diff --git a/resource-timing/embed-refresh.html b/resource-timing/embed-refresh.html
index cd4857de31d2ae..2a69bf6155bdb7 100644
--- a/resource-timing/embed-refresh.html
+++ b/resource-timing/embed-refresh.html
@@ -7,22 +7,27 @@
 <script src="/resources/testharnessreport.js"></script>
 <script>
     let t = async_test("Test that an HTML embed refreshes are not observable by the parent");
-    function verify_iframe_refresh_not_observable() {
+    const pre_refresh_url = new URL("resources/document-that-refreshes.html", location).href;
+    const post_refresh_url = new URL("resources/document-refreshed.html", location).href;
+    function verify_embed_refresh_not_observable() {
         let entries = performance.getEntriesByType("resource");
-        let found_first_iframe = false;
+        let found_first_embed = false;
         for (entry of entries) {
-            if (entry.name == "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-refreshes.html") {
-                found_first_iframe = true;
+            if (entry.name == pre_refresh_url) {
+                found_first_embed = true;
             }
-            assert_not_equals(entry.name, "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/refreshed_iframe.html", "Refreshed iframe should not be observable");
+            assert_not_equals(entry.name, post_refresh_url, "Refreshed embed should not be observable");
         }
-        assert_true(found_first_iframe, "Initial iframe should be observable");
+        assert_true(found_first_embed, "Initial embed should be observable");
         t.done();
     }
     window.addEventListener("message", t.step_func(e=>{
         if (e.data == "refreshed") {
-            verify_iframe_refresh_not_observable();
+            verify_embed_refresh_not_observable();
         }
     }));
 </script>
-<embed type="text/html" src="{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-refreshes.html">
+<embed type="text/html">
+<script>
+    document.getElementsByTagName("embed")[0].src = pre_refresh_url;
+</script>
diff --git a/resource-timing/embed-reload-back.html b/resource-timing/embed-reload-back.html
index f46c2eaaeffec2..87ca6672fabd81 100644
--- a/resource-timing/embed-reload-back.html
+++ b/resource-timing/embed-reload-back.html
@@ -6,8 +6,8 @@
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
 <script>
-    let t = async_test("Test that object reloads are not observable by the parent, even after history navigations");
-    window.open("resources/embed-reload-back.sub.html");
+    let t = async_test("Test that embed reloads are not observable by the parent, even after history navigations");
+    window.open("resources/embed-reload-back.html");
     addEventListener("message", t.step_func(e => {
         assert_equals(e.data, "PASS");
         t.done();
diff --git a/resource-timing/embed-reload.html b/resource-timing/embed-reload.html
index 74cdfc594dda77..f17102403c65c1 100644
--- a/resource-timing/embed-reload.html
+++ b/resource-timing/embed-reload.html
@@ -7,22 +7,27 @@
 <script src="/resources/testharnessreport.js"></script>
 <script>
     let t = async_test("Test that HTML embed reloads are not observable by the parent");
-    function verify_iframe_reload_not_observable() {
+    const pre_reload_url = new URL("resources/document-that-reloads.html", location).href;
+    const post_reload_url = new URL("resources/document-reloaded.html", location).href;
+    function verify_embed_reload_not_observable() {
         let entries = performance.getEntriesByType("resource");
-        let found_first_iframe = false;
+        let found_first_embed = false;
         for (entry of entries) {
-            if (entry.name == "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-reloads.html") {
-                found_first_iframe = true;
+            if (entry.name == pre_reload_url) {
+                found_first_embed = true;
             }
-            assert_not_equals(entry.name, "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/reloaded_iframe.html", "Reloaded iframe should not be observable");
+            assert_not_equals(entry.name, post_reload_url, "Reloaded embed should not be observable");
         }
-        assert_true(found_first_iframe, "Initial iframe should be observable");
+        assert_true(found_first_embed, "Initial embed should be observable");
         t.done();
     }
     window.addEventListener("message", t.step_func(e=>{
         if (e.data == "reloaded") {
-            verify_iframe_reload_not_observable();
+            verify_embed_reload_not_observable();
         }
     }));
 </script>
-<embed type="text/html" src="{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-reloads.html">
+<embed type="text/html">
+<script>
+    document.getElementsByTagName("embed")[0].src = pre_reload_url;
+</script>
diff --git a/resource-timing/iframe-refresh.html b/resource-timing/iframe-refresh.html
index ceefc8311d3173..2154aaffb220a9 100644
--- a/resource-timing/iframe-refresh.html
+++ b/resource-timing/iframe-refresh.html
@@ -7,14 +7,16 @@
 <script src="/resources/testharnessreport.js"></script>
 <script>
     let t = async_test("Test that iframe refreshes are not observable by the parent");
+    const pre_refresh_url = new URL("resources/document-that-refreshes.html", location).href;
+    const post_refresh_url = new URL("resources/document-refreshed.html", location).href;
     function verify_iframe_refresh_not_observable() {
         let entries = performance.getEntriesByType("resource");
         let found_first_iframe = false;
         for (entry of entries) {
-            if (entry.name == "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-refreshes.html") {
+            if (entry.name == pre_refresh_url) {
                 found_first_iframe = true;
             }
-            assert_not_equals(entry.name, "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/refreshed_iframe.html", "Refreshed iframe should not be observable");
+            assert_not_equals(entry.name, post_refresh_url, "Refreshed iframe should not be observable");
         }
         assert_true(found_first_iframe, "Initial iframe should be observable");
         t.done();
@@ -25,4 +27,7 @@
         }
     }));
 </script>
-<iframe src="{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-refreshes.html">
+<iframe></iframe>
+<script>
+    document.getElementsByTagName("iframe")[0].src = pre_refresh_url;
+</script>
diff --git a/resource-timing/iframe-reload-back.html b/resource-timing/iframe-reload-back.html
index ddf75a1c97dbd8..be6e6fac6e22b2 100644
--- a/resource-timing/iframe-reload-back.html
+++ b/resource-timing/iframe-reload-back.html
@@ -7,7 +7,7 @@
 <script src="/resources/testharnessreport.js"></script>
 <script>
     let t = async_test("Test that iframe reloads are not observable by the parent, even after history navigations");
-    window.open("resources/iframe-reload-back.sub.html");
+    window.open("resources/iframe-reload-back.html");
     addEventListener("message", t.step_func(e => {
         assert_equals(e.data, "PASS");
         t.done();
diff --git a/resource-timing/iframe-reload.html b/resource-timing/iframe-reload.html
index 0296ee05b252f4..d1d3e0795178a8 100644
--- a/resource-timing/iframe-reload.html
+++ b/resource-timing/iframe-reload.html
@@ -7,14 +7,16 @@
 <script src="/resources/testharnessreport.js"></script>
 <script>
     let t = async_test("Test that iframe reloads are not observable by the parent");
+    const pre_reload_url = new URL("resources/document-that-reloads.html", location).href;
+    const post_reload_url = new URL("resources/document-reloaded.html", location).href;
     function verify_iframe_reload_not_observable() {
         let entries = performance.getEntriesByType("resource");
         let found_first_iframe = false;
         for (entry of entries) {
-            if (entry.name == "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-reloads.html") {
+            if (entry.name == pre_reload_url) {
                 found_first_iframe = true;
             }
-            assert_not_equals(entry.name, "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/reloaded_iframe.html", "Reloaded iframe should not be observable.");
+            assert_not_equals(entry.name, post_reload_url, "Reloaded iframe should not be observable.");
         }
         assert_true(found_first_iframe, "Initial iframe should be observable");
         t.done();
@@ -25,4 +27,7 @@
         }
     }));
 </script>
-<iframe src="{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-reloads.html">
+<iframe></iframe>
+<script>
+    document.getElementsByTagName("iframe")[0].src = pre_reload_url;
+</script>
diff --git a/resource-timing/object-refresh.html b/resource-timing/object-refresh.html
index a51382f839d3a4..2535412155252f 100644
--- a/resource-timing/object-refresh.html
+++ b/resource-timing/object-refresh.html
@@ -7,22 +7,27 @@
 <script src="/resources/testharnessreport.js"></script>
 <script>
     let t = async_test("Test that object refreshes are not observable by the parent");
-    function verify_iframe_refresh_not_observable() {
+    const pre_refresh_url = new URL("resources/document-that-refreshes.html", location).href;
+    const post_refresh_url = new URL("resources/document-refreshed.html", location).href;
+    function verify_object_refresh_not_observable() {
         let entries = performance.getEntriesByType("resource");
-        let found_first_iframe = false;
+        let found_first_object = false;
         for (entry of entries) {
-            if (entry.name == "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-refreshes.html") {
-                found_first_iframe = true;
+            if (entry.name == pre_refresh_url) {
+                found_first_object = true;
             }
-            assert_not_equals(entry.name, "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/refreshed_iframe.html", "Refreshed object should not be observable");
+            assert_not_equals(entry.name, post_refresh_url, "Refreshed object should not be observable");
         }
-        assert_true(found_first_iframe, "Initial object should be observable");
+        assert_true(found_first_object, "Initial object should be observable");
         t.done();
     }
     window.addEventListener("message", t.step_func(e=>{
         if (e.data == "refreshed") {
-            verify_iframe_refresh_not_observable();
+            verify_object_refresh_not_observable();
         }
     }));
 </script>
-<object type="text/html" data="{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-refreshes.html">
+<object></object>
+<script>
+    document.getElementsByTagName("object")[0].data = pre_refresh_url;
+</script>
diff --git a/resource-timing/object-reload-back.html b/resource-timing/object-reload-back.html
index 7c91d25f15a26c..d1f296b2b6520f 100644
--- a/resource-timing/object-reload-back.html
+++ b/resource-timing/object-reload-back.html
@@ -7,7 +7,7 @@
 <script src="/resources/testharnessreport.js"></script>
 <script>
     let t = async_test("Test that object reloads are not observable by the parent, even after history navigations");
-    window.open("resources/object-reload-back.sub.html");
+    window.open("resources/object-reload-back.html");
     addEventListener("message", t.step_func(e => {
         assert_equals(e.data, "PASS");
         t.done();
diff --git a/resource-timing/object-reload.html b/resource-timing/object-reload.html
index 6954de59361241..b8afb383399746 100644
--- a/resource-timing/object-reload.html
+++ b/resource-timing/object-reload.html
@@ -7,22 +7,27 @@
 <script src="/resources/testharnessreport.js"></script>
 <script>
     let t = async_test("Test that object reloads are not observable by the parent");
-    function verify_iframe_reload_not_observable() {
+    const pre_reload_url = new URL("resources/document-that-reloads.html", location).href;
+    const post_reload_url = new URL("resources/document-reloaded.html", location).href;
+    function verify_object_reload_not_observable() {
         let entries = performance.getEntriesByType("resource");
-        let found_first_iframe = false;
+        let found_first_object = false;
         for (entry of entries) {
-            if (entry.name == "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-reloads.html") {
-                found_first_iframe = true;
+            if (entry.name == pre_reload_url) {
+                found_first_object = true;
             }
-            assert_not_equals(entry.name, "{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/reloaded_iframe.html", "Reloaded object should not be observable");
+            assert_not_equals(entry.name, post_reload_url, "Reloaded object should not be observable");
         }
-        assert_true(found_first_iframe, "Initial object should be observable");
+        assert_true(found_first_object, "Initial object should be observable");
         t.done();
     }
     window.addEventListener("message", t.step_func(e=>{
         if (e.data == "reloaded") {
-            verify_iframe_reload_not_observable();
+            verify_object_reload_not_observable();
         }
     }));
 </script>
-<object type="text/html" data="{{location[scheme]}}://{{host]}}:{{ports[http][0]}}/resource-timing/resources/iframe-that-reloads.html">
+<object></object>
+<script>
+    document.getElementsByTagName("object")[0].data = pre_reload_url;
+</script>