diff --git a/dom/base/test/file_bug1263696_frame_fail.html b/dom/base/test/file_bug1263696_frame_fail.html
new file mode 100644
index 000000000000..b45561aa6f72
--- /dev/null
+++ b/dom/base/test/file_bug1263696_frame_fail.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
+ "http://www.w3.org/TR/REC-html401-19991224/strict.dtd">
+<html>
+ <head>
+  <title>Bug 1263696 - iframe that should not be loaded</title>
+ </head>
+ <body>
+   <script>
+    parent.SimpleTest.ok(false, "this iframe should not load");
+   </script>
+ </body>
+</html>
diff --git a/dom/base/test/file_bug1263696_frame_pass.html b/dom/base/test/file_bug1263696_frame_pass.html
new file mode 100644
index 000000000000..7f49d6541c44
--- /dev/null
+++ b/dom/base/test/file_bug1263696_frame_pass.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
+ "http://www.w3.org/TR/REC-html401-19991224/strict.dtd">
+<html>
+ <head>
+  <title>Bug 1263696 - iframe that should be loaded</title>
+ </head>
+ <body>
+   <script>
+    parent.index = parent.index + 1;
+    parent.SimpleTest.ok(true, "this iframe should load");
+   </script>
+ </body>
+</html>
diff --git a/dom/base/test/mochitest.ini b/dom/base/test/mochitest.ini
index 368b0ae0b295..f6f548a8a6c3 100644
--- a/dom/base/test/mochitest.ini
+++ b/dom/base/test/mochitest.ini
@@ -125,6 +125,8 @@ support-files =
   file_bug902350_frame.html
   file_bug907892.html
   file_bug945152.jar
+  file_bug1263696_frame_pass.html
+  file_bug1263696_frame_fail.html
   file_bug1274806.html
   file_general_document.html
   file_htmlserializer_1.html
@@ -585,6 +587,7 @@ skip-if = toolkit == 'android'
 [test_bug1238440.html]
 [test_bug1250148.html]
 [test_bug1259588.html]
+[test_bug1263696.html]
 [test_bug1268962.html]
 [test_bug1274806.html]
 [test_bug1281963.html]
diff --git a/dom/base/test/test_bug1263696.html b/dom/base/test/test_bug1263696.html
new file mode 100644
index 000000000000..289a26ba4ff1
--- /dev/null
+++ b/dom/base/test/test_bug1263696.html
@@ -0,0 +1,53 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta><charset="utf-8"/>
+    <title>Test Embed/Object Node Conflicts</title>
+    <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+    <script type="application/javascript" src="plugin-utils.js"></script>
+    <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+    <script type="application/javascript">
+     SimpleTest.waitForExplicitFinish();
+     var index = 0;
+     function startTest() {
+       is(index, 12, "Should have loaded all passing frames.");
+       SimpleTest.finish();
+     }
+    </script>
+  </head>
+  <body onload="startTest()">
+    <object data="file_bug1263696_frame_pass.html" style="width: 100px; height: 100px">
+      <embed type="text/html" src="file_bug1263696_frame_fail.html" />
+    </object>
+    <object style="width: 100px; height: 100px" data="data:application/x-does-not-exist,test">
+      <embed type="text/html" src="file_bug1263696_frame_pass.html" />
+    </object>
+    <object style="width: 100px; height: 100px" data="data:application/x-does-not-exist,test">
+      <div></div>
+      <embed type="text/html" src="file_bug1263696_frame_pass.html" />
+    </object>
+    <object style="width: 100px; height: 100px" data="data:application/x-does-not-exist,test">
+      <div>
+        <embed type="text/html" src="file_bug1263696_frame_pass.html" />
+      </div>
+    </object>
+    <object style="width: 100px; height: 100px" data="data:application/x-does-not-exist,test">
+      <embed type="text/html" src="file_bug1263696_frame_pass.html" />
+      <embed type="text/html" src="file_bug1263696_frame_pass.html" />
+      <object data="file_bug1263696_frame_pass.html">
+        <embed type="text/html" src="file_bug1263696_frame_fail.html" />
+      </object>
+      <object data="data:application/x-does-not-exist,test">
+        <embed type="text/html" src="file_bug1263696_frame_pass.html" />
+      </object>
+    </object>
+    <div>
+      <object data="file_bug1263696_frame_pass.html" style="width: 100px; height: 100px"></object>
+      <embed type="text/html" src="file_bug1263696_frame_pass.html" />
+    </div>
+    <div>
+      <embed type="text/html" src="file_bug1263696_frame_pass.html" />
+      <object data="file_bug1263696_frame_pass.html" style="width: 100px; height: 100px"></object>
+    </div>
+  </body>
+</html>
diff --git a/testing/web-platform/meta/MANIFEST.json b/testing/web-platform/meta/MANIFEST.json
index d67063c5c539..e5269f7fc84b 100644
--- a/testing/web-platform/meta/MANIFEST.json
+++ b/testing/web-platform/meta/MANIFEST.json
@@ -51741,16 +51741,6 @@
      {}
     ]
    ],
-   "html/semantics/embedded-content/resources/should-load.html": [
-    [
-     {}
-    ]
-   ],
-   "html/semantics/embedded-content/resources/should-not-load.html": [
-    [
-     {}
-    ]
-   ],
    "html/semantics/embedded-content/svg/.gitkeep": [
     [
      {}
@@ -92201,12 +92191,6 @@
      {}
     ]
    ],
-   "html/semantics/embedded-content/the-embed-element/embed-in-object-fallback-2.html": [
-    [
-     "/html/semantics/embedded-content/the-embed-element/embed-in-object-fallback-2.html",
-     {}
-    ]
-   ],
    "html/semantics/embedded-content/the-embed-element/embed-in-object-fallback.html": [
     [
      "/html/semantics/embedded-content/the-embed-element/embed-in-object-fallback.html",
@@ -173860,14 +173844,6 @@
    "8840fa9072d9367f358721ed757bd3d23dd64967",
    "testharness"
   ],
-  "html/semantics/embedded-content/resources/should-load.html": [
-   "7cc95b9b2eb8c3f2d89278d22db271b9ae42e107",
-   "support"
-  ],
-  "html/semantics/embedded-content/resources/should-not-load.html": [
-   "a1657fc9e655ad0a30ced47a1412b6c34ba964b9",
-   "support"
-  ],
   "html/semantics/embedded-content/svg/.gitkeep": [
    "da39a3ee5e6b4b0d3255bfef95601890afd80709",
    "support"
@@ -174552,10 +174528,6 @@
    "94a08a7a5b5ec5c26f1974d5e5d8b4381a60baf5",
    "testharness"
   ],
-  "html/semantics/embedded-content/the-embed-element/embed-in-object-fallback-2.html": [
-   "a7da1fefb2403084205bf1ead77b422e69dc33b6",
-   "testharness"
-  ],
   "html/semantics/embedded-content/the-embed-element/embed-in-object-fallback-subdocument.html": [
    "1b60c4e5c8868fe87553b78047e711d63702a673",
    "support"
diff --git a/testing/web-platform/tests/html/semantics/embedded-content/resources/should-load.html b/testing/web-platform/tests/html/semantics/embedded-content/resources/should-load.html
deleted file mode 100644
index a9a178ce51ed..000000000000
--- a/testing/web-platform/tests/html/semantics/embedded-content/resources/should-load.html
+++ /dev/null
@@ -1,3 +0,0 @@
-<script>
-  parent.loadedCount++;
-</script>
diff --git a/testing/web-platform/tests/html/semantics/embedded-content/resources/should-not-load.html b/testing/web-platform/tests/html/semantics/embedded-content/resources/should-not-load.html
deleted file mode 100644
index 6281b2da5539..000000000000
--- a/testing/web-platform/tests/html/semantics/embedded-content/resources/should-not-load.html
+++ /dev/null
@@ -1,5 +0,0 @@
-<script>
-  parent.nestingTest.step(function() {
-    parent.assert_unreached(window.frameElement.getAttribute("test-description"));
-  });
-</script>
diff --git a/testing/web-platform/tests/html/semantics/embedded-content/the-embed-element/embed-in-object-fallback-2.html b/testing/web-platform/tests/html/semantics/embedded-content/the-embed-element/embed-in-object-fallback-2.html
deleted file mode 100644
index d904a7e1a1ca..000000000000
--- a/testing/web-platform/tests/html/semantics/embedded-content/the-embed-element/embed-in-object-fallback-2.html
+++ /dev/null
@@ -1,56 +0,0 @@
-<!doctype html>
-<html>
-  <head>
-    <meta charset=utf-8>
-    <title></title>
-    <script src=/resources/testharness.js></script>
-    <script src=/resources/testharnessreport.js></script>
-    <script>
-      var loadedCount = 0;
-      var nestingTest = async_test("Test <embed> nesting inside <object>");
-      onload = nestingTest.step_func_done(function() {
-        assert_equals(loadedCount, 12, "Should have loaded all should-load elements");
-      });
-    </script>
-    <style>
-      object, embed { display: none }
-    </style>
-  </head>
-  <body>
-    <object data="../resources/should-load.html" style="width: 100px; height: 100px">
-      <embed type="text/html" src="../resources/should-not-load.html"
-             test-description="<embed> inside <object>">
-    </object>
-    <object style="width: 100px; height: 100px" data="data:application/x-does-not-exist,test">
-      <embed type="text/html" src="../resources/should-load.html" />
-    </object>
-    <object style="width: 100px; height: 100px" data="data:application/x-does-not-exist,test">
-      <div></div>
-      <embed type="text/html" src="../resources/should-load.html" />
-    </object>
-    <object style="width: 100px; height: 100px" data="data:application/x-does-not-exist,test">
-      <div>
-        <embed type="text/html" src="../resources/should-load.html" />
-      </div>
-    </object>
-    <object style="width: 100px; height: 100px" data="data:application/x-does-not-exist,test">
-      <embed type="text/html" src="../resources/should-load.html" />
-      <embed type="text/html" src="../resources/should-load.html" />
-      <object data="../resources/should-load.html">
-        <embed type="text/html" src="../resources/should-not-load.html"
-               test-description="<embed> inside loaded <object> inside non-loaded <object>">
-      </object>
-      <object data="data:application/x-does-not-exist,test">
-        <embed type="text/html" src="../resources/should-load.html" />
-      </object>
-    </object>
-    <div>
-      <object data="../resources/should-load.html" style="width: 100px; height: 100px"></object>
-      <embed type="text/html" src="../resources/should-load.html" />
-    </div>
-    <div>
-      <embed type="text/html" src="../resources/should-load.html" />
-      <object data="../resources/should-load.html" style="width: 100px; height: 100px"></object>
-    </div>
-  </body>
-</html>
