origin);
     request.use_cors_preflight = true;
     request.mode = RequestMode::CorsMode;
@@ -371,8 +413,13 @@ fn test_cors_preflight_cache_fetch() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(ImmutableOrigin::new_opaque());
-    let mut request = Request::new(url.clone(), Some(origin.clone()), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url.clone(),
+        Some(origin.clone()),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     request.use_cors_preflight = true;
     request.mode = RequestMode::CorsMode;
     let mut wrapped_request0 = request.clone();
@@ -433,9 +480,14 @@ fn test_cors_preflight_fetch_network_error() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(ImmutableOrigin::new_opaque());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     request.method = Method::from_bytes(b"CHICKEN").unwrap();
-    request.referrer = Referrer::NoReferrer;
     request.use_cors_preflight = true;
     request.mode = RequestMode::CorsMode;
     let fetch_response = fetch(&mut request, None);
@@ -462,8 +514,13 @@ fn test_fetch_response_is_basic_filtered() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     let fetch_response = fetch(&mut request, None);
     let _ = server.close();
 
@@ -525,8 +582,13 @@ fn test_fetch_response_is_cors_filtered() {
 
     // an origin mis-match will stop it from defaulting to a basic filtered response
     let origin = Origin::Origin(ImmutableOrigin::new_opaque());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     request.mode = RequestMode::CorsMode;
     let fetch_response = fetch(&mut request, None);
     let _ = server.close();
@@ -559,8 +621,13 @@ fn test_fetch_response_is_opaque_filtered() {
 
     // an origin mis-match will fall through to an Opaque filtered response
     let origin = Origin::Origin(ImmutableOrigin::new_opaque());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     let fetch_response = fetch(&mut request, None);
     let _ = server.close();
 
@@ -607,8 +674,13 @@ fn test_fetch_response_is_opaque_redirect_filtered() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     request.redirect_mode = RedirectMode::Manual;
     let fetch_response = fetch(&mut request, None);
     let _ = server.close();
@@ -641,8 +713,13 @@ fn test_fetch_with_local_urls_only() {
 
     let do_fetch = |url: ServoUrl| {
         let origin = Origin::Origin(url.origin());
-        let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-        request.referrer = Referrer::NoReferrer;
+        let mut request = Request::new(
+            url,
+            Some(origin),
+            Referrer::NoReferrer,
+            None,
+            HttpsState::None,
+        );
 
         // Set the flag.
         request.local_urls_only = true;
@@ -708,8 +785,13 @@ fn test_fetch_with_hsts() {
         );
     }
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     // Set the flag.
     request.local_urls_only = false;
     let response = fetch_with_context(&mut request, &mut context);
@@ -759,7 +841,7 @@ fn test_load_adds_host_to_hsts_list_when_url_is_https() {
         ))),
     };
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -824,7 +906,7 @@ fn test_fetch_self_signed() {
         ))),
     };
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -850,7 +932,7 @@ fn test_fetch_self_signed() {
     let (server, mut url) = make_ssl_server(handler, cert_path.clone(), key_path.clone());
     url.as_mut_url().set_scheme("https").unwrap();
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -874,8 +956,13 @@ fn test_fetch_with_sri_network_error() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     // To calulate hash use :
     // echo -n "alert('Hello, Network Error');" | openssl dgst -sha384 -binary | openssl base64 -A
     request.integrity_metadata =
@@ -898,8 +985,13 @@ fn test_fetch_with_sri_sucess() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     // To calulate hash use :
     // echo -n "alert('Hello, Network Error');" | openssl dgst -sha384 -binary | openssl base64 -A
     request.integrity_metadata =
@@ -938,7 +1030,13 @@ fn test_fetch_blocked_nosniff() {
         let (server, url) = make_server(handler);
 
         let origin = Origin::Origin(url.origin());
-        let mut request = Request::new(url, Some(origin), None, HttpsState::None);
+        let mut request = Request::new(
+            url,
+            Some(origin),
+            Referrer::NoReferrer,
+            None,
+            HttpsState::None,
+        );
         request.destination = destination;
         let fetch_response = fetch(&mut request, None);
         let _ = server.close();
@@ -982,8 +1080,13 @@ fn setup_server_and_fetch(message: &'static [u8], redirect_cap: u32) -> Response
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     let fetch_response = fetch(&mut request, None);
     let _ = server.close();
     fetch_response
@@ -1070,8 +1173,13 @@ fn test_fetch_redirect_updates_method_runner(
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     request.method = method;
 
     let _ = fetch(&mut request, None);
@@ -1153,8 +1261,13 @@ fn test_fetch_async_returns_complete_response() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
 
     let fetch_response = fetch(&mut request, None);
 
@@ -1172,8 +1285,13 @@ fn test_opaque_filtered_fetch_async_returns_complete_response() {
 
     // an origin mis-match will fall through to an Opaque filtered response
     let origin = Origin::Origin(ImmutableOrigin::new_opaque());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
 
     let fetch_response = fetch(&mut request, None);
 
@@ -1208,8 +1326,13 @@ fn test_opaque_redirect_filtered_fetch_async_returns_complete_response() {
     let (server, url) = make_server(handler);
 
     let origin = Origin::Origin(url.origin());
-    let mut request = Request::new(url, Some(origin), None, HttpsState::None);
-    request.referrer = Referrer::NoReferrer;
+    let mut request = Request::new(
+        url,
+        Some(origin),
+        Referrer::NoReferrer,
+        None,
+        HttpsState::None,
+    );
     request.redirect_mode = RedirectMode::Manual;
 
     let fetch_response = fetch(&mut request, None);
@@ -1233,10 +1356,10 @@ fn test_fetch_with_devtools() {
     let mut request = Request::new(
         url.clone(),
         Some(origin),
+        Referrer::NoReferrer,
         Some(TEST_PIPELINE_ID),
         HttpsState::None,
     );
-    request.referrer = Referrer::NoReferrer;
 
     let (devtools_chan, devtools_port) = unbounded();
 
diff --git a/components/net/tests/http_cache.rs b/components/net/tests/http_cache.rs
index c56f4c59d72..6d2cd50ce47 100644
--- a/components/net/tests/http_cache.rs
+++ b/components/net/tests/http_cache.rs
@@ -7,7 +7,7 @@ use http::header::{HeaderValue, EXPIRES};
 use http::StatusCode;
 use msg::constellation_msg::TEST_PIPELINE_ID;
 use net::http_cache::HttpCache;
-use net_traits::request::{Origin, Request};
+use net_traits::request::{Origin, Referrer, Request};
 use net_traits::response::{HttpsState, Response, ResponseBody};
 use net_traits::{ResourceFetchTiming, ResourceTimingType};
 use servo_url::ServoUrl;
@@ -23,6 +23,7 @@ fn test_refreshing_resource_sets_done_chan_the_appropriate_value() {
     let request = Request::new(
         url.clone(),
         Some(Origin::Origin(url.clone().origin())),
+        Referrer::NoReferrer,
         Some(TEST_PIPELINE_ID),
         HttpsState::None,
     );
diff --git a/components/net/tests/http_loader.rs b/components/net/tests/http_loader.rs
index 48f18560d54..f5b5a82cb5a 100644
--- a/components/net/tests/http_loader.rs
+++ b/components/net/tests/http_loader.rs
@@ -33,7 +33,7 @@ use net::http_loader::determine_request_referrer;
 use net::resource_thread::AuthCacheEntry;
 use net::test::replace_host_table;
 use net_traits::request::{
-    BodyChunkRequest, BodyChunkResponse, BodySource, CredentialsMode, Destination, RequestBody,
+    BodyChunkRequest, BodyChunkResponse, BodySource, CredentialsMode, Destination, RequestBody, Referrer
     RequestBuilder, RequestMode,
 };
 use net_traits::response::{HttpsState, ResponseBody};
@@ -159,7 +159,7 @@ fn test_check_default_headers_loaded_in_every_request() {
     *expected_headers.lock().unwrap() = Some(headers.clone());
 
     // Testing for method.GET
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .destination(Destination::Document)
         .origin(url.clone().origin())
@@ -186,7 +186,7 @@ fn test_check_default_headers_loaded_in_every_request() {
         HeaderValue::from_str(&url_str[..url_str.len() - 1]).unwrap(),
     );
     *expected_headers.lock().unwrap() = Some(post_headers);
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::POST)
         .destination(Destination::Document)
         .origin(url.clone().origin())
@@ -216,7 +216,7 @@ fn test_load_when_request_is_not_get_or_head_and_there_is_no_body_content_length
     };
     let (server, url) = make_server(handler);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::POST)
         .body(None)
         .destination(Destination::Document)
@@ -248,7 +248,7 @@ fn test_request_and_response_data_with_network_messages() {
 
     let mut request_headers = HeaderMap::new();
     request_headers.typed_insert(Host::from("bar.foo".parse::<Authority>().unwrap()));
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .headers(request_headers)
         .body(None)
@@ -343,7 +343,7 @@ fn test_request_and_response_message_from_devtool_without_pipeline_id() {
     };
     let (server, url) = make_server(handler);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .destination(Destination::Document)
         .origin(mock_origin())
@@ -385,7 +385,7 @@ fn test_redirected_request_to_devtools() {
     };
     let (pre_server, pre_url) = make_server(pre_handler);
 
-    let mut request = RequestBuilder::new(pre_url.clone())
+    let mut request = RequestBuilder::new(pre_url.clone(), Referrer::NoReferrer)
         .method(Method::POST)
         .destination(Destination::Document)
         .pipeline_id(Some(TEST_PIPELINE_ID))
@@ -434,7 +434,7 @@ fn test_load_when_redirecting_from_a_post_should_rewrite_next_request_as_get() {
     };
     let (pre_server, pre_url) = make_server(pre_handler);
 
-    let mut request = RequestBuilder::new(pre_url.clone())
+    let mut request = RequestBuilder::new(pre_url.clone(), Referrer::NoReferrer)
         .method(Method::POST)
         .destination(Destination::Document)
         .origin(mock_origin())
@@ -464,7 +464,7 @@ fn test_load_should_decode_the_response_as_deflate_when_response_headers_have_co
     };
     let (server, url) = make_server(handler);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -497,7 +497,7 @@ fn test_load_should_decode_the_response_as_gzip_when_response_headers_have_conte
     };
     let (server, url) = make_server(handler);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -552,7 +552,7 @@ fn test_load_doesnt_send_request_body_on_any_redirect() {
     let content = b"Body on POST!";
     let request_body = create_request_body_with_content(content.to_vec());
 
-    let mut request = RequestBuilder::new(pre_url.clone())
+    let mut request = RequestBuilder::new(pre_url.clone(), Referrer::NoReferrer)
         .body(Some(request_body))
         .method(Method::POST)
         .destination(Destination::Document)
@@ -580,7 +580,7 @@ fn test_load_doesnt_add_host_to_hsts_list_when_url_is_http_even_if_hsts_headers_
     };
     let (server, url) = make_server(handler);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -626,7 +626,7 @@ fn test_load_sets_cookies_in_the_resource_manager_when_it_get_set_cookie_header_
 
     assert_cookie_for_domain(&context.state.cookie_jar, url.as_str(), None);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -678,7 +678,7 @@ fn test_load_sets_requests_cookies_header_for_url_by_getting_cookies_from_the_re
         cookie_jar.push(cookie, &url, CookieSource::HTTP);
     }
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -724,7 +724,7 @@ fn test_load_sends_cookie_if_nonhttp() {
         cookie_jar.push(cookie, &url, CookieSource::HTTP);
     }
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -761,7 +761,7 @@ fn test_cookie_set_with_httponly_should_not_be_available_using_getcookiesforurl(
 
     assert_cookie_for_domain(&context.state.cookie_jar, url.as_str(), None);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -808,7 +808,7 @@ fn test_when_cookie_received_marked_secure_is_ignored_for_http() {
 
     assert_cookie_for_domain(&context.state.cookie_jar, url.as_str(), None);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -847,7 +847,7 @@ fn test_load_sets_content_length_to_length_of_request_body() {
 
     let request_body = create_request_body_with_content(content.to_vec());
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::POST)
         .body(Some(request_body))
         .destination(Destination::Document)
@@ -886,7 +886,7 @@ fn test_load_uses_explicit_accept_from_headers_in_load_data() {
 
     let mut accept_headers = HeaderMap::new();
     accept_headers.insert(header::ACCEPT, HeaderValue::from_static("text/html"));
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .headers(accept_headers)
         .destination(Destination::Document)
@@ -923,7 +923,7 @@ fn test_load_sets_default_accept_to_html_xhtml_xml_and_then_anything_else() {
     };
     let (server, url) = make_server(handler);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .destination(Destination::Document)
         .origin(mock_origin())
@@ -961,7 +961,7 @@ fn test_load_uses_explicit_accept_encoding_from_load_data_headers() {
 
     let mut accept_encoding_headers = HeaderMap::new();
     accept_encoding_headers.insert(header::ACCEPT_ENCODING, HeaderValue::from_static("chunked"));
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .headers(accept_encoding_headers)
         .destination(Destination::Document)
@@ -998,7 +998,7 @@ fn test_load_sets_default_accept_encoding_to_gzip_and_deflate() {
     };
     let (server, url) = make_server(handler);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .destination(Destination::Document)
         .origin(mock_origin())
@@ -1051,7 +1051,7 @@ fn test_load_errors_when_there_a_redirect_loop() {
 
     *url_b_for_a.lock().unwrap() = Some(url_b.clone());
 
-    let mut request = RequestBuilder::new(url_a.clone())
+    let mut request = RequestBuilder::new(url_a.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .destination(Destination::Document)
         .origin(mock_origin())
@@ -1107,7 +1107,7 @@ fn test_load_succeeds_with_a_redirect_loop() {
 
     *url_b_for_a.lock().unwrap() = Some(url_b.clone());
 
-    let mut request = RequestBuilder::new(url_a.clone())
+    let mut request = RequestBuilder::new(url_a.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .destination(Destination::Document)
         .origin(mock_origin())
@@ -1146,7 +1146,7 @@ fn test_load_follows_a_redirect() {
     };
     let (pre_server, pre_url) = make_server(pre_handler);
 
-    let mut request = RequestBuilder::new(pre_url.clone())
+    let mut request = RequestBuilder::new(pre_url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .destination(Destination::Document)
         .origin(mock_origin())
@@ -1229,7 +1229,7 @@ fn test_redirect_from_x_to_y_provides_y_cookies_from_y() {
         cookie_jar.push(cookie_y, &url_y, CookieSource::HTTP);
     }
 
-    let mut request = RequestBuilder::new(url_x.clone())
+    let mut request = RequestBuilder::new(url_x.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .destination(Destination::Document)
         .origin(mock_origin())
@@ -1278,7 +1278,7 @@ fn test_redirect_from_x_to_x_provides_x_with_cookie_from_first_response() {
 
     let url = url.join("/initial/").unwrap();
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .destination(Destination::Document)
         .origin(mock_origin())
@@ -1309,7 +1309,7 @@ fn test_if_auth_creds_not_in_url_but_in_cache_it_sets_it() {
     };
     let (server, url) = make_server(handler);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -1353,7 +1353,7 @@ fn test_auth_ui_needs_www_auth() {
     };
     let (server, url) = make_server(handler);
 
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .body(None)
         .destination(Destination::Document)
@@ -1390,7 +1390,7 @@ fn test_origin_set() {
     let mut origin =
         Origin::try_from_parts(url.scheme(), url.host_str().unwrap(), url.port()).unwrap();
     *origin_header_clone.lock().unwrap() = Some(origin.clone());
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::POST)
         .body(None)
         .origin(url.clone().origin())
@@ -1409,7 +1409,7 @@ fn test_origin_set() {
     origin =
         Origin::try_from_parts(origin_url.scheme(), origin_url.host_str().unwrap(), None).unwrap();
     // Test Origin header is set on Get request with CORS mode
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::GET)
         .mode(RequestMode::CorsMode)
         .body(None)
@@ -1427,7 +1427,7 @@ fn test_origin_set() {
         .is_success());
 
     // Test Origin header is not set on method Head
-    let mut request = RequestBuilder::new(url.clone())
+    let mut request = RequestBuilder::new(url.clone(), Referrer::NoReferrer)
         .method(Method::HEAD)
         .body(None)
         .origin(url.clone().origin())
diff --git a/components/net_traits/request.rs b/components/net_traits/request.rs
index c15063c7a70..cc67ca0cd27 100644
--- a/components/net_traits/request.rs
+++ b/components/net_traits/request.rs
@@ -37,8 +37,12 @@ pub enum Origin {
 #[derive(Clone, Debug, Deserialize, MallocSizeOf, PartialEq, Serialize)]
 pub enum Referrer {
     NoReferrer,
-    /// Default referrer if nothing is specified
-    Client,
+    /// Contains the url that "client" would be resolved to. See
+    /// [https://w3c.github.io/webappsec-referrer-policy/#determine-requests-referrer](https://w3c.github.io/webappsec-referrer-policy/#determine-requests-referrer)
+    ///
+    /// If you are unsure you should probably use
+    /// [`GlobalScope::get_referrer`](https://doc.servo.org/script/dom/globalscope/struct.GlobalScope.html#method.get_referrer)
+    Client(ServoUrl),
     ReferrerUrl(ServoUrl),
 }
 
@@ -231,7 +235,7 @@ pub struct RequestBuilder {
     pub use_url_credentials: bool,
     pub origin: ImmutableOrigin,
     // XXXManishearth these should be part of the client object
-    pub referrer: Option<Referrer>,
+    pub referrer: Referrer,
     pub referrer_policy: Option<ReferrerPolicy>,
     pub pipeline_id: Option<PipelineId>,
     pub redirect_mode: RedirectMode,
@@ -249,7 +253,7 @@ pub struct RequestBuilder {
 }
 
 impl RequestBuilder {
-    pub fn new(url: ServoUrl) -> RequestBuilder {
+    pub fn new(url: ServoUrl, referrer: Referrer) -> RequestBuilder {
         RequestBuilder {
             method: Method::GET,
             url: url,
@@ -265,7 +269,7 @@ impl RequestBuilder {
             credentials_mode: CredentialsMode::Omit,
             use_url_credentials: false,
             origin: ImmutableOrigin::new_opaque(),
-            referrer: None,
+            referrer: referrer,
             referrer_policy: None,
             pipeline_id: None,
             redirect_mode: RedirectMode::Follow,
@@ -338,11 +342,6 @@ impl RequestBuilder {
         self
     }
 
-    pub fn referrer(mut self, referrer: Option<Referrer>) -> RequestBuilder {
-        self.referrer = referrer;
-        self
-    }
-
     pub fn referrer_policy(mut self, referrer_policy: Option<ReferrerPolicy>) -> RequestBuilder {
         self.referrer_policy = referrer_policy;
         self
@@ -377,6 +376,7 @@ impl RequestBuilder {
         let mut request = Request::new(
             self.url.clone(),
             Some(Origin::Origin(self.origin)),
+            self.referrer,
             self.pipeline_id,
             self.https_state,
         );
@@ -393,7 +393,6 @@ impl RequestBuilder {
         request.credentials_mode = self.credentials_mode;
         request.use_url_credentials = self.use_url_credentials;
         request.cache_mode = self.cache_mode;
-        request.referrer = self.referrer.unwrap_or(Referrer::Client);
         request.referrer_policy = self.referrer_policy;
         request.redirect_mode = self.redirect_mode;
         let mut url_list = self.url_list;
@@ -484,6 +483,7 @@ impl Request {
     pub fn new(
         url: ServoUrl,
         origin: Option<Origin>,
+        referrer: Referrer,
         pipeline_id: Option<PipelineId>,
         https_state: HttpsState,
     ) -> Request {
@@ -500,7 +500,7 @@ impl Request {
             initiator: Initiator::None,
             destination: Destination::None,
             origin: origin.unwrap_or(Origin::Client),
-            referrer: Referrer::Client,
+            referrer: referrer,
             referrer_policy: None,
             pipeline_id: pipeline_id,
             synchronous: false,
@@ -569,7 +569,8 @@ impl Request {
 impl Referrer {
     pub fn to_url(&self) -> Option<&ServoUrl> {
         match *self {
-            Referrer::NoReferrer | Referrer::Client => None,
+            Referrer::NoReferrer => None,
+            Referrer::Client(ref url) => Some(url),
             Referrer::ReferrerUrl(ref url) => Some(url),
         }
     }
diff --git a/components/script/dom/dedicatedworkerglobalscope.rs b/components/script/dom/dedicatedworkerglobalscope.rs
index c764678b80a..0095429b571 100644
--- a/components/script/dom/dedicatedworkerglobalscope.rs
+++ b/components/script/dom/dedicatedworkerglobalscope.rs
@@ -330,6 +330,7 @@ impl DedicatedWorkerGlobalScope {
         let top_level_browsing_context_id = TopLevelBrowsingContextId::installed();
         let current_global = GlobalScope::current().expect("No current global object");
         let origin = current_global.origin().immutable().clone();
+        let referrer = current_global.get_referrer();
         let parent = current_global.runtime_handle();
         let current_global_https_state = current_global.get_https_state();
 
@@ -351,16 +352,17 @@ impl DedicatedWorkerGlobalScope {
                     pipeline_id,
                 } = worker_load_origin;
 
-                let referrer = referrer_url.map(|referrer_url| Referrer::ReferrerUrl(referrer_url));
+                let referrer = referrer_url
+                    .map(|url| Referrer::ReferrerUrl(url))
+                    .unwrap_or(referrer);
 
-                let request = RequestBuilder::new(worker_url.clone())
+                let request = RequestBuilder::new(worker_url.clone(), referrer)
                     .destination(Destination::Worker)
                     .mode(RequestMode::SameOrigin)
                     .credentials_mode(CredentialsMode::CredentialsSameOrigin)
                     .parser_metadata(ParserMetadata::NotParserInserted)
                     .use_url_credentials(true)
                     .pipeline_id(Some(pipeline_id))
-                    .referrer(referrer)
                     .referrer_policy(referrer_policy)
                     .origin(origin);
 
diff --git a/components/script/dom/eventsource.rs b/components/script/dom/eventsource.rs
index 4ab9d11f906..49e612cd6eb 100644
--- a/components/script/dom/eventsource.rs
+++ b/components/script/dom/eventsource.rs
@@ -532,6 +532,7 @@ impl EventSource {
             Destination::None,
             Some(cors_attribute_state),
             Some(true),
+            global.get_referrer(),
         )
         .origin(global.origin().immutable().clone())
         .pipeline_id(Some(global.pipeline_id()));
diff --git a/components/script/dom/globalscope.rs b/components/script/dom/globalscope.rs
index 987ae4e7c13..f84c0caa4ec 100644
--- a/components/script/dom/globalscope.rs
+++ b/components/script/dom/globalscope.rs
@@ -94,6 +94,7 @@ use net_traits::filemanager_thread::{
     FileManagerResult, FileManagerThreadMsg, ReadFileProgress, RelativePos,
 };
 use net_traits::image_cache::ImageCache;
+use net_traits::request::Referrer;
 use net_traits::response::HttpsState;
 use net_traits::{CoreResourceMsg, CoreResourceThread, IpcSend, ResourceThreads};
 use parking_lot::Mutex;
@@ -105,7 +106,7 @@ use script_traits::{
     ScriptToConstellationChan, TimerEvent,
 };
 use script_traits::{TimerEventId, TimerSchedulerMsg, TimerSource};
-use servo_url::{MutableOrigin, ServoUrl};
+use servo_url::{ImmutableOrigin, MutableOrigin, ServoUrl};
 use std::borrow::Cow;
 use std::cell::Cell;
 use std::collections::hash_map::Entry;
@@ -2331,6 +2332,43 @@ impl GlobalScope {
         unreachable!();
     }
 
+    /// Determine the Referrer for a request whose Referrer is "client"
+    pub fn get_referrer(&self) -> Referrer {
+        // Step 3 of https://w3c.github.io/webappsec-referrer-policy/#determine-requests-referrer
+        if let Some(window) = self.downcast::<Window>() {
+            // Substep 3.1
+
+            // Substep 3.1.1
+            let mut document = window.Document();
+
+            // Substep 3.1.2
+            if let ImmutableOrigin::Opaque(_) = document.origin().immutable() {
+                return Referrer::NoReferrer;
+            }
+
+            let mut url = document.url();
+
+            // Substep 3.1.3
+            while url.as_str() == "about:srcdoc" {
+                document = document
+                    .browsing_context()
+                    .expect("iframe should have browsing context")
+                    .parent()
+                    .expect("iframes browsing_context should have parent")
+                    .document()
+                    .expect("iframes parent should have document");
+
+                url = document.url();
+            }
+
+            // Substep 3.1.4
+            return Referrer::Client(url);
+        } else {
+            // Substep 3.2
+            return Referrer::ReferrerUrl(self.get_url());
+        }
+    }
+
     /// Extract a `Window`, panic if the global object is not a `Window`.
     pub fn as_window(&self) -> &Window {
         self.downcast::<Window>().expect("expected a Window scope")
diff --git a/components/script/dom/htmlanchorelement.rs b/components/script/dom/htmlanchorelement.rs
index f61d466afd5..42589dfce36 100644
--- a/components/script/dom/htmlanchorelement.rs
+++ b/components/script/dom/htmlanchorelement.rs
@@ -650,7 +650,7 @@ pub fn follow_hyperlink(subject: &Element, hyperlink_suffix: Option<String>) {
             Some(ref link_types) if link_types.Value().contains("noreferrer") => {
                 Referrer::NoReferrer
             },
-            _ => Referrer::Client,
+            _ => target_window.upcast::<GlobalScope>().get_referrer(),
         };
 
         // Step 14
@@ -659,7 +659,7 @@ pub fn follow_hyperlink(subject: &Element, hyperlink_suffix: Option<String>) {
             LoadOrigin::Script(document.origin().immutable().clone()),
             url,
             Some(pipeline_id),
-            Some(referrer),
+            referrer,
             referrer_policy,
         );
         let target = Trusted::new(target_window);
diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index 0c7b09ece74..b9b475e02ff 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -688,7 +688,7 @@ impl HTMLFormElement {
             LoadOrigin::Script(doc.origin().immutable().clone()),
             action_components,
             None,
-            Some(Referrer::ReferrerUrl(target_document.url())),
+            Referrer::ReferrerUrl(target_document.url()),
             target_document.get_referrer_policy(),
         );
 
@@ -840,13 +840,13 @@ impl HTMLFormElement {
             Some(ref link_types) if link_types.Value().contains("noreferrer") => {
                 Referrer::NoReferrer
             },
-            _ => Referrer::Client,
+            _ => target.upcast::<GlobalScope>().get_referrer(),
         };
 
         let referrer_policy = target.Document().get_referrer_policy();
         let pipeline_id = target.upcast::<GlobalScope>().pipeline_id();
         load_data.creator_pipeline_id = Some(pipeline_id);
-        load_data.referrer = Some(referrer);
+        load_data.referrer = referrer;
         load_data.referrer_policy = referrer_policy;
 
         // Step 4.
diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index b36d3641764..2e8a37a88d8 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -30,7 +30,6 @@ use dom_struct::dom_struct;
 use html5ever::{LocalName, Prefix};
 use ipc_channel::ipc;
 use msg::constellation_msg::{BrowsingContextId, PipelineId, TopLevelBrowsingContextId};
-use net_traits::request::Referrer;
 use profile_traits::ipc as ProfiledIpc;
 use script_layout_interface::message::ReflowGoal;
 use script_traits::IFrameSandboxState::{IFrameSandboxed, IFrameUnsandboxed};
@@ -242,7 +241,7 @@ impl HTMLIFrameElement {
                 LoadOrigin::Script(document.origin().immutable().clone()),
                 url,
                 pipeline_id,
-                Some(Referrer::ReferrerUrl(document.url())),
+                window.upcast::<GlobalScope>().get_referrer(),
                 document.get_referrer_policy(),
             );
             let element = self.upcast::<Element>();
@@ -325,7 +324,7 @@ impl HTMLIFrameElement {
             LoadOrigin::Script(document.origin().immutable().clone()),
             url,
             creator_pipeline_id,
-            Some(Referrer::ReferrerUrl(document.url())),
+            window.upcast::<GlobalScope>().get_referrer(),
             document.get_referrer_policy(),
         );
 
@@ -352,7 +351,7 @@ impl HTMLIFrameElement {
             LoadOrigin::Script(document.origin().immutable().clone()),
             url,
             pipeline_id,
-            Some(Referrer::ReferrerUrl(document.url().clone())),
+            window.upcast::<GlobalScope>().get_referrer(),
             document.get_referrer_policy(),
         );
         let browsing_context_id = BrowsingContextId::new();
diff --git a/components/script/dom/htmlimageelement.rs b/components/script/dom/htmlimageelement.rs
index 2e99e491653..893080edd07 100644
--- a/components/script/dom/htmlimageelement.rs
+++ b/components/script/dom/htmlimageelement.rs
@@ -63,7 +63,7 @@ use net_traits::image_cache::{
     CorsStatus, ImageCache, ImageCacheResult, ImageOrMetadataAvailable, ImageResponse,
     PendingImageId, PendingImageResponse, UsePlaceholder,
 };
-use net_traits::request::{CorsSettings, Destination, Initiator, RequestBuilder};
+use net_traits::request::{CorsSettings, Destination, Initiator, Referrer, RequestBuilder};
 use net_traits::{FetchMetadata, FetchResponseListener, FetchResponseMsg, NetworkError};
 use net_traits::{ReferrerPolicy, ResourceFetchTiming, ResourceTimingType};
 use num_traits::ToPrimitive;
@@ -297,13 +297,14 @@ pub(crate) enum FromPictureOrSrcSet {
 pub(crate) fn image_fetch_request(
     img_url: ServoUrl,
     origin: ImmutableOrigin,
+    referrer: Referrer,
     pipeline_id: PipelineId,
     cors_setting: Option<CorsSettings>,
     referrer_policy: Option<ReferrerPolicy>,
     from_picture_or_srcset: FromPictureOrSrcSet,
 ) -> RequestBuilder {
     let mut request =
-        create_a_potential_cors_request(img_url, Destination::Image, cors_setting, None)
+        create_a_potential_cors_request(img_url, Destination::Image, cors_setting, None, referrer)
             .origin(origin)
             .pipeline_id(Some(pipeline_id))
             .referrer_policy(referrer_policy);
@@ -383,6 +384,7 @@ impl HTMLImageElement {
         let request = image_fetch_request(
             img_url.clone(),
             document.origin().immutable().clone(),
+            document.global().get_referrer(),
             document.global().pipeline_id(),
             cors_setting_for_element(self.upcast()),
             referrer_policy_for_element(self.upcast()),
diff --git a/components/script/dom/htmlmediaelement.rs b/components/script/dom/htmlmediaelement.rs
index 3a5e9880375..27af41c2b0e 100644
--- a/components/script/dom/htmlmediaelement.rs
+++ b/components/script/dom/htmlmediaelement.rs
@@ -77,7 +77,7 @@ use ipc_channel::router::ROUTER;
 use media::{glplayer_channel, GLPlayerMsg, GLPlayerMsgForward, WindowGLContext};
 use net_traits::image::base::Image;
 use net_traits::image_cache::ImageResponse;
-use net_traits::request::{Destination, Referrer};
+use net_traits::request::Destination;
 use net_traits::{CoreResourceMsg, FetchChannels, FetchMetadata, FetchResponseListener, Metadata};
 use net_traits::{NetworkError, ResourceFetchTiming, ResourceTimingType};
 use script_layout_interface::HTMLMediaData;
@@ -846,12 +846,17 @@ impl HTMLMediaElement {
         };
 
         let cors_setting = cors_setting_for_element(self.upcast());
-        let request = create_a_potential_cors_request(url.clone(), destination, cors_setting, None)
-            .headers(headers)
-            .origin(document.origin().immutable().clone())
-            .pipeline_id(Some(self.global().pipeline_id()))
-            .referrer(Some(Referrer::ReferrerUrl(document.url())))
-            .referrer_policy(document.get_referrer_policy());
+        let request = create_a_potential_cors_request(
+            url.clone(),
+            destination,
+            cors_setting,
+            None,
+            self.global().get_referrer(),
+        )
+        .headers(headers)
+        .origin(document.origin().immutable().clone())
+        .pipeline_id(Some(self.global().pipeline_id()))
+        .referrer_policy(document.get_referrer_policy());
 
         let mut current_fetch_context = self.current_fetch_context.borrow_mut();
         if let Some(ref mut current_fetch_context) = *current_fetch_context {
diff --git a/components/script/dom/htmlscriptelement.rs b/components/script/dom/htmlscriptelement.rs
index bf3de043ff5..9b9bbb619f7 100644
--- a/components/script/dom/htmlscriptelement.rs
+++ b/components/script/dom/htmlscriptelement.rs
@@ -324,10 +324,9 @@ pub(crate) fn script_fetch_request(
     referrer_policy: Option<ReferrerPolicy>,
     integrity_metadata: String,
 ) -> RequestBuilder {
-    create_a_potential_cors_request(url, Destination::Script, cors_setting, None)
+    create_a_potential_cors_request(url, Destination::Script, cors_setting, None, referrer)
         .origin(origin)
         .pipeline_id(Some(pipeline_id))
-        .referrer(Some(referrer))
         .referrer_policy(referrer_policy)
         .integrity_metadata(integrity_metadata)
 }
diff --git a/components/script/dom/htmlvideoelement.rs b/components/script/dom/htmlvideoelement.rs
index cea37bc173c..2100b70330d 100644
--- a/components/script/dom/htmlvideoelement.rs
+++ b/components/script/dom/htmlvideoelement.rs
@@ -189,7 +189,7 @@ impl HTMLVideoElement {
     ) {
         // Continuation of step 4.
         let document = document_from_node(self);
-        let request = RequestBuilder::new(poster_url.clone())
+        let request = RequestBuilder::new(poster_url.clone(), document.global().get_referrer())
             .destination(Destination::Image)
             .credentials_mode(CredentialsMode::Include)
             .use_url_credentials(true)
diff --git a/components/script/dom/location.rs b/components/script/dom/location.rs
index 5882a024912..48e8ea0c744 100644
--- a/components/script/dom/location.rs
+++ b/components/script/dom/location.rs
@@ -50,7 +50,7 @@ impl Location {
             LoadOrigin::Script(document.origin().immutable().clone()),
             url,
             Some(pipeline_id),
-            Some(referrer),
+            referrer,
             referrer_policy,
         );
         // TODO: rethrow exceptions, set exceptions enabled flag.
diff --git a/components/script/dom/request.rs b/components/script/dom/request.rs
index 89d9d54506a..27d2a1e61bc 100644
--- a/components/script/dom/request.rs
+++ b/components/script/dom/request.rs
@@ -180,7 +180,7 @@ impl Request {
             // Step 14.2 TODO: "Unset request's reload-navigation flag."
             // Step 14.3 TODO: "Unset request's history-navigation flag."
             // Step 14.4
-            request.referrer = NetTraitsRequestReferrer::Client;
+            request.referrer = global.get_referrer();
             // Step 14.5
             request.referrer_policy = None;
         }
@@ -206,7 +206,7 @@ impl Request {
                         parsed_referrer.path() == "client") ||
                         parsed_referrer.origin() != origin
                     {
-                        request.referrer = NetTraitsRequestReferrer::Client;
+                        request.referrer = global.get_referrer();
                     } else {
                         // Step 15.3.4
                         request.referrer = NetTraitsRequestReferrer::ReferrerUrl(parsed_referrer);
@@ -486,7 +486,8 @@ fn net_request_from_global(global: &GlobalScope, url: ServoUrl) -> NetTraitsRequ
     let origin = Origin::Origin(global.get_url().origin());
     let https_state = global.get_https_state();
     let pipeline_id = global.pipeline_id();
-    NetTraitsRequest::new(url, Some(origin), Some(pipeline_id), https_state)
+    let referrer = NetTraitsRequestReferrer::ReferrerUrl(global.get_url());
+    NetTraitsRequest::new(url, Some(origin), referrer, Some(pipeline_id), https_state)
 }
 
 // https://fetch.spec.whatwg.org/#concept-method-normalize
@@ -567,7 +568,7 @@ impl RequestMethods for Request {
         let r = self.request.borrow();
         USVString(match r.referrer {
             NetTraitsRequestReferrer::NoReferrer => String::from(""),
-            NetTraitsRequestReferrer::Client => String::from("about:client"),
+            NetTraitsRequestReferrer::Client(_) => String::from("about:client"),
             NetTraitsRequestReferrer::ReferrerUrl(ref u) => {
                 let u_c = u.clone();
                 u_c.into_string()
diff --git a/components/script/dom/serviceworkerglobalscope.rs b/components/script/dom/serviceworkerglobalscope.rs
index 840ee81f764..4bea29cda50 100644
--- a/components/script/dom/serviceworkerglobalscope.rs
+++ b/components/script/dom/serviceworkerglobalscope.rs
@@ -309,18 +309,6 @@ impl ServiceWorkerGlobalScope {
                     pipeline_id,
                 } = worker_load_origin;
 
-                let referrer = referrer_url.map(|referrer_url| Referrer::ReferrerUrl(referrer_url));
-
-                let request = RequestBuilder::new(script_url.clone())
-                    .destination(Destination::ServiceWorker)
-                    .credentials_mode(CredentialsMode::Include)
-                    .parser_metadata(ParserMetadata::NotParserInserted)
-                    .use_url_credentials(true)
-                    .pipeline_id(Some(pipeline_id))
-                    .referrer(referrer)
-                    .referrer_policy(referrer_policy)
-                    .origin(origin);
-
                 // Service workers are time limited
                 // https://w3c.github.io/ServiceWorker/#service-worker-lifetime
                 let sw_lifetime_timeout = pref!(dom.serviceworker.timeout_seconds) as u64;
@@ -333,7 +321,7 @@ impl ServiceWorkerGlobalScope {
                 let resource_threads_sender = init.resource_threads.sender();
                 let global = ServiceWorkerGlobalScope::new(
                     init,
-                    script_url,
+                    script_url.clone(),
                     devtools_mpsc_port,
                     runtime,
                     own_sender,
@@ -344,6 +332,19 @@ impl ServiceWorkerGlobalScope {
                     control_receiver,
                 );
 
+                let referrer = referrer_url
+                    .map(|url| Referrer::ReferrerUrl(url))
+                    .unwrap_or_else(|| global.upcast::<GlobalScope>().get_referrer());
+
+                let request = RequestBuilder::new(script_url, referrer)
+                    .destination(Destination::ServiceWorker)
+                    .credentials_mode(CredentialsMode::Include)
+                    .parser_metadata(ParserMetadata::NotParserInserted)
+                    .use_url_credentials(true)
+                    .pipeline_id(Some(pipeline_id))
+                    .referrer_policy(referrer_policy)
+                    .origin(origin);
+
                 let (_url, source) =
                     match load_whole_resource(request, &resource_threads_sender, &*global.upcast())
                     {
diff --git a/components/script/dom/servoparser/prefetch.rs b/components/script/dom/servoparser/prefetch.rs
index c7468be7c19..e5ae112620f 100644
--- a/components/script/dom/servoparser/prefetch.rs
+++ b/components/script/dom/servoparser/prefetch.rs
@@ -126,6 +126,7 @@ impl TokenSink for PrefetchSink {
                     let request = image_fetch_request(
                         url,
                         self.origin.clone(),
+                        self.referrer.clone(),
                         self.pipeline_id,
                         self.get_cors_settings(tag, local_name!("crossorigin")),
                         self.get_referrer_policy(tag, local_name!("referrerpolicy")),
diff --git a/components/script/dom/websocket.rs b/components/script/dom/websocket.rs
index 89aeda77ebd..83d1cf1069d 100644
--- a/components/script/dom/websocket.rs
+++ b/components/script/dom/websocket.rs
@@ -198,10 +198,9 @@ impl WebSocket {
         let address = Trusted::new(&*ws);
 
         // Step 8.
-        let request = RequestBuilder::new(url_record)
+        let request = RequestBuilder::new(url_record, Referrer::NoReferrer)
             .origin(global.origin().immutable().clone())
-            .mode(RequestMode::WebSocket { protocols })
-            .referrer(Some(Referrer::NoReferrer));
+            .mode(RequestMode::WebSocket { protocols });
 
         let channels = FetchChannels::WebSocket {
             event_sender: resource_event_sender,
diff --git a/components/script/dom/windowproxy.rs b/components/script/dom/windowproxy.rs
index 9aac99dc447..8be356e5ea2 100644
--- a/components/script/dom/windowproxy.rs
+++ b/components/script/dom/windowproxy.rs
@@ -305,7 +305,7 @@ impl WindowProxy {
                 LoadOrigin::Script(document.origin().immutable().clone()),
                 blank_url,
                 None,
-                Some(Referrer::ReferrerUrl(document.url().clone())),
+                document.global().get_referrer(),
                 document.get_referrer_policy(),
             );
             let load_info = AuxiliaryBrowsingContextLoadInfo {
@@ -506,7 +506,7 @@ impl WindowProxy {
             let referrer = if noreferrer {
                 Referrer::NoReferrer
             } else {
-                Referrer::Client
+                target_window.upcast::<GlobalScope>().get_referrer()
             };
             // Step 14.5
             let referrer_policy = target_document.get_referrer_policy();
@@ -515,7 +515,7 @@ impl WindowProxy {
                 LoadOrigin::Script(existing_document.origin().immutable().clone()),
                 url,
                 Some(pipeline_id),
-                Some(referrer),
+                referrer,
                 referrer_policy,
             );
             let replacement_flag = if new {
diff --git a/components/script/dom/workerglobalscope.rs b/components/script/dom/workerglobalscope.rs
index 9cb99b7d154..3ff31542b56 100644
--- a/components/script/dom/workerglobalscope.rs
+++ b/components/script/dom/workerglobalscope.rs
@@ -252,7 +252,7 @@ impl WorkerGlobalScopeMethods for WorkerGlobalScope {
         rooted!(in(self.runtime.borrow().as_ref().unwrap().cx()) let mut rval = UndefinedValue());
         for url in urls {
             let global_scope = self.upcast::<GlobalScope>();
-            let request = NetRequestInit::new(url.clone())
+            let request = NetRequestInit::new(url.clone(), global_scope.get_referrer())
                 .destination(Destination::Script)
                 .credentials_mode(CredentialsMode::Include)
                 .parser_metadata(ParserMetadata::NotParserInserted)
diff --git a/components/script/dom/worklet.rs b/components/script/dom/worklet.rs
index 3e92e09257d..46930bbf651 100644
--- a/components/script/dom/worklet.rs
+++ b/components/script/dom/worklet.rs
@@ -624,11 +624,14 @@ impl WorkletThread {
         // TODO: Fetch the script asynchronously?
         // TODO: Caching.
         let resource_fetcher = self.global_init.resource_threads.sender();
-        let request = RequestBuilder::new(script_url)
-            .destination(Destination::Script)
-            .mode(RequestMode::CorsMode)
-            .credentials_mode(credentials.into())
-            .origin(origin);
+        let request = RequestBuilder::new(
+            script_url,
+            global_scope.upcast::<GlobalScope>().get_referrer(),
+        )
+        .destination(Destination::Script)
+        .mode(RequestMode::CorsMode)
+        .credentials_mode(credentials.into())
+        .origin(origin);
 
         let script = load_whole_resource(
             request,
diff --git a/components/script/dom/xmlhttprequest.rs b/components/script/dom/xmlhttprequest.rs
index 03a5f5c7bff..2e8a37ea240 100644
--- a/components/script/dom/xmlhttprequest.rs
+++ b/components/script/dom/xmlhttprequest.rs
@@ -679,28 +679,29 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
             None => None,
         };
 
-        let mut request = RequestBuilder::new(self.request_url.borrow().clone().unwrap())
-            .method(self.request_method.borrow().clone())
-            .headers((*self.request_headers.borrow()).clone())
-            .unsafe_request(true)
-            // XXXManishearth figure out how to avoid this clone
-            .body(extracted_or_serialized.map(|e| e.into_net_request_body().0))
-            // XXXManishearth actually "subresource", but it doesn't exist
-            // https://github.com/whatwg/xhr/issues/71
-            .destination(Destination::None)
-            .synchronous(self.sync.get())
-            .mode(RequestMode::CorsMode)
-            .use_cors_preflight(has_handlers)
-            .credentials_mode(credentials_mode)
-            .use_url_credentials(use_url_credentials)
-            .origin(self.global().origin().immutable().clone())
-            .referrer(
-                self.referrer_url
-                    .clone()
-                    .map(|referrer_url| Referrer::ReferrerUrl(referrer_url)),
-            )
-            .referrer_policy(self.referrer_policy.clone())
-            .pipeline_id(Some(self.global().pipeline_id()));
+        let mut request = RequestBuilder::new(
+            self.request_url.borrow().clone().unwrap(),
+            self.referrer_url
+                .clone()
+                .map(|url| Referrer::ReferrerUrl(url))
+                .unwrap_or_else(|| self.global().get_referrer()),
+        )
+        .method(self.request_method.borrow().clone())
+        .headers((*self.request_headers.borrow()).clone())
+        .unsafe_request(true)
+        // XXXManishearth figure out how to avoid this clone
+        .body(extracted_or_serialized.map(|e| e.into_net_request_body().0))
+        // XXXManishearth actually "subresource", but it doesn't exist
+        // https://github.com/whatwg/xhr/issues/71
+        .destination(Destination::None)
+        .synchronous(self.sync.get())
+        .mode(RequestMode::CorsMode)
+        .use_cors_preflight(has_handlers)
+        .credentials_mode(credentials_mode)
+        .use_url_credentials(use_url_credentials)
+        .origin(self.global().origin().immutable().clone())
+        .referrer_policy(self.referrer_policy.clone())
+        .pipeline_id(Some(self.global().pipeline_id()));
 
         // step 4 (second half)
         match content_type {
diff --git a/components/script/fetch.rs b/components/script/fetch.rs
index e26370016e6..9aaeb204245 100644
--- a/components/script/fetch.rs
+++ b/components/script/fetch.rs
@@ -29,7 +29,7 @@ use ipc_channel::router::ROUTER;
 use net_traits::request::{
     CorsSettings, CredentialsMode, Destination, RequestBuilder, RequestMode,
 };
-use net_traits::request::{Request as NetTraitsRequest, ServiceWorkersMode};
+use net_traits::request::{Referrer, Request as NetTraitsRequest, ServiceWorkersMode};
 use net_traits::CoreResourceMsg::Fetch as NetTraitsFetch;
 use net_traits::{CoreResourceMsg, CoreResourceThread, FetchResponseMsg};
 use net_traits::{FetchChannels, FetchResponseListener, NetworkError};
@@ -117,7 +117,7 @@ fn request_init_from_request(request: NetTraitsRequest) -> RequestBuilder {
             .origin()
             .immutable()
             .clone(),
-        referrer: Some(request.referrer.clone()),
+        referrer: request.referrer.clone(),
         referrer_policy: request.referrer_policy,
         pipeline_id: request.pipeline_id,
         redirect_mode: request.redirect_mode,
@@ -357,8 +357,9 @@ pub(crate) fn create_a_potential_cors_request(
     destination: Destination,
     cors_setting: Option<CorsSettings>,
     same_origin_fallback: Option<bool>,
+    referrer: Referrer,
 ) -> RequestBuilder {
-    RequestBuilder::new(url)
+    RequestBuilder::new(url, referrer)
         // https://html.spec.whatwg.org/multipage/#create-a-potential-cors-request
         // Step 1
         .mode(match cors_setting {
diff --git a/components/script/layout_image.rs b/components/script/layout_image.rs
index 242fa688c51..68ece467ad7 100644
--- a/components/script/layout_image.rs
+++ b/components/script/layout_image.rs
@@ -110,7 +110,7 @@ pub fn fetch_image_for_layout(
         }),
     );
 
-    let request = FetchRequestInit::new(url)
+    let request = FetchRequestInit::new(url, document.global().get_referrer())
         .origin(document.origin().immutable().clone())
         .destination(Destination::Image)
         .pipeline_id(Some(document.global().pipeline_id()));
diff --git a/components/script/script_module.rs b/components/script/script_module.rs
index 0ffe66d540e..0a890623e62 100644
--- a/components/script/script_module.rs
+++ b/components/script/script_module.rs
@@ -720,6 +720,8 @@ impl ModuleTree {
                 }
 
                 // Step 8.
+
+                let referrer = global.get_referrer();
                 for url in urls {
                     // https://html.spec.whatwg.org/multipage/#internal-module-script-graph-fetching-procedure
                     // Step 1.
@@ -731,7 +733,7 @@ impl ModuleTree {
                         url.clone(),
                         visited_urls.clone(),
                         destination.clone(),
-                        Referrer::Client,
+                        referrer.clone(),
                         ParserMetadata::NotParserInserted,
                         "".to_owned(), // integrity
                         credentials_mode.clone(),
@@ -1225,6 +1227,7 @@ pub fn fetch_external_module_script(
 ) {
     let mut visited_urls = HashSet::new();
     visited_urls.insert(url.clone());
+    let referrer = owner.global().get_referrer();
 
     // Step 1.
     fetch_single_module_script(
@@ -1232,7 +1235,7 @@ pub fn fetch_external_module_script(
         url,
         visited_urls,
         destination,
-        Referrer::Client,
+        referrer,
         ParserMetadata::NotParserInserted,
         integrity_metadata,
         credentials_mode,
@@ -1322,10 +1325,9 @@ pub fn fetch_single_module_script(
     };
 
     // Step 7-8.
-    let request = RequestBuilder::new(url.clone())
+    let request = RequestBuilder::new(url.clone(), referrer)
         .destination(destination.clone())
         .origin(global.origin().immutable().clone())
-        .referrer(Some(referrer))
         .parser_metadata(parser_metadata)
         .integrity_metadata(integrity_metadata.clone())
         .credentials_mode(credentials_mode)
diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index 61f597468f8..16f414656e5 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -3669,13 +3669,12 @@ impl ScriptThread {
     /// argument until a notification is received that the fetch is complete.
     fn pre_page_load(&self, mut incomplete: InProgressLoad, load_data: LoadData) {
         let id = incomplete.pipeline_id.clone();
-        let req_init = RequestBuilder::new(load_data.url.clone())
+        let req_init = RequestBuilder::new(load_data.url.clone(), load_data.referrer)
             .method(load_data.method)
             .destination(Destination::Document)
             .credentials_mode(CredentialsMode::Include)
             .use_url_credentials(true)
             .pipeline_id(Some(id))
-            .referrer(load_data.referrer)
             .referrer_policy(load_data.referrer_policy)
             .headers(load_data.headers)
             .body(load_data.data)
diff --git a/components/script/stylesheet_loader.rs b/components/script/stylesheet_loader.rs
index b0c52d5fc8c..9db09deb2b0 100644
--- a/components/script/stylesheet_loader.rs
+++ b/components/script/stylesheet_loader.rs
@@ -344,10 +344,9 @@ pub(crate) fn stylesheet_fetch_request(
     referrer_policy: Option<ReferrerPolicy>,
     integrity_metadata: String,
 ) -> RequestBuilder {
-    create_a_potential_cors_request(url, Destination::Style, cors_setting, None)
+    create_a_potential_cors_request(url, Destination::Style, cors_setting, None, referrer)
         .origin(origin)
         .pipeline_id(Some(pipeline_id))
-        .referrer(Some(referrer))
         .referrer_policy(referrer_policy)
         .integrity_metadata(integrity_metadata)
 }
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index b3e92cbce21..d50f34ed554 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -176,7 +176,7 @@ pub struct LoadData {
     /// The result of evaluating a javascript scheme url.
     pub js_eval_result: Option<JsEvalResult>,
     /// The referrer.
-    pub referrer: Option<Referrer>,
+    pub referrer: Referrer,
     /// The referrer policy.
     pub referrer_policy: Option<ReferrerPolicy>,
 
@@ -200,7 +200,7 @@ impl LoadData {
         load_origin: LoadOrigin,
         url: ServoUrl,
         creator_pipeline_id: Option<PipelineId>,
-        referrer: Option<Referrer>,
+        referrer: Referrer,
         referrer_policy: Option<ReferrerPolicy>,
     ) -> LoadData {
         LoadData {
diff --git a/components/webdriver_server/Cargo.toml b/components/webdriver_server/Cargo.toml
index 2e8ffbb4708..146f825c89d 100644
--- a/components/webdriver_server/Cargo.toml
+++ b/components/webdriver_server/Cargo.toml
@@ -22,6 +22,7 @@ ipc-channel = "0.14"
 keyboard-types = "0.4.3"
 log = "0.4"
 msg = { path = "../msg" }
+net_traits = { path = "../net_traits" }
 pixels = { path = "../pixels" }
 script_traits = { path = "../script_traits" }
 serde = "1"
diff --git a/components/webdriver_server/lib.rs b/components/webdriver_server/lib.rs
index 50fe8d8c867..3b53127d0d9 100644
--- a/components/webdriver_server/lib.rs
+++ b/components/webdriver_server/lib.rs
@@ -28,6 +28,7 @@ use ipc_channel::ipc::{self, IpcSender};
 use ipc_channel::router::ROUTER;
 use keyboard_types::webdriver::send_keys;
 use msg::constellation_msg::{BrowsingContextId, TopLevelBrowsingContextId, TraversalDirection};
+use net_traits::request::Referrer;
 use pixels::PixelFormat;
 use script_traits::webdriver_msg::{LoadStatus, WebDriverCookieError, WebDriverFrameId};
 use script_traits::webdriver_msg::{
@@ -643,7 +644,7 @@ impl Handler {
 
         let top_level_browsing_context_id = self.session()?.top_level_browsing_context_id;
 
-        let load_data = LoadData::new(LoadOrigin::WebDriver, url, None, None, None);
+        let load_data = LoadData::new(LoadOrigin::WebDriver, url, None, Referrer::NoReferrer, None);
         let cmd_msg = WebDriverCommandMsg::LoadUrl(
             top_level_browsing_context_id,
             load_data,