diff --git a/docshell/base/nsDocShell.cpp b/docshell/base/nsDocShell.cpp
index 46f0f5017dc..0e4550100d8 100644
--- a/docshell/base/nsDocShell.cpp
+++ b/docshell/base/nsDocShell.cpp
@@ -5203,6 +5203,7 @@ nsDocShell::DisplayLoadError(nsresult aError, nsIURI* aURI,
       case NS_ERROR_BAD_OPAQUE_INTERCEPTION_REQUEST_MODE:
       case NS_ERROR_INTERCEPTED_ERROR_RESPONSE:
       case NS_ERROR_INTERCEPTED_USED_RESPONSE:
+      case NS_ERROR_CLIENT_REQUEST_OPAQUE_INTERCEPTION:
         // ServiceWorker intercepted request, but something went wrong.
         nsContentUtils::MaybeReportInterceptionErrorToConsole(GetDocument(),
                                                               aError);
@@ -7840,6 +7841,7 @@ nsDocShell::EndPageLoad(nsIWebProgress* aProgress,
                aStatus == NS_ERROR_BAD_OPAQUE_INTERCEPTION_REQUEST_MODE ||
                aStatus == NS_ERROR_INTERCEPTED_ERROR_RESPONSE ||
                aStatus == NS_ERROR_INTERCEPTED_USED_RESPONSE ||
+               aStatus == NS_ERROR_CLIENT_REQUEST_OPAQUE_INTERCEPTION ||
                NS_ERROR_GET_MODULE(aStatus) == NS_ERROR_MODULE_SECURITY) {
       // Errors to be shown for any frame
       DisplayLoadError(aStatus, url, nullptr, aChannel);
diff --git a/dom/base/nsContentUtils.cpp b/dom/base/nsContentUtils.cpp
index 8076f8d98c7..5abc257bb38 100644
--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -3432,6 +3432,8 @@ nsContentUtils::MaybeReportInterceptionErrorToConsole(nsIDocument* aDocument,
     messageName = "InterceptedErrorResponse";
   } else if (aError == NS_ERROR_INTERCEPTED_USED_RESPONSE) {
     messageName = "InterceptedUsedResponse";
+  } else if (aError == NS_ERROR_CLIENT_REQUEST_OPAQUE_INTERCEPTION) {
+    messageName = "ClientRequestOpaqueInterception";
   }
 
   if (messageName) {
diff --git a/dom/fetch/InternalRequest.cpp b/dom/fetch/InternalRequest.cpp
index 448d5d4ff07..86b5c42e563 100644
--- a/dom/fetch/InternalRequest.cpp
+++ b/dom/fetch/InternalRequest.cpp
@@ -195,5 +195,44 @@ InternalRequest::MapContentPolicyTypeToRequestContext(nsContentPolicyType aConte
   return context;
 }
 
+bool
+InternalRequest::IsNavigationRequest() const
+{
+  // https://fetch.spec.whatwg.org/#navigation-request-context
+  //
+  // A navigation request context is one of "form", "frame", "hyperlink",
+  // "iframe", "internal" (as long as context frame type is not "none"),
+  // "location", "metarefresh", and "prerender".
+  //
+  // TODO: include equivalent check for "form" context
+  // TODO: include equivalent check for "prerender" context
+  return mContentPolicyType == nsIContentPolicy::TYPE_DOCUMENT ||
+         mContentPolicyType == nsIContentPolicy::TYPE_SUBDOCUMENT ||
+         mContentPolicyType == nsIContentPolicy::TYPE_INTERNAL_FRAME ||
+         mContentPolicyType == nsIContentPolicy::TYPE_INTERNAL_IFRAME ||
+         mContentPolicyType == nsIContentPolicy::TYPE_REFRESH;
+}
+
+bool
+InternalRequest::IsWorkerRequest() const
+{
+  // https://fetch.spec.whatwg.org/#worker-request-context
+  //
+  // A worker request context is one of "serviceworker", "sharedworker", and
+  // "worker".
+  //
+  // Note, service workers are not included here because currently there is
+  // no way to generate a Request with a "serviceworker" RequestContext.
+  // ServiceWorker scripts cannot be intercepted.
+  return mContentPolicyType == nsIContentPolicy::TYPE_INTERNAL_WORKER ||
+         mContentPolicyType == nsIContentPolicy::TYPE_INTERNAL_SHARED_WORKER;
+}
+
+bool
+InternalRequest::IsClientRequest() const
+{
+  return IsNavigationRequest() || IsWorkerRequest();
+}
+
 } // namespace dom
 } // namespace mozilla
diff --git a/dom/fetch/InternalRequest.h b/dom/fetch/InternalRequest.h
index 92b6cc3bab1..d20ac226f00 100644
--- a/dom/fetch/InternalRequest.h
+++ b/dom/fetch/InternalRequest.h
@@ -356,6 +356,16 @@ public:
     mCreatedByFetchEvent = false;
   }
 
+  bool
+  IsNavigationRequest() const;
+
+  bool
+  IsWorkerRequest() const;
+
+  bool
+  IsClientRequest() const;
+
+
 private:
   // Does not copy mBodyStream.  Use fallible Clone() for complete copy.
   explicit InternalRequest(const InternalRequest& aOther);
diff --git a/dom/locales/en-US/chrome/dom/dom.properties b/dom/locales/en-US/chrome/dom/dom.properties
index 3c4b63fb43d..c76539dbf82 100644
--- a/dom/locales/en-US/chrome/dom/dom.properties
+++ b/dom/locales/en-US/chrome/dom/dom.properties
@@ -176,3 +176,5 @@ BadOpaqueInterceptionRequestMode=A ServiceWorker passed an opaque Response to Fe
 InterceptedErrorResponse=A ServiceWorker passed an Error Response to FetchEvent.respondWith(). This typically means the ServiceWorker performed an invalid fetch() call.
 # LOCALIZATION NOTE: Do not translate "ServiceWorker", "Response", "FetchEvent.respondWith()", or "Response.clone()".
 InterceptedUsedResponse=A ServiceWorker passed a used Response to FetchEvent.respondWith(). The body of a Response may only be read once. Use Response.clone() to access the body multiple times.
+# LOCALIZATION NOTE: Do not translate "ServiceWorker", "Response", "FetchEvent.respondWith()", "FetchEvent.request", or "Worker".
+ClientRequestOpaqueInterception=A ServiceWorker passed an opaque Response to FetchEvent.respondWith() while FetchEvent.request was a client request. A client request is generally a browser navigation or top-level Worker script.
diff --git a/dom/workers/ServiceWorkerEvents.cpp b/dom/workers/ServiceWorkerEvents.cpp
index ce27b34ae9b..cb925d9c68a 100644
--- a/dom/workers/ServiceWorkerEvents.cpp
+++ b/dom/workers/ServiceWorkerEvents.cpp
@@ -149,15 +149,17 @@ class RespondWithHandler final : public PromiseNativeHandler
   nsMainThreadPtrHandle<nsIInterceptedChannel> mInterceptedChannel;
   nsMainThreadPtrHandle<ServiceWorker> mServiceWorker;
   RequestMode mRequestMode;
+  bool mIsClientRequest;
 public:
   NS_DECL_ISUPPORTS
 
   RespondWithHandler(nsMainThreadPtrHandle<nsIInterceptedChannel>& aChannel,
                      nsMainThreadPtrHandle<ServiceWorker>& aServiceWorker,
-                     RequestMode aRequestMode)
+                     RequestMode aRequestMode, bool aIsClientRequest)
     : mInterceptedChannel(aChannel)
     , mServiceWorker(aServiceWorker)
     , mRequestMode(aRequestMode)
+    , mIsClientRequest(aIsClientRequest)
   {
   }
 
@@ -262,15 +264,26 @@ RespondWithHandler::ResolvedCallback(JSContext* aCx, JS::Handle<JS::Value> aValu
     return;
   }
 
-  // Section 4.2, step 2.2 "If either response's type is "opaque" and request's
-  // mode is not "no-cors" or response's type is error, return a network error."
+  // Section 4.2, step 2.2:
+  //  If one of the following conditions is true, return a network error:
+  //    * response's type is "error".
+  //    * request's mode is not "no-cors" and response's type is "opaque".
+  //    * request is a client request and response's type is neither "basic"
+  //      nor "default".
+
+  if (response->Type() == ResponseType::Error) {
+    autoCancel.SetCancelStatus(NS_ERROR_INTERCEPTED_ERROR_RESPONSE);
+    return;
+  }
+
   if (response->Type() == ResponseType::Opaque && mRequestMode != RequestMode::No_cors) {
     autoCancel.SetCancelStatus(NS_ERROR_BAD_OPAQUE_INTERCEPTION_REQUEST_MODE);
     return;
   }
 
-  if (response->Type() == ResponseType::Error) {
-    autoCancel.SetCancelStatus(NS_ERROR_INTERCEPTED_ERROR_RESPONSE);
+  if (mIsClientRequest && response->Type() != ResponseType::Basic &&
+      response->Type() != ResponseType::Default) {
+    autoCancel.SetCancelStatus(NS_ERROR_CLIENT_REQUEST_OPAQUE_INTERCEPTION);
     return;
   }
 
@@ -357,9 +370,11 @@ FetchEvent::RespondWith(const ResponseOrPromise& aArg, ErrorResult& aRv)
   } else if (aArg.IsPromise()) {
     promise = &aArg.GetAsPromise();
   }
+  nsRefPtr<InternalRequest> ir = mRequest->GetInternalRequest();
   mWaitToRespond = true;
   nsRefPtr<RespondWithHandler> handler =
-    new RespondWithHandler(mChannel, mServiceWorker, mRequest->Mode());
+    new RespondWithHandler(mChannel, mServiceWorker, mRequest->Mode(),
+                           ir->IsClientRequest());
   promise->AppendNativeHandler(handler);
 }
 
diff --git a/dom/workers/test/serviceworkers/app-protocol/application.zip b/dom/workers/test/serviceworkers/app-protocol/application.zip
index f8669cd77e4..7d4be7f4617 100644
Binary files a/dom/workers/test/serviceworkers/app-protocol/application.zip and b/dom/workers/test/serviceworkers/app-protocol/application.zip differ
diff --git a/dom/workers/test/serviceworkers/app-protocol/controlled.html b/dom/workers/test/serviceworkers/app-protocol/controlled.html
index 27d16c19f9d..ce8ce987e0a 100644
--- a/dom/workers/test/serviceworkers/app-protocol/controlled.html
+++ b/dom/workers/test/serviceworkers/app-protocol/controlled.html
@@ -21,10 +21,12 @@ function runTests() {
         return testFetchAppResource('test_custom_content_type',
                                     'customContentType', 'text/html');
     })
-    .then(testRedirectedResponse)
-    .then(testRedirectedHttpsResponse)
-    .then(testCachedRedirectedResponse)
-    .then(testCachedRedirectedHttpsResponse)
+    // XXX: Cross-origin interceptions without CORS result in opaque responses
+    //      which are illegal for navigations like iframes. (bug 1183313)
+    //.then(testRedirectedResponse)
+    //.then(testRedirectedHttpsResponse)
+    //.then(testCachedRedirectedResponse)
+    //.then(testCachedRedirectedHttpsResponse)
     .then(done);
 }
   </script>
diff --git a/xpcom/base/ErrorList.h b/xpcom/base/ErrorList.h
index 13a42de1990..e05c9dd70b2 100644
--- a/xpcom/base/ErrorList.h
+++ b/xpcom/base/ErrorList.h
@@ -331,6 +331,8 @@
   ERROR(NS_ERROR_INTERCEPTED_ERROR_RESPONSE,           FAILURE(103)),
   /* Service worker intercepted with a response with bodyUsed set to true */
   ERROR(NS_ERROR_INTERCEPTED_USED_RESPONSE,            FAILURE(104)),
+  /* Service worker intercepted a client request with an opaque response */
+  ERROR(NS_ERROR_CLIENT_REQUEST_OPAQUE_INTERCEPTION,   FAILURE(105)),
 #undef MODULE