diff --git a/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-001.html b/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-001.html
new file mode 100644
index 00000000000000..e1495beb8b184d
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-001.html
@@ -0,0 +1,15 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: Choose browsing context - '_parent'</title>
+<link rel="author" title="Intel" href="http://www.intel.com/">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<div id="log"></div>
+<script>
+async_test(t => {
+  window.addEventListener('message', t.step_func_done(e => {
+    assert_equals(e.data.name, 'parentWin');
+  }));
+}, 'The parent browsing context must be chosen if the given name is `_parent`');
+</script>
+<iframe id="embedded" src="resources/parent-iframe-1.html" name="parentWin" style="display:none"></iframe>
diff --git a/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-002.html b/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-002.html
new file mode 100644
index 00000000000000..9cdef8349f38c1
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-002.html
@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: Choose browsing context - '_parent' (nested contexts)</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<div id="log"></div>
+<script>
+async_test(t => {
+  var topWindow;
+  t.add_cleanup(() => topWindow.close());
+  window.addEventListener('message', t.step_func_done(e => {
+    assert_equals(e.data.name, 'iframeParent');
+    assert_false(e.data.isTop, 'window.parent is not top');
+  }));
+  topWindow = window.open('resources/parent-top.html', '_blank');
+}, 'choosing _parent context: multiple nested contexts');
+</script>
diff --git a/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-003.html b/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-003.html
new file mode 100644
index 00000000000000..f0a165e6844c7a
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-003.html
@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: Choose browsing context - '_parent' (via window.open)</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<div id="log"></div>
+<script>
+async_test(t => {
+  var topWindow;
+  t.add_cleanup(() => topWindow.close());
+  window.addEventListener('message', t.step_func_done(e => {
+    assert_equals(e.data.name, 'parentTopReplace');
+    assert_equals(e.data.isTop, true);
+  }));
+  topWindow = window.open('resources/parent-top-replace.html', 'parentTopReplace');
+}, '_parent should reuse window.parent context');
+</script>
diff --git a/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-004.html b/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-004.html
new file mode 100644
index 00000000000000..ca98f66d172380
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/browsing-context-choose-parent-004.html
@@ -0,0 +1,16 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: Choose browsing context - '_parent' (case-sensitivity)</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<div id="log"></div>
+<iframe src="resources/parent-iframe-insensitive-1.html" name="parentWin" style="display:none"></iframe>
+
+<script>
+async_test(t => {
+  window.addEventListener('message', t.step_func_done(e => {
+    assert_equals(e.data.name, 'parentWin', "The browsing context name should be 'parentWin'.");
+    assert_equals(e.data.isTop, false);
+  }));
+}, 'choosing _parent context should be case-insensitive');
+</script>
diff --git a/html/browsers/windows/browsing-context-names/browsing-context-choose-parent.html b/html/browsers/windows/browsing-context-names/browsing-context-choose-parent.html
deleted file mode 100644
index c771a8fd71bbac..00000000000000
--- a/html/browsers/windows/browsing-context-names/browsing-context-choose-parent.html
+++ /dev/null
@@ -1,20 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>HTML Test: Choose browsing context - the given name is '_parent'</title>
-<link rel="author" title="Intel" href="http://www.intel.com/">
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<div id="log"></div>
-<iframe src="parent1.html" name="parentWin" style="display:none"></iframe>
-<script>
-
-var t = async_test("The parent browsing context must be chosen if the given name is '_parent'");
-
-window.addEventListener("message", function (e) {
-  t.step(function() {
-    assert_equals(e.data.name, "parentWin", "The browsing context name should be 'parentWin'.");
-  });
-  t.done();
-}, false);
-
-</script>
diff --git a/html/browsers/windows/browsing-context-names/existing.html b/html/browsers/windows/browsing-context-names/existing.html
index 13d2c6ab4e00c2..6023319cebfd31 100644
--- a/html/browsers/windows/browsing-context-names/existing.html
+++ b/html/browsers/windows/browsing-context-names/existing.html
@@ -5,7 +5,7 @@
 <script>
 
 function do_test() {
-  window.open("message.html", "existWin");
+  window.open("resources/post-to-top.html", "existWin");
 }
 
 </script>
diff --git a/html/browsers/windows/browsing-context-names/parent1.html b/html/browsers/windows/browsing-context-names/resources/parent-iframe-1.html
similarity index 77%
rename from html/browsers/windows/browsing-context-names/parent1.html
rename to html/browsers/windows/browsing-context-names/resources/parent-iframe-1.html
index fb34b2fe707922..3d7accffd7806e 100644
--- a/html/browsers/windows/browsing-context-names/parent1.html
+++ b/html/browsers/windows/browsing-context-names/resources/parent-iframe-1.html
@@ -2,4 +2,4 @@
 <meta charset="utf-8">
 <title>HTML Test: browsing context name - parent</title>
 <link rel="author" title="Intel" href="http://www.intel.com/">
-<iframe src="parent2.html"></iframe>
+<iframe src="parent-iframe-2.html"></iframe>
diff --git a/html/browsers/windows/browsing-context-names/parent2.html b/html/browsers/windows/browsing-context-names/resources/parent-iframe-2.html
similarity index 80%
rename from html/browsers/windows/browsing-context-names/parent2.html
rename to html/browsers/windows/browsing-context-names/resources/parent-iframe-2.html
index 34eb1c76bf55b7..81d0735c60970a 100644
--- a/html/browsers/windows/browsing-context-names/parent2.html
+++ b/html/browsers/windows/browsing-context-names/resources/parent-iframe-2.html
@@ -4,6 +4,6 @@
 <link rel="author" title="Intel" href="http://www.intel.com/">
 <script>
 
-window.open("message.html", "_parent");
+window.open("post-to-top.html", "_parent");
 
 </script>
diff --git a/html/browsers/windows/browsing-context-names/resources/parent-iframe-3.html b/html/browsers/windows/browsing-context-names/resources/parent-iframe-3.html
new file mode 100644
index 00000000000000..1412dc2e79b227
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/resources/parent-iframe-3.html
@@ -0,0 +1,6 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: browsing context name - parent</title>
+<script>
+window.open("post-to-opener.html", "_parent");
+</script>
diff --git a/html/browsers/windows/browsing-context-names/resources/parent-iframe-insensitive-1.html b/html/browsers/windows/browsing-context-names/resources/parent-iframe-insensitive-1.html
new file mode 100644
index 00000000000000..8ddbf44a3b5e40
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/resources/parent-iframe-insensitive-1.html
@@ -0,0 +1,4 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: browsing context name - parent</title>
+<iframe src="parent-iframe-insensitive-2.html"></iframe>
diff --git a/html/browsers/windows/browsing-context-names/resources/parent-iframe-insensitive-2.html b/html/browsers/windows/browsing-context-names/resources/parent-iframe-insensitive-2.html
new file mode 100644
index 00000000000000..38d6b2f42848a1
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/resources/parent-iframe-insensitive-2.html
@@ -0,0 +1,8 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: browsing context name - parent (case-insensitive)</title>
+<script>
+
+window.open("post-to-top-or-close.html", "_pARent");
+
+</script>
diff --git a/html/browsers/windows/browsing-context-names/resources/parent-top-nested.html b/html/browsers/windows/browsing-context-names/resources/parent-top-nested.html
new file mode 100644
index 00000000000000..ffe35113233935
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/resources/parent-top-nested.html
@@ -0,0 +1,4 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: browsing context name - parent: nested context</title>
+<iframe name="iframeChild" src="parent-iframe-2.html"></iframe>
diff --git a/html/browsers/windows/browsing-context-names/resources/parent-top-replace.html b/html/browsers/windows/browsing-context-names/resources/parent-top-replace.html
new file mode 100644
index 00000000000000..9b334c326693c0
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/resources/parent-top-replace.html
@@ -0,0 +1,4 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: browsing context name - parent: top-level context (gets replaced)</title>
+<iframe name="iframeOpener" src="parent-iframe-3.html"></iframe>
diff --git a/html/browsers/windows/browsing-context-names/resources/parent-top.html b/html/browsers/windows/browsing-context-names/resources/parent-top.html
new file mode 100644
index 00000000000000..6ad72f969be9cd
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/resources/parent-top.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: browsing context name - parent: top-level context</title>
+<iframe name="iframeParent" src="parent-top-nested.html"></iframe>
+<script>
+// Relay a message from child context to opener context
+window.addEventListener('message', e => {
+  if (window.opener) {
+    window.opener.postMessage(e.data, '*');
+  }
+});
+</script>
diff --git a/html/browsers/windows/browsing-context-names/resources/post-to-opener.html b/html/browsers/windows/browsing-context-names/resources/post-to-opener.html
new file mode 100644
index 00000000000000..3e9b7aaccb0dda
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/resources/post-to-opener.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: post window's name to top browsing context</title>
+<link rel="author" title="Intel" href="http://www.intel.com/">
+<script>
+if (window.opener) {
+  window.opener.postMessage({
+    name: window.name,
+    isTop: (window.top === window)
+  }, "*");
+}
+</script>
diff --git a/html/browsers/windows/browsing-context-names/resources/post-to-top-or-close.html b/html/browsers/windows/browsing-context-names/resources/post-to-top-or-close.html
new file mode 100644
index 00000000000000..2ccb6731d7ba44
--- /dev/null
+++ b/html/browsers/windows/browsing-context-names/resources/post-to-top-or-close.html
@@ -0,0 +1,16 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>HTML Test: post window's name to top browsing context</title>
+<link rel="author" title="Intel" href="http://www.intel.com/">
+<script>
+if (window.top === window) {
+  // This is an implicit failure; go ahead and close now
+  // so that this window isn't left hanging around
+  window.close();
+} else {
+  top.postMessage({
+    name: window.name,
+    isTop: (window.top === window)
+  }, "*");
+}
+</script>
diff --git a/html/browsers/windows/browsing-context-names/message.html b/html/browsers/windows/browsing-context-names/resources/post-to-top.html
similarity index 70%
rename from html/browsers/windows/browsing-context-names/message.html
rename to html/browsers/windows/browsing-context-names/resources/post-to-top.html
index 90720d46a9d090..aebb57b0197e3c 100644
--- a/html/browsers/windows/browsing-context-names/message.html
+++ b/html/browsers/windows/browsing-context-names/resources/post-to-top.html
@@ -3,7 +3,8 @@
 <title>HTML Test: post window's name to top browsing context</title>
 <link rel="author" title="Intel" href="http://www.intel.com/">
 <script>
-
-top.postMessage({name: window.name}, "*");
-
+top.postMessage({
+  name: window.name,
+  isTop: (window.top === window)
+}, "*");
 </script>
diff --git a/html/browsers/windows/browsing-context-names/self1.html b/html/browsers/windows/browsing-context-names/self1.html
index 2c8e3a414c94e2..d72df6f86420cb 100644
--- a/html/browsers/windows/browsing-context-names/self1.html
+++ b/html/browsers/windows/browsing-context-names/self1.html
@@ -5,7 +5,7 @@
 <script>
 
 window.name = "selfWin1";
-var win = window.open("message.html", "_self");
+var win = window.open("resources/post-to-top.html", "_self");
 win.close();
 
 </script>
diff --git a/html/browsers/windows/browsing-context-names/self2.html b/html/browsers/windows/browsing-context-names/self2.html
index 57276fadafe860..b3b4f59b535974 100644
--- a/html/browsers/windows/browsing-context-names/self2.html
+++ b/html/browsers/windows/browsing-context-names/self2.html
@@ -5,7 +5,7 @@
 <script>
 
 window.name = "selfWin2";
-var win = window.open("message.html", "");
+var win = window.open("resources/post-to-top.html", "");
 win.close();
 
 </script>
