diff --git a/testing/web-platform/tests/service-workers/service-worker/navigation-headers.https.html b/testing/web-platform/tests/service-workers/service-worker/navigation-headers.https.html
new file mode 100644
index 000000000000..410b8e4631c1
--- /dev/null
+++ b/testing/web-platform/tests/service-workers/service-worker/navigation-headers.https.html
@@ -0,0 +1,558 @@
+<!DOCTYPE html>
+<meta charset="utf-8"/>
+<title>Service Worker: Navigation Post Request Origin Header</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/common/get-host-info.sub.js"></script>
+<script src="/service-workers/service-worker/resources/test-helpers.sub.js"></script>
+<body>
+<script>
+'use strict';
+
+const script = new URL('./resources/fetch-rewrite-worker.js', self.location);
+const base = './resources/navigation-headers-server.py';
+const scope = base + '?with-sw';
+let registration;
+
+async function post_and_get_headers(t, form_host, method, swaction) {
+  if (swaction === 'navpreload') {
+    assert_true('navigationPreload' in registration,
+                'navigation preload must be supported');
+  }
+  let target_string;
+  if (swaction === 'no-sw') {
+    target_string = base + '?no-sw';
+  } else if (swaction === 'fallback') {
+    target_string = `${scope}&ignore`;
+  } else {
+    target_string = `${scope}&${swaction}`;
+  }
+  const target = new URL(target_string, self.location);
+
+  let popup_url_path;
+  if (method === 'GET') {
+    popup_url_path = './resources/location-setter.html';
+  } else if (method === 'POST') {
+    popup_url_path = './resources/form-poster.html';
+  }
+
+  const popup_url = new URL(popup_url_path, self.location);
+  const tmp_params = new URLSearchParams();
+  tmp_params.set('target', encodeURIComponent(target));
+  popup_url.hostname = form_host;
+  popup_url.search = tmp_params.toString();
+
+  const message_promise = new Promise(resolve => {
+    self.addEventListener('message', evt => {
+      resolve(evt.data);
+    });
+  });
+
+  const frame = await with_iframe(popup_url);
+  t.add_cleanup(() => frame.remove());
+
+  return await message_promise;
+}
+
+const SAME_ORIGIN = new URL(self.location.origin);
+const SAME_SITE = new URL(get_host_info().HTTPS_REMOTE_ORIGIN);
+const CROSS_SITE = new URL(get_host_info().HTTPS_NOTSAMESITE_ORIGIN);
+
+promise_test(async t => {
+  registration = await service_worker_unregister_and_register(t, script, scope);
+  await wait_for_state(t, registration.installing, 'activated');
+  if (registration.navigationPreload)
+    await registration.navigationPreload.enable();
+}, 'Setup service worker');
+
+//
+// Origin and referer headers
+//
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'no-sw');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, SAME_ORIGIN.href, 'referer header');
+}, 'GET Navigation, same-origin with no service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'POST',
+                                            'no-sw');
+  assert_equals(result.origin, SAME_ORIGIN.origin, 'origin header');
+  assert_equals(result.referer, SAME_ORIGIN.href, 'referer header');
+}, 'POST Navigation, same-origin with no service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'passthrough');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, SAME_ORIGIN.href, 'referer header');
+}, 'GET Navigation, same-origin with passthrough service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'POST',
+                                            'passthrough');
+  assert_equals(result.origin, SAME_ORIGIN.origin, 'origin header');
+  assert_equals(result.referer, SAME_ORIGIN.href, 'referer header');
+}, 'POST Navigation, same-origin with passthrough service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'fallback');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, SAME_ORIGIN.href, 'referer header');
+}, 'GET Navigation, same-origin with fallback service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'POST',
+                                            'fallback');
+  assert_equals(result.origin, SAME_ORIGIN.origin, 'origin header');
+  assert_equals(result.referer, SAME_ORIGIN.href, 'referer header');
+}, 'POST Navigation, same-origin with fallback service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'navpreload');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, SAME_ORIGIN.href, 'referer header');
+}, 'GET Navigation, same-origin with navpreload service worker sets correct ' +
+   'origin and referer headers.');
+
+// There is no POST test for navpreload since the feature only supports GET
+// requests.
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'change-request');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, script.href, 'referer header');
+}, 'GET Navigation, same-origin with service worker that changes the ' +
+   'request sets correct origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'POST',
+                                            'change-request');
+  assert_equals(result.origin, SAME_ORIGIN.origin, 'origin header');
+  assert_equals(result.referer, script.href, 'referer header');
+}, 'POST Navigation, same-origin with service worker that changes the ' +
+   'request sets correct origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'no-sw');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, SAME_SITE.href, 'referer header');
+}, 'GET Navigation, same-site with no service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'POST',
+                                            'no-sw');
+  assert_equals(result.origin, SAME_SITE.origin, 'origin header');
+  assert_equals(result.referer, SAME_SITE.href, 'referer header');
+}, 'POST Navigation, same-site with no service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'passthrough');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, SAME_SITE.href, 'referer header');
+}, 'GET Navigation, same-site with passthrough service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'POST',
+                                            'passthrough');
+  assert_equals(result.origin, SAME_SITE.origin, 'origin header');
+  assert_equals(result.referer, SAME_SITE.href, 'referer header');
+}, 'POST Navigation, same-site with passthrough service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'fallback');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, SAME_SITE.href, 'referer header');
+}, 'GET Navigation, same-site with fallback service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'POST',
+                                            'fallback');
+  assert_equals(result.origin, SAME_SITE.origin, 'origin header');
+  assert_equals(result.referer, SAME_SITE.href, 'referer header');
+}, 'POST Navigation, same-site with fallback service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'navpreload');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, SAME_SITE.href, 'referer header');
+}, 'GET Navigation, same-site with navpreload service worker sets correct ' +
+   'origin and referer headers.');
+
+// There is no POST test for navpreload since the feature only supports GET
+// requests.
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'change-request');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, script.href, 'referer header');
+}, 'GET Navigation, same-site with service worker that changes the ' +
+   'request sets correct origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'POST',
+                                            'change-request');
+  assert_equals(result.origin, SAME_ORIGIN.origin, 'origin header');
+  assert_equals(result.referer, script.href, 'referer header');
+}, 'POST Navigation, same-site with service worker that changes the ' +
+   'request sets correct origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'no-sw');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, CROSS_SITE.href, 'referer header');
+}, 'GET Navigation, cross-site with no service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'POST',
+                                            'no-sw');
+  assert_equals(result.origin, CROSS_SITE.origin, 'origin header');
+  assert_equals(result.referer, CROSS_SITE.href, 'referer header');
+}, 'POST Navigation, cross-site with no service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'passthrough');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, CROSS_SITE.href, 'referer header');
+}, 'GET Navigation, cross-site with passthrough service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'POST',
+                                            'passthrough');
+  assert_equals(result.origin, CROSS_SITE.origin, 'origin header');
+  assert_equals(result.referer, CROSS_SITE.href, 'referer header');
+}, 'POST Navigation, cross-site with passthrough service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'fallback');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, CROSS_SITE.href, 'referer header');
+}, 'GET Navigation, cross-site with fallback service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'POST',
+                                            'fallback');
+  assert_equals(result.origin, CROSS_SITE.origin, 'origin header');
+  assert_equals(result.referer, CROSS_SITE.href, 'referer header');
+}, 'POST Navigation, cross-site with fallback service worker sets correct ' +
+   'origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'navpreload');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, CROSS_SITE.href, 'referer header');
+}, 'GET Navigation, cross-site with navpreload service worker sets correct ' +
+   'origin and referer headers.');
+
+// There is no POST test for navpreload since the feature only supports GET
+// requests.
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'change-request');
+  assert_equals(result.origin, 'not set', 'origin header');
+  assert_equals(result.referer, script.href, 'referer header');
+}, 'GET Navigation, cross-site with service worker that changes the ' +
+   'request sets correct origin and referer headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'POST',
+                                            'change-request');
+  assert_equals(result.origin, SAME_ORIGIN.origin, 'origin header');
+  assert_equals(result.referer, script.href, 'referer header');
+}, 'POST Navigation, cross-site with service worker that changes the ' +
+   'request sets correct origin and referer headers.');
+
+//
+// Sec-Fetch-* Headers (separated since not all browsers implement them)
+//
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'no-sw');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'GET Navigation, same-origin with no service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'POST',
+                                            'no-sw');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'POST Navigation, same-origin with no service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'passthrough');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'GET Navigation, same-origin with passthrough service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'POST',
+                                            'passthrough');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'POST Navigation, same-origin with passthrough service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'fallback');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'GET Navigation, same-origin with fallback service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'POST',
+                                            'fallback');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'POST Navigation, same-origin with fallback service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'navpreload');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'GET Navigation, same-origin with navpreload service worker sets correct ' +
+   'sec-fetch headers.');
+
+// There is no POST test for navpreload since the feature only supports GET
+// requests.
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'GET',
+                                            'change-request');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'same-origin', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'GET Navigation, same-origin with service worker that changes the ' +
+   'request sets correct sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_ORIGIN.hostname, 'POST',
+                                            'change-request');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'same-origin', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'POST Navigation, same-origin with service worker that changes the ' +
+   'request sets correct sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'no-sw');
+  assert_equals(result['sec-fetch-site'], 'same-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'GET Navigation, same-site with no service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'POST',
+                                            'no-sw');
+  assert_equals(result['sec-fetch-site'], 'same-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'POST Navigation, same-site with no service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'passthrough');
+  assert_equals(result['sec-fetch-site'], 'same-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'GET Navigation, same-site with passthrough service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'POST',
+                                            'passthrough');
+  assert_equals(result['sec-fetch-site'], 'same-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'POST Navigation, same-site with passthrough service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'fallback');
+  assert_equals(result['sec-fetch-site'], 'same-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'GET Navigation, same-site with fallback service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'POST',
+                                            'fallback');
+  assert_equals(result['sec-fetch-site'], 'same-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'POST Navigation, same-site with fallback service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'navpreload');
+  assert_equals(result['sec-fetch-site'], 'same-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'GET Navigation, same-site with navpreload service worker sets correct ' +
+   'sec-fetch headers.');
+
+// There is no POST test for navpreload since the feature only supports GET
+// requests.
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'GET',
+                                            'change-request');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'same-origin', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'GET Navigation, same-site with service worker that changes the ' +
+   'request sets correct sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, SAME_SITE.hostname, 'POST',
+                                            'change-request');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'same-origin', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'POST Navigation, same-site with service worker that changes the ' +
+   'request sets correct sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'no-sw');
+  assert_equals(result['sec-fetch-site'], 'cross-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'GET Navigation, cross-site with no service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'POST',
+                                            'no-sw');
+  assert_equals(result['sec-fetch-site'], 'cross-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'POST Navigation, cross-site with no service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'passthrough');
+  assert_equals(result['sec-fetch-site'], 'cross-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'GET Navigation, cross-site with passthrough service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'POST',
+                                            'passthrough');
+  assert_equals(result['sec-fetch-site'], 'cross-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'POST Navigation, cross-site with passthrough service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'fallback');
+  assert_equals(result['sec-fetch-site'], 'cross-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'GET Navigation, cross-site with fallback service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'POST',
+                                            'fallback');
+  assert_equals(result['sec-fetch-site'], 'cross-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'POST Navigation, cross-site with fallback service worker sets correct ' +
+   'sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'navpreload');
+  assert_equals(result['sec-fetch-site'], 'cross-site', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'navigate', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'iframe', 'sec-fetch-dest header');
+}, 'GET Navigation, cross-site with navpreload service worker sets correct ' +
+   'sec-fetch headers.');
+
+// There is no POST test for navpreload since the feature only supports GET
+// requests.
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'GET',
+                                            'change-request');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'same-origin', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'GET Navigation, cross-site with service worker that changes the ' +
+   'request sets correct sec-fetch headers.');
+
+promise_test(async t => {
+  const result = await post_and_get_headers(t, CROSS_SITE.hostname, 'POST',
+                                            'change-request');
+  assert_equals(result['sec-fetch-site'], 'same-origin', 'sec-fetch-site header');
+  assert_equals(result['sec-fetch-mode'], 'same-origin', 'sec-fetch-mode header');
+  assert_equals(result['sec-fetch-dest'], 'empty', 'sec-fetch-dest header');
+}, 'POST Navigation, cross-site with service worker that changes the ' +
+   'request sets correct sec-fetch headers.');
+
+promise_test(async t => {
+  await registration.unregister();
+}, 'Cleanup service worker');
+
+</script>
+</body>
diff --git a/testing/web-platform/tests/service-workers/service-worker/resources/fetch-rewrite-worker.js b/testing/web-platform/tests/service-workers/service-worker/resources/fetch-rewrite-worker.js
index 4631e83e0cea..20a80665270d 100644
--- a/testing/web-platform/tests/service-workers/service-worker/resources/fetch-rewrite-worker.js
+++ b/testing/web-platform/tests/service-workers/service-worker/resources/fetch-rewrite-worker.js
@@ -90,8 +90,12 @@ self.addEventListener('fetch', function(event) {
         var request = event.request;
         if (url) {
           request = new Request(url, init);
+        } else if (params['change-request']) {
+          request = new Request(request, init);
         }
-        fetch(request).then(function(response) {
+        const response_promise = params['navpreload'] ? event.preloadResponse
+                                                      : fetch(request);
+        response_promise.then(function(response) {
           var expectedType = params['expected_type'];
           if (expectedType && response.type !== expectedType) {
             // Resolve a JSON object with a failure instead of rejecting
diff --git a/testing/web-platform/tests/service-workers/service-worker/resources/fetch-rewrite-worker.js.headers b/testing/web-platform/tests/service-workers/service-worker/resources/fetch-rewrite-worker.js.headers
new file mode 100644
index 000000000000..123053b38c66
--- /dev/null
+++ b/testing/web-platform/tests/service-workers/service-worker/resources/fetch-rewrite-worker.js.headers
@@ -0,0 +1,2 @@
+Content-Type: text/javascript
+Service-Worker-Allowed: /
diff --git a/testing/web-platform/tests/service-workers/service-worker/resources/form-poster.html b/testing/web-platform/tests/service-workers/service-worker/resources/form-poster.html
new file mode 100644
index 000000000000..5d56fde19a8e
--- /dev/null
+++ b/testing/web-platform/tests/service-workers/service-worker/resources/form-poster.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<meta name="referrer" content="origin">
+<form method="POST" id="form"></form>
+<script>
+function onLoad() {
+  const params = new URLSearchParams(self.location.search);
+  const form = document.getElementById('form');
+  form.action = decodeURIComponent(params.get('target'));
+  form.submit();
+}
+self.addEventListener('load', onLoad);
+</script>
diff --git a/testing/web-platform/tests/service-workers/service-worker/resources/location-setter.html b/testing/web-platform/tests/service-workers/service-worker/resources/location-setter.html
new file mode 100644
index 000000000000..fae18e806655
--- /dev/null
+++ b/testing/web-platform/tests/service-workers/service-worker/resources/location-setter.html
@@ -0,0 +1,10 @@
+<!DOCTYPE html>
+<meta name="referrer" content="origin">
+<script>
+function onLoad() {
+  const params = new URLSearchParams(self.location.search);
+  const target = decodeURIComponent(params.get('target'));
+  self.location = target;
+}
+self.addEventListener('load', onLoad);
+</script>
diff --git a/testing/web-platform/tests/service-workers/service-worker/resources/navigation-headers-server.py b/testing/web-platform/tests/service-workers/service-worker/resources/navigation-headers-server.py
new file mode 100644
index 000000000000..5b2e044f8b52
--- /dev/null
+++ b/testing/web-platform/tests/service-workers/service-worker/resources/navigation-headers-server.py
@@ -0,0 +1,19 @@
+def main(request, response):
+    response.status = (200, b"OK")
+    response.headers.set(b"Content-Type", b"text/html")
+    return b"""
+    <script>
+      self.addEventListener('load', evt => {
+        self.parent.postMessage({
+          origin: '%s',
+          referer: '%s',
+          'sec-fetch-site': '%s',
+          'sec-fetch-mode': '%s',
+          'sec-fetch-dest': '%s',
+        });
+      });
+    </script>""" % (request.headers.get(
+        b"origin", b"not set"), request.headers.get(b"referer", b"not set"),
+                    request.headers.get(b"sec-fetch-site", b"not set"),
+                    request.headers.get(b"sec-fetch-mode", b"not set"),
+                    request.headers.get(b"sec-fetch-dest", b"not set"))
diff --git a/testing/web-platform/tests/service-workers/service-worker/resources/same-site-cookies-register.html b/testing/web-platform/tests/service-workers/service-worker/resources/same-site-cookies-register.html
new file mode 100644
index 000000000000..084f0a08a8e6
--- /dev/null
+++ b/testing/web-platform/tests/service-workers/service-worker/resources/same-site-cookies-register.html
@@ -0,0 +1,22 @@
+<!DOCTYPE html>
+<meta charset="utf-8"/>
+<script>
+async function onLoad() {
+  const scope = self.origin + '/cookies/resources/postToParent.py?with-sw';
+  const script = './fetch-rewrite-worker.js';
+  const reg = await navigator.serviceWorker.register(script, { scope: scope });
+  await new Promise(resolve => {
+    const worker = reg.installing;
+    worker.addEventListener('statechange', evt => {
+      if (worker.state === 'activated') {
+        resolve();
+      }
+    });
+  });
+  if (reg.navigationPreload) {
+    await reg.navigationPreload.enable();
+  }
+  window.opener.postMessage({ type: 'SW-REGISTERED' }, '*');
+}
+self.addEventListener('load', onLoad);
+</script>
diff --git a/testing/web-platform/tests/service-workers/service-worker/resources/same-site-cookies-unregister.html b/testing/web-platform/tests/service-workers/service-worker/resources/same-site-cookies-unregister.html
new file mode 100644
index 000000000000..cca3620b61e7
--- /dev/null
+++ b/testing/web-platform/tests/service-workers/service-worker/resources/same-site-cookies-unregister.html
@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<meta charset="utf-8"/>
+<script>
+async function onLoad() {
+  const scope = self.origin + '/cookies/resources/postToParent.py?with-sw';
+  const reg = await navigator.serviceWorker.getRegistration(scope);
+  await reg.unregister();
+  window.opener.postMessage({ type: 'SW-UNREGISTERED' }, '*');
+}
+self.addEventListener('load', onLoad);
+</script>
diff --git a/testing/web-platform/tests/service-workers/service-worker/same-site-cookies.https.html b/testing/web-platform/tests/service-workers/service-worker/same-site-cookies.https.html
new file mode 100644
index 000000000000..54c42c84d802
--- /dev/null
+++ b/testing/web-platform/tests/service-workers/service-worker/same-site-cookies.https.html
@@ -0,0 +1,215 @@
+<!DOCTYPE html>
+<meta charset="utf-8"/>
+<title>Service Worker: Same-site cookie behavior</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/common/get-host-info.sub.js"></script>
+<script src="/service-workers/service-worker/resources/test-helpers.sub.js"></script>
+<script src="/cookies/resources/cookie-helper.sub.js"></script>
+<body>
+<script>
+'use strict';
+async function unregister_service_worker(origin) {
+  const w = window.open(origin +
+      '/service-workers/service-worker/resources/same-site-cookies-unregister.html');
+  try {
+    await wait_for_message('SW-UNREGISTERED');
+  } finally {
+    w.close();
+  }
+}
+
+async function register_service_worker(origin) {
+  const w = window.open(origin +
+      '/service-workers/service-worker/resources/same-site-cookies-register.html');
+  try {
+    await wait_for_message('SW-REGISTERED');
+  } finally {
+    w.close();
+  }
+}
+
+async function run_test(t, origin, navaction, swaction, expected) {
+  const value = 'COOKIE_VALUE';
+  await resetSameSiteCookies(origin, value);
+  if (swaction === 'navpreload') {
+    assert_true('navigationPreload' in ServiceWorkerRegistration.prototype,
+                'navigation preload must be supported');
+  }
+  const sw_param = swaction === 'no-sw' ? 'no-sw' : 'with-sw';
+  let action_param = '';
+  if (swaction === 'fallback') {
+    action_param = '&ignore';
+  } else if (swaction !== 'no-sw') {
+    action_param = '&' + swaction;
+  }
+  const navpreload_param = swaction === 'navpreload' ? '&navpreload' : '';
+  const change_request_param = swaction === 'change-request' ? '&change-request' : '';
+  const target_string = origin + `/cookies/resources/postToParent.py?` +
+                                 `${sw_param}${action_param}`
+  const target_url = new URL(target_string);
+  if (navaction === 'window.open') {
+    const w = window.open(target_url);
+    t.add_cleanup(() => w.close());
+  } else if (navaction === 'form post') {
+    const poster_url =
+        `./resources/form-poster.html?target=${encodeURIComponent(target_url)}`;
+    const w = window.open(poster_url);
+    t.add_cleanup(() => w.close());
+  }
+  const result = await wait_for_message('COOKIES');
+  verifySameSiteCookieState(expected, value, result.data,
+                            DomSameSiteStatus.SAME_SITE);
+}
+
+promise_test(async t => {
+  await register_service_worker(self.origin);
+  await register_service_worker(SECURE_SUBDOMAIN_ORIGIN);
+  await register_service_worker(SECURE_CROSS_SITE_ORIGIN);
+}, 'Setup service workers');
+
+promise_test(t => {
+  return run_test(t, self.origin, 'window.open', 'no-sw',
+                  SameSiteStatus.STRICT);
+}, 'same-origin, window.open with no service worker');
+
+promise_test(t => {
+  return run_test(t, self.origin, 'window.open', 'fallback',
+                  SameSiteStatus.STRICT);
+}, 'same-origin, window.open with fallback');
+
+promise_test(t => {
+  return run_test(t, self.origin, 'window.open', 'passthrough',
+                  SameSiteStatus.STRICT);
+}, 'same-origin, window.open with passthrough');
+
+promise_test(t => {
+  return run_test(t, self.origin, 'window.open', 'change-request',
+                  SameSiteStatus.STRICT);
+}, 'same-origin, window.open with change-request');
+
+promise_test(t => {
+  return run_test(t, self.origin, 'window.open', 'navpreload',
+                  SameSiteStatus.STRICT);
+}, 'same-origin, window.open with navpreload');
+
+promise_test(t => {
+  return run_test(t, SECURE_SUBDOMAIN_ORIGIN, 'window.open', 'no-sw',
+                  SameSiteStatus.STRICT);
+}, 'same-site, window.open with no service worker');
+
+promise_test(t => {
+  return run_test(t, SECURE_SUBDOMAIN_ORIGIN, 'window.open', 'fallback',
+                  SameSiteStatus.STRICT);
+}, 'same-site, window.open with fallback');
+
+promise_test(t => {
+  return run_test(t, SECURE_SUBDOMAIN_ORIGIN, 'window.open', 'passthrough',
+                  SameSiteStatus.STRICT);
+}, 'same-site, window.open with passthrough');
+
+promise_test(t => {
+  return run_test(t, SECURE_SUBDOMAIN_ORIGIN, 'window.open', 'change-request',
+                  SameSiteStatus.STRICT);
+}, 'same-site, window.open with change-request');
+
+promise_test(t => {
+  return run_test(t, SECURE_SUBDOMAIN_ORIGIN, 'window.open', 'navpreload',
+                  SameSiteStatus.STRICT);
+}, 'same-site, window.open with navpreload');
+
+promise_test(t => {
+  return run_test(t, SECURE_CROSS_SITE_ORIGIN, 'window.open', 'no-sw',
+                  SameSiteStatus.LAX);
+}, 'cross-site, window.open with no service worker');
+
+promise_test(t => {
+  return run_test(t, SECURE_CROSS_SITE_ORIGIN, 'window.open', 'fallback',
+                  SameSiteStatus.LAX);
+}, 'cross-site, window.open with fallback');
+
+promise_test(t => {
+  return run_test(t, SECURE_CROSS_SITE_ORIGIN, 'window.open', 'passthrough',
+                  SameSiteStatus.LAX);
+}, 'cross-site, window.open with passthrough');
+
+promise_test(t => {
+  return run_test(t, SECURE_CROSS_SITE_ORIGIN, 'window.open', 'change-request',
+                  SameSiteStatus.STRICT);
+}, 'cross-site, window.open with change-request');
+
+promise_test(t => {
+  return run_test(t, SECURE_CROSS_SITE_ORIGIN, 'window.open', 'navpreload',
+                  SameSiteStatus.LAX);
+}, 'cross-site, window.open with navpreload');
+
+//
+// Form POST tests
+//
+promise_test(t => {
+  return run_test(t, self.origin, 'form post', 'no-sw', SameSiteStatus.STRICT);
+}, 'same-origin, form post with no service worker');
+
+promise_test(t => {
+  return run_test(t, self.origin, 'form post', 'fallback',
+                  SameSiteStatus.STRICT);
+}, 'same-origin, form post with fallback');
+
+promise_test(t => {
+  return run_test(t, self.origin, 'form post', 'passthrough',
+                  SameSiteStatus.STRICT);
+}, 'same-origin, form post with passthrough');
+
+promise_test(t => {
+  return run_test(t, self.origin, 'form post', 'change-request',
+                  SameSiteStatus.STRICT);
+}, 'same-origin, form post with change-request');
+
+promise_test(t => {
+  return run_test(t, SECURE_SUBDOMAIN_ORIGIN, 'form post', 'no-sw',
+                  SameSiteStatus.STRICT);
+}, 'same-site, form post with no service worker');
+
+promise_test(t => {
+  return run_test(t, SECURE_SUBDOMAIN_ORIGIN, 'form post', 'fallback',
+                  SameSiteStatus.STRICT);
+}, 'same-site, form post with fallback');
+
+promise_test(t => {
+  return run_test(t, SECURE_SUBDOMAIN_ORIGIN, 'form post', 'passthrough',
+                  SameSiteStatus.STRICT);
+}, 'same-site, form post with passthrough');
+
+promise_test(t => {
+  return run_test(t, SECURE_SUBDOMAIN_ORIGIN, 'form post', 'change-request',
+                  SameSiteStatus.STRICT);
+}, 'same-site, form post with change-request');
+
+promise_test(t => {
+  return run_test(t, SECURE_CROSS_SITE_ORIGIN, 'form post', 'no-sw',
+                  SameSiteStatus.CROSS_SITE);
+}, 'cross-site, form post with no service worker');
+
+promise_test(t => {
+  return run_test(t, SECURE_CROSS_SITE_ORIGIN, 'form post', 'fallback',
+                  SameSiteStatus.CROSS_SITE);
+}, 'cross-site, form post with fallback');
+
+promise_test(t => {
+  return run_test(t, SECURE_CROSS_SITE_ORIGIN, 'form post', 'passthrough',
+                  SameSiteStatus.CROSS_SITE);
+}, 'cross-site, form post with passthrough');
+
+promise_test(t => {
+  return run_test(t, SECURE_CROSS_SITE_ORIGIN, 'form post', 'change-request',
+                  SameSiteStatus.STRICT);
+}, 'cross-site, form post with change-request');
+
+promise_test(async t => {
+  await unregister_service_worker(self.origin);
+  await unregister_service_worker(SECURE_SUBDOMAIN_ORIGIN);
+  await unregister_service_worker(SECURE_CROSS_SITE_ORIGIN);
+}, 'Cleanup service workers');
+
+</script>
+</body>
