Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

84 files changed, 9304 insertions, 0 deletions

diff --git a/dom/base/test/chrome/bug418986-1.js b/dom/base/test/chrome/bug418986-1.js
new file mode 100644
index 0000000000..7c39df0c13
--- /dev/null
+++ b/dom/base/test/chrome/bug418986-1.js
@@ -0,0 +1,88 @@
+/* globals chromeWindow */
+// The main test function.
+var test = function (isContent) {
+  SimpleTest.waitForExplicitFinish();
+
+  SpecialPowers.pushPrefEnv({
+    set: [["security.allow_eval_with_system_principal", true]],
+  });
+
+  if (!isContent) {
+    let { ww } = SpecialPowers.Services;
+    window.chromeWindow = ww.activeWindow;
+  }
+
+  // The pairs of values expected to be the same when
+  // fingerprinting resistance is enabled.
+  let pairs = [
+    ["screenX", 0],
+    ["screenY", 0],
+    ["mozInnerScreenX", 0],
+    ["mozInnerScreenY", 0],
+    ["screen.pixelDepth", 24],
+    ["screen.colorDepth", 24],
+    ["screen.availWidth", "innerWidth"],
+    ["screen.availHeight", "innerHeight"],
+    ["screen.left", 0],
+    ["screen.top", 0],
+    ["screen.availLeft", 0],
+    ["screen.availTop", 0],
+    ["screen.width", "innerWidth"],
+    ["screen.height", "innerHeight"],
+    ["screen.orientation.type", "'landscape-primary'"],
+    ["screen.orientation.angle", 0],
+    ["screen.mozOrientation", "'landscape-primary'"],
+    ["devicePixelRatio", 1],
+  ];
+
+  // checkPair: tests if members of pair [a, b] are equal when evaluated.
+  let checkPair = function (a, b) {
+    // eslint-disable-next-line no-eval
+    is(eval(a), eval(b), a + " should be equal to " + b);
+  };
+
+  // Returns generator object that iterates through pref values.
+  let prefVals = (function* () {
+    yield false;
+    yield true;
+  })();
+
+  // The main test function, runs until all pref values are exhausted.
+  let nextTest = function () {
+    let { value: prefValue, done } = prefVals.next();
+    if (done) {
+      SimpleTest.finish();
+      return;
+    }
+    SpecialPowers.pushPrefEnv(
+      { set: [["privacy.resistFingerprinting", prefValue]] },
+      function () {
+        // We will be resisting fingerprinting if the pref is enabled,
+        // and we are in a content script (not chrome).
+        let resisting = prefValue && isContent;
+        // Check each of the pairs.
+        pairs.map(function ([item, onVal]) {
+          if (resisting) {
+            checkPair("window." + item, onVal);
+          } else if (!isContent && !item.startsWith("moz")) {
+            checkPair("window." + item, "chromeWindow." + item);
+          }
+        });
+        if (!isContent && !resisting) {
+          // Hard to predict these values, but we can enforce constraints:
+          ok(
+            window.mozInnerScreenX >= chromeWindow.mozInnerScreenX,
+            "mozInnerScreenX"
+          );
+          ok(
+            window.mozInnerScreenY >= chromeWindow.mozInnerScreenY,
+            "mozInnerScreenY"
+          );
+        }
+        nextTest();
+      }
+    );
+  };
+
+  nextTest();
+};
diff --git a/dom/base/test/chrome/bug421622-referer.sjs b/dom/base/test/chrome/bug421622-referer.sjs
new file mode 100644
index 0000000000..14cab00de4
--- /dev/null
+++ b/dom/base/test/chrome/bug421622-referer.sjs
@@ -0,0 +1,9 @@
+function handleRequest(request, response) {
+  response.setHeader("Content-Type", "text/plain", false);
+  response.setHeader("Cache-Control", "no-cache", false);
+
+  var referer = request.hasHeader("Referer")
+    ? request.getHeader("Referer")
+    : "";
+  response.write("Referer: " + referer);
+}
diff --git a/dom/base/test/chrome/bug884693.sjs b/dom/base/test/chrome/bug884693.sjs
new file mode 100644
index 0000000000..f2650753f2
--- /dev/null
+++ b/dom/base/test/chrome/bug884693.sjs
@@ -0,0 +1,8 @@
+function handleRequest(request, response) {
+  let [status, statusText, encodedBody] = request.queryString.split("&");
+  let body = decodeURIComponent(encodedBody);
+  response.setStatusLine(request.httpVersion, status, statusText);
+  response.setHeader("Content-Type", "text/xml", false);
+  response.setHeader("Content-Length", "" + body.length, false);
+  response.write(body);
+}
diff --git a/dom/base/test/chrome/chrome.toml b/dom/base/test/chrome/chrome.toml
new file mode 100644
index 0000000000..b8439a2d2e
--- /dev/null
+++ b/dom/base/test/chrome/chrome.toml
@@ -0,0 +1,135 @@
+[DEFAULT]
+skip-if = ["os == 'android'"]
+support-files = [
+  "bug418986-1.js",
+  "clonedoc/**",
+  "file_bug549682.xhtml",
+  "file_bug616841.xhtml",
+  "file_bug816340.xhtml",
+  "file_bug990812-1.xhtml",
+  "file_bug990812-2.xhtml",
+  "file_bug990812-3.xhtml",
+  "file_bug990812-4.xhtml",
+  "file_bug990812-5.xhtml",
+  "file_bug1139964.xhtml",
+  "file_bug1209621.xhtml",
+  "fileconstructor_file.png",
+  "frame_custom_element_content.html",
+  "custom_element_ep.js",
+  "window_nsITextInputProcessor.xhtml",
+  "title_window.xhtml",
+  "window_swapFrameLoaders.xhtml",
+]
+prefs = ["gfx.font_rendering.fallback.async=false"]
+
+["test_bug120684.xhtml"]
+
+["test_bug206691.xhtml"]
+
+["test_bug289714.xhtml"]
+
+["test_bug339494.xhtml"]
+
+["test_bug357450.xhtml"]
+support-files = ["../file_bug357450.js"]
+
+["test_bug380418.html"]
+
+["test_bug383430.html"]
+
+["test_bug418986-1.xhtml"]
+
+["test_bug421622.xhtml"]
+
+["test_bug429785.xhtml"]
+
+["test_bug430050.xhtml"]
+
+["test_bug467123.xhtml"]
+
+["test_bug473284.xhtml"]
+
+["test_bug549682.xhtml"]
+skip-if = ["verify"]
+
+["test_bug571390.xhtml"]
+
+["test_bug616841.xhtml"]
+
+["test_bug635835.xhtml"]
+
+["test_bug682305.html"]
+
+["test_bug683852.xhtml"]
+
+["test_bug752226-3.xhtml"]
+
+["test_bug752226-4.xhtml"]
+
+["test_bug765993.html"]
+
+["test_bug780199.xhtml"]
+
+["test_bug780529.xhtml"]
+
+["test_bug800386.xhtml"]
+
+["test_bug816340.xhtml"]
+
+["test_bug884693.xhtml"]
+
+["test_bug914381.html"]
+
+["test_bug990812.xhtml"]
+
+["test_bug1063837.xhtml"]
+
+["test_bug1098074_throw_from_ReceiveMessage.xhtml"]
+
+["test_bug1139964.xhtml"]
+
+["test_bug1209621.xhtml"]
+
+["test_bug1339722.html"]
+
+["test_bug1346936.html"]
+
+["test_bug380418.html^headers^"]
+
+["test_chromeOuterWindowID.xhtml"]
+support-files = ["window_chromeOuterWindowID.xhtml"]
+
+["test_custom_element_content.xhtml"]
+
+["test_custom_element_ep.xhtml"]
+
+["test_document-element-inserted.xhtml"]
+support-files = [
+  "file_document-element-inserted.xhtml",
+  "file_document-element-inserted-inner.xhtml",
+]
+
+["test_domparsing.xhtml"]
+
+["test_fileconstructor.xhtml"]
+
+["test_getElementsWithGrid.html"]
+
+["test_input_value_set_preserve_undo.xhtml"]
+
+["test_nsITextInputProcessor.xhtml"]
+
+["test_nsITextInputProcessorCallback_at_changing_default_value_of_textarea.html"]
+
+["test_permission_hasValidTransientUserActivation.xhtml"]
+support-files = ["../dummy.html"]
+
+["test_range_getClientRectsAndTexts.html"]
+
+["test_swapFrameLoaders.xhtml"]
+skip-if = ["os == 'mac'"] # bug 1674413
+
+["test_title.xhtml"]
+support-files = ["file_title.xhtml"]
+
+["test_windowroot.xhtml"]
diff --git a/dom/base/test/chrome/clonedoc/chrome.manifest b/dom/base/test/chrome/clonedoc/chrome.manifest
new file mode 100644
index 0000000000..5d7e720416
--- /dev/null
+++ b/dom/base/test/chrome/clonedoc/chrome.manifest
@@ -0,0 +1 @@
+content clonedoc content/
diff --git a/dom/base/test/chrome/clonedoc/content/doc.xml b/dom/base/test/chrome/clonedoc/content/doc.xml
new file mode 100644
index 0000000000..fdd7e7c6e0
--- /dev/null
+++ b/dom/base/test/chrome/clonedoc/content/doc.xml
@@ -0,0 +1,4 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<something>
+  <somethinglese/>
+</something>
diff --git a/dom/base/test/chrome/custom_element_ep.js b/dom/base/test/chrome/custom_element_ep.js
new file mode 100644
index 0000000000..d933ecbbab
--- /dev/null
+++ b/dom/base/test/chrome/custom_element_ep.js
@@ -0,0 +1,14 @@
+/* globals finishTest */
+class XFoo extends HTMLElement {
+  constructor() {
+    super();
+    this.magicNumber = 42;
+  }
+
+  connectedCallback() {
+    finishTest(this.magicNumber === 42);
+  }
+}
+customElements.define("x-foo", XFoo);
+
+document.firstChild.appendChild(document.createElement("x-foo"));
diff --git a/dom/base/test/chrome/file_bug1139964.xhtml b/dom/base/test/chrome/file_bug1139964.xhtml
new file mode 100644
index 0000000000..8bf7f27e0b
--- /dev/null
+++ b/dom/base/test/chrome/file_bug1139964.xhtml
@@ -0,0 +1,60 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1139964
+-->
+<window title="Mozilla Bug 1139964"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="run()">
+  <label value="Mozilla Bug 1139964"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+  /* global messageManager, sendAsyncMessage */
+  var ppm = Cc["@mozilla.org/parentprocessmessagemanager;1"].getService();
+
+  function ok(cond, msg) {
+    window.arguments[0].ok(cond, msg);
+  }
+
+  var msgName = "TEST:Global_has_Promise";
+
+  function mmScriptForPromiseTest() {
+    /* eslint-env mozilla/process-script */
+    sendAsyncMessage("TEST:Global_has_Promise",
+                     {
+                       hasPromise: ("Promise" in this),
+                       hasTextEncoder: ("TextEncoder" in this),
+                       hasWindow: ("Window" in this),
+                     });
+  }
+
+  function processListener(m) {
+    ppm.removeMessageListener(msgName, processListener);
+    ok(m.data.hasPromise, "ProcessGlobal should have Promise object in the global scope!");
+    ok(m.data.hasTextEncoder, "ProcessGlobal should have TextEncoder object in the global scope!");
+    ok(m.data.hasWindow, "ProcessGlobal should have Window object in the global scope!");
+
+    messageManager.addMessageListener(msgName, tabListener)
+    messageManager.loadFrameScript("data:,(" + mmScriptForPromiseTest.toString() + ")()", true);
+  }
+
+  function tabListener(m) {
+    messageManager.removeMessageListener(msgName, tabListener);
+    ok(m.data.hasPromise, "BrowserChildGlobal should have Promise object in the global scope!");
+    ok(m.data.hasTextEncoder, "BrowserChildGlobal should have TextEncoder object in the global scope!");
+    ok(m.data.hasWindow, "BrowserChildGlobal should have Window object in the global scope!");
+
+    window.arguments[0].setTimeout(function() { this.done(); }, 0);
+    window.close();
+  }
+
+  function run() {
+    ppm.addMessageListener(msgName, processListener)
+    ppm.loadProcessScript("data:,(" + mmScriptForPromiseTest.toString() + ")()", true);
+  }
+
+  ]]></script>
+  <browser type="content" src="about:blank" id="ifr"/>
+</window>
diff --git a/dom/base/test/chrome/file_bug1209621.xhtml b/dom/base/test/chrome/file_bug1209621.xhtml
new file mode 100644
index 0000000000..3ba58975bd
--- /dev/null
+++ b/dom/base/test/chrome/file_bug1209621.xhtml
@@ -0,0 +1,85 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1209621
+-->
+<window title="Mozilla Bug 1209621"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="run()">
+  <label value="Mozilla Bug 1209621"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+  function ok(cond, msg) {
+    window.arguments[0].ok(cond, msg);
+  }
+
+  function is(actual, expected, msg) {
+    window.arguments[0].is(actual, expected, msg);
+  }
+
+  function run() {
+    var docshell = window.docShell;
+    ok(docshell, "Active window should have a DocShell");
+    var treeOwner = docshell.treeOwner;
+    ok(treeOwner, "Active docshell should have a TreeOwner!");
+
+    is(treeOwner.primaryContentShell, null,
+       "There shouldn't be primaryContentShell because no browser has primary=true.");
+    is(treeOwner.primaryRemoteTab, null,
+       "There shouldn't be primaryRemoteTab because no remote browser has primary=true.");
+    is(treeOwner.primaryContentBrowsingContext, null,
+       "There shouldn't be primaryContentBrowsingContext because no browser has primary=true.");
+
+    var ip = document.getElementById("inprocess");
+    var remote = document.getElementById("remote");
+    var remote2 = document.getElementById("remote2");
+
+    ip.setAttribute("primary", "true");
+    ok(ip.docShell, "non-remote browser should have a DocShell.");
+    is(treeOwner.primaryContentShell, ip.docShell,
+       "primary browser should be the primaryContentShell.");
+    is(treeOwner.primaryRemoteTab, null,
+       "There shouldn't be primaryRemoteTab because no remote browser has primary=true.");
+    is(treeOwner.primaryContentBrowsingContext, ip.browsingContext,
+       "primary browsing context should be the primaryContentBrowsingContext.");
+
+    ip.removeAttribute("primary");
+    remote.setAttribute("primary", "true");
+    is(treeOwner.primaryContentShell, null,
+       "There shouldn't be primaryContentShell because no browser has primary=true.");
+    var tp = remote.frameLoader.remoteTab;
+    ok(tp, "Remote browsers should have a remoteTab.");
+    is(treeOwner.primaryRemoteTab, tp,
+       "primary remote browser should be the primaryRemoteTab.");
+    is(treeOwner.primaryContentBrowsingContext, remote.browsingContext,
+       "primary remote browser should be the primaryContentBrowsingContext.");
+
+    remote.removeAttribute("primary");
+    is(treeOwner.primaryContentShell, null,
+       "There shouldn't be primaryContentShell because no browser has primary=true.");
+    is(treeOwner.primaryRemoteTab, null,
+       "There shouldn't be primaryRemoteTab because no remote browser has primary=true.");
+    is(treeOwner.primaryContentBrowsingContext, null,
+       "There shouldn't be primaryContentBrowsingContext because no browser has primary=true.");
+
+    remote2.setAttribute("primary", "true");
+    var tp2 = remote2.frameLoader.remoteTab;
+    ok(tp2, "Remote browsers should have a remoteTab.");
+    is(treeOwner.primaryRemoteTab, tp2,
+       "primary remote browser should be the primaryRemoteTab.");
+    is(treeOwner.primaryContentShell, null,
+       "There shouldn't be primaryContentShell because no browser has primary=true.");
+    is(treeOwner.primaryContentBrowsingContext, remote2.browsingContext,
+       "primary remote browser should be the primaryContentBrowsingContext.");
+
+    window.arguments[0].setTimeout(function() { this.done(); }, 0);
+    window.close();
+  }
+
+  ]]></script>
+  <browser type="content" src="about:blank" id="inprocess"/>
+  <browser type="content" remote="true" src="about:blank" id="remote"/>
+  <browser type="content" remote="true" src="about:blank" id="remote2"/>
+</window>
diff --git a/dom/base/test/chrome/file_bug549682.xhtml b/dom/base/test/chrome/file_bug549682.xhtml
new file mode 100644
index 0000000000..8ae05d38d8
--- /dev/null
+++ b/dom/base/test/chrome/file_bug549682.xhtml
@@ -0,0 +1,214 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=549682
+-->
+<window title="Mozilla Bug 549682"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="run()">
+  <label value="Mozilla Bug 549682"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+  /* global messageManager, sendAsyncMessage */
+  var didRunAsync = false;
+  var didRunLocal = false;
+
+  var global = Cc["@mozilla.org/globalmessagemanager;1"].getService();
+  var ppm = Cc["@mozilla.org/parentprocessmessagemanager;1"].getService();
+  var cpm = Cc["@mozilla.org/childprocessmessagemanager;1"].getService();
+
+  function ok(cond, msg) {
+    window.arguments[0].ok(cond, msg);
+  }
+
+  function is(actual, expected, msg) {
+    window.arguments[0].is(actual, expected, msg);
+  }
+
+  var asyncPPML = false;
+  function ppmASL(m) {
+    asyncPPML = true;
+  }
+  var syncPPML = false;
+  function ppmSL(m) {
+    syncPPML = true;
+  }
+  ppm.addMessageListener("processmessageAsync", ppmASL);
+  ppm.addMessageListener("processmessageSync", ppmSL);
+
+  cpm.sendAsyncMessage("processmessageAsync", "");
+  cpm.sendSyncMessage("processmessageSync", "");
+
+  var asyncCPML = false;
+  function cpmASL(m) {
+    asyncCPML = true;
+  }
+  cpm.addMessageListener("childprocessmessage", cpmASL);
+  ppm.broadcastAsyncMessage("childprocessmessage", "");
+
+  function checkPMMMessages() {
+    ok(asyncPPML, "should have handled async message");
+    ok(syncPPML, "should have handled sync message");
+    ok(asyncCPML, "should have handled async message");
+    ppm.removeMessageListener("processmessageAsync", ppmASL);
+    ppm.removeMessageListener("processmessageSync", ppmSL);
+    cpm.removeMessageListener("childprocessmessage", cpmASL);
+  }
+
+  var globalListenerCallCount = 0;
+  function globalListener(m) {
+    ++globalListenerCallCount;
+    if (m.name == "sync") {
+      global.removeMessageListener("async", globalListener);
+      global.removeMessageListener("sync", globalListener);
+      global.removeMessageListener("global-sync", globalListener);
+      // Note, the result depends on what other windows are open.
+      ok(globalListenerCallCount >= 4,
+         "Global listener should have been called at least 4 times!");
+      ok(didRunLocal, "Local message received.");
+    }
+  }
+
+  function asyncL(m) {
+    didRunAsync = true;
+    is(m.name, "async", "Wrong message!");
+    is(m.json.data, 1234, "Wrong data!");
+  }
+
+  function syncL(m) {
+    is(m.name, "sync", "Wrong message!");
+    is(m.json.data, 1234, "Wrong data!");
+    ok(didRunAsync, "Should have run async!");
+  }
+
+  function localL(m) {
+    is(m.name, "lasync", "Wrong message!");
+    is(m.json.data, 2345, "Wrong data!");
+    didRunLocal = true;
+  }
+
+  var weakMessageReceived = false;
+  var weakListener = {
+    QueryInterface: ChromeUtils.generateQI(["nsISupportsWeakReference"]),
+
+    receiveMessage(msg) {
+      if (weakMessageReceived) {
+        ok(false, 'Weak listener fired twice.');
+        return;
+      }
+
+      ok(true, 'Weak listener fired once.');
+      weakMessageReceived = true;
+      document.getElementById('ifr').messageManager
+              .removeWeakMessageListener('weak', weakListener);
+    }
+  };
+
+  var weakListener2 = {
+    QueryInterface: ChromeUtils.generateQI(["nsISupportsWeakReference"]),
+
+    receiveMessage(msg) {
+      ok(false, 'Should not have received a message.');
+    }
+  };
+
+  function weakDoneListener() {
+    ok(weakMessageReceived, 'Got "weak" message.');
+    finish();
+  }
+
+  function finish() {
+    window.arguments[0].setTimeout(function() { this.done(); }, 0);
+    var i = document.getElementById("ifr");
+    i.remove(); // This is a crash test!
+    window.close();
+  }
+
+  function loadScript() {
+    // Async should be processed first!
+    messageManager.loadFrameScript("data:,\
+      sendAsyncMessage('async', { data: 1234 });\
+      sendSyncMessage('sync', { data: 1234 });\
+      sendAsyncMessage('weak', {});\
+      sendAsyncMessage('weak', {});\
+      sendAsyncMessage('weakdone', {});", false);
+  }
+
+  function run() {
+    var localmm = document.getElementById('ifr').messageManager;
+
+    var docShell = document.getElementById('ifr').contentWindow.docShell;
+    ok(docShell, "Should have docshell");
+    var cfmm = docShell.messageManager;
+    ok(cfmm, "Should have content messageManager");
+
+    var didGetSyncMessage = false;
+    function syncContinueTestFn() {
+      didGetSyncMessage = true;
+    }
+    localmm.addMessageListener("syncContinueTest", syncContinueTestFn);
+    cfmm.sendSyncMessage("syncContinueTest", {});
+    localmm.removeMessageListener("syncContinueTest", syncContinueTestFn);
+    ok(didGetSyncMessage, "Should have got sync message!");
+
+    localmm.addMessageListener("lasync", localL);
+    localmm.loadFrameScript("data:,sendAsyncMessage('lasync', { data: 2345 })", false);
+
+    messageManager.addMessageListener("async", asyncL);
+    messageManager.addMessageListener("sync", syncL);
+    global.addMessageListener("async", globalListener);
+    global.addMessageListener("sync", globalListener);
+    global.addMessageListener("global-sync", globalListener);
+    global.loadFrameScript("data:,sendSyncMessage('global-sync', { data: 1234 });", true);
+    var toBeRemovedScript = "data:,sendAsyncMessage('toberemoved', { data: 2345 })";
+    var c = 0;
+    messageManager.addMessageListener("toberemoved", function() {
+      ++c;
+      is(c, 1, "Should be called only once!");
+    });
+    // This loads the script in the existing <browser>
+    messageManager.loadFrameScript(toBeRemovedScript, true);
+    // But it won't be loaded in the dynamically created <browser>
+    messageManager.removeDelayedFrameScript(toBeRemovedScript);
+
+    var oldValue = globalListenerCallCount;
+    var b = document.createXULElement("browser");
+    b.setAttribute("type", "content");
+    document.documentElement.appendChild(b);
+    is(globalListenerCallCount, oldValue + 1,
+                              "Wrong message count");
+
+    localmm.addWeakMessageListener('weak', weakListener);
+    localmm.addMessageListener('weakdone', weakDoneListener);
+
+    // Add weakListener2 as a weak message listener, then force weakListener2
+    // to be gc'ed.  weakListener2 shouldn't be run.
+    var weakRef = Cu.getWeakReference(weakListener2);
+    localmm.addWeakMessageListener('weak', weakListener2);
+    weakListener2 = null;
+
+    // Force a gc/cc in a loop until weakRef's referent has gone away.
+    function waitForWeakRefToDie() {
+      if (weakRef.get()) {
+        var mgr = Cc["@mozilla.org/memory-reporter-manager;1"]
+                    .getService(Ci.nsIMemoryReporterManager);
+        mgr.minimizeMemoryUsage(waitForWeakRefToDie);
+
+        // Print a message so that if the test hangs in a minimizeMemoryUsage
+        // loop, we'll be able to see it in the log.
+        ok(true, "waitForWeakRefToDie spinning...");
+        return;
+      }
+
+      setTimeout(checkPMMMessages, 0);
+      setTimeout(loadScript, 0);
+    }
+
+    waitForWeakRefToDie();
+  }
+
+  ]]></script>
+  <browser type="content" src="about:blank" id="ifr"/>
+</window>
diff --git a/dom/base/test/chrome/file_bug616841.xhtml b/dom/base/test/chrome/file_bug616841.xhtml
new file mode 100644
index 0000000000..b0512d162c
--- /dev/null
+++ b/dom/base/test/chrome/file_bug616841.xhtml
@@ -0,0 +1,63 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=616841
+-->
+<window title="Mozilla Bug 616841"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="start()">
+  <label value="Mozilla Bug 616841"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    /* global messageManager, sendAsyncMessage */
+    const FRAME_SCRIPT =
+"data:,addMessageListener(\n"+
+"  'cmp',\n"+
+"  function (m) {\n"+
+"    sendAsyncMessage('cmp', { i: m.json.i,\n"+
+"                              cmp: m.json.a.localeCompare(m.json.b) });\n"+
+"  });\n"+
+"sendAsyncMessage('contentReady');";
+
+    var toCompare = [ [ "C", "D" ],
+                      [ "D", "C" ],
+                      [ "\u010C", "D" ],
+                      [ "D", "\u010C" ] ];
+    var nCmps = 0;
+
+    function recvContentReady(m) {
+      for (var i = 0; i < toCompare.length; ++i) {
+        var pair = toCompare[i];
+        messageManager.broadcastAsyncMessage("cmp",
+                                             { i, a: pair[0], b: pair[1] });
+      }
+    }
+
+    function recvCmp(m) {
+      var i = m.json.i, cmp = m.json.cmp;
+      var pair = toCompare[i];
+      window.arguments[0].is(pair[0].localeCompare(pair[1]), cmp, "localeCompare returned same result in frame script");
+
+      if (toCompare.length == ++nCmps) {
+         messageManager.removeMessageListener("cmp", recvCmp);
+        finish();
+      }
+    }
+
+    function start() {
+      messageManager.addMessageListener("contentReady", recvContentReady);
+      messageManager.addMessageListener("cmp", recvCmp);
+      messageManager.loadFrameScript(FRAME_SCRIPT, true);
+    }
+
+    function finish() {
+      window.arguments[0].setTimeout(function() { this.done(); }, 0);
+      window.close();
+    }
+
+  ]]></script>
+
+  <browser id="browser" type="content" src="about:blank"/>
+</window>
diff --git a/dom/base/test/chrome/file_bug816340.xhtml b/dom/base/test/chrome/file_bug816340.xhtml
new file mode 100644
index 0000000000..0b1a9adcab
--- /dev/null
+++ b/dom/base/test/chrome/file_bug816340.xhtml
@@ -0,0 +1,69 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=816340
+-->
+<window title="Mozilla Bug 816340"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="start();">
+  <label value="Mozilla Bug 816340"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+    function ok(val, msg) {
+      window.arguments[0].ok(val, msg);
+    }
+
+    var elems =
+      [
+        "input",
+        "textarea",
+        "select",
+        "button",
+      ];
+
+    var chromeDidGetEvent = false;
+    function chromeListener() {
+      chromeDidGetEvent = true;
+    }
+
+    function testElement(el, disabled, contentShouldGetEvent) {
+      chromeDidGetEvent = false;
+      var b = document.getElementById("browser");
+      b.contentDocument.body.innerHTML = null;
+      var e = b.contentDocument.createElement(el);
+      if (disabled) {
+        e.setAttribute("disabled", "true");
+      }
+      b.contentDocument.body.appendChild(e);
+      var contentDidGetEvent = false;
+      b.contentDocument.body.addEventListener("foo",
+        function() { contentDidGetEvent = true }, true);
+
+      b.addEventListener("foo", chromeListener, true);
+      e.dispatchEvent(new Event("foo"));
+      b.removeEventListener("foo", chromeListener, true);
+      ok(contentDidGetEvent == contentShouldGetEvent, "content: " + el + (disabled ? " disabled" : ""));
+      ok(chromeDidGetEvent, "chrome: " + el + (disabled ? " disabled" : ""));
+    }
+
+    function start() {
+      // Test common element.
+      testElement("div", false, true);
+      testElement("div", true, true);
+
+      for (var i = 0; i < elems.length; ++i) {
+        testElement(elems[i], false, true);
+        testElement(elems[i], true, false);
+      }
+      ok(true, "done");
+      window.arguments[0].setTimeout(function() { this.done(); }, 0);
+      window.close();
+    }
+
+  ]]></script>
+
+  <browser id="browser" type="content" src="about:blank"/>
+</window>
diff --git a/dom/base/test/chrome/file_bug990812-1.xhtml b/dom/base/test/chrome/file_bug990812-1.xhtml
new file mode 100644
index 0000000000..8b8da3d136
--- /dev/null
+++ b/dom/base/test/chrome/file_bug990812-1.xhtml
@@ -0,0 +1,61 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=990812
+-->
+<window title="Mozilla Bug 990812"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="start();">
+  <label value="Mozilla Bug 990812"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    /* global messageManager, sendAsyncMessage, getGroupMessageManager */
+    var FRAME_SCRIPT_GLOBAL = "data:,sendSyncMessage('test', 'global')";
+    var FRAME_SCRIPT_WINDOW = "data:,sendSyncMessage('test', 'window')";
+    var FRAME_SCRIPT_GROUP  = "data:,sendSyncMessage('test', 'group')";
+
+    var globalMM = Cc["@mozilla.org/globalmessagemanager;1"].getService();
+
+    function is(val, exp, msg) {
+      window.arguments[0].is(val, exp, msg);
+    }
+
+    /**
+     * Ensures that delayed frame scripts are loaded in the expected order.
+     * Global frame scripts will be loaded before delayed frame scripts from
+     * window message managers. The latter will be loaded before group message
+     * manager frame scripts.
+     */
+    function start() {
+      globalMM.loadFrameScript(FRAME_SCRIPT_GLOBAL, true);
+      messageManager.loadFrameScript(FRAME_SCRIPT_WINDOW, true);
+      getGroupMessageManager("test").loadFrameScript(FRAME_SCRIPT_GROUP, true);
+
+      var order = ["global", "window", "group"];
+
+      messageManager.addMessageListener("test", function onMessage(msg) {
+        var next = order.shift();
+        window.arguments[0].is(msg.data, next, "received test:" + next);
+
+        if (!order.length) {
+          window.arguments[0].setTimeout(function() { this.next(); });
+          window.close();
+        }
+      });
+
+      var browser = document.createXULElement("browser");
+      browser.setAttribute("messagemanagergroup", "test");
+      browser.setAttribute("src", "about:mozilla");
+      browser.setAttribute("type", "content");
+      document.documentElement.appendChild(browser);
+
+      globalMM.removeDelayedFrameScript(FRAME_SCRIPT_GLOBAL);
+      messageManager.removeDelayedFrameScript(FRAME_SCRIPT_WINDOW);
+      getGroupMessageManager("test").removeDelayedFrameScript(FRAME_SCRIPT_GROUP);
+    }
+
+  ]]></script>
+
+</window>
diff --git a/dom/base/test/chrome/file_bug990812-2.xhtml b/dom/base/test/chrome/file_bug990812-2.xhtml
new file mode 100644
index 0000000000..e13b47f589
--- /dev/null
+++ b/dom/base/test/chrome/file_bug990812-2.xhtml
@@ -0,0 +1,56 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=990812
+-->
+<window title="Mozilla Bug 990812"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="start();">
+  <label value="Mozilla Bug 990812"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    /* global messageManager, sendAsyncMessage, getGroupMessageManager */
+    var FRAME_SCRIPT = "data:,sendAsyncMessage('test')";
+    var order = ["group", "window", "global"];
+
+    var globalMM = Cc["@mozilla.org/globalmessagemanager;1"].getService();
+
+    function is(val, exp, msg) {
+      window.arguments[0].is(val, exp, msg);
+    }
+
+    function promiseMessage(type, mm) {
+      return new Promise(function (resolve) {
+        mm.addMessageListener("test", function onMessage() {
+          mm.removeMessageListener("test", onMessage);
+          is(type, order.shift(), "correct type " + type);
+          resolve();
+        });
+      });
+    }
+
+    /**
+     * Tests that async messages sent by frame scripts bubble up as expected,
+     * passing the group, window, and global message managers in that order.
+     */
+    function start() {
+      var global = promiseMessage("global", globalMM);
+      var window = promiseMessage("window", messageManager);
+      var group = promiseMessage("group", getGroupMessageManager("test"));
+
+      var browser = document.querySelector("browser");
+      browser.messageManager.loadFrameScript(FRAME_SCRIPT, true);
+
+      Promise.all([global, window, group]).then(function () {
+        self.arguments[0].setTimeout(function() { this.next(); });
+        self.close();
+      });
+    }
+
+  ]]></script>
+
+  <browser messagemanagergroup="test" type="content" src="about:mozilla" />
+
+</window>
diff --git a/dom/base/test/chrome/file_bug990812-3.xhtml b/dom/base/test/chrome/file_bug990812-3.xhtml
new file mode 100644
index 0000000000..1f3e1d69f2
--- /dev/null
+++ b/dom/base/test/chrome/file_bug990812-3.xhtml
@@ -0,0 +1,68 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=990812
+-->
+<window title="Mozilla Bug 990812"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="start();">
+  <label value="Mozilla Bug 990812"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    /* global messageManager, sendAsyncMessage, getGroupMessageManager */
+    var FRAME_SCRIPT = "data:,addMessageListener('test', function (msg) {" +
+                       "sendSyncMessage('test', msg.data)})";
+
+    var globalMM = Cc["@mozilla.org/globalmessagemanager;1"].getService();
+
+    function is(val, exp, msg) {
+      window.arguments[0].is(val, exp, msg);
+    }
+
+    function promiseMessage(type, mm) {
+      var order = [type, "window", "global"];
+
+      return new Promise(function (resolve) {
+        mm.addMessageListener("test", function onMessage(msg) {
+          is(msg.data, order.shift(), "correct message " + msg.data);
+
+          if (!order.length) {
+            mm.removeMessageListener("test", onMessage);
+            resolve();
+          }
+        });
+      });
+    }
+
+    /**
+     * Ensures that broadcasting an async message does only reach descendants
+     * of a specific message manager and respects message manager groups.
+     */
+    function start() {
+      var mm1 = document.querySelector("browser").messageManager;
+      var promise1 = promiseMessage("group1", mm1);
+      mm1.loadFrameScript(FRAME_SCRIPT, true);
+
+      var mm2 = document.querySelector("browser + browser").messageManager;
+      var promise2 = promiseMessage("group2", mm2);
+      mm2.loadFrameScript(FRAME_SCRIPT, true);
+
+      getGroupMessageManager("test1").broadcastAsyncMessage("test", "group1");
+      getGroupMessageManager("test2").broadcastAsyncMessage("test", "group2");
+      messageManager.broadcastAsyncMessage("test", "window");
+      globalMM.broadcastAsyncMessage("test", "global");
+
+      Promise.all([promise1, promise2]).then(function () {
+        window.arguments[0].setTimeout(function() { this.next(); });
+        window.close();
+      });
+    }
+
+  ]]></script>
+
+  <browser messagemanagergroup="test1" type="content" src="about:mozilla" />
+  <browser messagemanagergroup="test2" type="content" src="about:mozilla" />
+
+</window>
diff --git a/dom/base/test/chrome/file_bug990812-4.xhtml b/dom/base/test/chrome/file_bug990812-4.xhtml
new file mode 100644
index 0000000000..1c16ceb02c
--- /dev/null
+++ b/dom/base/test/chrome/file_bug990812-4.xhtml
@@ -0,0 +1,63 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=990812
+-->
+<window title="Mozilla Bug 990812"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="start();">
+  <label value="Mozilla Bug 990812"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    /* global messageManager, sendAsyncMessage, getGroupMessageManager */
+    var FRAME_SCRIPT1 = "data:,addMessageListener('test', function () {" +
+                        "sendSyncMessage('test', 'frame1')})";
+    var FRAME_SCRIPT2 = "data:,addMessageListener('test', function () {" +
+                        "sendSyncMessage('test', 'frame2')})";
+
+    var globalMM = Cc["@mozilla.org/globalmessagemanager;1"].getService();
+
+    function is(val, exp, msg) {
+      window.arguments[0].is(val, exp, msg);
+    }
+
+    function promiseMessage(type, mm) {
+      return new Promise(function (resolve) {
+        mm.addMessageListener("test", function onMessage(msg) {
+          mm.removeMessageListener("test", onMessage);
+          is(msg.data, type, "correct message " + type);
+          resolve();
+        });
+      });
+    }
+
+    /**
+     * Tests that swapping docShells works as expected wrt to groups.
+     */
+    function start() {
+      var browser1 = document.querySelector("browser");
+      browser1.messageManager.loadFrameScript(FRAME_SCRIPT1, true);
+
+      var browser2 = document.querySelector("browser + browser");
+      browser2.messageManager.loadFrameScript(FRAME_SCRIPT2, true);
+
+      var promise1 = promiseMessage("frame2", getGroupMessageManager("test1"));
+      var promise2 = promiseMessage("frame1", getGroupMessageManager("test2"));
+
+      browser1.swapFrameLoaders(browser2);
+      messageManager.broadcastAsyncMessage("test");
+
+      Promise.all([promise1, promise2]).then(function () {
+        window.arguments[0].setTimeout(function() { this.next(); });
+        window.close();
+      });
+    }
+
+  ]]></script>
+
+  <browser messagemanagergroup="test1" type="content" src="about:mozilla" />
+  <browser messagemanagergroup="test2" type="content" src="about:mozilla" />
+
+</window>
diff --git a/dom/base/test/chrome/file_bug990812-5.xhtml b/dom/base/test/chrome/file_bug990812-5.xhtml
new file mode 100644
index 0000000000..8c418492a1
--- /dev/null
+++ b/dom/base/test/chrome/file_bug990812-5.xhtml
@@ -0,0 +1,74 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=990812
+-->
+<window title="Mozilla Bug 990812"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="start();">
+  <label value="Mozilla Bug 990812"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    /* global messageManager, sendAsyncMessage, getGroupMessageManager */
+    var FRAME_SCRIPT1 = "data:,addMessageListener('test', function () {" +
+                        "sendSyncMessage('test', 'group1')})";
+    var FRAME_SCRIPT2 = "data:,addMessageListener('test', function () {" +
+                        "sendSyncMessage('test', 'group2')})";
+
+    var globalMM = Cc["@mozilla.org/globalmessagemanager;1"].getService();
+
+    function is(val, exp, msg) {
+      window.arguments[0].is(val, exp, msg);
+    }
+
+    function promiseTwoMessages(type, mm) {
+      var numLeft = 2;
+
+      return new Promise(function (resolve) {
+        mm.addMessageListener("test", function onMessage(msg) {
+          is(msg.data, type, "correct message " + type);
+
+          if (--numLeft == 0) {
+            mm.removeMessageListener("test", onMessage);
+            resolve();
+          }
+        });
+      });
+    }
+
+    /**
+     * This test ensures that having multiple message manager groups with
+     * multiple frame loaders in those works as expected. For a specific
+     * group message manager, frame scripts should only be loaded by its
+     * descendants and messages should only be received by and from those
+     * child message managers.
+     */
+    function start() {
+      var gmm1 = getGroupMessageManager("test1");
+      gmm1.loadFrameScript(FRAME_SCRIPT1, true);
+
+      var gmm2 = getGroupMessageManager("test2");
+      gmm2.loadFrameScript(FRAME_SCRIPT2, true);
+
+      var promise1 = promiseTwoMessages("group1", gmm1);
+      var promise2 = promiseTwoMessages("group2", gmm2);
+
+      messageManager.broadcastAsyncMessage("test");
+
+      Promise.all([promise1, promise2]).then(function () {
+        window.arguments[0].setTimeout(function() { this.next(); });
+        window.close();
+      });
+    }
+
+  ]]></script>
+
+  <browser messagemanagergroup="test1" type="content" src="about:mozilla" />
+  <browser messagemanagergroup="test1" type="content" src="about:mozilla" />
+
+  <browser messagemanagergroup="test2" type="content" src="about:mozilla" />
+  <browser messagemanagergroup="test2" type="content" src="about:mozilla" />
+
+</window>
diff --git a/dom/base/test/chrome/file_bug990812.xhtml b/dom/base/test/chrome/file_bug990812.xhtml
new file mode 100644
index 0000000000..02662d5749
--- /dev/null
+++ b/dom/base/test/chrome/file_bug990812.xhtml
@@ -0,0 +1,55 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=990812
+-->
+<window title="Mozilla Bug 990812"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onload="start();">
+  <label value="Mozilla Bug 990812"/>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    /* global messageManager, sendAsyncMessage, getGroupMessageManager */
+    var FRAME_SCRIPT_GLOBAL = "data:,sendSyncMessage('test', 'global')";
+    var FRAME_SCRIPT_WINDOW = "data:,sendSyncMessage('test', 'window')";
+    var FRAME_SCRIPT_GROUP  = "data:,sendSyncMessage('test', 'group')";
+
+    var globalMM = Cc["@mozilla.org/globalmessagemanager;1"].getService();
+
+    function is(val, exp, msg) {
+      opener.wrappedJSObject.is(val, exp, msg);
+    }
+
+    function start() {
+      globalMM.loadFrameScript(FRAME_SCRIPT_GLOBAL, true);
+      messageManager.loadFrameScript(FRAME_SCRIPT_WINDOW, true);
+      getGroupMessageManager("test").loadFrameScript(FRAME_SCRIPT_GROUP, true);
+
+      var order = ["global", "window", "group"];
+
+      messageManager.addMessageListener("test", function onMessage(msg) {
+        var next = order.shift();
+        opener.wrappedJSObject.is(msg.data, next, "received test:" + next);
+
+        if (!order.length) {
+          opener.setTimeout("next()");
+          window.close();
+        }
+      });
+
+      var browser = document.createXULElement("browser");
+      browser.setAttribute("messagemanagergroup", "test");
+      browser.setAttribute("src", "about:mozilla");
+      browser.setAttribute("type", "content");
+      document.documentElement.appendChild(browser);
+
+      globalMM.removeDelayedFrameScript(FRAME_SCRIPT_GLOBAL);
+      messageManager.removeDelayedFrameScript(FRAME_SCRIPT_WINDOW);
+      getGroupMessageManager("test").removeDelayedFrameScript(FRAME_SCRIPT_GROUP);
+    }
+
+  ]]></script>
+
+</window>
diff --git a/dom/base/test/chrome/file_document-element-inserted-inner.xhtml b/dom/base/test/chrome/file_document-element-inserted-inner.xhtml
new file mode 100644
index 0000000000..2088e2789a
--- /dev/null
+++ b/dom/base/test/chrome/file_document-element-inserted-inner.xhtml
@@ -0,0 +1 @@
+<window xmlns='http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul'></window>
\ No newline at end of file
diff --git a/dom/base/test/chrome/file_document-element-inserted.xhtml b/dom/base/test/chrome/file_document-element-inserted.xhtml
new file mode 100644
index 0000000000..d67df13df7
--- /dev/null
+++ b/dom/base/test/chrome/file_document-element-inserted.xhtml
@@ -0,0 +1,3 @@
+<window xmlns='http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul'>
+  <iframe src='file_document-element-inserted-inner.xhtml'></iframe>
+</window>
\ No newline at end of file
diff --git a/dom/base/test/chrome/file_title.xhtml b/dom/base/test/chrome/file_title.xhtml
new file mode 100644
index 0000000000..d1b04418aa
--- /dev/null
+++ b/dom/base/test/chrome/file_title.xhtml
@@ -0,0 +1 @@
+<window xmlns='http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul' title='Test'/>
diff --git a/dom/base/test/chrome/fileconstructor_file.png b/dom/base/test/chrome/fileconstructor_file.png
new file mode 100644
index 0000000000..51e8aaf38c
--- /dev/null
+++ b/dom/base/test/chrome/fileconstructor_file.png
diff --git a/dom/base/test/chrome/frame_custom_element_content.html b/dom/base/test/chrome/frame_custom_element_content.html
new file mode 100644
index 0000000000..aa1d75863d
--- /dev/null
+++ b/dom/base/test/chrome/frame_custom_element_content.html
@@ -0,0 +1,5 @@
+<html>
+<body>
+<x-bar></x-bar>
+</body>
+</html>
diff --git a/dom/base/test/chrome/nochrome_bug1346936.html b/dom/base/test/chrome/nochrome_bug1346936.html
new file mode 100644
index 0000000000..158b20c884
--- /dev/null
+++ b/dom/base/test/chrome/nochrome_bug1346936.html
@@ -0,0 +1,3 @@
+<!DOCTYPE HTML>
+<html>
+</html>
diff --git a/dom/base/test/chrome/nochrome_bug1346936.js b/dom/base/test/chrome/nochrome_bug1346936.js
new file mode 100644
index 0000000000..a84113e1e1
--- /dev/null
+++ b/dom/base/test/chrome/nochrome_bug1346936.js
@@ -0,0 +1,4 @@
+//# sourceMappingURL=bar.js.map
+
+// Define a single function to prevent script source from being gc'd
+function foo() {}
diff --git a/dom/base/test/chrome/nochrome_bug1346936.js^headers^ b/dom/base/test/chrome/nochrome_bug1346936.js^headers^
new file mode 100644
index 0000000000..812264590d
--- /dev/null
+++ b/dom/base/test/chrome/nochrome_bug1346936.js^headers^
@@ -0,0 +1 @@
+SourceMap: foo.js.map
diff --git a/dom/base/test/chrome/nochrome_bug765993.html b/dom/base/test/chrome/nochrome_bug765993.html
new file mode 100644
index 0000000000..158b20c884
--- /dev/null
+++ b/dom/base/test/chrome/nochrome_bug765993.html
@@ -0,0 +1,3 @@
+<!DOCTYPE HTML>
+<html>
+</html>
diff --git a/dom/base/test/chrome/nochrome_bug765993.js b/dom/base/test/chrome/nochrome_bug765993.js
new file mode 100644
index 0000000000..a84113e1e1
--- /dev/null
+++ b/dom/base/test/chrome/nochrome_bug765993.js
@@ -0,0 +1,4 @@
+//# sourceMappingURL=bar.js.map
+
+// Define a single function to prevent script source from being gc'd
+function foo() {}
diff --git a/dom/base/test/chrome/nochrome_bug765993.js^headers^ b/dom/base/test/chrome/nochrome_bug765993.js^headers^
new file mode 100644
index 0000000000..8efacff3c8
--- /dev/null
+++ b/dom/base/test/chrome/nochrome_bug765993.js^headers^
@@ -0,0 +1 @@
+X-SourceMap: foo.js.map
diff --git a/dom/base/test/chrome/test_bug1063837.xhtml b/dom/base/test/chrome/test_bug1063837.xhtml
new file mode 100644
index 0000000000..794cf1c72c
--- /dev/null
+++ b/dom/base/test/chrome/test_bug1063837.xhtml
@@ -0,0 +1,36 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=206691
+-->
+<window title="Mozilla Bug 1063837"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1063837"
+     target="_blank">Mozilla Bug 1063837</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+  /** Test for Bug 1063837 **/
+  SimpleTest.waitForExplicitFinish();
+
+  addLoadEvent(function() {
+    var xhr = new XMLHttpRequest();
+    xhr.open("GET", location, false);
+    xhr.onload = function() {
+      ok(xhr.responseXML, "We should have response content!");
+      var principal = xhr.responseXML.nodePrincipal;
+      ok(principal.schemeIs("moz-nullprincipal"), "The response document should have a null principal");
+      SimpleTest.finish();
+    }
+    xhr.send();
+  });
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug1098074_throw_from_ReceiveMessage.xhtml b/dom/base/test/chrome/test_bug1098074_throw_from_ReceiveMessage.xhtml
new file mode 100644
index 0000000000..769c10b370
--- /dev/null
+++ b/dom/base/test/chrome/test_bug1098074_throw_from_ReceiveMessage.xhtml
@@ -0,0 +1,47 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1098074
+-->
+<window title="Mozilla Bug 1098074"
+    xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+    onload="start();">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+  /** Test for Bug 1098074 **/
+  SimpleTest.waitForExplicitFinish();
+  SimpleTest.expectUncaughtException();
+
+  // Tell the test to expect exactly one console error with the given parameters,
+  // with SimpleTest.finish as a continuation function.
+  SimpleTest.monitorConsole(SimpleTest.finish, [{errorMessage: new RegExp('acopia')}]);
+
+  var globalMM = Cc["@mozilla.org/globalmessagemanager;1"].getService();
+  globalMM.addMessageListener("flimfniffle", function onMessage(msg) {
+    globalMM.removeMessageListener("flimfniffle", onMessage);
+    is(msg.data, "teufeltor", "correct message");
+
+    // Cleanup the monitor after we throw.
+    SimpleTest.executeSoon(SimpleTest.endMonitorConsole);
+
+    // eslint-disable-next-line no-throw-literal
+    throw "acopia";
+  });
+
+  function start() {
+    globalMM.loadFrameScript("data:,sendAsyncMessage('flimfniffle', 'teufeltor')", true);
+  }
+
+  ]]>
+  </script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1098074"
+     target="_blank">Mozilla Bug 1098074</a>
+  </body>
+</window>
diff --git a/dom/base/test/chrome/test_bug1139964.xhtml b/dom/base/test/chrome/test_bug1139964.xhtml
new file mode 100644
index 0000000000..8b1b36fa64
--- /dev/null
+++ b/dom/base/test/chrome/test_bug1139964.xhtml
@@ -0,0 +1,32 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1139964
+-->
+<window title="Mozilla Bug 1139964"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1139964"
+     target="_blank">Mozilla Bug 1139964</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+  /** Test for Bug 1139964 **/
+  SimpleTest.waitForExplicitFinish();
+
+  function done() {
+    SimpleTest.finish();
+  }
+
+  addLoadEvent(function() {
+    window.openDialog("file_bug1139964.xhtml", "", "chrome,noopener", window);
+  });
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug120684.xhtml b/dom/base/test/chrome/test_bug120684.xhtml
new file mode 100644
index 0000000000..08e9b28cfe
--- /dev/null
+++ b/dom/base/test/chrome/test_bug120684.xhtml
@@ -0,0 +1,80 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=120684
+-->
+<window title="Mozilla Bug 120684"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=120684"
+     target="_blank">Mozilla Bug 120684</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+  /** Test for Bug 120684 **/
+
+  var list = new ChromeNodeList();
+  is(list.length, 0, "Length should be initially 0.");
+
+  ok(NodeList.isInstance(list), "ChromeNodeList object should be an instance of NodeList.");
+
+  try {
+    list.append(document);
+    ok(false, "should have throw!");
+  } catch(ex) {
+    ok(true, "ChromeNodeList supports only nsIContent objects for now.");
+  }
+
+  try {
+    list.remove(document);
+    ok(false, "should have throw!");
+  } catch(ex) {
+    ok(true, "ChromeNodeList supports only nsIContent objects for now.");
+  }
+  is(list.length, 0, "Length should be 0.");
+
+  list.append(document.documentElement);
+  is(list.length, 1, "Length should be 1.");
+  is(list[0], document.documentElement);
+  is(list[1], undefined);
+
+  // Removing element which isn't in the list shouldn't do anything.
+  list.remove(document.createXULElement("foo"));
+  is(list.length, 1, "Length should be 1.");
+  is(list[0], document.documentElement);
+
+  list.remove(document.documentElement);
+  is(list.length, 0, "Length should be 0.");
+  is(list[0], undefined);
+
+  var e1 = document.createXULElement("foo");
+  var e2 = document.createXULElement("foo");
+  var e3 = document.createXULElement("foo");
+
+  list.append(e1);
+  list.append(e2);
+  list.append(e3);
+
+  is(list[0], e1);
+  is(list[1], e2);
+  is(list[2], e3);
+  is(list.length, 3);
+
+  list.remove(e2);
+  is(list[0], e1);
+  is(list[1], e3);
+  is(list[2], undefined);
+  is(list.length, 2);
+
+  // A leak test.
+  list.expando = list;
+
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_bug1209621.xhtml b/dom/base/test/chrome/test_bug1209621.xhtml
new file mode 100644
index 0000000000..947606b638
--- /dev/null
+++ b/dom/base/test/chrome/test_bug1209621.xhtml
@@ -0,0 +1,34 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1209621
+-->
+<window title="Mozilla Bug 1209621"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1209621"
+     target="_blank">Mozilla Bug 1209621</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+  /** Test for Bug 1209621 **/
+
+  SimpleTest.waitForExplicitFinish();
+
+  function done() {
+    SimpleTest.finish();
+  }
+
+  addLoadEvent(function() {
+    window.openDialog("file_bug1209621.xhtml", "", "chrome,noopener", window);
+  });
+
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_bug1339722.html b/dom/base/test/chrome/test_bug1339722.html
new file mode 100644
index 0000000000..d8d95f1faa
--- /dev/null
+++ b/dom/base/test/chrome/test_bug1339722.html
@@ -0,0 +1,86 @@
+<!DOCTYPE html>
+<html>
+  <!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1339722
+-->
+  <head>
+    <meta charset="utf-8" />
+    <title>Test for Bug 1339722</title>
+    <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+    <link rel="stylesheet" type="text/css" href="chrome://global/skin" />
+    <link
+      rel="stylesheet"
+      type="text/css"
+      href="chrome://mochikit/content/tests/SimpleTest/test.css"
+    />
+    <script type="application/javascript">
+      /**
+       * Test for Bug 1339722
+       * 1. Wait for "http-on-modify-request" or document-on-modify-request for the
+       *    iframe load.
+       * 2. In the observer, access it's window proxy to trigger DOMWindowCreated.
+       * 3. In the event handler, delete the iframe so that the frameloader would be
+       *    destroyed in the middle of ReallyStartLoading.
+       * 4. Verify that it doesn't crash.
+       **/
+
+      // This topic used to be http-on-useragent-request, but that got removed in
+      // bug 1513574. on-modify-request is called around the same time, and should
+      // behave similarly.
+      const TOPIC = "document-on-modify-request";
+      let win;
+      const observe = (subject, topic, data) => {
+        info("Got " + topic);
+        Services.obs.removeObserver(observe, TOPIC);
+
+        // Query window proxy so it triggers DOMWindowCreated.
+        let channel;
+        try {
+          // We need to QI nsIHttpChannel in order to load the interface's
+          // methods / attributes for later code that could assume we are dealing
+          // with a nsIHttpChannel.
+          channel = subject.QueryInterface(Ci.nsIHttpChannel);
+        } catch (e) {
+          channel = subject.QueryInterface(Ci.nsIIdentChannel);
+        }
+        win = channel.notificationCallbacks.getInterface(Ci.mozIDOMWindowProxy);
+      };
+
+      Services.obs.addObserver(observe, TOPIC);
+
+      let docShell = SpecialPowers.wrap(window).docShell;
+      docShell.chromeEventHandler.addEventListener(
+        "DOMWindowCreated",
+        function handler(e) {
+          info("Got DOMWindowCreated");
+          let iframe = document.getElementById("testFrame");
+          is(e.target, iframe.contentDocument, "verify event target");
+
+          // Remove the iframe to cause frameloader destroy.
+          iframe.remove();
+          setTimeout($ => {
+            ok(!document.getElementById("testFrame"), "verify iframe removed");
+            SimpleTest.finish();
+          }, 0);
+        },
+        { once: true }
+      );
+
+      SimpleTest.waitForExplicitFinish();
+    </script>
+  </head>
+  <body>
+    <a
+      target="_blank"
+      href="https://bugzilla.mozilla.org/show_bug.cgi?id=1339722"
+      >Mozilla Bug 1339722</a
+    >
+    <p id="display"></p>
+    <div id="content" style="display: none;"></div>
+    <pre id="test">
+  <div id="frameContainer">
+    <iframe id="testFrame" src="http://www.example.com"></iframe>
+  </div>
+</pre>
+  </body>
+</html>
diff --git a/dom/base/test/chrome/test_bug1346936.html b/dom/base/test/chrome/test_bug1346936.html
new file mode 100644
index 0000000000..2c61c65237
--- /dev/null
+++ b/dom/base/test/chrome/test_bug1346936.html
@@ -0,0 +1,61 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1346936
+-->
+<head>
+  <title>Test for Bug 1346936</title>
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="application/javascript"  src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1346936">Mozilla Bug 1346936</a>
+<style type="text/css">
+#link1 a { user-select:none; }
+</style>
+<div id="link1"><a href="http://www.mozilla.org/">link1</a></div>
+<div id="link2"><a href="http://www.mozilla.org/">link2</a></div>
+<p id="display"></p>
+<div id="content" style="display: none">
+  
+</div>
+<pre id="test">
+<script type="application/javascript">
+
+/** Test for Bug 1346936 **/
+
+const {addDebuggerToGlobal} = ChromeUtils.importESModule("resource://gre/modules/jsdebugger.sys.mjs");
+addDebuggerToGlobal(globalThis);
+
+window.onload = function() {
+    SimpleTest.waitForExplicitFinish();
+
+    var iframe = document.createElement("iframe");
+    iframe.src = "http://mochi.test:8888/tests/dom/base/test/chrome/nochrome_bug1346936.html";
+    iframe.onload = function() {
+        var script = iframe.contentWindow.document.createElement("script");
+        script.src = "http://mochi.test:8888/tests/dom/base/test/chrome/nochrome_bug1346936.js";
+        script.onload = function() {
+            var dbg = new Debugger(iframe.contentWindow);
+            ok(dbg, "Should be able to create debugger");
+
+            var scripts = dbg.findScripts({
+                url: "http://mochi.test:8888/tests/dom/base/test/chrome/nochrome_bug1346936.js",
+            });
+            ok(scripts.length, "Should be able to find script");
+
+            is(scripts[0].source.sourceMapURL, "foo.js.map");
+            SimpleTest.finish();
+        };
+
+        iframe.contentWindow.document.body.appendChild(script);
+    };
+
+    document.body.appendChild(iframe);
+};
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/dom/base/test/chrome/test_bug206691.xhtml b/dom/base/test/chrome/test_bug206691.xhtml
new file mode 100644
index 0000000000..16a27762ac
--- /dev/null
+++ b/dom/base/test/chrome/test_bug206691.xhtml
@@ -0,0 +1,32 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=206691
+-->
+<window title="Mozilla Bug 206691"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=206691"
+     target="_blank">Mozilla Bug 206691</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+  /** Test for Bug 206691 **/
+  SimpleTest.waitForExplicitFinish();
+
+  addLoadEvent(function() {
+    var xhr = new XMLHttpRequest();
+    xhr.open("GET", location, false);
+    xhr.send();
+    ok(xhr.responseText, "We should have response content!");
+    SimpleTest.finish();
+  });
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug289714.xhtml b/dom/base/test/chrome/test_bug289714.xhtml
new file mode 100644
index 0000000000..4b4cc6fb84
--- /dev/null
+++ b/dom/base/test/chrome/test_bug289714.xhtml
@@ -0,0 +1,33 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=289714
+-->
+<window title="Mozilla Bug 289714"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=289714"
+     target="_blank">Mozilla Bug 289714</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+  /** Test for Bug 289714 **/
+
+  SimpleTest.waitForExplicitFinish();
+
+  let xhr = new XMLHttpRequest();
+  xhr.responseType = "document";
+  xhr.open("GET", "data:text/xml,<xml");
+  ok(xhr.channel !== undefined, "System XHRs should be privileged");
+  xhr.onload = () => {
+    ok(xhr.responseXML !== null, "System XHRs should yield <parsererrors>");
+    SimpleTest.finish();
+  };
+  xhr.send();
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug339494.xhtml b/dom/base/test/chrome/test_bug339494.xhtml
new file mode 100644
index 0000000000..203f6e644d
--- /dev/null
+++ b/dom/base/test/chrome/test_bug339494.xhtml
@@ -0,0 +1,73 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=339494
+-->
+<window title="Mozilla Bug 339494"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+<body  xmlns="http://www.w3.org/1999/xhtml">
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=339494">Mozilla Bug 339494</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+  <xul:hbox id="d"/>
+  <xul:hbox id="s"/>
+</div>
+<pre id="test">
+</pre>
+</body>
+
+<script class="testbody" type="application/javascript">
+
+/** Test for Bug 339494 **/
+SimpleTest.waitForExplicitFinish();
+
+(async function runTests() {
+  function promiseFlushingMutationObserver() {
+    return new Promise(SimpleTest.executeSoon);
+  }
+
+  await (async function() {
+    const d = document.getElementById("d");
+
+    d.setAttribute("hhh", "testvalue");
+    await promiseFlushingMutationObserver();
+
+    const observer = new MutationObserver((aMutationList, aObserver) => {
+      ok(!d.hasAttribute("hhh"), "Value check 1. There should be no value");
+      isnot(d.getAttribute("hhh"), "testvalue", "Value check 2");
+      aObserver.disconnect();
+      d.removeAttribute("hhh");
+      ok(true, "Reachability. We shouldn't have crashed");
+    });
+    observer.observe(d, { attributes: true });
+    d.removeAttribute("hhh");
+    await promiseFlushingMutationObserver();
+  })();
+
+  await (async function() {
+    const s = document.getElementById("s");
+
+    s.setAttribute("ggg", "testvalue");
+    await promiseFlushingMutationObserver();
+
+    const observer = new MutationObserver((aMutationList, aObserver) => {
+      ok(s.hasAttribute("ggg"), "Value check 3. There should be a value");
+      isnot(s.getAttribute("ggg"), "testvalue", "Value check 4");
+      is(s.getAttribute("ggg"), "othervalue", "Value check 5");
+    });
+    observer.observe(s, { attributes: true });
+    s.setAttribute("ggg", "othervalue");
+    await promiseFlushingMutationObserver();
+    observer.disconnect();
+  })();
+
+  SimpleTest.finish();
+})();
+</script>
+
+</window>
diff --git a/dom/base/test/chrome/test_bug357450.xhtml b/dom/base/test/chrome/test_bug357450.xhtml
new file mode 100644
index 0000000000..7723364ecc
--- /dev/null
+++ b/dom/base/test/chrome/test_bug357450.xhtml
@@ -0,0 +1,56 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>
+
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=357450
+-->
+
+<window title="Mozilla Bug 357450"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+
+  <script type="application/javascript" 
+	  src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>      
+  <!-- This file is shared with non-chrome tests -->
+  <script type="text/javascript" src="file_bug357450.js"></script>
+
+<body  xmlns="http://www.w3.org/1999/xhtml">
+
+<a href="https://bugzilla.mozilla.org/show_bug.cgi?id=357450"
+   target="_blank">Mozilla Bug 357450</a>
+
+<p id="display"></p>
+
+<div id="content" style="display: block">
+  <a class="classtest" name="nametest">hmm</a>
+  <b class="foo">hmm</b>
+  <b id="test1" class="test1">hmm</b>
+  <b id="test2" class="test2">hmm</b>
+  <b id="int-class" class="1">hmm</b>
+  <div id="example">
+   <p id="p1" class="aaa bbb"/>
+   <p id="p2" class="aaa ccc"/>
+   <p id="p3" class="bbb ccc"/>
+  </div>
+</div>
+<pre id="test">
+</pre>
+</body>
+
+<svg xmlns="http://www.w3.org/2000/svg"
+     height="100" width="100" style="float:left">
+
+  <path d="M38,38c0-12,24-15,23-2c0,9-16,13-16,23v7h11v-4c0-9,17-12,17-27c-2-22-45-22-45,3zM45,70h11v11h-11z" fill="#371"/>
+
+  <circle cx="50" cy="50" r="45" class="classtest" 
+	  fill="none" stroke="#371" stroke-width="10"/>
+
+</svg>
+
+<xul:label class="classtest"
+ xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+ hmm
+</xul:label>
+
+
+</window>
diff --git a/dom/base/test/chrome/test_bug380418.html b/dom/base/test/chrome/test_bug380418.html
new file mode 100644
index 0000000000..eb3f8d3042
--- /dev/null
+++ b/dom/base/test/chrome/test_bug380418.html
@@ -0,0 +1,37 @@
+<!DOCTYPE HTML>
+<html>
+<!-- https://bugzilla.mozilla.org/show_bug.cgi?id=380418 -->
+<head>
+  <title>Test for Bug 380418</title>
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css" />
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=380418">Mozilla Bug 380418</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+  var xhrPath = "http://mochi.test:8888" +
+                window.location.pathname.substring("/content".length);
+
+  var request = new XMLHttpRequest();
+  request.open("GET", xhrPath, false);
+  request.send(null);
+
+  // Try reading headers in privileged context
+  is(request.getResponseHeader("Set-Cookie"), "test", "Reading Set-Cookie response header in privileged context");
+  is(request.getResponseHeader("Set-Cookie2"), "test2", "Reading Set-Cookie2 response header in privileged context");
+  is(request.getResponseHeader("X-Dummy"), "test", "Reading X-Dummy response header in privileged context");
+
+  ok(/\bSet-Cookie:/i.test(request.getAllResponseHeaders()), "Looking for Set-Cookie in all response headers in privileged context");
+  ok(/\bSet-Cookie2:/i.test(request.getAllResponseHeaders()), "Looking for Set-Cookie2 in all response headers in privileged context");
+  ok(/\bX-Dummy:/i.test(request.getAllResponseHeaders()), "Looking for X-Dummy in all response headers in privileged context");
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/dom/base/test/chrome/test_bug380418.html^headers^ b/dom/base/test/chrome/test_bug380418.html^headers^
new file mode 100644
index 0000000000..5f8d4969c0
--- /dev/null
+++ b/dom/base/test/chrome/test_bug380418.html^headers^
@@ -0,0 +1,4 @@
+Set-Cookie: test
+Set-Cookie2: test2
+X-Dummy: test
+Cache-Control: max-age=0
diff --git a/dom/base/test/chrome/test_bug383430.html b/dom/base/test/chrome/test_bug383430.html
new file mode 100644
index 0000000000..ce526ef281
--- /dev/null
+++ b/dom/base/test/chrome/test_bug383430.html
@@ -0,0 +1,38 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=383430
+-->
+<head>
+  <title>Test for Bug 383430</title>
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css" />
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=383430">Mozilla Bug 383430</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+  
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Bug 383430 **/
+
+var req = new XMLHttpRequest();
+req.open("GET", window.location.href);
+req.send(null);
+
+ok(req.channel.loadGroup != null, "loadGroup is not null");
+
+req = new XMLHttpRequest();
+req.mozBackgroundRequest = true;
+req.open("GET", window.location.href);
+req.send(null);
+
+ok(req.channel.loadGroup == null, "loadGroup is null");
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/dom/base/test/chrome/test_bug418986-1.xhtml b/dom/base/test/chrome/test_bug418986-1.xhtml
new file mode 100644
index 0000000000..7d3add900a
--- /dev/null
+++ b/dom/base/test/chrome/test_bug418986-1.xhtml
@@ -0,0 +1,25 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=418986-1
+-->
+<window title="Mozilla Bug 418986 (Part 1)"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=418986-1"
+     target="_blank">Mozilla Bug 418986 (Part 1)</a>
+
+  <script type="application/javascript" src="bug418986-1.js"></script>
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    window.onload = function() {
+      test(false);
+    };
+  ]]></script>
+  </body>
+</window>
diff --git a/dom/base/test/chrome/test_bug421622.xhtml b/dom/base/test/chrome/test_bug421622.xhtml
new file mode 100644
index 0000000000..236c42dd34
--- /dev/null
+++ b/dom/base/test/chrome/test_bug421622.xhtml
@@ -0,0 +1,34 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=421622
+-->
+<window title="Mozilla Bug 421622"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=421622"
+     target="_blank">Mozilla Bug 421622</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+    /** Test for Bug 421622 **/
+    const SJS_URL = "http://mochi.test:8888/tests/dom/base/test/chrome/bug421622-referer.sjs";
+    const REFERER_URL = "http://www.mozilla.org/";
+
+    var req = new XMLHttpRequest();
+    req.open("GET", SJS_URL, false);
+    req.setRequestHeader("Referer", REFERER_URL);
+    req.send(null);
+
+    is(req.responseText,
+       "Referer: " + REFERER_URL,
+       "Referer header received by server does not match what was set");
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug429785.xhtml b/dom/base/test/chrome/test_bug429785.xhtml
new file mode 100644
index 0000000000..fb51634fab
--- /dev/null
+++ b/dom/base/test/chrome/test_bug429785.xhtml
@@ -0,0 +1,53 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=429785
+-->
+<window title="Mozilla Bug 429785"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=429785"
+     target="_blank">Mozilla Bug 429785</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    /** Test for Bug 429785 **/
+    SimpleTest.waitForExplicitFinish();
+    var errorLogged = false;
+    var listener = {
+      QueryInterface: ChromeUtils.generateQI(["nsIConsoleListener"]),
+      observe(msg) { errorLogged = true; }
+    };
+
+    function step2() {
+      is(errorLogged, false, "Should be no errors");
+
+      Services.console.logStringMessage("This is a test");
+
+      setTimeout(step3, 0);
+
+    }
+
+    function step3() {
+      is(errorLogged, true, "Should see errors when they happen");
+      Services.console.unregisterListener(listener);
+      SimpleTest.finish();
+    }
+        
+    Services.console.registerListener(listener);
+
+    var p = new DOMParser();
+    p.parseFromString("<root/>", "application/xml");
+
+    // nsConsoleService notifies its listeners via async proxies, so we need
+    // to wait to see whether there was an error reported.
+    setTimeout(step2, 0);
+
+
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug430050.xhtml b/dom/base/test/chrome/test_bug430050.xhtml
new file mode 100644
index 0000000000..d7d6cf656c
--- /dev/null
+++ b/dom/base/test/chrome/test_bug430050.xhtml
@@ -0,0 +1,48 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=430050
+-->
+<window title="Mozilla Bug 430050"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=430050"
+     target="_blank">Mozilla Bug 430050</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+  /** Test for Bug 430050 **/
+
+  function endTest() {
+    ok(document.getElementById('b').contentDocument.documentElement.textContent ==
+       "succeeded", "Wrong URL loaded!");
+    SimpleTest.finish();
+  }
+
+  function startTest() {
+    const observer = new MutationObserver((aMutationList, aObserver) => {
+      document.getElementById('b').setAttribute("src",
+                                                "data:text/plain,failed");
+      const systemPrincipal = Services.scriptSecurityManager.getSystemPrincipal();
+      document.getElementById('b').loadURI(Services.io.newURI('data:text/plain,succeeded'), {
+        triggeringPrincipal: systemPrincipal
+      });
+      document.getElementById('b').addEventListener("load", endTest);
+    });
+    observer.observe(document.documentElement, { attributes: true });
+    document.documentElement.setAttribute("foo", "bar");
+  }
+
+  SimpleTest.waitForExplicitFinish();
+  addLoadEvent(startTest);
+
+  ]]></script>
+  <browser flex="1" id="b"/>
+</window>
diff --git a/dom/base/test/chrome/test_bug467123.xhtml b/dom/base/test/chrome/test_bug467123.xhtml
new file mode 100644
index 0000000000..0811aba051
--- /dev/null
+++ b/dom/base/test/chrome/test_bug467123.xhtml
@@ -0,0 +1,42 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=467123
+-->
+<window title="Mozilla Bug 467123"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=467123"
+     target="_blank">Mozilla Bug 467123</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    /** Test for Bug 467123 **/
+    let url = Services.io.newURI(document.location.href);
+    let file = Cc["@mozilla.org/chrome/chrome-registry;1"]
+                 .getService(Ci.nsIChromeRegistry)
+                 .convertChromeURL(url)
+                 .QueryInterface(Ci.nsIFileURL)
+                 .file.parent;
+    file.append("clonedoc");
+    Components.manager.addBootstrappedManifestLocation(file);
+
+    var xhr = new XMLHttpRequest();
+    xhr.open("GET", "chrome://clonedoc/content/doc.xml", false);
+    xhr.send();
+    ok(xhr.responseXML, "We should have response document!");
+    var e = null;
+    try {
+      var clone = xhr.responseXML.cloneNode(true);
+    } catch (ex) {
+      e = ex;
+    }
+    ok(!e, e);
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug473284.xhtml b/dom/base/test/chrome/test_bug473284.xhtml
new file mode 100644
index 0000000000..87c778a615
--- /dev/null
+++ b/dom/base/test/chrome/test_bug473284.xhtml
@@ -0,0 +1,83 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=473284
+-->
+<window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+onload="
+var result = '';
+try {
+  document.commandDispatcher.advanceFocusIntoSubtree({});
+  result += '1';
+} catch (ex) {
+  result += '.';
+}
+
+try {
+  document.commandDispatcher.advanceFocusIntoSubtree(document.documentElement);
+  result += '2';
+} catch (ex) {
+  result += '.';
+}
+
+try {
+  document.commandDispatcher.advanceFocusIntoSubtree(null);
+  result += '3';
+} catch (ex) {
+  result += '.';
+}
+
+try {
+  document.commandDispatcher.focusedElement = {};
+  result += '4';
+} catch (ex) {
+  result += '.';
+}
+
+try {
+  document.commandDispatcher.focusedElement = document.documentElement;
+  result += '5';
+} catch (ex) {
+  result += '.';
+}
+
+try {
+  document.commandDispatcher.focusedElement = null;
+  result += '6';
+} catch (ex) {
+  result += '.';
+}
+
+try {
+  document.commandDispatcher.focusedWindow = {};
+  result += 'a';
+} catch (ex) {
+  result += '.';
+}
+
+try {
+  document.commandDispatcher.focusedWindow = null;
+  result += 'b';
+} catch (ex) {
+  result += '.';
+}
+
+try {
+  document.commandDispatcher.focusedWindow = window;
+  result += 'c';
+} catch (ex) {
+  result += '.';
+}
+
+is(result, '.23.56.bc', 'The correct assignments throw.');
+">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=473284"
+     target="_blank">Mozilla Bug 473284</a>
+  </body>
+</window>
diff --git a/dom/base/test/chrome/test_bug549682.xhtml b/dom/base/test/chrome/test_bug549682.xhtml
new file mode 100644
index 0000000000..0f1ecf646a
--- /dev/null
+++ b/dom/base/test/chrome/test_bug549682.xhtml
@@ -0,0 +1,32 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=549682
+-->
+<window title="Mozilla Bug 549682"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=549682"
+     target="_blank">Mozilla Bug 549682</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+  /** Test for Bug 549682 **/
+  SimpleTest.waitForExplicitFinish();
+
+  function done() {
+    SimpleTest.finish();
+  }
+
+  addLoadEvent(function() {
+    window.openDialog("file_bug549682.xhtml", "", "chrome,noopener", window);
+  });
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug571390.xhtml b/dom/base/test/chrome/test_bug571390.xhtml
new file mode 100644
index 0000000000..ea1f357a5d
--- /dev/null
+++ b/dom/base/test/chrome/test_bug571390.xhtml
@@ -0,0 +1,42 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=571390
+-->
+<window title="Mozilla Bug 571390"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        class="foo bar">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=571390"
+     target="_blank">Mozilla Bug 571390</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+
+  /** Test for Bug 571390 **/
+
+  is(document.documentElement.classList.length, 2, "Should have 2 classes.");
+  ok(document.documentElement.classList.contains("foo"), "Should contain 'foo' class.");
+  ok(document.documentElement.classList.contains("bar"), "Should contain 'bar' class.");
+  ok(!document.documentElement.classList.contains("foobar"), "Shouldn't contain 'foobar' class.");
+
+  document.documentElement.classList.add("foobar");
+  is(document.documentElement.classList.length, 3, "Should have 3 classes.");
+  ok(document.documentElement.classList.contains("foo"), "Should contain 'foo' class.");
+  ok(document.documentElement.classList.contains("bar"), "Should contain 'bar' class.");
+  ok(document.documentElement.classList.contains("foobar"), "Should contain 'foobar' class.");
+
+  document.documentElement.classList.remove("foobar");
+  is(document.documentElement.classList.length, 2, "Should have 2 classes.");
+  ok(document.documentElement.classList.contains("foo"), "Should contain 'foo' class.");
+  ok(document.documentElement.classList.contains("bar"), "Should contain 'bar' class.");
+  ok(!document.documentElement.classList.contains("foobar"), "Shouldn't contain 'foobar' class.");
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_bug616841.xhtml b/dom/base/test/chrome/test_bug616841.xhtml
new file mode 100644
index 0000000000..f5907f0b0b
--- /dev/null
+++ b/dom/base/test/chrome/test_bug616841.xhtml
@@ -0,0 +1,30 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=616841
+-->
+<window title="Mozilla Bug 616841"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=616841"
+     target="_blank">Mozilla Bug 616841</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+  SimpleTest.waitForExplicitFinish();
+
+  function done() {
+    SimpleTest.finish();
+  }
+
+  addLoadEvent(function() {
+    window.openDialog("file_bug616841.xhtml", "", "chrome,noopener", window);
+  });
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug635835.xhtml b/dom/base/test/chrome/test_bug635835.xhtml
new file mode 100644
index 0000000000..69bb3ae68b
--- /dev/null
+++ b/dom/base/test/chrome/test_bug635835.xhtml
@@ -0,0 +1,36 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=635835
+-->
+<window title="Mozilla Bug 635835"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=635835"
+     target="_blank">Mozilla Bug 635835</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+SimpleTest.waitForExplicitFinish();
+const SHOW_ALL = NodeFilter.SHOW_ALL;
+
+addLoadEvent(function() {
+  var walker = document.createTreeWalker(document, SHOW_ALL, null);
+  try {
+    walker.currentNode = {};
+    walker.nextNode();
+  }
+  catch (e) {
+    // do nothing - this is a crash test
+  }
+  ok(true, "Crash test passed");
+  SimpleTest.finish();
+});
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug682305.html b/dom/base/test/chrome/test_bug682305.html
new file mode 100644
index 0000000000..d500dc91d5
--- /dev/null
+++ b/dom/base/test/chrome/test_bug682305.html
@@ -0,0 +1,150 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=682305
+-->
+<head>
+  <title>XMLHttpRequest send and channel implemented in JS</title>
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="application/javascript"  src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank"
+   href="https://bugzilla.mozilla.org/show_bug.cgi?id=682305">Mozilla Bug 682305</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+<script class="testbody" type="application/javascript">
+
+"use strict";
+
+SimpleTest.waitForExplicitFinish();
+
+/*
+ * Register a custom nsIProtocolHandler service
+ * in order to be able to implement *and use* an
+ * nsIChannel component written in Javascript.
+ */
+
+const { ComponentUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/ComponentUtils.sys.mjs"
+);
+
+var contentSecManager = Cc["@mozilla.org/contentsecuritymanager;1"]
+                          .getService(Ci.nsIContentSecurityManager);
+
+var PROTOCOL_SCHEME = "jsproto";
+
+
+function CustomChannel(uri, loadInfo) {
+  this.URI = this.originalURI = uri;
+  this.loadInfo = loadInfo;
+}
+CustomChannel.prototype = {
+  URI: null,
+  originalURI: null,
+  loadInfo: null,
+  contentCharset: "utf-8",
+  contentLength: 0,
+  contentType: "text/plain",
+  owner: Cc["@mozilla.org/systemprincipal;1"].createInstance(Ci.nsIPrincipal),
+  securityInfo: null,
+  notificationCallbacks: null,
+  loadFlags: 0,
+  loadGroup: null,
+  name: null,
+  status: Cr.NS_OK,
+  asyncOpen(listener) {
+    // throws an error if security checks fail
+    var outListener = contentSecManager.performSecurityCheck(this, listener);
+    let stream = this.open();
+    try {
+      outListener.onStartRequest(this);
+    } catch (e) {}
+    try {
+      outListener.onDataAvailable(this, stream, 0, stream.available());
+    } catch (e) {}
+    try {
+      outListener.onStopRequest(this, Cr.NS_OK);
+    } catch (e) {}
+  },
+  open() {
+    // throws an error if security checks fail
+    contentSecManager.performSecurityCheck(this, null);
+
+    let data = "bar";
+    let stream = Cc["@mozilla.org/io/string-input-stream;1"].createInstance(Ci.nsIStringInputStream);
+    stream.setData(data, data.length);
+    return stream;
+  },
+  isPending() {
+    return false;
+  },
+  cancel() {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  },
+  suspend() {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  },
+  resume() {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  },
+  QueryInterface: ChromeUtils.generateQI(["nsIChannel", "nsIRequest"]),
+};
+
+
+function CustomProtocol() {}
+CustomProtocol.prototype = {
+  get scheme() {
+    return PROTOCOL_SCHEME;
+  },
+  allowPort: function allowPort() {
+    return false;
+  },
+  newChannel: function newChannel(URI, loadInfo) {
+    return new CustomChannel(URI, loadInfo);
+  },
+  QueryInterface: ChromeUtils.generateQI(["nsISupportsWeakReference", "nsIProtocolHandler"]),
+};
+
+var gFactory = {
+  register() {
+    Services.io.registerProtocolHandler(
+      PROTOCOL_SCHEME,
+      new CustomProtocol(),
+      Ci.nsIProtocolHandler.URI_NORELATIVE |
+        Ci.nsIProtocolHandler.URI_IS_LOCAL_RESOURCE |
+        Ci.nsIProtocolHandler.URI_DANGEROUS_TO_LOAD,
+      -1
+    );
+
+    this.unregister = function() {
+      Services.io.unregisterProtocolHandler(PROTOCOL_SCHEME);
+      delete this.unregister;
+    };
+  },
+};
+
+// Register the custom procotol handler
+gFactory.register();
+
+// Then, checks if XHR works with it
+var xhr = new XMLHttpRequest();
+xhr.open("GET", PROTOCOL_SCHEME + ":foo", true);
+xhr.onload = function() {
+  is(xhr.responseText, "bar", "protocol doesn't work");
+  gFactory.unregister();
+  SimpleTest.finish();
+};
+try {
+  xhr.send(null);
+} catch (e) {
+  ok(false, e);
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/dom/base/test/chrome/test_bug683852.xhtml b/dom/base/test/chrome/test_bug683852.xhtml
new file mode 100644
index 0000000000..1f9e0d9472
--- /dev/null
+++ b/dom/base/test/chrome/test_bug683852.xhtml
@@ -0,0 +1,87 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=683852
+-->
+<window title="Mozilla Bug 683852"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        xmlns:html="http://www.w3.org/1999/xhtml"
+        xmlns:xul="http://www.mozilla.org/keymaster/gaktekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+  <script>
+    <![CDATA[
+      customElements.define("custom-element", class extends XULElement {
+        constructor() {
+          super();
+          const template = document.getElementById("template");
+          this.attachShadow({mode: "open"})
+            .appendChild(template.content.cloneNode(true));
+        }
+      });
+    ]]>
+  </script>
+  <html:template id="template"><xul:box anonid="anon">Anonymous</xul:box></html:template>
+  <custom-element id="custom-element"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=683852"
+     target="_blank" id="link">Mozilla Bug 683852</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+  /** Test for Bug 683852 **/
+  SimpleTest.waitForExplicitFinish();
+
+  const NS_HTML = "http://www.w3.org/1999/xhtml";
+
+  function startTest() {
+    is(document.contains(document), true, "Document should contain itself!");
+
+    let box = document.getElementById("custom-element");
+    is(document.contains(box), true, "Document should contain element in it!");
+    is(box.contains(box), true, "Element should contain itself.")
+    let anon = box.shadowRoot.querySelector("[anonid=anon]");
+    is(document.contains(anon), false, "Document should not contain anonymous element in it!");
+    is(box.contains(anon), false, "Element should not contain anonymous element in it!");
+    is(anon.contains(anon), true, "Anonymous element should contain itself.")
+    is(document.documentElement.contains(box), true, "Element should contain element in it!");
+    is(document.contains(document.createXULElement("foo")), false, "Document shouldn't contain element which is't in the document");
+    is(document.contains(document.createTextNode("foo")), false, "Document shouldn't contain text node which is't in the document");
+
+    var link = document.getElementById("link");
+    is(document.contains(link.firstChild), true,
+       "Document should contain a text node in it.");
+    is(link.contains(link.firstChild), true,
+       "Element should contain a text node in it.");
+    is(link.firstChild.contains(link), false, "text node shouldn't contain its parent.");
+
+    is(document.contains(null), false, "Document shouldn't contain null.");
+
+    var pi = document.createProcessingInstruction("adf", "asd");
+    is(pi.contains(document), false, "Processing instruction shouldn't contain document");
+    document.documentElement.appendChild(pi);
+    document.contains(pi, true, "Document should contain processing instruction");
+
+    var df = document.createRange().createContextualFragment(`<div xmlns="${NS_HTML}">foo</div>`);
+    is(df.contains(df.firstChild), true, "Document fragment should contain its child");
+    is(df.contains(df.firstChild.firstChild), true,
+       "Document fragment should contain its descendant");
+    is(df.contains(df), true, "Document fragment should contain itself.");
+
+    var d = document.implementation.createHTMLDocument("");
+    is(document.contains(d), false,
+       "Document shouldn't contain another document.");
+    is(document.contains(d.createElement("div")), false,
+       "Document shouldn't contain an element from another document.");
+
+    SimpleTest.finish();
+  }
+
+  addLoadEvent(startTest);
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_bug752226-3.xhtml b/dom/base/test/chrome/test_bug752226-3.xhtml
new file mode 100644
index 0000000000..747fb29c4e
--- /dev/null
+++ b/dom/base/test/chrome/test_bug752226-3.xhtml
@@ -0,0 +1,28 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=752226
+-->
+<window title="Mozilla Bug 752226"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=752226"
+     target="_blank">Mozilla Bug 752226</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+  /** Test for Bug 752226 **/
+  try {
+    new File(null);
+  } catch (e) {}
+  ok(true, "Didn't crash");
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_bug752226-4.xhtml b/dom/base/test/chrome/test_bug752226-4.xhtml
new file mode 100644
index 0000000000..242e231a2e
--- /dev/null
+++ b/dom/base/test/chrome/test_bug752226-4.xhtml
@@ -0,0 +1,28 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=752226
+-->
+<window title="Mozilla Bug 752226"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=752226"
+     target="_blank">Mozilla Bug 752226</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+  /** Test for Bug 752226 **/
+  try {
+    new Cu.Sandbox("about:blank", null);
+  } catch (e) {}
+  ok(true, "Didn't crash");
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_bug765993.html b/dom/base/test/chrome/test_bug765993.html
new file mode 100644
index 0000000000..3325c3713d
--- /dev/null
+++ b/dom/base/test/chrome/test_bug765993.html
@@ -0,0 +1,61 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=765993
+-->
+<head>
+  <title>Test for Bug 765993</title>
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="application/javascript"  src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=765993">Mozilla Bug 765993</a>
+<style type="text/css">
+#link1 a { user-select:none; }
+</style>
+<div id="link1"><a href="http://www.mozilla.org/">link1</a></div>
+<div id="link2"><a href="http://www.mozilla.org/">link2</a></div>
+<p id="display"></p>
+<div id="content" style="display: none">
+  
+</div>
+<pre id="test">
+<script type="application/javascript">
+
+/** Test for Bug 765993 **/
+
+const {addDebuggerToGlobal} = ChromeUtils.importESModule("resource://gre/modules/jsdebugger.sys.mjs");
+addDebuggerToGlobal(globalThis);
+
+window.onload = function() {
+    SimpleTest.waitForExplicitFinish();
+
+    var iframe = document.createElement("iframe");
+    iframe.src = "http://mochi.test:8888/tests/dom/base/test/chrome/nochrome_bug765993.html";
+    iframe.onload = function() {
+        var script = iframe.contentWindow.document.createElement("script");
+        script.src = "http://mochi.test:8888/tests/dom/base/test/chrome/nochrome_bug765993.js";
+        script.onload = function() {
+            var dbg = new Debugger(iframe.contentWindow);
+            ok(dbg, "Should be able to create debugger");
+
+            var scripts = dbg.findScripts({
+                url: "http://mochi.test:8888/tests/dom/base/test/chrome/nochrome_bug765993.js",
+            });
+            ok(scripts.length, "Should be able to find script");
+
+            is(scripts[0].source.sourceMapURL, "foo.js.map");
+            SimpleTest.finish();
+        };
+
+        iframe.contentWindow.document.body.appendChild(script);
+    };
+
+    document.body.appendChild(iframe);
+};
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/dom/base/test/chrome/test_bug780199.xhtml b/dom/base/test/chrome/test_bug780199.xhtml
new file mode 100644
index 0000000000..e27afb72fa
--- /dev/null
+++ b/dom/base/test/chrome/test_bug780199.xhtml
@@ -0,0 +1,51 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=780199
+-->
+<window title="Mozilla Bug 780199"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        onload="test()">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=780199"
+     target="_blank">Mozilla Bug 780199</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+
+  /** Test for Bug 780199 **/
+
+  SimpleTest.waitForExplicitFinish();
+
+  var b;
+
+  function callback(r) {
+    is(r[0].type, "attributes");
+    is(r[0].oldValue, b.getAttribute("src"));
+    setTimeout(continueTest, 500);
+  }
+
+  function continueTest() {
+    // Check that a new page wasn't loaded.
+    is(b.contentDocument.documentElement.textContent, "testvalue");
+    SimpleTest.finish();
+  }
+
+  function test() {
+    b = document.getElementById("b");
+    var m = new MutationObserver(callback);
+    m.observe(b, { attributes: true, attributeOldValue: true });
+    b.contentDocument.documentElement.textContent = "testvalue";
+    b.setAttribute("src", b.getAttribute("src"));
+  }
+
+  ]]>
+  </script>
+  <browser id="b" src="data:text/plain,initial"/>
+</window>
diff --git a/dom/base/test/chrome/test_bug780529.xhtml b/dom/base/test/chrome/test_bug780529.xhtml
new file mode 100644
index 0000000000..bf8b8b2981
--- /dev/null
+++ b/dom/base/test/chrome/test_bug780529.xhtml
@@ -0,0 +1,36 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=780529
+-->
+<window title="Mozilla Bug 780529"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=780529"
+     target="_blank">Mozilla Bug 780529</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+  /** Test for Bug 780529 **/
+var req = new XMLHttpRequest();
+req.open("GET", "", true);
+// Have to call send() to get the XHR hooked up as the notification callbacks
+req.send();
+var callbacks = req.channel.notificationCallbacks;
+var sink = callbacks.getInterface(Ci.nsIChannelEventSink);
+ok(sink instanceof Ci.nsIChannelEventSink,
+   "Should be a channel event sink")
+ok("asyncOnChannelRedirect" in sink,
+   "Should have the right methods for an event sink");
+
+let sinkReq = sink.QueryInterface(Ci.nsIInterfaceRequestor);
+isnot(sinkReq, callbacks, "Sink should not be the XHR object");
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_bug800386.xhtml b/dom/base/test/chrome/test_bug800386.xhtml
new file mode 100644
index 0000000000..c176bd9b8e
--- /dev/null
+++ b/dom/base/test/chrome/test_bug800386.xhtml
@@ -0,0 +1,65 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=800386
+-->
+<window title="Mozilla Bug 800386"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=800386"
+     target="_blank">Mozilla Bug 800386</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+  /** Test for Bug 800386 **/
+  SimpleTest.waitForExplicitFinish();
+
+  var triedForwarding = false;
+  var forwardFailed = false;
+
+  var xhr = new XMLHttpRequest;
+  var xhr2 = new XMLHttpRequest;
+
+  var eventSink = xhr.getInterface(Ci.nsIProgressEventSink);
+  isnot(eventSink, null, "Should get event sink directly!");
+
+  // Now jump through some hoops to get us a getInterface call from C++
+
+  var requestor = {
+    getInterface(aIID) {
+      if (aIID.equals(Ci.nsIProgressEventSink)) {
+        triedForwarding = true;
+        try {
+          return xhr2.getInterface(aIID);
+        } catch (e) {
+          forwardFailed = true;
+        }
+      }
+      throw Components.Exception("", Cr.NS_ERROR_NO_INTERFACE);
+    },
+
+    QueryInterface: ChromeUtils.generateQI(["nsIInterfaceRequestor"])
+  };
+
+  // HTTP URI so that we get progress callbacks
+  xhr.open("GET", "http://mochi.test:8888/", false);
+  xhr.channel.notificationCallbacks = requestor;
+  xhr.onreadystatechange = function() {
+    if (xhr.readyState == 4) {
+      ok(triedForwarding,
+         "Should have had an attempt to treat us as a progress event sink");
+      ok(!forwardFailed,
+         "Should have been able to forward getInterface on to the XHR");
+      SimpleTest.finish();
+    }
+  }
+  xhr.send();
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_bug816340.xhtml b/dom/base/test/chrome/test_bug816340.xhtml
new file mode 100644
index 0000000000..3e45fd7245
--- /dev/null
+++ b/dom/base/test/chrome/test_bug816340.xhtml
@@ -0,0 +1,32 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=816340
+-->
+<window title="Mozilla Bug 816340"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=816340"
+     target="_blank">Mozilla Bug 816340</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script>
+  SimpleTest.waitForExplicitFinish();
+
+  function done() {
+    SimpleTest.finish();
+  }
+
+  SpecialPowers.pushPrefEnv({
+    set: [["dom.forms.fieldset_disable_only_descendants.enabled", true]]
+  }).then(() => {
+      window.openDialog("file_bug816340.xhtml", "", "chrome,noopener", window);
+  });
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_bug884693.xhtml b/dom/base/test/chrome/test_bug884693.xhtml
new file mode 100644
index 0000000000..7d89ba25bc
--- /dev/null
+++ b/dom/base/test/chrome/test_bug884693.xhtml
@@ -0,0 +1,79 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=884693
+-->
+<window title="Mozilla Bug 884693"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=884693"
+     target="_blank">Mozilla Bug 884693</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+    const SERVER_URL = "http://mochi.test:8888/tests/dom/base/test/chrome/bug884693.sjs";
+    const INVALID_XML = "InvalidXML";
+    const XML_WITHOUT_ROOT = "<?xml version='1.0'?>";
+
+    function runTest(status, statusText, body, expectedResponse, expectedMessages)
+    {
+      return new Promise((resolve, reject) => {
+        Services.console.reset();
+
+        let xhr = new XMLHttpRequest();
+
+        xhr.onload = () => {
+          is(xhr.responseText, expectedResponse, "Correct responseText returned");
+
+          let messages = Services.console.getMessageArray() || [];
+          // broadcastlisteners can happen and cause false alarm.
+          messages = messages.filter(msg =>
+            !(msg instanceof Ci.nsIScriptError &&
+              msg.category.includes("chrome javascript") &&
+              msg.message.includes("Unknown event")));
+
+          if (messages.length) {
+            info(`Got console messages ${messages}`);
+          }
+          is(messages.length, expectedMessages.length, "Got expected message count");
+          messages = messages.map(m => m.message).join(",");
+          for(let message of expectedMessages) {
+            ok(messages.includes(message), "Got expected message: " + message);
+          }
+
+          resolve();
+        };
+
+        xhr.onerror = e => {
+          reject(e);
+        };
+
+        xhr.open("GET", `${SERVER_URL}?${status}&${statusText}&${body}`);
+        xhr.send();
+      });
+    }
+
+    SimpleTest.waitForExplicitFinish();
+    runTest(201, "Created", "", "", []).
+      then(() => { return runTest(201, "Created", INVALID_XML, INVALID_XML, []); }).
+      then(() => { return runTest(202, "Accepted", "", "", []); }).
+      then(() => { return runTest(202, "Accepted", INVALID_XML, INVALID_XML, []); }).
+      then(() => { return runTest(204, "No Content", "", "", []); }).
+      then(() => { return runTest(204, "No Content", INVALID_XML, "", []); }).
+      then(() => { return runTest(205, "Reset Content", "", "", []); }).
+      then(() => { return runTest(205, "Reset Content", INVALID_XML, "", []); }).
+      then(() => { return runTest(304, "Not modified", "", "", []); }).
+      then(() => { return runTest(304, "Not modified", INVALID_XML, "", []); }).
+      then(() => { return runTest(200, "OK", "", "", []); }).
+      then(() => { return runTest(200, "OK", XML_WITHOUT_ROOT, XML_WITHOUT_ROOT, ["no root element found"]); }).
+      then(() => { return runTest(200, "OK", INVALID_XML, INVALID_XML, ["syntax error"]); }).
+      then(SimpleTest.finish);
+
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_bug914381.html b/dom/base/test/chrome/test_bug914381.html
new file mode 100644
index 0000000000..eb82ffd0f7
--- /dev/null
+++ b/dom/base/test/chrome/test_bug914381.html
@@ -0,0 +1,58 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=650776
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 914381</title>
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=914381">Mozilla Bug 914381</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+</div>
+<pre id="test">
+<script type="application/javascript">
+function createFileWithData(fileData) {
+  var testFile = Services.dirsvc.get("ProfD", Ci.nsIFile);
+  testFile.append("testBug914381");
+
+  var outStream = Cc["@mozilla.org/network/file-output-stream;1"].createInstance(Ci.nsIFileOutputStream);
+  outStream.init(testFile, 0x02 | 0x08 | 0x20, // write, create, truncate
+                 0o666, 0);
+  outStream.write(fileData, fileData.length);
+  outStream.close();
+
+  return testFile;
+}
+
+/** Test for Bug 914381. File's created in JS using an nsIFile should allow mozGetFullPathInternal calls to succeed **/
+var file = createFileWithData("Test bug 914381");
+
+SpecialPowers.pushPrefEnv({ set: [["dom.file.createInChild", true]]})
+.then(() => {
+  return File.createFromNsIFile(file);
+})
+.then(f => {
+  is(f.mozFullPathInternal, undefined, "mozFullPathInternal is undefined from js");
+  is(f.mozFullPath, file.path, "mozFullPath returns path if created with nsIFile");
+})
+.then(() => {
+  return File.createFromFileName(file.path);
+})
+.then(f => {
+  is(f.mozFullPathInternal, undefined, "mozFullPathInternal is undefined from js");
+  is(f.mozFullPath, "", "mozFullPath returns blank if created with a string");
+})
+.then(() => {
+  SimpleTest.finish();
+});
+
+SimpleTest.waitForExplicitFinish();
+</script>
+</pre>
+</body>
+</html>
diff --git a/dom/base/test/chrome/test_bug990812.xhtml b/dom/base/test/chrome/test_bug990812.xhtml
new file mode 100644
index 0000000000..410d6d2367
--- /dev/null
+++ b/dom/base/test/chrome/test_bug990812.xhtml
@@ -0,0 +1,42 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=990812
+-->
+<window title="Mozilla Bug 990812"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=990812"
+     target="_blank">Mozilla Bug 990812</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+  SimpleTest.waitForExplicitFinish();
+
+  var tests = [
+    "file_bug990812-1.xhtml",
+    "file_bug990812-2.xhtml",
+    "file_bug990812-3.xhtml",
+    "file_bug990812-4.xhtml",
+    "file_bug990812-5.xhtml",
+  ];
+
+  function next() {
+    if (tests.length) {
+      var file = tests.shift();
+      info("-- running " + file);
+      window.openDialog(file, "_blank", "chrome,noopener", window);
+    } else {
+      SimpleTest.finish();
+    }
+  }
+
+  addLoadEvent(next);
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_chromeOuterWindowID.xhtml b/dom/base/test/chrome/test_chromeOuterWindowID.xhtml
new file mode 100644
index 0000000000..1feb7c7c74
--- /dev/null
+++ b/dom/base/test/chrome/test_chromeOuterWindowID.xhtml
@@ -0,0 +1,138 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1474662
+Test that the chromeOuterWindowID on the MessageManager interface
+works, and that it properly updates when swapping frameloaders between
+windows.
+-->
+<window title="Mozilla Bug 1474662"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1474662"
+     target="_blank">Mozilla Bug 1474662</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+  SimpleTest.waitForExplicitFinish();
+  const {BrowserTestUtils} = ChromeUtils.importESModule(
+    "resource://testing-common/BrowserTestUtils.sys.mjs"
+  );
+
+  const BROWSER_DOC = "window_chromeOuterWindowID.xhtml";
+  const TEST_PAGE = "http://example.com";
+  const TEST_PAGE_2 = "http://example.com/browser";
+
+  function getOuterWindowID(win) {
+    return win.docShell.outerWindowID;
+  }
+
+  /**
+   * Takes two <xul:browser>'s that should be in the same document, and
+   * ensures that their frame script environments know the correct value
+   * of the host window's outerWindowID.
+   */
+  async function ensureExpectedChromeOuterWindowIDs(browser1, browser2) {
+    is(browser1.ownerDocument, browser2.ownerDocument,
+       "Both browsers should belong to the same document.");
+    let winID = getOuterWindowID(browser1.ownerGlobal);
+
+    let getChildRootOuterId = browser => { 
+      try {
+        return docShell.browserChild?.chromeOuterWindowID;
+      } catch(ex) { }
+
+      // Not a remote tab
+      return content.top.windowRoot.ownerGlobal.docShell.outerWindowID;
+    };
+
+    let browser1ID = await SpecialPowers.spawn(browser1, [], getChildRootOuterId);
+    let browser2ID = await SpecialPowers.spawn(browser2, [], getChildRootOuterId);
+
+    is(browser1ID, winID,
+       "Browser 1 frame script environment should have the correct chromeOuterWindowID");
+    is(browser2ID, winID,
+       "Browser 1 frame script environment should have the correct chromeOuterWindowID");
+  }
+
+  /**
+   * Opens up a BROWSER_DOC test window, and points each browser to a particular
+   * page.
+   *
+   * @param num (Number)
+   *        An identifier number for this window. Mainly used as a suffix for the
+   *        returned values.
+   * @param page (String)
+   *        A URL to load in each <xul:browser>
+   * @returns Promise
+   *        The Promise resolves with an object with the following properties:
+   *
+   *        win<num>: a reference to the opened window
+   *        remote<num>: a reference to the remote browser in the window
+   *        nonRemote<num>: a reference to the non-remote browser in the window
+   */
+  async function prepareWindow(num, page) {
+    let win = window.browsingContext.topChromeWindow.open(BROWSER_DOC, "bug1474662-" + num, "chrome,width=200,height=200");
+    await BrowserTestUtils.waitForEvent(win, "load");
+    let remote = win.document.getElementById("remote");
+    let nonRemote = win.document.getElementById("non-remote");
+
+    ok(remote && remote.isRemoteBrowser,
+       "Should have found a remote browser in test window " + num);
+    ok(nonRemote && !nonRemote.isRemoteBrowser,
+       "Should have found a non-remote browser in test window " + num);
+
+    BrowserTestUtils.startLoadingURIString(remote, page);
+    await BrowserTestUtils.browserLoaded(remote);
+    BrowserTestUtils.startLoadingURIString(nonRemote, page);
+    await BrowserTestUtils.browserLoaded(nonRemote);
+
+    let result = {};
+    result["win" + num] = win;
+    result["remote" + num] = remote;
+    result["nonRemote" + num] = nonRemote;
+    return result;
+  }
+
+  add_task(async () => {
+    let { win1, remote1, nonRemote1 } = await prepareWindow(1, TEST_PAGE);
+    let { win2, remote2, nonRemote2 } = await prepareWindow(2, TEST_PAGE_2);
+
+    let win1ID = getOuterWindowID(win1);
+    let win2ID = getOuterWindowID(win2);
+
+    // Quick sanity-test here - if something has gone horribly wrong
+    // and the windows have the same IDs, then the rest of this test
+    // is meaningless.
+    isnot(win1ID, win2ID,
+          "The windows should definitely have different IDs.");
+
+    await ensureExpectedChromeOuterWindowIDs(remote1, nonRemote1);
+    await ensureExpectedChromeOuterWindowIDs(remote2, nonRemote2);
+
+    // Swap the frameloaders! This doesn't swap the <browser> elements though,
+    // so what's expected is that the IDs should remain the same within
+    // the browsers despite the underlying content changing.
+    remote1.swapFrameLoaders(remote2);
+    nonRemote1.swapFrameLoaders(nonRemote2);
+
+    await ensureExpectedChromeOuterWindowIDs(remote1, nonRemote1);
+    await ensureExpectedChromeOuterWindowIDs(remote2, nonRemote2);
+
+    // Now swap them back.
+    remote1.swapFrameLoaders(remote2);
+    nonRemote1.swapFrameLoaders(nonRemote2);
+
+    await ensureExpectedChromeOuterWindowIDs(remote1, nonRemote1);
+    await ensureExpectedChromeOuterWindowIDs(remote2, nonRemote2);
+
+    await BrowserTestUtils.closeWindow(win1);
+    await BrowserTestUtils.closeWindow(win2);
+  });
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_custom_element_content.xhtml b/dom/base/test/chrome/test_custom_element_content.xhtml
new file mode 100644
index 0000000000..7778bc350e
--- /dev/null
+++ b/dom/base/test/chrome/test_custom_element_content.xhtml
@@ -0,0 +1,55 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1130028
+-->
+<window title="Mozilla Bug 1130028"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1130028"
+     target="_blank">Mozilla Bug 1130028</a>
+  <iframe onload="startTests()" id="frame" src="http://example.com/chrome/dom/base/test/chrome/frame_custom_element_content.html"></iframe>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+  /** Test for Bug 1130028 **/
+  var connectedCallbackCount = 0;
+
+  function startTests() {
+    var frame = $("frame");
+
+    class XFoo extends frame.contentWindow.HTMLElement {};
+    frame.contentWindow.customElements.define("x-foo", XFoo);
+    var elem = new XFoo();
+    is(elem.tagName, "X-FOO", "Constructor should create an x-foo element.");
+
+    class XBar extends frame.contentWindow.HTMLElement {
+      constructor() {
+        super();
+        this.magicNumber = 42;
+      }
+
+      connectedCallback() {
+        connectedCallbackCount++;
+        // Callback should be called only once by element created in content.
+        is(connectedCallbackCount, 1, "Connected callback called, should be called once in test.");
+        is(this.magicNumber, 42, "Callback should be able to see the custom prototype.");
+      }
+    };
+
+    frame.contentWindow.customElements.define("x-bar", XBar);
+    is(connectedCallbackCount, 1, "Connected callback should be called by element created in content.");
+
+    var element = frame.contentDocument.createElement("x-bar");
+    is(element.magicNumber, 42, "Should be able to see the custom prototype on created element.");
+  }
+
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_custom_element_ep.xhtml b/dom/base/test/chrome/test_custom_element_ep.xhtml
new file mode 100644
index 0000000000..28b4e876f5
--- /dev/null
+++ b/dom/base/test/chrome/test_custom_element_ep.xhtml
@@ -0,0 +1,41 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1130028
+-->
+<window title="Mozilla Bug 1130028"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1130028"
+     target="_blank">Mozilla Bug 1130028</a>
+  <iframe onload="startTests()" id="frame" src="http://example.com/chrome/dom/base/test/chrome/frame_custom_element_content.html"></iframe>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+
+  /** Test for Bug 1130028 **/
+  SimpleTest.waitForExplicitFinish();
+
+  function finishTest(canSeePrototype) {
+    ok(true, "connectedCallback called when reigsterElement was called with an extended principal.");
+    ok(canSeePrototype, "connectedCallback should be able to see custom prototype.");
+    SimpleTest.finish();
+  }
+
+  function startTests() {
+    var frame = $("frame");
+
+    // Create a sandbox with an extended principal then run a script that registers a custom element in the sandbox.
+    var sandbox = Cu.Sandbox([frame.contentWindow], { sandboxPrototype: frame.contentWindow });
+    sandbox.finishTest = finishTest;
+    Services.scriptloader.loadSubScript("chrome://mochitests/content/chrome/dom/base/test/chrome/custom_element_ep.js", sandbox);
+  }
+
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_document-element-inserted.xhtml b/dom/base/test/chrome/test_document-element-inserted.xhtml
new file mode 100644
index 0000000000..5fd35e364d
--- /dev/null
+++ b/dom/base/test/chrome/test_document-element-inserted.xhtml
@@ -0,0 +1,54 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1411707
+-->
+<window title="Mozilla Bug 1411707"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1411707"
+     target="_blank">Mozilla Bug 1411707</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+    SimpleTest.waitForExplicitFinish();
+
+    const OUTER_URL = "chrome://mochitests/content/chrome/dom/base/test/chrome/file_document-element-inserted.xhtml";
+    const INNER_URL = "chrome://mochitests/content/chrome/dom/base/test/chrome/file_document-element-inserted-inner.xhtml";
+
+    async function waitForEvent(url) {
+      return new Promise(resolve => {
+        SpecialPowers.addObserver(function inserted(document) {
+          is(document.documentURI, url, "Correct URL");
+          is(document.readyState, "loading", "Correct readyState");
+          SpecialPowers.removeObserver(inserted, "document-element-inserted");
+          resolve();
+        }, "document-element-inserted");
+      })
+    }
+
+    // Load a XUL document that also has an iframe to a subdocument, and
+    // expect both events to fire with the docs in the correct state.
+    async function testEvents() {
+      info(`Waiting for events after loading ${OUTER_URL}`);
+      let win = window.browsingContext.topChromeWindow.openDialog(OUTER_URL, "_blank", "chrome,dialog=no,all");
+      await waitForEvent(OUTER_URL);
+      await waitForEvent(INNER_URL);
+      win.close();
+    }
+
+    (async function() {
+      // Test the same document twice to make to make sure we are
+      // firing properly when loading the protype document.
+      await testEvents();
+      await testEvents();
+      SimpleTest.finish();
+    })();
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_domparsing.xhtml b/dom/base/test/chrome/test_domparsing.xhtml
new file mode 100644
index 0000000000..48a7d43b6a
--- /dev/null
+++ b/dom/base/test/chrome/test_domparsing.xhtml
@@ -0,0 +1,145 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>
+<window title="Test for the Mozilla extesion of the DOM Parsing and Serialization API"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml"
+        xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=816410"
+     target="_blank">Mozilla Bug 816410</a>
+  <xul:browser id="test1" type="content" src="data:text/html,content" />
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+"use strict";
+/** Test for Bug 816410 **/
+
+function throws(fn, type, message) {
+  try {
+    fn();
+    ok(false, message);
+  } catch (e) {
+    if (type) {
+      is(e.name, type, message);
+    } else {
+      ok(true, message);
+    }
+  }
+}
+
+add_task(function dom_parser_extra_args() {
+  // DOMParser constructor should not throw for extra arguments
+  new DOMParser(undefined);
+  new DOMParser(null);
+  new DOMParser(false);
+  new DOMParser(0);
+  new DOMParser("");
+  new DOMParser({});
+});
+
+add_task(function xml_serializer_extra_args() {
+  // XMLSerializer constructor should not throw for extra arguments
+  new XMLSerializer(undefined);
+  new XMLSerializer(null);
+  new XMLSerializer(false);
+  new XMLSerializer(0);
+  new XMLSerializer("");
+  new XMLSerializer({});
+});
+
+add_task(function chrome_window() {
+  runTest(window, true);
+});
+
+add_task(function content_window() {
+  runTest(document.getElementById("test1").contentWindow, false);
+});
+
+function runTest(win, expectSystem) {
+  let parser = new win.DOMParser();
+  let serializer = new win.XMLSerializer();
+  let principal = win.document.nodePrincipal;
+  is(principal.isSystemPrincipal, expectSystem,
+     `expected ${expectSystem ? "system" : "content"} principal`);
+
+  is(typeof parser.parseFromString, "function", "parseFromString should exist");
+  is(typeof parser.parseFromBuffer, "function", "parseFromBuffer should exist");
+  is(typeof parser.parseFromStream, "function", "parseFromStream should exist");
+  is(typeof parser.parseFromSafeString, "function", "parseFromSafeString should exist");
+
+  is(typeof serializer.serializeToString, "function", "serializeToString should exist");
+  is(typeof serializer.serializeToStream, "function", "serializeToStream should exist");
+
+  let tests = [
+    {input: "<html></html>", type: "text/html",
+     expected: '<html xmlns="http://www.w3.org/1999/xhtml"><head></head><body></body></html>'},
+    {input: "<xml></xml>", type: "text/xml", expected: "<xml/>"},
+    {input: "<xml></xml>", type: "application/xml", expected: "<xml/>"},
+    {input: "<html></html>", type: "application/xhtml+xml", expected: "<html/>"},
+    {input: "<svg></svg>", type: "image/svg+xml", expected: "<svg/>"},
+  ];
+  for (let t of tests) {
+    const fromNormalString = parser.parseFromString(t.input, t.type);
+    if (principal.isSystemPrincipal) {
+      ok(fromNormalString.nodePrincipal.isNullPrincipal,
+         "system principal DOMParser produces a null principal document");
+    } else {
+      ok(fromNormalString.nodePrincipal === principal,
+         "content principal DOMParser produces a document with an object-identical principal");
+    }
+
+    const fromSafeString = parser.parseFromSafeString(t.input, t.type);
+    ok(fromSafeString.nodePrincipal === principal,
+       "DOMParser with parseFromSafeString always produces a document with an object-identical principal");
+
+    is(serializer.serializeToString(parser.parseFromString(t.input, t.type)), t.expected,
+       "parseFromString test for " + t.type);
+
+    for (let charset of [null, "UTF-8"]) {
+      let pipe = Cc["@mozilla.org/pipe;1"].createInstance(Ci.nsIPipe);
+      pipe.init(false, false, 0, 0xffffffff, null);
+      let ostream = pipe.outputStream;
+      serializer.serializeToStream(parser.parseFromString(t.input, t.type), ostream, charset);
+      let istream = Cc["@mozilla.org/scriptableinputstream;1"].createInstance(
+        Ci.nsIScriptableInputStream
+      );
+      istream.init(pipe.inputStream);
+      let data = istream.read(0xffffffff);
+      is(data, t.expected,
+         "serializeToStream test for " + t.type + ", charset=" + charset);
+    }
+
+    if (t.type === "text/html") {
+      // parseFromBuffer and parseFromStream don't support "text/html".
+      continue;
+    }
+
+    let array = Array.from(t.input, function(c) { return c.charCodeAt(c); });
+    let inputs = [
+      {array, name: "parseFromBuffer (array)"},
+      {array: new Uint8Array(array), name: "parseFromBuffer (Uint8Array)"},
+    ];
+    for (let input of inputs) {
+      let a = input.array;
+      is(serializer.serializeToString(parser.parseFromBuffer(a, t.type)), t.expected,
+         input.name + " test for " + t.type);
+    }
+
+    let istream = Cc["@mozilla.org/io/string-input-stream;1"].
+                  createInstance(Ci.nsIStringInputStream);
+    for (let charset of [null, "UTF-8"]) {
+      istream.setData(t.input, -1);
+      is(serializer.serializeToString(parser.parseFromStream(istream, charset, t.input.length, t.type)),
+         t.expected, "parseFromStream test for " + t.type + ", charset=" + charset);
+    }
+  }
+  throws(function() {
+    parser.parseFromString("<xml></xml>", "foo/bar");
+  }, "TypeError", "parseFromString should throw for the unknown type");
+}
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_fileconstructor.xhtml b/dom/base/test/chrome/test_fileconstructor.xhtml
new file mode 100644
index 0000000000..8884eb169b
--- /dev/null
+++ b/dom/base/test/chrome/test_fileconstructor.xhtml
@@ -0,0 +1,86 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet
+  href="chrome://mochikit/content/tests/SimpleTest/test.css"
+  type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=607114.xul
+-->
+<window title="Mozilla Bug 607114"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+
+  <script type="application/javascript"
+    src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+<body  xmlns="http://www.w3.org/1999/xhtml">
+<a target="_blank"
+   href="https://bugzilla.mozilla.org/show_bug.cgi?id=607114">
+   Mozilla Bug 607114</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+</pre>
+</body>
+
+<script class="testbody" type="application/javascript">
+<![CDATA[
+
+/** Test for Bug 607114 **/
+
+// eslint-disable-next-line mozilla/no-addtask-setup
+add_task(async function setup() {
+  await SpecialPowers.pushPrefEnv({ set: [[ "dom.file.createInChild", true ]]});
+});
+
+add_task(async function test() {
+  var file = SpecialPowers.Services.dirsvc.get("CurWorkD", Ci.nsIFile);
+  // man I wish this were simpler ...
+  file.append("chrome");
+  file.append("dom");
+  file.append("base");
+  file.append("test");
+  file.append("chrome");
+  file.append("fileconstructor_file.png");
+
+  let domFile = await File.createFromFileName(file.path);
+
+  ok(File.isInstance(domFile), "File() should return a File");
+  is(domFile.type, "image/png", "File should be a PNG");
+  is(domFile.size, 95, "File has size 95 (and more importantly we can read it)");
+
+  domFile = await File.createFromNsIFile(file);
+  ok(File.isInstance(domFile), "File() should return a File for an nsIFile");
+  is(domFile.type, "image/png", "File should be a PNG");
+  is(domFile.size, 95, "File has size 95 (and more importantly we can read it)");
+
+  try {
+    await File.createFromFileName(
+      "i/sure/hope/this/does/not/exist/anywhere.txt"
+    );
+    ok(false, "Attempt to construct a non-existent file should fail.");
+  } catch (ex) {
+    is(
+      ex.result,
+      Cr.NS_ERROR_FILE_UNRECOGNIZED_PATH,
+      "Constructing a non-existing file should fail with the correct error code"
+    );
+  }
+  let dir = SpecialPowers.Services.dirsvc.get("CurWorkD", Ci.nsIFile);
+  try {
+    await File.createFromNsIFile(dir);
+    ok(false, "Attempt to construct a file from a directory should fail.");
+  } catch (ex) {
+    is(
+      ex.result,
+      Cr.NS_ERROR_FILE_IS_DIRECTORY,
+      "Constructing a file from a directory should fail with the correct error code"
+    );
+  }
+})
+]]>
+</script>
+
+</window>
diff --git a/dom/base/test/chrome/test_getElementsWithGrid.html b/dom/base/test/chrome/test_getElementsWithGrid.html
new file mode 100644
index 0000000000..3554acb2e9
--- /dev/null
+++ b/dom/base/test/chrome/test_getElementsWithGrid.html
@@ -0,0 +1,121 @@
+<!doctype html>
+<html id="root" class="g">
+<head>
+<meta charset="utf-8">
+<script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+<link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css" />
+<style>
+.no-match {
+  display: block;
+}
+.g {
+  display: grid;
+}
+.s {
+  display: subgrid;
+}
+.gi {
+  display: inline-grid;
+}
+</style>
+
+<script>
+"use strict";
+
+SimpleTest.waitForExplicitFinish();
+
+function testTargetsAreInElements(targets, elements) {
+  let c = 0;
+  for (let target of targets) {
+    if (c >= elements.length) {
+      ok(false, "We shouldn't have more targets than elements found.");
+      break;
+    }
+    let element = elements[c];
+    let isMatching = (target.id == element.id);
+    let test_function = (target.todo ? todo : ok);
+
+    test_function(isMatching, "Should find " + target.message + ".");
+
+    // Only move to the next element in the elements if this one was a match.
+    // This handles the case of an unexpected element showing up, and prevents
+    // cascading errors in that case. If we've instead screwed up the target
+    // list, then we will get cascading errors.
+    if (isMatching) {
+      ++c;
+    }
+  }
+
+  // Make sure we don't have any extra elements after going through all the targets.
+  is(c, elements.length, "We shouldn't have more elements than we have targets.");
+}
+
+function runTests() {
+  // Part 1: Look for all the grid elements starting from the document root.
+  let elementsFromRoot = document.documentElement.getElementsWithGrid();
+
+  // Check that the expected elements were returned.
+  // Targets are provided in order we expect them to appear.
+  // Has to end in a non-todo element in order for testing logic to work.
+  let targetsFromRoot = [
+    {id: "root", message: "root with display:grid"},
+    {id: "a", message: "'plain' grid container with display:grid"},
+    {id: "b", message: "display:subgrid inside display:grid (to be fixed in Bug 1240834)", todo: true},
+    {id: "c", message: "'plain' grid container with display:inline-grid"},
+    {id: "d", message: "display:subgrid inside display:inline-grid (to be fixed in Bug 1240834)", todo: true},
+    {id: "e", message: "grid container with visibility:hidden"},
+    {id: "f", message: "grid container inside an element"},
+    {id: "g", message: "overflow:scroll grid container"},
+    {id: "h", message: "button as a grid container"},
+    {id: "i", message: "fieldset as a grid container"},
+    {id: "k1", message: "grid container containing a grid container"},
+    {id: "k2", message: "grid container inside a grid container"},
+  ];
+  is(elementsFromRoot.length, 10, "Found expected number of elements within document root.");
+  testTargetsAreInElements(targetsFromRoot, elementsFromRoot);
+
+
+  // Part 2: Look for all the grid elements starting from a non-root element.
+  let elementsFromNonRoot = document.getElementById("a_non_root_element").getElementsWithGrid();
+
+  let targetsFromNonRoot = [
+    {id: "f", message: "grid container inside an element (from non-root element)"},
+  ];
+  is(elementsFromNonRoot.length, 1, "Found expected number of elements from non-root element.");
+  testTargetsAreInElements(targetsFromNonRoot, elementsFromNonRoot);
+
+  SimpleTest.finish();
+}
+</script>
+</head>
+<body onLoad="runTests();">
+
+<div id="a" class="g">
+  <div class="no-match"></div>
+  <div id="b" class="s"></div>
+</div>
+
+<div class="no-match"></div>
+
+<div id="c" class="gi">
+  <div id="d" class="s"></div>
+</div>
+
+<div id="e" class="g" style="visibility:hidden"></div>
+
+<div id="a_non_root_element"><div id="f" class="g"></div></div>
+
+<div class="no-match"></div>
+
+<div id="g" style="overflow:scroll" class="g"></div>
+
+<button id="h" class="g"></button>
+
+<fieldset id="i" class="g"></fieldset>
+
+<div id="a_display_none_element" style="display:none"><div id="j" class="g"></div></div>
+
+<div id="k1" class="g"><div id="k2" class="g"></div></div>
+
+</body>
+</html>
diff --git a/dom/base/test/chrome/test_input_value_set_preserve_undo.xhtml b/dom/base/test/chrome/test_input_value_set_preserve_undo.xhtml
new file mode 100644
index 0000000000..80465202ab
--- /dev/null
+++ b/dom/base/test/chrome/test_input_value_set_preserve_undo.xhtml
@@ -0,0 +1,37 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>
+<window title="Bug 1676785"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+<script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+<script src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
+<html:body>
+  <xul:hbox>
+    <html:input id="xul" />
+  </xul:hbox>
+  <html:div>
+    <html:input id="non-xul" />
+  </html:div>
+</html:body>
+<script class="testbody">
+SimpleTest.waitForExplicitFinish();
+
+function shouldPreserveHistory(input, preserve) {
+  input.focus();
+  input.value = "abc";
+  input.value = "def";
+  let ctrl = navigator.platform.indexOf("Mac") == 0 ? { metaKey: true } : { ctrlKey: true };
+  synthesizeKey("z", ctrl);
+  (preserve ? is : isnot)(input.value, "abc", `Expected ${input.id} to ${preserve ? "" : "not "}preserve undo history when setting .value`);
+}
+
+window.onload = function() {
+  shouldPreserveHistory(document.getElementById("xul"), true);
+  shouldPreserveHistory(document.getElementById("non-xul"), false);
+
+  SimpleTest.finish();
+}
+</script>
+</window>
diff --git a/dom/base/test/chrome/test_nsITextInputProcessor.xhtml b/dom/base/test/chrome/test_nsITextInputProcessor.xhtml
new file mode 100644
index 0000000000..3343c28560
--- /dev/null
+++ b/dom/base/test/chrome/test_nsITextInputProcessor.xhtml
@@ -0,0 +1,29 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<window title="Testing nsITextInputProcessor behavior"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+<body xmlns="http://www.w3.org/1999/xhtml">
+<p id="display">
+</p>
+<div id="content" style="display: none">
+  
+</div>
+<pre id="test">
+</pre>
+</body>
+
+<script class="testbody" type="application/javascript">
+<![CDATA[
+
+SimpleTest.waitForExplicitFinish();
+window.openDialog("window_nsITextInputProcessor.xhtml", "_blank", 
+                  "chrome,width=600,height=600,noopener", window);
+
+]]>
+</script>
+</window>
diff --git a/dom/base/test/chrome/test_nsITextInputProcessorCallback_at_changing_default_value_of_textarea.html b/dom/base/test/chrome/test_nsITextInputProcessorCallback_at_changing_default_value_of_textarea.html
new file mode 100644
index 0000000000..179ffee086
--- /dev/null
+++ b/dom/base/test/chrome/test_nsITextInputProcessorCallback_at_changing_default_value_of_textarea.html
@@ -0,0 +1,107 @@
+<!doctype html>
+<html>
+<head>
+<meta charset="utf-8">
+<title>Text change notifications at updating default value of non-dirty textarea</title>
+<script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+<link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css">
+<script>
+"use strict";
+
+SimpleTest.waitForExplicitFinish();
+SimpleTest.waitForFocus(async () => {
+  const textarea = document.createElement("textarea");
+  document.body.appendChild(textarea);
+  textarea.focus();
+
+  function stringifyTextChangeNotification(aNotification) {
+    if (!aNotification) {
+      return "{}";
+    }
+    return `{ offset: ${aNotification.offset}, removedLength: ${aNotification.removedLength}, addedLength: ${aNotification.addedLength} }`;
+  }
+
+  const tip =
+    Cc["@mozilla.org/text-input-processor;1"].
+      createInstance(Ci.nsITextInputProcessor);
+  let notifications = [];
+  function callback(aTIP, aNotification) {
+    switch (aNotification.type) {
+      case "request-to-commit":
+        aTIP.commitComposition();
+        break;
+      case "request-to-cancel":
+        aTIP.cancelComposition();
+        break;
+      case "notify-text-change":
+        notifications.push(aNotification);
+        break;
+    }
+    return true;
+  }
+
+  tip.beginInputTransactionForTests(window, callback);
+
+  notifications = [];
+  textarea.appendChild(document.createTextNode("abc"));
+  await new Promise(resolve => requestAnimationFrame(() => requestAnimationFrame(resolve)));
+  is(
+    stringifyTextChangeNotification(notifications[0]),
+    stringifyTextChangeNotification({ offset: 0, removedLength: 0, addedLength: "abc".length }),
+    "Adding text node to empty <textarea> should notify IME of a text change"
+  );
+
+  notifications = [];
+  textarea.firstChild.remove();
+  await new Promise(resolve => requestAnimationFrame(() => requestAnimationFrame(resolve)));
+  is(
+    stringifyTextChangeNotification(notifications[0]),
+    stringifyTextChangeNotification({ offset: 0, removedLength: "abc".length, addedLength: 0 }),
+    "Removing text node from <textarea> should notify IME of a text change"
+  );
+
+  // Update default value during reframes
+  notifications = [];
+  textarea.setAttribute("dir", "rtl");
+  textarea.prepend("abc", document.createElement("marquee"));
+  await new Promise(resolve => requestAnimationFrame(() => requestAnimationFrame(resolve)));
+  is(
+    stringifyTextChangeNotification(notifications[0]),
+    stringifyTextChangeNotification({ offset: 0, removedLength: 0, addedLength: "abc".length }),
+    "Adding text node to empty <textarea> during reframes should notify IME of a text change"
+  );
+
+  notifications = [];
+  textarea.removeAttribute("dir");
+  textarea.innerHTML = "";
+  await new Promise(resolve => requestAnimationFrame(() => requestAnimationFrame(resolve)));
+  is(
+    stringifyTextChangeNotification(notifications[0]),
+    stringifyTextChangeNotification({ offset: 0, removedLength: "abc".length, addedLength: 0 }),
+    "Removing text node from <textarea> during reframes should notify IME of a text change"
+  );
+
+  // Make the textarea dirty
+  textarea.value = "X";
+  await new Promise(resolve => requestAnimationFrame(() => requestAnimationFrame(resolve)));
+
+  notifications = [];
+  textarea.appendChild(document.createTextNode("abc"));
+  await new Promise(resolve => requestAnimationFrame(() => requestAnimationFrame(resolve)));
+  is(
+    textarea.value,
+    "X",
+    "The value should not be updated by adding text node into the dirty <textarea>"
+  );
+  is(
+    stringifyTextChangeNotification(notifications[0]),
+    stringifyTextChangeNotification(undefined),
+    "Adding text node to empty but dirty <textarea> should not notify IME of a text change"
+  );
+
+  SimpleTest.finish();
+});
+</script>
+</head>
+<body></body>
+</html>
diff --git a/dom/base/test/chrome/test_permission_hasValidTransientUserActivation.xhtml b/dom/base/test/chrome/test_permission_hasValidTransientUserActivation.xhtml
new file mode 100644
index 0000000000..89da945588
--- /dev/null
+++ b/dom/base/test/chrome/test_permission_hasValidTransientUserActivation.xhtml
@@ -0,0 +1,93 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>
+<!--
+  Tests that the hasValidTransientUserGestureActivation attribute on permission requests is set correctly.
+-->
+<window title="hasValidTransientUserGestureActivation test" xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
+
+  <body xmlns="http://www.w3.org/1999/xhtml">
+    <iframe id="frame" src="https://example.com/chrome/dom/base/test/chrome/dummy.html" />
+  </body>
+
+  <script type="application/javascript">
+  <![CDATA[
+  const {Integration} = ChromeUtils.importESModule(
+    "resource://gre/modules/Integration.sys.mjs"
+  );
+
+  SimpleTest.waitForExplicitFinish();
+
+  let frame = document.getElementById("frame");
+
+  function checkPermissionRequest(permission, hasValidTransientUserGestureActivation) {
+    return new Promise(function(resolve) {
+      let TestIntegration = (base) => ({
+        __proto__: base,
+        createPermissionPrompt(type, request) {
+          is(type, permission, `Has correct permission type ${permission}.`);
+          is(request.hasValidTransientUserGestureActivation, hasValidTransientUserGestureActivation,
+             "The hasValidTransientUserGestureActivation attribute is set correctly.");
+          Integration.contentPermission.unregister(TestIntegration);
+          resolve();
+          return { prompt() {} };
+        },
+      });
+      Integration.contentPermission.register(TestIntegration);
+    });
+  }
+
+  async function runTest() {
+    await SpecialPowers.setBoolPref("dom.webnotifications.allowcrossoriginiframe", true);
+
+    // Test programmatic request for persistent storage.
+    let request = checkPermissionRequest("persistent-storage", false);
+    navigator.storage.persist();
+    await request;
+
+    // Test user-initiated request for persistent storage.
+    request = checkPermissionRequest("persistent-storage", true);
+    document.notifyUserGestureActivation();
+    navigator.storage.persist();
+    await request;
+    content.document.clearUserGestureActivation();
+
+    // Test programmatic request for geolocation.
+    request = checkPermissionRequest("geolocation", false);
+    navigator.geolocation.getCurrentPosition(() => {});
+    await request;
+
+    // Test user-initiated request for geolocation.
+    request = checkPermissionRequest("geolocation", true);
+    document.notifyUserGestureActivation();
+    navigator.geolocation.getCurrentPosition(() => {});
+    await request;
+    document.clearUserGestureActivation();
+
+    // Notifications need to be tested in an HTTPS frame, because
+    // chrome:// URLs are whitelisted.
+    let frameWin = frame.contentWindow;
+
+    // Test programmatic request for notifications.
+    request = checkPermissionRequest("desktop-notification", false);
+    frameWin.Notification.requestPermission();
+    await request;
+
+    // Test user-initiated request for notifications.
+    request = checkPermissionRequest("desktop-notification", true);
+    frameWin.document.notifyUserGestureActivation();
+    frameWin.Notification.requestPermission();
+    await request;
+    frameWin.document.clearUserGestureActivation();
+
+    await SpecialPowers.clearUserPref("dom.webnotifications.allowcrossoriginiframe");
+  }
+
+  frame.addEventListener("load", function() {
+    runTest().then(() => SimpleTest.finish());
+  });
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_range_getClientRectsAndTexts.html b/dom/base/test/chrome/test_range_getClientRectsAndTexts.html
new file mode 100644
index 0000000000..10eddaf522
--- /dev/null
+++ b/dom/base/test/chrome/test_range_getClientRectsAndTexts.html
@@ -0,0 +1,74 @@
+<html>
+<head>
+<meta charset="utf-8">
+<script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+<link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css" />
+<script>
+"use strict";
+
+SimpleTest.waitForExplicitFinish();
+
+function runTests() {
+  let range = document.createRange();
+
+  let attempts = [
+    {startNode: "one", start: 0, endNode: "one", end: 0, textList: [], message: "Empty rect"},
+    {startNode: "one", start: 2, endNode: "one", end: 6, textList: ["l on"], message: "Single line"},
+    {startNode: "implicit", start: 6, endNode: "implicit", end: 12, textList: ["it bre"], message: "Implicit break"},
+    {startNode: "two.a", start: 1, endNode: "two.b", end: 2, textList: ["wo", "", "li"], message: "Two lines"},
+    {startNode: "embed.a", start: 7, endNode: "embed.b", end: 2, textList: ["th ", "simple nested", " ", "te"], message: "Simple nested"},
+    {startNode: "deep.a", start: 2, endNode: "deep.b", end: 2, textList: ["ne with ", "complex, more deeply nested", " ", "te"], message: "Complex nested"},
+    {startNode: "image.a", start: 7, endNode: "image.b", end: 2, textList: ["th inline ", "", " ", "im"], message: "Inline image"},
+    {startNode: "hyphen1", start: 0, endNode: "hyphen1", end: 3, textList: ["a\u00AD", "b"], message: "Shy hyphen (active)"},
+    {startNode: "hyphen2", start: 0, endNode: "hyphen2", end: 3, textList: ["c\u00ADd"], message: "Shy hyphen (inactive)"},
+    {startNode: "hyphen2", start: 0, endNode: "hyphen2", end: 2, textList: ["c\u00AD"], message: "Shy hyphen (inactive, trailing)"},
+    {startNode: "hyphen2", start: 1, endNode: "hyphen2", end: 3, textList: ["\u00ADd"], message: "Shy hyphen (inactive, leading)"},
+    {startNode: "uc", start: 0, endNode: "uc", end: 2, textList: ["EF"], message: "UC transform"},
+    {startNode: "pre", start: 0, endNode: "pre", end: 3, textList: ["g\n", "h"], message: "pre with break"},
+  ];
+
+  for (let attempt of attempts) {
+    range.setStart(document.getElementById(attempt.startNode).childNodes[0], attempt.start);
+    range.setEnd(document.getElementById(attempt.endNode).childNodes[0], attempt.end);
+
+    let result = range.getClientRectsAndTexts();
+
+    is(result.textList.length, attempt.textList.length, attempt.message + " range has expected number of texts.");
+    let i = 0;
+    for (let text of result.textList) {
+      is(text, attempt.textList[i], attempt.message + " matched text index " + i + ".");
+      i++;
+    }
+  }
+
+  SimpleTest.finish();
+}
+</script>
+</head>
+<body onLoad="runTests()">
+
+<div id="one">All on one line</div>
+
+<div id="implicit">Implicit
+break in one line</div>
+
+<div id="two.a">Two<br/
+><span id="two.b">lines</span></div>
+
+<div id="embed.a">Line with <span>simple nested</span> <span id="embed.b">text</span></div>
+
+<div id="deep.a">Line with <span>complex, <span>more <span>deeply <span>nested</span></span></span></span> <span id="deep.b">text</span></div>
+
+<div id="image.a">Line with inline <img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABQAAAAUCAIAAAAC64paAAAAG0lEQVR42mP8z0A%2BYKJA76jmUc2jmkc1U0EzACKcASfOgGoMAAAAAElFTkSuQmCC" width="20" height="20"/> <span id="image.b">image</span></div>
+
+<div id="hyphen1" style="width:0">a&shy;b</div>
+
+<div id="hyphen2" style="width:100px">c&shy;d</div>
+
+<div id="uc" style="text-transform:uppercase">ef</div>
+
+<pre id="pre">g
+h</pre>
+
+</body>
+</html>
\ No newline at end of file
diff --git a/dom/base/test/chrome/test_swapFrameLoaders.xhtml b/dom/base/test/chrome/test_swapFrameLoaders.xhtml
new file mode 100644
index 0000000000..4ea11a1a62
--- /dev/null
+++ b/dom/base/test/chrome/test_swapFrameLoaders.xhtml
@@ -0,0 +1,25 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1242644
+Test swapFrameLoaders with different frame types and remoteness
+-->
+<window title="Mozilla Bug 1242644"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1242644"
+     target="_blank">Mozilla Bug 1242644</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+  SimpleTest.waitForExplicitFinish();
+
+  window.openDialog("window_swapFrameLoaders.xhtml", "bug1242644",
+                    "chrome,width=600,height=600,noopener", window);
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/test_title.xhtml b/dom/base/test/chrome/test_title.xhtml
new file mode 100644
index 0000000000..33b3fd0220
--- /dev/null
+++ b/dom/base/test/chrome/test_title.xhtml
@@ -0,0 +1,29 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=481777
+-->
+<window title="Mozilla Bug 481777"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=481777"
+     target="_blank">Mozilla Bug 481777</a>
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript">
+  <![CDATA[
+
+  /** Test for Bug 481777 **/
+
+    SimpleTest.waitForExplicitFinish();
+    window.openDialog("title_window.xhtml", "bug481777",
+                      "chrome,width=100,height=100,noopener", window);
+  ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/test_windowroot.xhtml b/dom/base/test/chrome/test_windowroot.xhtml
new file mode 100644
index 0000000000..6f1c29095b
--- /dev/null
+++ b/dom/base/test/chrome/test_windowroot.xhtml
@@ -0,0 +1,18 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<window title="Test window.windowRoot"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+
+  <!-- test results are displayed in the html:body -->
+  <body xmlns="http://www.w3.org/1999/xhtml">
+  </body>
+
+  <!-- test code goes here -->
+  <script type="application/javascript"><![CDATA[
+  var root = window.windowRoot;
+  ok(WindowRoot.isInstance(root), "windowRoot should be a WindowRoot");
+  ]]></script>
+</window>
diff --git a/dom/base/test/chrome/title_window.xhtml b/dom/base/test/chrome/title_window.xhtml
new file mode 100644
index 0000000000..f48cdaaaf1
--- /dev/null
+++ b/dom/base/test/chrome/title_window.xhtml
@@ -0,0 +1,197 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<window title="Mozilla Bug 481777 subwindow"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        onload="runTests()">
+
+  <iframe type="content" id="html1" src="data:text/html,&lt;html&gt;&lt;head&gt;&lt;title id='t'&gt;Test&lt;/title&gt;&lt;/head&gt;&lt;/html&gt;"/>
+  <iframe type="content" id="html2" src="data:text/html,&lt;html&gt;&lt;head&gt;&lt;title id='t'&gt;Test&lt;/title&gt;&lt;title&gt;Foo&lt;/title&gt;&lt;/head&gt;&lt;/html&gt;"/>
+  <iframe type="content" id="html3" src="data:text/html,&lt;html&gt;&lt;/html&gt;"/>
+  <iframe type="content" id="xhtml1" src="data:text/xml,&lt;html xmlns='http://www.w3.org/1999/xhtml'&gt;&lt;body&gt;&lt;title id='t'&gt;Test&lt;/title&gt;&lt;/body&gt;&lt;/html&gt;"/>
+  <iframe type="content" id="xhtml2" src="data:text/xml,&lt;title xmlns='http://www.w3.org/1999/xhtml'&gt;Test&lt;/title&gt;"/>
+  <iframe type="content" id="xhtml3" src="data:text/xml,&lt;title xmlns='http://www.w3.org/1999/xhtml'&gt;Te&lt;div&gt;bogus&lt;/div&gt;st&lt;/title&gt;"/>
+  <iframe type="content" id="xhtml4" src="data:text/xml,&lt;html xmlns='http://www.w3.org/1999/xhtml'/>"/>
+  <iframe type="content" id="xhtml5" src="data:text/xml,&lt;html xmlns='http://www.w3.org/1999/xhtml'&gt;&lt;head/>&lt;/html&gt;"/>
+  <iframe type="content" id="xhtml6" src="data:text/xml,&lt;html xmlns='http://www.w3.org/1999/xhtml'&gt;&lt;head&gt;&lt;style/>&lt;/head&gt;&lt;/html&gt;"/>
+  <iframe id="xul1" src="file_title.xhtml"/>
+  <iframe id="xul2" src="file_title.xhtml"/>
+  <iframe type="content" id="svg1" src="data:text/xml,&lt;svg xmlns='http://www.w3.org/2000/svg'&gt;&lt;title id='t'&gt;Test&lt;/title&gt;&lt;/svg&gt;"/>
+  <iframe type="content" id="svg2" src="data:text/xml,&lt;svg xmlns='http://www.w3.org/2000/svg'&gt;&lt;title id='t'&gt;Test&lt;/title&gt;&lt;/svg&gt;"/>
+
+  <script type="application/javascript">
+    <![CDATA[
+    var imports = [ "SimpleTest", "is", "isnot", "ok" ];
+    for (var name of imports) {
+      window[name] = window.arguments[0][name];
+    }
+
+    function testStatics() {
+      function testStatic(id, expect, description) {
+        is(document.getElementById(id).contentDocument.title, expect, description);
+      }
+
+      testStatic("html1", "Test", "HTML <title>");
+      testStatic("html2", "Test", "choose the first HTML <title>");
+      testStatic("html3", "", "No title");
+      testStatic("xhtml1", "Test", "XHTML <title> in body");
+      testStatic("xhtml2", "Test", "XHTML <title> as root element");
+      testStatic("xhtml3", "Test", "XHTML <title> containing an element");
+      testStatic("xul1", "Test", "XUL <window> title attribute");
+      testStatic("svg1", "Test", "SVG <title>");
+
+      // This one does nothing and won't fire an event
+      document.getElementById("xhtml4").contentDocument.title = "Hello";
+      is(document.getElementById("xhtml4").contentDocument.title, "", "Setting 'title' does nothing with no <head>");
+    }
+
+    function testDynamics() {
+      var inProgress = {};
+      var inProgressDoc = {};
+      var inProgressWin = {};
+      function testDynamic(id, expect, description, op, checkDOM) {
+        inProgress[description] = true;
+        inProgressDoc[description] = true;
+        inProgressWin[description] = true;
+        var frame = document.getElementById(id);
+
+        function listener(ev) {
+          inProgress[description] = false;
+          is(frame.contentDocument.title, expect, "'title': " + description);
+          is(frame.contentDocument, ev.target, "Unexpected target: " + description);
+          if (typeof(checkDOM) != "undefined") {
+            checkDOM(frame.contentDocument, "DOM: " + description);
+          }
+        }
+
+        function listener2(ev) {
+          inProgressDoc[description] = false;
+        }
+        function listener3(ev) {
+          inProgressWin[description] = false;
+        }
+        frame.addEventListener("DOMTitleChanged", listener);
+        frame.contentDocument.addEventListener("DOMTitleChanged", listener2);
+        frame.contentWindow.addEventListener("DOMTitleChanged", listener3);
+
+        op(frame.contentDocument);
+      }
+
+      var dynamicTests = [
+        [ "html1", "Hello", "Setting HTML <title> text contents",
+          function(doc){
+            var t = doc.getElementById("t"); t.textContent = "Hello";
+          } ],
+        [ "html2", "Foo", "Removing HTML <title>",
+          function(doc){
+            var t = doc.getElementById("t"); t.remove();
+          } ],
+        [ "html3", "Hello", "Appending HTML <title> element to root element",
+          function(doc){
+            var t = doc.createElement("title"); t.textContent = "Hello"; doc.documentElement.appendChild(t);
+          } ],
+        [ "xhtml3", "Hello", "Setting 'title' clears existing <title> contents",
+          function(doc){
+            doc.title = "Hello";
+          },
+          function(doc, desc) {
+            is(doc.documentElement.firstChild.data, "Hello", desc);
+            is(doc.documentElement.firstChild.nextSibling, null, desc);
+          } ],
+        [ "xhtml5", "Hello", "Setting 'title' works with a <head>",
+          function(doc){
+            doc.title = "Hello";
+          },
+          function(doc, desc) {
+            var head = doc.documentElement.firstChild;
+            var title = head.firstChild;
+            is(title.tagName.toLowerCase(), "title", desc);
+            is(title.firstChild.data, "Hello", desc);
+            is(title.firstChild.nextSibling, null, desc);
+            is(title.nextSibling, null, desc);
+          } ],
+        [ "xhtml6", "Hello", "Setting 'title' appends to <head>",
+          function(doc){
+            doc.title = "Hello";
+          },
+          function(doc, desc) {
+            var head = doc.documentElement.firstChild;
+            is(head.firstChild.tagName.toLowerCase(), "style", desc);
+            var title = head.firstChild.nextSibling;
+            is(title.tagName.toLowerCase(), "title", desc);
+            is(title.firstChild.data, "Hello", desc);
+            is(title.firstChild.nextSibling, null, desc);
+            is(title.nextSibling, null, desc);
+          } ],
+        [ "xul1", "Hello", "Setting XUL <window> title attribute",
+          function(doc){
+            doc.documentElement.setAttribute("title", "Hello");
+          } ],
+        [ "xul2", "Hello", "Setting 'title' in XUL",
+          function(doc){
+            doc.title = "Hello";
+          },
+          function(doc, desc) {
+            is(doc.documentElement.getAttribute("title"), "Hello", desc);
+            is(doc.documentElement.firstChild, null, desc);
+          } ],
+        [ "svg1", "Hello", "Setting SVG <title> text contents",
+          function(doc){
+            var t = doc.getElementById("t"); t.textContent = "Hello";
+          } ],
+        [ "svg2", "", "Removing SVG <title>",
+          function(doc){
+            var t = doc.getElementById("t"); t.remove();
+          } ] ];
+
+      var titleWindow = window;
+
+      function runIndividualTest(i) {
+        if (i == dynamicTests.length) {
+          // Closing the window will nuke the global properties, since this
+          // function is not really running on this window... or something
+          // like that.  Thanks, executeSoon!
+          var tester = SimpleTest;
+          window.close();
+          tester.finish();
+        } else {
+          var parameters = dynamicTests[i];
+          var testElementId = parameters[0];
+          var testExpectedValue = parameters[1];
+          var testDescription = parameters[2];
+          var testOp = parameters[3];
+          var testCheckDOM = parameters[4];
+
+          function checkTest() {
+            ok(!inProgress[testDescription],
+               testDescription + ": DOMTitleChange not fired");
+            ok(inProgressDoc[testDescription],
+               testDescription + ": DOMTitleChange fired on content document");
+            ok(inProgressWin[testDescription],
+               testDescription + ": DOMTitleChange fired on content window");
+            // Run the next test in the context of the parent XUL window.
+            titleWindow.setTimeout(runIndividualTest, 0, i+1);
+          }
+          function spinEventLoopOp(doc) {
+            // Perform the test's operations.
+            testOp(doc);
+            // Spin the associated window's event loop to ensure we
+            // drain any asynchronous changes and fire associated
+            // events.
+            doc.defaultView.setTimeout(checkTest, 0);
+          }
+
+          testDynamic(testElementId, testExpectedValue, testDescription,
+                      spinEventLoopOp, testCheckDOM);
+        }
+      }
+
+      window.setTimeout(runIndividualTest, 0, 0);
+    }
+
+    function runTests() {
+      testStatics();
+      testDynamics();
+    }
+    ]]>
+  </script>
+</window>
diff --git a/dom/base/test/chrome/window_chromeOuterWindowID.xhtml b/dom/base/test/chrome/window_chromeOuterWindowID.xhtml
new file mode 100644
index 0000000000..268409c1bf
--- /dev/null
+++ b/dom/base/test/chrome/window_chromeOuterWindowID.xhtml
@@ -0,0 +1,14 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1474662
+Test that the chromeOuterWindowID on the MessageManager interface
+works, and that it properly updates when swapping frameloaders between
+windows.
+-->
+<window title="Mozilla Bug 1242644"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <browser id="non-remote" nodefaultsrc="true" type="content" flex="1"/>
+  <browser id="remote" remote="true" nodefaultsrc="true" type="content" flex="1"/>
+</window>
\ No newline at end of file
diff --git a/dom/base/test/chrome/window_nsITextInputProcessor.xhtml b/dom/base/test/chrome/window_nsITextInputProcessor.xhtml
new file mode 100644
index 0000000000..c8ce6ee5e7
--- /dev/null
+++ b/dom/base/test/chrome/window_nsITextInputProcessor.xhtml
@@ -0,0 +1,4874 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<window title="Testing nsITextInputProcessor behavior"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  onunload="onunload();">
+<script src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
+<body  xmlns="http://www.w3.org/1999/xhtml">
+<div id="display">
+<input id="input" type="text"/><input id="anotherInput" type="text"/><br/>
+<textarea></textarea>
+<iframe id="iframe" width="300" height="150"
+        src="data:text/html,&lt;textarea id='textarea' cols='20' rows='4'&gt;&lt;/textarea&gt;"></iframe><br/>
+<div contenteditable=""><br/></div>
+</div>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+</pre>
+</body>
+
+<script class="testbody" type="application/javascript">
+<![CDATA[
+
+var SimpleTest = window.arguments[0].SimpleTest;
+
+SimpleTest.waitForFocus(runTests, window);
+
+function getHTMLEditor(aWindow) {
+  return SpecialPowers.wrap(aWindow).docShell.editingSession?.getEditorForWindow(aWindow);
+}
+
+function ok(aCondition, aMessage)
+{
+  SimpleTest.ok(aCondition, aMessage);
+}
+
+function is(aLeft, aRight, aMessage)
+{
+  SimpleTest.is(aLeft, aRight, aMessage);
+}
+
+function isnot(aLeft, aRight, aMessage)
+{
+  SimpleTest.isnot(aLeft, aRight, aMessage);
+}
+
+function todo_is(aLeft, aRight, aMessage)
+{
+  SimpleTest.todo_is(aLeft, aRight, aMessage);
+}
+
+function info(aMessage) {
+  SimpleTest.info(aMessage);
+}
+
+function finish()
+{
+  window.close();
+}
+
+function onunload()
+{
+  SimpleTest.finish();
+}
+
+function checkInputEvent(aEvent, aCancelable, aIsComposing, aInputType, aData, aDescription) {
+  if (aEvent.type !== "input" && aEvent.type !== "beforeinput") {
+    throw new Error(`${aDescription}"${aEvent.type}" is not InputEvent`);
+  }
+  ok(InputEvent.isInstance(aEvent), `${aDescription}"${aEvent.type}" event should be dispatched with InputEvent interface`);
+  is(aEvent.cancelable, aCancelable, `${aDescription}"${aEvent.type}" event should ${aCancelable ? "be" : "not be"} cancelable`);
+  is(aEvent.bubbles, true, `${aDescription}"${aEvent.type}" event should always bubble`);
+  is(aEvent.isComposing, aIsComposing, `${aDescription}isComposing of "${aEvent.type}" event should be ${aIsComposing}`);
+  is(aEvent.inputType, aInputType, `${aDescription}inputType of "${aEvent.type}" event should be "${aInputType}"`);
+  is(aEvent.data, aData, `${aDescription}data of "${aEvent.type}" event should be "${aData}"`);
+  is(aEvent.dataTransfer, null, `${aDescription}dataTransfer of "${aEvent.type}" event should be null`);
+  is(aEvent.getTargetRanges().length, 0, `${aDescription}getTargetRanges() of "${aEvent.type}" event should return empty array`);
+}
+
+const kIsMac = (navigator.platform.indexOf("Mac") == 0);
+
+const iframe = document.getElementById("iframe");
+let childWindow = iframe.contentWindow;
+let textareaInFrame;
+let input = document.getElementById("input");
+const textarea = document.querySelector("textarea");
+const otherWindow = window.arguments[0];
+const otherDocument = otherWindow.document;
+const inputInChildWindow = otherDocument.getElementById("input");
+const contenteditable = document.querySelector("div[contenteditable]");
+const { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+const kLF = navigator.platform.startsWith("Win") && false ? "\r\n" : "\n";
+function getNativeText(aXPText)
+{
+  if (kLF == "\n") {
+    return aXPText;
+  }
+  return aXPText.replace(/\n/g, kLF);
+}
+
+function createTIP()
+{
+  return Cc["@mozilla.org/text-input-processor;1"].
+           createInstance(Ci.nsITextInputProcessor);
+}
+
+function runBeginInputTransactionMethodTests()
+{
+  var description = "runBeginInputTransactionMethodTests: ";
+  input.value = "";
+  input.focus();
+
+  var simpleCallback = function (aTIP, aNotification)
+  {
+    switch (aNotification.type) {
+      case "request-to-commit":
+        aTIP.commitComposition();
+        break;
+      case "request-to-cancel":
+        aTIP.cancelComposition();
+        break;
+    }
+    return true;
+  };
+
+  var TIP1 = createTIP();
+  var TIP2 = createTIP();
+  isnot(TIP1, TIP2,
+        description + "TIP instances should be different");
+
+  // beginInputTransaction() and beginInputTransactionForTests() can take ownership if there is no composition.
+  ok(TIP1.beginInputTransaction(window, simpleCallback),
+     description + "TIP1.beginInputTransaction(window) should succeed because there is no composition");
+  ok(TIP1.beginInputTransactionForTests(window),
+     description + "TIP1.beginInputTransactionForTests(window) should succeed because there is no composition");
+  ok(TIP2.beginInputTransaction(window, simpleCallback),
+     description + "TIP2.beginInputTransaction(window) should succeed because there is no composition");
+  ok(TIP2.beginInputTransactionForTests(window),
+     description + "TIP2.beginInputTransactionForTests(window) should succeed because there is no composition");
+
+  // Start composition with TIP1, then, other TIPs cannot take ownership during a composition.
+  ok(TIP1.beginInputTransactionForTests(window),
+     description + "TIP1.beginInputTransactionForTests() should succeed because there is no composition");
+  var composingStr = "foo";
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  ok(TIP1.flushPendingComposition(),
+     description + "TIP1.flushPendingComposition() should return true becuase it should be valid composition");
+  is(input.value, composingStr,
+     description + "The input element should have composing string");
+
+  // Composing nsITextInputProcessor instance shouldn't allow initialize it again.
+  try {
+    TIP1.beginInputTransaction(window, simpleCallback);
+    ok(false,
+       "TIP1.beginInputTransaction(window) should cause throwing an exception because it's composing with different purpose");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+       description + "TIP1.beginInputTransaction(window) should cause throwing an exception including NS_ERROR_ALREADY_INITIALIZED because it's composing for tests");
+  }
+  try {
+    TIP1.beginInputTransactionForTests(otherWindow);
+    ok(false,
+       "TIP1.beginInputTransactionForTests(otherWindow) should cause throwing an exception because it's composing on different window");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+       description + "TIP1.beginInputTransaction(otherWindow) should cause throwing an exception including NS_ERROR_ALREADY_INITIALIZED because it's composing on this window");
+  }
+  ok(TIP1.beginInputTransactionForTests(window),
+     description + "TIP1.beginInputTransactionForTests(window) should succeed because TextEventDispatcher was initialized with same purpose");
+  ok(TIP1.beginInputTransactionForTests(childWindow),
+     description + "TIP1.beginInputTransactionForTests(childWindow) should succeed because TextEventDispatcher was initialized with same purpose and is shared by window and childWindow");
+  ok(!TIP2.beginInputTransaction(window, simpleCallback),
+     description + "TIP2.beginInputTransaction(window) should not succeed because there is composition synthesized by TIP1");
+  ok(!TIP2.beginInputTransactionForTests(window),
+     description + "TIP2.beginInputTransactionForTests(window) should not succeed because there is composition synthesized by TIP1");
+  ok(!TIP2.beginInputTransaction(childWindow, simpleCallback),
+     description + "TIP2.beginInputTransaction(childWindow) should not succeed because there is composition synthesized by TIP1");
+  ok(!TIP2.beginInputTransactionForTests(childWindow),
+     description + "TIP2.beginInputTransactionForTests(childWindow) should not succeed because there is composition synthesized by TIP1");
+  ok(TIP2.beginInputTransaction(otherWindow, simpleCallback),
+     description + "TIP2.beginInputTransaction(otherWindow) should succeed because there is composition synthesized by TIP1 but it's in other window");
+  ok(TIP2.beginInputTransactionForTests(otherWindow),
+     description + "TIP2.beginInputTransactionForTests(otherWindow) should succeed because there is composition synthesized by TIP1 but it's in other window");
+
+  // Let's confirm that the composing string is NOT committed by above tests.
+  TIP1.commitComposition();
+  is(input.value, composingStr,
+     description + "TIP1.commitString() without specifying commit string should commit current composition with the last composing string");
+  ok(!TIP1.hasComposition,
+     description + "TIP1.commitString() without specifying commit string should've end composition");
+
+  ok(TIP1.beginInputTransaction(window, simpleCallback),
+     description + "TIP1.beginInputTransaction() should succeed because there is no composition #2");
+  ok(TIP1.beginInputTransactionForTests(window),
+     description + "TIP1.beginInputTransactionForTests() should succeed because there is no composition #2");
+  ok(TIP2.beginInputTransactionForTests(window),
+     description + "TIP2.beginInputTransactionForTests() should succeed because the composition was already committed #2");
+
+  // Let's check if beginInputTransaction() fails to steal the rights of TextEventDispatcher during startComposition().
+  var events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    // eslint-disable-next-line no-caller
+    input.removeEventListener(aEvent.type, arguments.callee);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from compositionstart event handler during TIP1.startComposition();");
+  });
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.startComposition();
+  is(events.length, 1,
+     description + "compositionstart event should be fired by TIP1.startComposition()");
+  TIP1.cancelComposition();
+
+  // Let's check if beginInputTransaction() fails to steal the rights of TextEventDispatcher during flushPendingComposition().
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from compositionstart event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from compositionupdate event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from text event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from beforeinput event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from input event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  is(events.length, 5,
+     description + "compositionstart, compositionupdate, text, beforeinput and input events should be fired by TIP1.flushPendingComposition()");
+  is(events[0].type, "compositionstart",
+     description + "events[0] should be compositionstart");
+  is(events[1].type, "compositionupdate",
+     description + "events[1] should be compositionupdate");
+  is(events[2].type, "text",
+     description + "events[2] should be text");
+  is(events[3].type, "beforeinput",
+     description + "events[3] should be beforeinput");
+  checkInputEvent(events[3], false, true, "insertCompositionText", composingStr, description);
+  is(events[4].type, "input",
+     description + "events[4] should be input");
+  checkInputEvent(events[4], false, true, "insertCompositionText", composingStr, description);
+  TIP1.cancelComposition();
+
+  // Let's check if beginInputTransaction() fails to steal the rights of TextEventDispatcher during commitComposition().
+  events = [];
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from text event handler during a call of TIP1.commitComposition();");
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from compositionend event handler during a call of TIP1.commitComposition();");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from beforeinput event handler during a call of TIP1.commitComposition();");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from input event handler during a call of TIP1.commitComposition();");
+  }, {once: true});
+  TIP1.commitComposition();
+  is(events.length, 4,
+     description + "text, beforeinput, compositionend and input events should be fired by TIP1.commitComposition()");
+  is(events[0].type, "text",
+     description + "events[0] should be text");
+  is(events[1].type, "beforeinput",
+     description + "events[1] should be beforeinput");
+  checkInputEvent(events[1], false, true, "insertCompositionText", composingStr, description);
+  is(events[2].type, "compositionend",
+     description + "events[2] should be compositionend");
+  is(events[3].type, "input",
+     description + "events[3] should be input");
+  checkInputEvent(events[3], false, false, "insertCompositionText", composingStr, description);
+
+  // Let's check if beginInputTransaction() fails to steal the rights of TextEventDispatcher during commitCompositionWith("bar").
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from compositionstart event handler during TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction during compositionupdate event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction during text event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction during compositionend event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction during beforeinput event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction during input event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.commitCompositionWith("bar");
+  is(events.length, 6,
+     description + "compositionstart, compositionupdate, text, beforeinput, compositionend and input events should be fired by TIP1.commitCompositionWith(\"bar\")");
+  is(events[0].type, "compositionstart",
+     description + "events[0] should be compositionstart");
+  is(events[1].type, "compositionupdate",
+     description + "events[1] should be compositionupdate");
+  is(events[2].type, "text",
+     description + "events[2] should be text");
+  is(events[3].type, "beforeinput",
+     description + "events[3] should be beforeinput");
+  checkInputEvent(events[3], false, true, "insertCompositionText", "bar", description);
+  is(events[4].type, "compositionend",
+     description + "events[4] should be compositionend");
+  is(events[5].type, "input",
+     description + "events[5] should be input");
+  checkInputEvent(events[5], false, false, "insertCompositionText", "bar", description);
+
+  // Let's check if beginInputTransaction() fails to steal the rights of TextEventDispatcher during cancelComposition().
+  events = [];
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from compositionupdate event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from text event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from compositionend event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from beforeinput event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from input event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  TIP1.cancelComposition();
+  is(events.length, 5,
+     description + "compositionupdate, text, beforeinput, compositionend and input events should be fired by TIP1.cancelComposition()");
+  is(events[0].type, "compositionupdate",
+     description + "events[0] should be compositionupdate");
+  is(events[1].type, "text",
+     description + "events[1] should be text");
+  is(events[2].type, "beforeinput",
+     description + "events[2] should be beforeinput");
+  checkInputEvent(events[2], false, true, "insertCompositionText", "", description);
+  is(events[3].type, "compositionend",
+     description + "events[3] should be compositionend");
+  is(events[4].type, "input",
+     description + "events[4] should be input");
+  checkInputEvent(events[4], false, false, "insertCompositionText", "", description);
+
+  // Let's check if beginInputTransaction() fails to steal the rights of TextEventDispatcher during keydown() and keyup().
+  events = [];
+  TIP1.beginInputTransaction(window, simpleCallback);
+  input.addEventListener("keydown", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from keydown event handler during a call of TIP1.keydown();");
+  }, {once: true});
+  input.addEventListener("keypress", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from keypress event handler during a call of TIP1.keydown();");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from beforeinput event handler during a call of TIP1.keydown();");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from input event handler during a call of TIP1.keydown();");
+  }, {once: true});
+  input.addEventListener("keyup", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransaction(window, simpleCallback),
+       description + "TIP2 shouldn't be able to begin input transaction from keyup event handler during a call of TIP1.keyup();");
+  }, {once: true});
+  var keyA = new KeyboardEvent("", { key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A });
+  TIP1.keydown(keyA);
+  TIP1.keyup(keyA);
+  is(events.length, 5,
+     description + "keydown, keypress, beforeinput, input, keyup events should be fired by TIP1.keydown() and TIP1.keyup()");
+  is(events[0].type, "keydown",
+     description + "events[0] should be keydown");
+  is(events[1].type, "keypress",
+     description + "events[1] should be keypress");
+  is(events[2].type, "beforeinput",
+     description + "events[2] should be beforeinput");
+  checkInputEvent(events[2], true, false, "insertText", "a", description);
+  is(events[3].type, "input",
+     description + "events[3] should be input");
+  checkInputEvent(events[3], false, false, "insertText", "a", description);
+  is(events[4].type, "keyup",
+     description + "events[4] should be keyup");
+
+  // Let's check if beginInputTransactionForTests() fails to steal the rights of TextEventDispatcher during startComposition().
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    // eslint-disable-next-line no-caller
+    input.removeEventListener(aEvent.type, arguments.callee);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from compositionstart event handler during TIP1.startComposition();");
+  });
+  TIP1.beginInputTransactionForTests(window);
+  TIP1.startComposition();
+  is(events.length, 1,
+     description + "compositionstart event should be fired by TIP1.startComposition()");
+  TIP1.cancelComposition();
+
+  // Let's check if beginInputTransactionForTests() fails to steal the rights of TextEventDispatcher during flushPendingComposition().
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from compositionstart event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from compositionupdate event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from text event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from beforeinput event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from input event handler during a call of TIP1.flushPendingComposition();");
+  }, {once: true});
+  TIP1.beginInputTransactionForTests(window);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  is(events.length, 5,
+     description + "compositionstart, compositionupdate, text, beforeinput and input events should be fired by TIP1.flushPendingComposition()");
+  is(events[0].type, "compositionstart",
+     description + "events[0] should be compositionstart");
+  is(events[1].type, "compositionupdate",
+     description + "events[1] should be compositionupdate");
+  is(events[2].type, "text",
+     description + "events[2] should be text");
+  is(events[3].type, "beforeinput",
+     description + "events[3] should be beforeinput");
+  checkInputEvent(events[3], false, true, "insertCompositionText", composingStr, description);
+  is(events[4].type, "input",
+     description + "events[4] should be input");
+  checkInputEvent(events[4], false, true, "insertCompositionText", composingStr, description);
+  TIP1.cancelComposition();
+
+  // Let's check if beginInputTransactionForTests() fails to steal the rights of TextEventDispatcher during commitComposition().
+  events = [];
+  TIP1.beginInputTransactionForTests(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from text event handler during a call of TIP1.commitComposition();");
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from compositionend event handler during a call of TIP1.commitComposition();");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from beforeinput event handler during a call of TIP1.commitComposition();");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from input event handler during a call of TIP1.commitComposition();");
+  }, {once: true});
+  TIP1.commitComposition();
+  is(events.length, 4,
+     description + "text, beforeinput, compositionend and input events should be fired by TIP1.commitComposition()");
+  is(events[0].type, "text",
+     description + "events[0] should be text");
+  is(events[1].type, "beforeinput",
+     description + "events[1] should be beforeinput");
+  checkInputEvent(events[1], false, true, "insertCompositionText", composingStr, description);
+  is(events[2].type, "compositionend",
+     description + "events[2] should be compositionend");
+  is(events[3].type, "input",
+     description + "events[3] should be input");
+  checkInputEvent(events[3], false, false, "insertCompositionText", composingStr, description);
+
+  // Let's check if beginInputTransactionForTests() fails to steal the rights of TextEventDispatcher during commitCompositionWith("bar").
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from compositionstart event handler during TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests during compositionupdate event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests during text event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests during compositionend event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests during beforeinput event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests during input event handler TIP1.commitCompositionWith(\"bar\");");
+  }, {once: true});
+  TIP1.beginInputTransactionForTests(window);
+  TIP1.commitCompositionWith("bar");
+  is(events.length, 6,
+     description + "compositionstart, compositionupdate, text, beforeinput, compositionend and input events should be fired by TIP1.commitCompositionWith(\"bar\")");
+  is(events[0].type, "compositionstart",
+     description + "events[0] should be compositionstart");
+  is(events[1].type, "compositionupdate",
+     description + "events[1] should be compositionupdate");
+  is(events[2].type, "text",
+     description + "events[2] should be text");
+  is(events[3].type, "beforeinput",
+     description + "events[3] should be beforeinput");
+  checkInputEvent(events[3], false, true, "insertCompositionText", "bar", description);
+  is(events[4].type, "compositionend",
+     description + "events[4] should be compositionend");
+  is(events[5].type, "input",
+     description + "events[5] should be input");
+  checkInputEvent(events[5], false, false, "insertCompositionText", "bar", description);
+
+  // Let's check if beginInputTransactionForTests() fails to steal the rights of TextEventDispatcher during cancelComposition().
+  events = [];
+  TIP1.beginInputTransactionForTests(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from compositionupdate event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from text event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from compositionend event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from beforeinput event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from input event handler during a call of TIP1.cancelComposition();");
+  }, {once: true});
+  TIP1.cancelComposition();
+  is(events.length, 5,
+     description + "compositionupdate, text, beforeinput, compositionend and input events should be fired by TIP1.cancelComposition()");
+  is(events[0].type, "compositionupdate",
+     description + "events[0] should be compositionupdate");
+  is(events[1].type, "text",
+     description + "events[1] should be text");
+  is(events[2].type, "beforeinput",
+     description + "events[2] should be beforeinput");
+  checkInputEvent(events[2], false, true, "insertCompositionText", "", description);
+  is(events[3].type, "compositionend",
+     description + "events[3] should be compositionend");
+  is(events[4].type, "input",
+     description + "events[4] should be input");
+  checkInputEvent(events[4], false, false, "insertCompositionText", "", description);
+
+  // Let's check if beginInputTransactionForTests() fails to steal the rights of TextEventDispatcher during keydown() and keyup().
+  events = [];
+  TIP1.beginInputTransactionForTests(window);
+  input.addEventListener("keydown", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests for tests from keydown event handler during a call of TIP1.keydown();");
+  }, {once: true});
+  input.addEventListener("keypress", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from keypress event handler during a call of TIP1.keydown();");
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from beforeinput event handler during a call of TIP1.keydown();");
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from input event handler during a call of TIP1.keydown();");
+  }, {once: true});
+  input.addEventListener("keyup", function (aEvent) {
+    events.push(aEvent);
+    ok(!TIP2.beginInputTransactionForTests(window),
+       description + "TIP2 shouldn't be able to begin input transaction for tests from keyup event handler during a call of TIP1.keyup();");
+  }, {once: true});
+  keyA = new KeyboardEvent("", { key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A });
+  TIP1.keydown(keyA);
+  TIP1.keyup(keyA);
+  is(events.length, 5,
+     description + "keydown, keypress, beforeinput, input, keyup events should be fired by TIP1.keydown() and TIP1.keyup()");
+  is(events[0].type, "keydown",
+     description + "events[0] should be keydown");
+  is(events[1].type, "keypress",
+     description + "events[1] should be keypress");
+  is(events[2].type, "beforeinput",
+     description + "events[2] should be beforeinput");
+  checkInputEvent(events[2], true, false, "insertText", "a", description);
+  is(events[3].type, "input",
+     description + "events[3] should be input");
+  checkInputEvent(events[3], false, false, "insertText", "a", description);
+  is(events[4].type, "keyup",
+     description + "events[4] should be keyup");
+
+  // Let's check if beginInputTransaction() with another window fails to begin new input transaction with different TextEventDispatcher during startComposition().
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionstart\" should throw an exception during startComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionstart\" should cause NS_ERROR_ALREADY_INITIALIZED during startComposition()");
+    }
+  }, {once: true});
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.startComposition();
+  is(events.length, 1,
+     description + "compositionstart event should be fired by TIP1.startComposition()");
+  TIP1.cancelComposition();
+
+  // Let's check if beginInputTransaction() with another window fails to begin new input transaction with different TextEventDispatcher during flushPendingComposition().
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionstart\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionstart\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionupdate\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionupdate\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"text\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"text\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  is(events.length, 5,
+     description + "compositionstart, compositionupdate, text, beforeinput and input events should be fired by TIP1.flushPendingComposition()");
+  is(events[0].type, "compositionstart",
+     description + "events[0] should be compositionstart");
+  is(events[1].type, "compositionupdate",
+     description + "events[1] should be compositionupdate");
+  is(events[2].type, "text",
+     description + "events[2] should be text");
+  is(events[3].type, "beforeinput",
+     description + "events[3] should be beforeinput");
+  checkInputEvent(events[3], false, true, "insertCompositionText", composingStr, description);
+  is(events[4].type, "input",
+     description + "events[4] should be input");
+  checkInputEvent(events[4], false, true, "insertCompositionText", composingStr, description);
+  TIP1.cancelComposition();
+
+  // Let's check if beginInputTransaction() with another window fails to begin new input transaction with different TextEventDispatcher during commitComposition().
+  events = [];
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"text\" should throw an exception during commitComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"text\" should cause NS_ERROR_ALREADY_INITIALIZED during commitComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionend\" should throw an exception during commitComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionend\" should cause NS_ERROR_ALREADY_INITIALIZED during commitComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during commitComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during commitComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should throw an exception during commitComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during commitComposition()");
+    }
+  }, {once: true});
+  TIP1.commitComposition();
+  is(events.length, 4,
+     description + "text, beforeinput, compositionend and input events should be fired by TIP1.commitComposition()");
+  is(events[0].type, "text",
+     description + "events[0] should be text");
+  is(events[1].type, "beforeinput",
+     description + "events[1] should be beforeinput");
+  checkInputEvent(events[1], false, true, "insertCompositionText", composingStr, description);
+  is(events[2].type, "compositionend",
+     description + "events[2] should be compositionend");
+  is(events[3].type, "input",
+     description + "events[3] should be input");
+  checkInputEvent(events[3], false, false, "insertCompositionText", composingStr, description);
+
+  // Let's check if beginInputTransaction() with another window fails to begin new input transaction with different TextEventDispatcher during commitCompositionWith("bar");.
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionstart\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionstart\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionupdate\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionupdate\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"text\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"text\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionend\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionend\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.commitCompositionWith("bar");
+  is(events.length, 6,
+     description + "compositionstart, compositionupdate, text, beforeinput, compositionend and input events should be fired by TIP1.commitCompositionWith(\"bar\")");
+  is(events[0].type, "compositionstart",
+     description + "events[0] should be compositionstart");
+  is(events[1].type, "compositionupdate",
+     description + "events[1] should be compositionupdate");
+  is(events[2].type, "text",
+     description + "events[2] should be text");
+  is(events[3].type, "beforeinput",
+     description + "events[3] should be beforeinput");
+  checkInputEvent(events[3], false, true, "insertCompositionText", "bar", description);
+  is(events[4].type, "compositionend",
+     description + "events[4] should be compositionend");
+  is(events[5].type, "input",
+     description + "events[5] should be input");
+  checkInputEvent(events[5], false, false, "insertCompositionText", "bar", description);
+
+  // Let's check if beginInputTransaction() with another window fails to begin new input transaction with different TextEventDispatcher during cancelComposition();.
+  events = [];
+  TIP1.beginInputTransaction(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionupdate\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionupdate\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"text\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"text\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionend\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"compositionend\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  TIP1.cancelComposition();
+  is(events.length, 5,
+     description + "compositionupdate, text, beforeinput, compositionend and input events should be fired by TIP1.cancelComposition()");
+  is(events[0].type, "compositionupdate",
+     description + "events[0] should be compositionupdate");
+  is(events[1].type, "text",
+     description + "events[1] should be text");
+  is(events[2].type, "beforeinput",
+     description + "events[2] should be beforeinput");
+  checkInputEvent(events[2], false, true, "insertCompositionText", "", description);
+  is(events[3].type, "compositionend",
+     description + "events[3] should be compositionend");
+  is(events[4].type, "input",
+     description + "events[4] should be input");
+  checkInputEvent(events[4], false, false, "insertCompositionText", "", description);
+
+  // Let's check if beginInputTransaction() with another window fails to begin new input transaction with different TextEventDispatcher during keydown() and keyup();.
+  events = [];
+  TIP1.beginInputTransaction(window, simpleCallback);
+  input.addEventListener("keydown", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"keydown\" should throw an exception during keydown()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"keydown\" should cause NS_ERROR_ALREADY_INITIALIZED during keydown()");
+    }
+  }, {once: true});
+  input.addEventListener("keypress", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"keypress\" should throw an exception during keydown()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"keypress\" should cause NS_ERROR_ALREADY_INITIALIZED during keydown()");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during keydown()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during keydown()");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should throw an exception during keydown()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during keydown()");
+    }
+  }, {once: true});
+  input.addEventListener("keyup", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransaction(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"keyup\" should throw an exception during keyup()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransaction(otherWindow, simpleCallback) called from \"keyup\" should cause NS_ERROR_ALREADY_INITIALIZED during keyup()");
+    }
+  }, {once: true});
+  keyA = new KeyboardEvent("", { key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A });
+  TIP1.keydown(keyA);
+  TIP1.keyup(keyA);
+  is(events.length, 5,
+     description + "keydown, keypress, beforeinput, input, keyup events should be fired by TIP1.keydown() and TIP1.keyup()");
+  is(events[0].type, "keydown",
+     description + "events[0] should be keydown");
+  is(events[1].type, "keypress",
+     description + "events[1] should be keypress");
+  is(events[2].type, "beforeinput",
+     description + "events[2] should be beforeinput");
+  checkInputEvent(events[2], true, false, "insertText", "a", description);
+  is(events[3].type, "input",
+     description + "events[3] should be input");
+  checkInputEvent(events[3], false, false, "insertText", "a", description);
+  is(events[4].type, "keyup",
+     description + "events[4] should be keyup");
+
+  // Let's check if beginInputTransactionForTests() with another window fails to begin new input transaction with different TextEventDispatcher during startComposition().
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionstart\" should throw an exception during startComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionstart\" should cause NS_ERROR_ALREADY_INITIALIZED during startComposition()");
+    }
+  }, {once: true});
+  TIP1.beginInputTransactionForTests(window, simpleCallback);
+  TIP1.startComposition();
+  is(events.length, 1,
+     description + "compositionstart event should be fired by TIP1.startComposition()");
+  TIP1.cancelComposition();
+
+  // Let's check if beginInputTransactionForTests() with another window fails to begin new input transaction with different TextEventDispatcher during flushPendingComposition().
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionstart\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionstart\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionupdate\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionupdate\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"text\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"text\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should throw an exception during flushPendingComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during flushPendingComposition()");
+    }
+  }, {once: true});
+  TIP1.beginInputTransactionForTests(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  is(events.length, 5,
+     description + "compositionstart, compositionupdate, text, beforeinput and input events should be fired by TIP1.flushPendingComposition()");
+  is(events[0].type, "compositionstart",
+     description + "events[0] should be compositionstart");
+  is(events[1].type, "compositionupdate",
+     description + "events[1] should be compositionupdate");
+  is(events[2].type, "text",
+     description + "events[2] should be text");
+  is(events[3].type, "beforeinput",
+     description + "events[3] should be beforeinput");
+  checkInputEvent(events[3], false, true, "insertCompositionText", composingStr, description);
+  is(events[4].type, "input",
+     description + "events[4] should be input");
+  checkInputEvent(events[4], false, true, "insertCompositionText", composingStr, description);
+  TIP1.cancelComposition();
+
+  // Let's check if beginInputTransactionForTests() with another window fails to begin new input transaction with different TextEventDispatcher during commitComposition().
+  events = [];
+  TIP1.beginInputTransactionForTests(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"text\" should throw an exception during commitComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"text\" should cause NS_ERROR_ALREADY_INITIALIZED during commitComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionend\" should throw an exception during commitComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionend\" should cause NS_ERROR_ALREADY_INITIALIZED during commitComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during commitComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during commitComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should throw an exception during commitComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during commitComposition()");
+    }
+  }, {once: true});
+  TIP1.commitComposition();
+  is(events.length, 4,
+     description + "text, beforeinput, compositionend and input events should be fired by TIP1.commitComposition()");
+  is(events[0].type, "text",
+     description + "events[0] should be text");
+  is(events[1].type, "beforeinput",
+     description + "events[1] should be beforeinput");
+  checkInputEvent(events[1], false, true, "insertCompositionText", composingStr, description);
+  is(events[2].type, "compositionend",
+     description + "events[2] should be compositionend");
+  is(events[3].type, "input",
+     description + "events[3] should be input");
+  checkInputEvent(events[3], false, false, "insertCompositionText", composingStr, description);
+
+  // Let's check if beginInputTransactionForTests() with another window fails to begin new input transaction with different TextEventDispatcher during commitCompositionWith("bar");.
+  events = [];
+  input.addEventListener("compositionstart", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionstart\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionstart\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionupdate\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionupdate\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"text\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"text\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionend\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionend\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should throw an exception during commitCompositionWith(\"bar\")");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during commitCompositionWith(\"bar\")");
+    }
+  }, {once: true});
+  TIP1.beginInputTransactionForTests(window, simpleCallback);
+  TIP1.commitCompositionWith("bar");
+  is(events.length, 6,
+     description + "compositionstart, compositionupdate, text, beforeinput, compositionend and input events should be fired by TIP1.commitCompositionWith(\"bar\")");
+  is(events[0].type, "compositionstart",
+     description + "events[0] should be compositionstart");
+  is(events[1].type, "compositionupdate",
+     description + "events[1] should be compositionupdate");
+  is(events[2].type, "text",
+     description + "events[2] should be text");
+  is(events[3].type, "beforeinput",
+     description + "events[3] should be beforeinput");
+  checkInputEvent(events[3], false, true, "insertCompositionText", "bar", description);
+  is(events[4].type, "compositionend",
+     description + "events[4] should be compositionend");
+  is(events[5].type, "input",
+     description + "events[5] should be input");
+  checkInputEvent(events[5], false, false, "insertCompositionText", "bar", description);
+
+  // Let's check if beginInputTransactionForTests() with another window fails to begin new input transaction with different TextEventDispatcher during cancelComposition();.
+  events = [];
+  TIP1.beginInputTransactionForTests(window, simpleCallback);
+  TIP1.setPendingCompositionString(composingStr);
+  TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+  TIP1.flushPendingComposition();
+  input.addEventListener("compositionupdate", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionupdate\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionupdate\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("text", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"text\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"text\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("compositionend", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionend\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"compositionend\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should throw an exception during cancelComposition()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during cancelComposition()");
+    }
+  }, {once: true});
+  TIP1.cancelComposition();
+  is(events.length, 5,
+     description + "compositionupdate, text, beforeinput, compositionend and input events should be fired by TIP1.cancelComposition()");
+  is(events[0].type, "compositionupdate",
+     description + "events[0] should be compositionupdate");
+  is(events[1].type, "text",
+     description + "events[1] should be text");
+  is(events[2].type, "beforeinput",
+     description + "events[2] should be beforeinput");
+  checkInputEvent(events[2], false, true, "insertCompositionText", "", description);
+  is(events[3].type, "compositionend",
+     description + "events[3] should be compositionend");
+  is(events[4].type, "input",
+     description + "events[4] should be input");
+  checkInputEvent(events[4], false, false, "insertCompositionText", "", description);
+
+  // Let's check if beginInputTransactionForTests() with another window fails to begin new input transaction with different TextEventDispatcher during keydown() and keyup();.
+  events = [];
+  TIP1.beginInputTransactionForTests(window, simpleCallback);
+  input.addEventListener("keydown", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"keydown\" should throw an exception during keydown()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"keydown\" should cause NS_ERROR_ALREADY_INITIALIZED during keydown()");
+    }
+  }, {once: true});
+  input.addEventListener("keypress", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"keypress\" should throw an exception during keydown()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"keypress\" should cause NS_ERROR_ALREADY_INITIALIZED during keydown()");
+    }
+  }, {once: true});
+  input.addEventListener("beforeinput", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should throw an exception during keydown()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"beforeinput\" should cause NS_ERROR_ALREADY_INITIALIZED during keydown()");
+    }
+  }, {once: true});
+  input.addEventListener("input", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should throw an exception during keydown()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"input\" should cause NS_ERROR_ALREADY_INITIALIZED during keydown()");
+    }
+  }, {once: true});
+  input.addEventListener("keyup", function (aEvent) {
+    events.push(aEvent);
+    try {
+      TIP1.beginInputTransactionForTests(otherWindow, simpleCallback);
+      ok(false,
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"keyup\" should throw an exception during keyup()");
+    } catch (e) {
+      ok(e.message.includes("NS_ERROR_ALREADY_INITIALIZED"),
+         description + "TIP1.beginInputTransactionForTests(otherWindow, simpleCallback) called from \"keyup\" should cause NS_ERROR_ALREADY_INITIALIZED during keyup()");
+    }
+  }, {once: true});
+  keyA = new KeyboardEvent("", { key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A });
+  TIP1.keydown(keyA);
+  TIP1.keyup(keyA);
+  is(events.length, 5,
+     description + "keydown, keypress, beforeinput, input, keyup events should be fired by TIP1.keydown() and TIP1.keyup()");
+  is(events[0].type, "keydown",
+     description + "events[0] should be keydown");
+  is(events[1].type, "keypress",
+     description + "events[1] should be keypress");
+  is(events[2].type, "beforeinput",
+     description + "events[2] should be beforeinput");
+  checkInputEvent(events[2], true, false, "insertText", "a", description);
+  is(events[3].type, "input",
+     description + "events[3] should be input");
+  checkInputEvent(events[3], false, false, "insertText", "a", description);
+  is(events[4].type, "keyup",
+     description + "events[4] should be keyup");
+
+  // Let's check if startComposition() throws an exception after ownership is stolen.
+  input.value = "";
+  ok(TIP1.beginInputTransactionForTests(window),
+     description + "TIP1.beginInputTransactionForTests() should succeed because there is no composition");
+  ok(TIP2.beginInputTransactionForTests(window),
+     description + "TIP2.beginInputTransactionForTests() should succeed because there is no composition");
+  try {
+    TIP1.startComposition();
+    ok(false,
+       description + "TIP1.startComposition() should cause throwing an exception because TIP2 took the ownership");
+    TIP1.cancelComposition();
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_NOT_INITIALIZED"),
+       description + "TIP1.startComposition() should cause throwing an exception including NS_ERROR_NOT_INITIALIZED");
+  } finally {
+    is(input.value, "",
+       description + "The input element should not have commit string");
+  }
+
+  // Let's check if flushPendingComposition() throws an exception after ownership is stolen.
+  ok(TIP1.beginInputTransactionForTests(window),
+     description + "TIP1.beginInputTransactionForTests() should succeed because there is no composition");
+  ok(TIP2.beginInputTransactionForTests(window),
+     description + "TIP2.beginInputTransactionForTests() should succeed because there is no composition");
+  input.value = "";
+  try {
+    TIP1.setPendingCompositionString(composingStr);
+    TIP1.appendClauseToPendingComposition(composingStr.length, TIP1.ATTR_RAW_CLAUSE);
+    TIP1.flushPendingComposition()
+    ok(false,
+       description + "TIP1.flushPendingComposition() should cause throwing an exception because TIP2 took the ownership");
+    TIP1.cancelComposition();
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_NOT_INITIALIZED"),
+       description + "TIP1.flushPendingComposition() should cause throwing an exception including NS_ERROR_NOT_INITIALIZED");
+  } finally {
+    is(input.value, "",
+       description + "The input element should not have commit string");
+  }
+
+  // Let's check if commitCompositionWith("bar") throws an exception after ownership is stolen.
+  ok(TIP1.beginInputTransactionForTests(window),
+     description + "TIP1.beginInputTransactionForTests() should succeed because there is no composition");
+  ok(TIP2.beginInputTransactionForTests(window),
+     description + "TIP2.beginInputTransactionForTests() should succeed because there is no composition");
+  input.value = "";
+  try {
+    TIP1.commitCompositionWith("bar");
+    ok(false,
+       description + "TIP1.commitCompositionWith(\"bar\") should cause throwing an exception because TIP2 took the ownership");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_NOT_INITIALIZED"),
+       description + "TIP1.commitCompositionWith(\"bar\") should cause throwing an exception including NS_ERROR_NOT_INITIALIZED");
+  } finally {
+    is(input.value, "",
+       description + "The input element should not have commit string");
+  }
+
+  // Let's check if keydown() throws an exception after ownership is stolen.
+  ok(TIP1.beginInputTransactionForTests(window),
+     description + "TIP1.beginInputTransactionForTests() should succeed because there is no composition");
+  ok(TIP2.beginInputTransactionForTests(window),
+     description + "TIP2.beginInputTransactionForTests() should succeed because there is no composition");
+  input.value = "";
+  try {
+    let keyF = new KeyboardEvent("", { key: "f", code: "KeyF", keyCode: KeyboardEvent.DOM_VK_F });
+    TIP1.keydown(keyF);
+    ok(false,
+       description + "TIP1.keydown(keyF) should cause throwing an exception because TIP2 took the ownership");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_NOT_INITIALIZED"),
+       description + "TIP1.keydown(keyF) should cause throwing an exception including NS_ERROR_NOT_INITIALIZED");
+  } finally {
+    is(input.value, "",
+       description + "The input element should not be modified");
+  }
+
+  // Let's check if keyup() throws an exception after ownership is stolen.
+  ok(TIP1.beginInputTransactionForTests(window),
+     description + "TIP1.beginInputTransactionForTests() should succeed because there is no composition");
+  ok(TIP2.beginInputTransactionForTests(window),
+     description + "TIP2.beginInputTransactionForTests() should succeed because there is no composition");
+  input.value = "";
+  try {
+    let keyF = new KeyboardEvent("", { key: "f", code: "KeyF", keyCode: KeyboardEvent.DOM_VK_F });
+    TIP1.keyup(keyF);
+    ok(false,
+       description + "TIP1.keyup(keyF) should cause throwing an exception because TIP2 took the ownership");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_NOT_INITIALIZED"),
+       description + "TIP1.keyup(keyF) should cause throwing an exception including NS_ERROR_NOT_INITIALIZED");
+  } finally {
+    is(input.value, "",
+       description + "The input element should not be modified");
+  }
+
+  // aCallback of nsITextInputProcessor.beginInputTransaction() must not be omitted.
+  try {
+    TIP1.beginInputTransaction(window);
+    ok(false,
+       description + "TIP1.beginInputTransaction(window) should be failed since aCallback is omitted");
+  } catch (e) {
+    ok(e.message.includes("Not enough arguments"),
+       description + "TIP1.beginInputTransaction(window) should cause throwing an exception including \"Not enough arguments\" since aCallback is omitted");
+  }
+
+  // aCallback of nsITextInputProcessor.beginInputTransaction() must not be undefined.
+  try {
+    TIP1.beginInputTransaction(window, undefined);
+    ok(false,
+       description + "TIP1.beginInputTransaction(window, undefined) should be failed since aCallback is undefined");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "TIP1.beginInputTransaction(window, undefined) should cause throwing an exception including NS_ERROR_ILLEGAL_VALUE since aCallback is undefined");
+  }
+
+  // aCallback of nsITextInputProcessor.beginInputTransaction() must not be null.
+  try {
+    TIP1.beginInputTransaction(window, null);
+    ok(false,
+       description + "TIP1.beginInputTransaction(window, null) should be failed since aCallback is null");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "TIP1.beginInputTransaction(window, null) should cause throwing an exception including NS_ERROR_ILLEGAL_VALUE since aCallback is null");
+  }
+}
+
+function runReleaseTests()
+{
+  var description = "runReleaseTests(): ";
+
+  var TIP = createTIP();
+  ok(TIP.beginInputTransactionForTests(window),
+     description + "TIP.beginInputTransactionForTests() should succeed");
+
+  input.value = "";
+  input.focus();
+
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  is(input.value, "foo",
+     description + "the input should have composition string");
+
+  // Release the TIP
+  TIP = null;
+  // Needs to run GC forcibly for testing this.
+  Cu.forceGC();
+
+  is(input.value, "",
+     description + "the input should be empty because the composition should be canceled");
+
+  TIP = createTIP();
+  ok(TIP.beginInputTransactionForTests(window),
+     description + "TIP.beginInputTransactionForTests() should succeed #2");
+}
+
+function runCompositionTests()
+{
+  var description = "runCompositionTests(): ";
+
+  var TIP = createTIP();
+  ok(TIP.beginInputTransactionForTests(window),
+     description + "TIP.beginInputTransactionForTests() should succeed");
+
+  var events;
+
+  function reset()
+  {
+    events = [];
+  }
+
+  function handler(aEvent)
+  {
+    events.push({ "type": aEvent.type, "data": aEvent.data });
+  }
+
+  window.addEventListener("compositionstart", handler);
+  window.addEventListener("compositionupdate", handler);
+  window.addEventListener("compositionend", handler);
+
+  input.value = "";
+  input.focus();
+
+  // nsITextInputProcessor.startComposition()
+  reset();
+  TIP.startComposition();
+  is(events.length, 1,
+     description + "startComposition() should cause only compositionstart");
+  is(events[0].type, "compositionstart",
+     description + "startComposition() should cause only compositionstart");
+  is(input.value, "",
+     description + "startComposition() shouldn't modify the focused editor");
+
+  // Setting composition string "foo" as a raw clause
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+
+  reset();
+  TIP.flushPendingComposition();
+  is(events.length, 1,
+     description + "flushPendingComposition() after startComposition() should cause compositionupdate");
+  is(events[0].type, "compositionupdate",
+     description + "flushPendingComposition() after startComposition() should cause compositionupdate");
+  is(events[0].data, "foo",
+     description + "compositionupdate caused by flushPendingComposition() should have new composition string in its data");
+  is(input.value, "foo",
+     description + "modifying composition string should cause modifying the focused editor");
+
+  // Changing the raw clause to a selected clause
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_SELECTED_CLAUSE);
+
+  reset();
+  TIP.flushPendingComposition();
+  is(events.length, 0,
+     description + "flushPendingComposition() changing only clause information shouldn't cause compositionupdate");
+  is(input.value, "foo",
+     description + "modifying composition clause shouldn't cause modifying the focused editor");
+
+  // Separating the selected clause to two clauses
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(2, TIP.ATTR_SELECTED_CLAUSE);
+  TIP.appendClauseToPendingComposition(1, TIP.ATTR_CONVERTED_CLAUSE);
+  TIP.setCaretInPendingComposition(2);
+
+  reset();
+  TIP.flushPendingComposition();
+  is(events.length, 0,
+     description + "flushPendingComposition() separating a clause information shouldn't cause compositionupdate");
+  is(input.value, "foo",
+     description + "separating composition clause shouldn't cause modifying the focused editor");
+
+  // Modifying the composition string
+  TIP.setPendingCompositionString("FOo");
+  TIP.appendClauseToPendingComposition(2, TIP.ATTR_SELECTED_CLAUSE);
+  TIP.appendClauseToPendingComposition(1, TIP.ATTR_CONVERTED_CLAUSE);
+  TIP.setCaretInPendingComposition(2);
+
+  reset();
+  TIP.flushPendingComposition();
+  is(events.length, 1,
+     description + "flushPendingComposition() causing modifying composition string should cause compositionupdate");
+  is(events[0].type, "compositionupdate",
+     description + "flushPendingComposition() causing modifying composition string should cause compositionupdate");
+  is(events[0].data, "FOo",
+     description + "compositionupdate caused by flushPendingComposition() should have new composition string in its data");
+  is(input.value, "FOo",
+     description + "modifying composition clause shouldn't cause modifying the focused editor");
+
+  // Committing the composition string
+  reset();
+  TIP.commitComposition();
+  is(events.length, 1,
+     description + "commitComposition() should cause compositionend but shouldn't cause compositionupdate");
+  is(events[0].type, "compositionend",
+     description + "commitComposition() should cause compositionend");
+  is(events[0].data, "FOo",
+     description + "compositionend caused by commitComposition() should have the committed string in its data");
+  is(input.value, "FOo",
+     description + "commitComposition() shouldn't cause modifying the focused editor");
+
+  // Starting new composition without a call of startComposition()
+  TIP.setPendingCompositionString("bar");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+
+  reset();
+  TIP.flushPendingComposition();
+  is(events.length, 2,
+     description + "flushPendingComposition() without a call of startComposition() should cause both compositionstart and compositionupdate");
+  is(events[0].type, "compositionstart",
+     description + "flushPendingComposition() without a call of startComposition() should cause compositionstart");
+  is(events[1].type, "compositionupdate",
+     description + "flushPendingComposition() without a call of startComposition() should cause compositionupdate after compositionstart");
+  is(events[1].data, "bar",
+     description + "compositionupdate caused by flushPendingComposition() without a call of startComposition() should have the composition string in its data");
+  is(input.value, "FOobar",
+     description + "new composition string should cause appending composition string to the focused editor");
+
+  // Canceling the composition
+  reset();
+  TIP.cancelComposition();
+  is(events.length, 2,
+     description + "cancelComposition() should cause both compositionupdate and compositionend");
+  is(events[0].type, "compositionupdate",
+     description + "cancelComposition() should cause compositionupdate");
+  is(events[0].data, "",
+     description + "compositionupdate caused by cancelComposition() should have empty string in its data");
+  is(events[1].type, "compositionend",
+     description + "cancelComposition() should cause compositionend after compositionupdate");
+  is(events[1].data, "",
+     description + "compositionend caused by cancelComposition() should have empty string in its data");
+  is(input.value, "FOo",
+     description + "canceled composition string should be removed from the focused editor");
+
+  // Starting composition explicitly and canceling it
+  reset();
+  TIP.startComposition();
+  TIP.cancelComposition();
+  is(events.length, 2,
+     description + "canceling composition immediately after startComposition() should cause compositionstart and compositionend");
+  is(events[0].type, "compositionstart",
+     description + "canceling composition immediately after startComposition() should cause compositionstart first");
+  is(events[1].type, "compositionend",
+     description + "canceling composition immediately after startComposition() should cause compositionend after compositionstart");
+  is(events[1].data, "",
+     description + "compositionend caused by canceling composition should have empty string in its data");
+  is(input.value, "FOo",
+     description + "canceling composition shouldn't modify the focused editor");
+
+  // Create composition for next test.
+  TIP.setPendingCompositionString("bar");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.flushPendingComposition();
+  is(input.value, "FOobar",
+     description + "The focused editor should have new composition string \"bar\"");
+
+  // Allow to set empty composition string
+  reset();
+  TIP.flushPendingComposition();
+  is(events.length, 1,
+     description + "making composition string empty should cause only compositionupdate");
+  is(events[0].type, "compositionupdate",
+     description + "making composition string empty should cause compositionupdate");
+  is(events[0].data, "",
+     description + "compositionupdate caused by making composition string empty should have empty string in its data");
+
+  // Allow to insert new composition string without compositionend/compositionstart
+  TIP.setPendingCompositionString("buzz");
+  TIP.appendClauseToPendingComposition(4, TIP.ATTR_RAW_CLAUSE);
+
+  reset();
+  TIP.flushPendingComposition();
+  is(events.length, 1,
+     description + "modifying composition string from empty string should cause only compositionupdate");
+  is(events[0].type, "compositionupdate",
+     description + "modifying composition string from empty string should cause compositionupdate");
+  is(events[0].data, "buzz",
+     description + "compositionupdate caused by modifying composition string from empty string should have new composition string in its data");
+  is(input.value, "FOobuzz",
+     description + "new composition string should be appended to the focused editor");
+
+  // Committing with different string
+  reset();
+  TIP.commitCompositionWith("bar");
+  is(events.length, 2,
+     description + "committing with different string should cause compositionupdate and compositionend");
+  is(events[0].type, "compositionupdate",
+     description + "committing with different string should cause compositionupdate first");
+  is(events[0].data, "bar",
+     description + "compositionupdate caused by committing with different string should have the committing string in its data");
+  is(events[1].type, "compositionend",
+     description + "committing with different string should cause compositionend after compositionupdate");
+  is(events[1].data, "bar",
+     description + "compositionend caused by committing with different string should have the committing string in its data");
+  is(input.value, "FOobar",
+     description + "new committed string should be appended to the focused editor");
+
+  // Appending new composition string
+  TIP.setPendingCompositionString("buzz");
+  TIP.appendClauseToPendingComposition(4, TIP.ATTR_RAW_CLAUSE);
+  TIP.flushPendingComposition();
+  is(input.value, "FOobarbuzz",
+     description + "new composition string should be appended to the focused editor");
+
+  // Committing with same string
+  reset();
+  TIP.commitCompositionWith("buzz");
+  is(events.length, 1,
+     description + "committing with same string should cause only compositionend");
+  is(events[0].type, "compositionend",
+     description + "committing with same string should cause compositionend");
+  is(events[0].data, "buzz",
+     description + "compositionend caused by committing with same string should have the committing string in its data");
+  is(input.value, "FOobarbuzz",
+     description + "new committed string should be appended to the focused editor");
+
+  // Inserting commit string directly
+  reset();
+  TIP.commitCompositionWith("boo!");
+  is(events.length, 3,
+     description + "committing text directly should cause compositionstart, compositionupdate and compositionend");
+  is(events[0].type, "compositionstart",
+     description + "committing text directly should cause compositionstart first");
+  is(events[1].type, "compositionupdate",
+     description + "committing text directly should cause compositionupdate after compositionstart");
+  is(events[1].data, "boo!",
+     description + "compositionupdate caused by committing text directly should have the committing text in its data");
+  is(events[2].type, "compositionend",
+     description + "committing text directly should cause compositionend after compositionupdate");
+  is(events[2].data, "boo!",
+     description + "compositionend caused by committing text directly should have the committing text in its data");
+  is(input.value, "FOobarbuzzboo!",
+     description + "committing text directly should append the committing text to the focused editor");
+
+  window.removeEventListener("compositionstart", handler);
+  window.removeEventListener("compositionupdate", handler);
+  window.removeEventListener("compositionend", handler);
+}
+
+function runCompositionWithKeyEventTests()
+{
+  var description = "runCompositionWithKeyEventTests(): ";
+
+  var TIP = createTIP();
+  ok(TIP.beginInputTransactionForTests(window),
+     description + "TIP.beginInputTransactionForTests() should succeed");
+
+  var events;
+
+  function reset()
+  {
+    events = [];
+  }
+
+  function handler(aEvent)
+  {
+    events.push(aEvent);
+  }
+
+  window.addEventListener("compositionstart", handler);
+  window.addEventListener("compositionupdate", handler);
+  window.addEventListener("compositionend", handler);
+  window.addEventListener("keydown", handler);
+  window.addEventListener("keypress", handler);
+  window.addEventListener("keyup", handler);
+
+  input.value = "";
+  input.focus();
+
+  var printableKeyEvent = new KeyboardEvent("", { key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A });
+  var enterKeyEvent = new KeyboardEvent("", { key: "Enter", code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN });
+  var escKeyEvent = new KeyboardEvent("", { key: "Escape", code: "Escape", keyCode: KeyboardEvent.DOM_VK_ESCAPE });
+  var convertKeyEvent = new KeyboardEvent("", { key: "Convert", code: "Convert", keyCode: KeyboardEvent.DOM_VK_CONVERT });
+  var backspaceKeyEvent = new KeyboardEvent("", { key: "Backspace", code: "Backspace", keyCode: KeyboardEvent.DOM_VK_BACK_SPACE });
+
+  Services.prefs.setBoolPref("dom.keyboardevent.dispatch_during_composition", false);
+
+  // nsITextInputProcessor.startComposition()
+  reset();
+  TIP.startComposition(printableKeyEvent);
+  is(events.length, 2,
+     description + "startComposition(printableKeyEvent) should cause keydown and compositionstart");
+  is(events[0].type, "keydown",
+     description + "startComposition(printableKeyEvent) should cause keydown");
+  is(events[1].type, "compositionstart",
+     description + "startComposition(printableKeyEvent) should cause compositionstart");
+  is(input.value, "",
+     description + "startComposition(printableKeyEvent) shouldn't modify the focused editor");
+
+  // Setting composition string "foo" as a raw clause
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+
+  reset();
+  TIP.flushPendingComposition(printableKeyEvent);
+  is(events.length, 1,
+     description + "flushPendingComposition(KeyupInternal) after startComposition() should cause compositionupdate");
+  is(events[0].type, "compositionupdate",
+     description + "flushPendingComposition(KeyupInternal) after startComposition() should cause compositionupdate");
+  is(events[0].data, "foo",
+     description + "compositionupdate caused by flushPendingComposition(KeyupInternal) should have new composition string in its data");
+  is(input.value, "foo",
+     description + "modifying composition string should cause modifying the focused editor");
+
+  // Changing the raw clause to a selected clause
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_SELECTED_CLAUSE);
+
+  reset();
+  TIP.flushPendingComposition(convertKeyEvent);
+  is(events.length, 0,
+     description + "flushPendingComposition(convertKeyEvent) changing only clause information shouldn't cause compositionupdate");
+  is(input.value, "foo",
+     description + "modifying composition clause shouldn't cause modifying the focused editor");
+
+  // Separating the selected clause to two clauses
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(2, TIP.ATTR_SELECTED_CLAUSE);
+  TIP.appendClauseToPendingComposition(1, TIP.ATTR_CONVERTED_CLAUSE);
+  TIP.setCaretInPendingComposition(2);
+
+  reset();
+  TIP.flushPendingComposition(convertKeyEvent);
+  is(events.length, 0,
+     description + "flushPendingComposition(convertKeyEvent) separating a clause information shouldn't cause compositionupdate");
+  is(input.value, "foo",
+     description + "separating composition clause shouldn't cause modifying the focused editor");
+
+  // Modifying the composition string
+  TIP.setPendingCompositionString("FOo");
+  TIP.appendClauseToPendingComposition(2, TIP.ATTR_SELECTED_CLAUSE);
+  TIP.appendClauseToPendingComposition(1, TIP.ATTR_CONVERTED_CLAUSE);
+  TIP.setCaretInPendingComposition(2);
+
+  reset();
+  TIP.flushPendingComposition(convertKeyEvent);
+  is(events.length, 1,
+     description + "flushPendingComposition(convertKeyEvent) causing modifying composition string should cause compositionupdate");
+  is(events[0].type, "compositionupdate",
+     description + "flushPendingComposition(convertKeyEvent) causing modifying composition string should cause compositionupdate");
+  is(events[0].data, "FOo",
+     description + "compositionupdate caused by flushPendingComposition(convertKeyEvent) should have new composition string in its data");
+  is(input.value, "FOo",
+     description + "modifying composition clause shouldn't cause modifying the focused editor");
+
+  // Committing the composition string
+  reset();
+  TIP.commitComposition(enterKeyEvent);
+  is(events.length, 2,
+     description + "commitComposition(enterKeyEvent) should cause compositionend and keyup but shoudn't cause compositionupdate");
+  is(events[0].type, "compositionend",
+     description + "commitComposition(enterKeyEvent) should cause compositionend");
+  is(events[0].data, "FOo",
+     description + "compositionend caused by commitComposition(enterKeyEvent) should have the committed string in its data");
+  is(events[1].type, "keyup",
+     description + "commitComposition(enterKeyEvent) should cause keyup");
+  is(input.value, "FOo",
+     description + "commitComposition(enterKeyEvent) shouldn't cause modifying the focused editor");
+
+  // Starting new composition without a call of startComposition()
+  TIP.setPendingCompositionString("bar");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+
+  reset();
+  TIP.flushPendingComposition(printableKeyEvent);
+  is(events.length, 3,
+     description + "flushPendingComposition(printableKeyEvent) without a call of startComposition() should cause both compositionstart and compositionupdate");
+  is(events[0].type, "keydown",
+     description + "flushPendingComposition(printableKeyEvent) without a call of startComposition() should cause keydown");
+  is(events[1].type, "compositionstart",
+     description + "flushPendingComposition(printableKeyEvent) without a call of startComposition() should cause compositionstart");
+  is(events[2].type, "compositionupdate",
+     description + "flushPendingComposition(printableKeyEvent) without a call of startComposition() should cause compositionupdate after compositionstart");
+  is(events[2].data, "bar",
+     description + "compositionupdate caused by flushPendingComposition(printableKeyEvent) without a call of startComposition() should have the composition string in its data");
+  is(input.value, "FOobar",
+     description + "new composition string should cause appending composition string to the focused editor");
+
+  // Canceling the composition
+  reset();
+  TIP.cancelComposition(escKeyEvent);
+  is(events.length, 3,
+     description + "cancelComposition(escKeyEvent) should cause both compositionupdate and compositionend");
+  is(events[0].type, "compositionupdate",
+     description + "cancelComposition(escKeyEvent) should cause compositionupdate");
+  is(events[0].data, "",
+     description + "compositionupdate caused by cancelComposition(escKeyEvent) should have empty string in its data");
+  is(events[1].type, "compositionend",
+     description + "cancelComposition(escKeyEvent) should cause compositionend after compositionupdate");
+  is(events[1].data, "",
+     description + "compositionend caused by cancelComposition(escKeyEvent) should have empty string in its data");
+  is(events[2].type, "keyup",
+     description + "cancelComposition(escKeyEvent) should cause keyup after compositionend");
+  is(input.value, "FOo",
+     description + "canceled composition string should be removed from the focused editor");
+
+  // Starting composition explicitly and canceling it
+  reset();
+  TIP.startComposition(printableKeyEvent);
+  TIP.cancelComposition(escKeyEvent);
+  is(events.length, 4,
+     description + "canceling composition immediately after startComposition() should cause keydown, compositionstart, compositionend and keyup");
+  is(events[0].type, "keydown",
+     description + "canceling composition immediately after startComposition() should cause keydown first");
+  is(events[1].type, "compositionstart",
+     description + "canceling composition immediately after startComposition() should cause compositionstart after keydown");
+  is(events[2].type, "compositionend",
+     description + "canceling composition immediately after startComposition() should cause compositionend after compositionstart");
+  is(events[2].data, "",
+     description + "compositionend caused by canceling composition should have empty string in its data");
+  is(events[3].type, "keyup",
+     description + "canceling composition immediately after startComposition() should cause keyup after compositionend");
+  is(input.value, "FOo",
+     description + "canceling composition shouldn't modify the focused editor");
+
+  // Create composition for next test.
+  TIP.setPendingCompositionString("bar");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.flushPendingComposition();
+  is(input.value, "FOobar",
+     description + "The focused editor should have new composition string \"bar\"");
+
+  // Allow to set empty composition string
+  reset();
+  TIP.flushPendingComposition(backspaceKeyEvent);
+  is(events.length, 1,
+     description + "making composition string empty should cause only compositionupdate");
+  is(events[0].type, "compositionupdate",
+     description + "making composition string empty should cause compositionupdate");
+  is(events[0].data, "",
+     description + "compositionupdate caused by making composition string empty should have empty string in its data");
+
+  // Allow to insert new composition string without compositionend/compositionstart
+  TIP.setPendingCompositionString("buzz");
+  TIP.appendClauseToPendingComposition(4, TIP.ATTR_RAW_CLAUSE);
+
+  reset();
+  TIP.flushPendingComposition(printableKeyEvent);
+  is(events.length, 1,
+     description + "modifying composition string from empty string should cause only compositionupdate");
+  is(events[0].type, "compositionupdate",
+     description + "modifying composition string from empty string should cause compositionupdate");
+  is(events[0].data, "buzz",
+     description + "compositionupdate caused by modifying composition string from empty string should have new composition string in its data");
+  is(input.value, "FOobuzz",
+     description + "new composition string should be appended to the focused editor");
+
+  // Committing with different string
+  reset();
+  TIP.commitCompositionWith("bar", printableKeyEvent);
+  is(events.length, 3,
+     description + "committing with different string should cause compositionupdate and compositionend");
+  is(events[0].type, "compositionupdate",
+     description + "committing with different string should cause compositionupdate first");
+  is(events[0].data, "bar",
+     description + "compositionupdate caused by committing with different string should have the committing string in its data");
+  is(events[1].type, "compositionend",
+     description + "committing with different string should cause compositionend after compositionupdate");
+  is(events[1].data, "bar",
+     description + "compositionend caused by committing with different string should have the committing string in its data");
+  is(events[2].type, "keyup",
+     description + "committing with different string should cause keyup after compositionend");
+  is(input.value, "FOobar",
+     description + "new committed string should be appended to the focused editor");
+
+  // Appending new composition string
+  TIP.setPendingCompositionString("buzz");
+  TIP.appendClauseToPendingComposition(4, TIP.ATTR_RAW_CLAUSE);
+  TIP.flushPendingComposition();
+  is(input.value, "FOobarbuzz",
+     description + "new composition string should be appended to the focused editor");
+
+  // Committing with same string
+  reset();
+  TIP.commitCompositionWith("buzz", enterKeyEvent);
+  is(events.length, 2,
+     description + "committing with same string should cause only compositionend");
+  is(events[0].type, "compositionend",
+     description + "committing with same string should cause compositionend");
+  is(events[0].data, "buzz",
+     description + "compositionend caused by committing with same string should have the committing string in its data");
+  is(events[1].type, "keyup",
+     description + "committing with same string should cause keyup after compositionend");
+  is(input.value, "FOobarbuzz",
+     description + "new committed string should be appended to the focused editor");
+
+  // Inserting commit string directly
+  reset();
+  TIP.commitCompositionWith("boo!", printableKeyEvent);
+  is(events.length, 5,
+     description + "committing text directly should cause compositionstart, compositionupdate and compositionend");
+  is(events[0].type, "keydown",
+     description + "committing text directly should cause keydown first");
+  is(events[1].type, "compositionstart",
+     description + "committing text directly should cause compositionstart after keydown");
+  is(events[2].type, "compositionupdate",
+     description + "committing text directly should cause compositionupdate after compositionstart");
+  is(events[2].data, "boo!",
+     description + "compositionupdate caused by committing text directly should have the committing text in its data");
+  is(events[3].type, "compositionend",
+     description + "committing text directly should cause compositionend after compositionupdate");
+  is(events[3].data, "boo!",
+     description + "compositionend caused by committing text directly should have the committing text in its data");
+  is(events[4].type, "keyup",
+     description + "committing text directly should cause keyup after compositionend");
+  is(input.value, "FOobarbuzzboo!",
+     description + "committing text directly should append the committing text to the focused editor");
+
+  Services.prefs.setBoolPref("dom.keyboardevent.dispatch_during_composition", true);
+
+  // Even if "dom.keyboardevent.dispatch_during_composition" is true, keypress event shouldn't be fired during composition
+  reset();
+  TIP.startComposition(printableKeyEvent);
+  is(events.length, 3,
+     description + "TIP.startComposition(printableKeyEvent) should cause keydown, compositionstart and keyup (keypress event shouldn't be fired during composition)");
+  is(events[0].type, "keydown",
+     description + "TIP.startComposition(printableKeyEvent) should cause keydown (keypress event shouldn't be fired during composition)");
+  is(events[1].type, "compositionstart",
+     description + "TIP.startComposition(printableKeyEvent) should cause compositionstart (keypress event shouldn't be fired during composition)");
+  is(events[2].type, "keyup",
+     description + "TIP.startComposition(printableKeyEvent) should cause keyup (keypress event shouldn't be fired during composition)");
+
+  // TIP.flushPendingComposition(printableKeyEvent) should cause keydown and keyup events if "dom.keyboardevent.dispatch_during_composition" is true
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+
+  reset();
+  TIP.flushPendingComposition(printableKeyEvent);
+  is(events.length, 3,
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause keydown, compositionupdate and keyup (keypress event shouldn't be fired during composition)");
+  is(events[0].type, "keydown",
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause keydown (keypress event shouldn't be fired during composition)");
+  is(events[1].type, "compositionupdate",
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause compositionupdate (keypress event shouldn't be fired during composition)");
+  is(events[2].type, "keyup",
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause keyup (keypress event shouldn't be fired during composition)");
+
+  // TIP.commitComposition(enterKeyEvent) should cause keydown and keyup events if "dom.keyboardevent.dispatch_during_composition" is true
+  reset();
+  TIP.commitComposition(enterKeyEvent);
+  is(events.length, 3,
+     description + "TIP.commitComposition(enterKeyEvent) should cause keydown, compositionend and keyup (keypress event shouldn't be fired during composition)");
+  is(events[0].type, "keydown",
+     description + "TIP.commitComposition(enterKeyEvent) should cause keydown (keypress event shouldn't be fired during composition)");
+  is(events[1].type, "compositionend",
+     description + "TIP.commitComposition(enterKeyEvent) should cause compositionend (keypress event shouldn't be fired during composition)");
+  is(events[2].type, "keyup",
+     description + "TIP.commitComposition(enterKeyEvent) should cause keyup (keypress event shouldn't be fired during composition)");
+
+  // TIP.cancelComposition(escKeyEvent) should cause keydown and keyup events if "dom.keyboardevent.dispatch_during_composition" is true
+  TIP.startComposition();
+  reset();
+  TIP.cancelComposition(escKeyEvent);
+  is(events.length, 3,
+     description + "TIP.cancelComposition(escKeyEvent) should cause keydown, compositionend and keyup (keypress event shouldn't be fired during composition)");
+  is(events[0].type, "keydown",
+     description + "TIP.cancelComposition(escKeyEvent) should cause keydown (keypress event shouldn't be fired during composition)");
+  is(events[1].type, "compositionend",
+     description + "TIP.cancelComposition(escKeyEvent) should cause compositionend (keypress event shouldn't be fired during composition)");
+  is(events[2].type, "keyup",
+     description + "TIP.cancelComposition(escKeyEvent) should cause keyup (keypress event shouldn't be fired during composition)");
+
+  var printableKeydownEvent = new KeyboardEvent("keydown", { key: "b", code: "KeyB", keyCode: KeyboardEvent.DOM_VK_B });
+  var enterKeydownEvent = new KeyboardEvent("keydown", { key: "Enter", code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN });
+  var escKeydownEvent = new KeyboardEvent("keydown", { key: "Escape", code: "Escape", keyCode: KeyboardEvent.DOM_VK_ESCAPE });
+
+  // TIP.startComposition(printableKeydownEvent) shouldn't cause keyup event even if "dom.keyboardevent.dispatch_during_composition" is true
+  reset();
+  TIP.startComposition(printableKeydownEvent);
+  is(events.length, 2,
+     description + "TIP.startComposition(printableKeydownEvent) should cause keydown and compositionstart (keyup event shouldn't be fired)");
+  is(events[0].type, "keydown",
+     description + "TIP.startComposition(printableKeydownEvent) should cause keydown (keyup event shouldn't be fired)");
+  is(events[1].type, "compositionstart",
+     description + "TIP.startComposition(printableKeydownEvent) should cause compositionstart (keyup event shouldn't be fired)");
+
+  // TIP.flushPendingComposition(printableKeydownEvent) shouldn't cause keyup event even if "dom.keyboardevent.dispatch_during_composition" is true
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+
+  reset();
+  TIP.flushPendingComposition(printableKeydownEvent);
+  is(events.length, 2,
+     description + "TIP.flushPendingComposition(printableKeydownEvent) should cause keydown and compositionupdate (keyup event shouldn't be fired)");
+  is(events[0].type, "keydown",
+     description + "TIP.flushPendingComposition(printableKeydownEvent) should cause keydown (keyup event shouldn't be fired)");
+  is(events[1].type, "compositionupdate",
+     description + "TIP.flushPendingComposition(printableKeydownEvent) should cause compositionupdate (keyup event shouldn't be fired)");
+
+  // TIP.commitComposition(enterKeydownEvent) shouldn't cause keyup event even if "dom.keyboardevent.dispatch_during_composition" is true
+  reset();
+  TIP.commitComposition(enterKeydownEvent);
+  is(events.length, 2,
+     description + "TIP.commitComposition(enterKeydownEvent) should cause keydown and compositionend (keyup event shouldn't be fired)");
+  is(events[0].type, "keydown",
+     description + "TIP.commitComposition(enterKeydownEvent) should cause keydown (keyup event shouldn't be fired)");
+  is(events[1].type, "compositionend",
+     description + "TIP.commitComposition(enterKeydownEvent) should cause compositionend (keyup event shouldn't be fired)");
+
+  // TIP.cancelComposition(escKeydownEvent) shouldn't cause keyup event even if "dom.keyboardevent.dispatch_during_composition" is true
+  TIP.startComposition();
+  reset();
+  TIP.cancelComposition(escKeydownEvent);
+  is(events.length, 2,
+     description + "TIP.cancelComposition(escKeydownEvent) should cause keydown and compositionend (keyup event shouldn't be fired)");
+  is(events[0].type, "keydown",
+     description + "TIP.cancelComposition(escKeydownEvent) should cause keydown (keyup event shouldn't be fired)");
+  is(events[1].type, "compositionend",
+     description + "TIP.cancelComposition(escKeydownEvent) should cause compositionend (keyup event shouldn't be fired)");
+
+  Services.prefs.clearUserPref("dom.keyboardevent.dispatch_during_composition");
+
+  window.removeEventListener("compositionstart", handler);
+  window.removeEventListener("compositionupdate", handler);
+  window.removeEventListener("compositionend", handler);
+  window.removeEventListener("keydown", handler);
+  window.removeEventListener("keypress", handler);
+  window.removeEventListener("keyup", handler);
+}
+
+function runConsumingKeydownBeforeCompositionTests()
+{
+  var description = "runConsumingKeydownBeforeCompositionTests(): ";
+
+  var TIP = createTIP();
+  ok(TIP.beginInputTransactionForTests(window),
+     description + "TIP.beginInputTransactionForTests() should succeed");
+
+  var events;
+
+  function reset()
+  {
+    events = [];
+  }
+
+  function handler(aEvent)
+  {
+    events.push(aEvent);
+    if (aEvent.type == "keydown") {
+      aEvent.preventDefault();
+    }
+  }
+
+  window.addEventListener("compositionstart", handler);
+  window.addEventListener("compositionupdate", handler);
+  window.addEventListener("compositionend", handler);
+  window.addEventListener("keydown", handler);
+  window.addEventListener("keypress", handler);
+  window.addEventListener("keyup", handler);
+
+  input.value = "";
+  input.focus();
+
+  var printableKeyEvent = new KeyboardEvent("", { key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A });
+  var enterKeyEvent = new KeyboardEvent("", { key: "Enter", code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN });
+  var escKeyEvent = new KeyboardEvent("", { key: "Escape", code: "Escape", keyCode: KeyboardEvent.DOM_VK_ESCAPE });
+
+  Services.prefs.setBoolPref("dom.keyboardevent.dispatch_during_composition", false);
+
+  // If keydown before compositionstart is consumed, composition shouldn't be started.
+  reset();
+  ok(!TIP.startComposition(printableKeyEvent),
+     description + "TIP.startComposition(printableKeyEvent) should return false because it's keydown is consumed");
+  is(events.length, 2,
+     description + "TIP.startComposition(printableKeyEvent) should cause only keydown and keyup events");
+  is(events[0].type, "keydown",
+     description + "TIP.startComposition(printableKeyEvent) should cause keydown event first");
+  is(events[1].type, "keyup",
+     description + "TIP.startComposition(printableKeyEvent) should cause keyup event after keydown");
+  ok(!TIP.hasComposition,
+     description + "TIP.startComposition(printableKeyEvent) shouldn't cause composition");
+  is(input.value, "",
+     description + "TIP.startComposition(printableKeyEvent) shouldn't cause inserting text");
+
+  // If keydown before compositionstart caused by flushPendingComposition(printableKeyEvent) is consumed, composition shouldn't be started.
+  reset();
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  ok(!TIP.flushPendingComposition(printableKeyEvent),
+     description + "TIP.flushPendingComposition(printableKeyEvent) should return false because it's keydown is consumed");
+  is(events.length, 2,
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause only keydown and keyup events");
+  is(events[0].type, "keydown",
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause keydown event first");
+  is(events[1].type, "keyup",
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause keyup event after keydown");
+  ok(!TIP.hasComposition,
+     description + "TIP.flushPendingComposition(printableKeyEvent) shouldn't cause composition");
+  is(input.value, "",
+     description + "TIP.flushPendingComposition(printableKeyEvent) shouldn't cause inserting text");
+
+  // If keydown before compositionstart is consumed, composition shouldn't be started.
+  reset();
+  ok(!TIP.commitCompositionWith("foo", printableKeyEvent),
+     description + "TIP.commitCompositionWith(\"foo\", printableKeyEvent) should return false because it's keydown is consumed");
+  is(events.length, 2,
+     description + "TIP.commitCompositionWith(\"foo\", printableKeyEvent) should cause only keydown and keyup events");
+  is(events[0].type, "keydown",
+     description + "TIP.commitCompositionWith(\"foo\", printableKeyEvent) should cause keydown event first");
+  is(events[1].type, "keyup",
+     description + "TIP.commitCompositionWith(\"foo\", printableKeyEvent) should cause keyup event after keydown");
+  ok(!TIP.hasComposition,
+     description + "TIP.commitCompositionWith(\"foo\", printableKeyEvent) shouldn't cause composition");
+  is(input.value, "",
+     description + "TIP.commitCompositionWith(\"foo\", printableKeyEvent) shouldn't cause inserting text");
+
+  Services.prefs.setBoolPref("dom.keyboardevent.dispatch_during_composition", true);
+
+  // If composition is already started, TIP.flushPendingComposition(printableKeyEvent) shouldn't be canceled.
+  TIP.startComposition();
+  ok(TIP.hasComposition,
+     description + "Before TIP.flushPendingComposition(printableKeyEvent), composition should've been created");
+  reset();
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  ok(TIP.flushPendingComposition(printableKeyEvent),
+     description + "TIP.flushPendingComposition(printableKeyEvent) should return true even if preceding keydown is consumed because there was a composition already");
+  is(events.length, 3,
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause only keydown and keyup events");
+  is(events[0].type, "keydown",
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause keydown event first");
+  is(events[1].type, "compositionupdate",
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause compositionupdate event after keydown");
+  is(events[2].type, "keyup",
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause keyup event after compositionupdate");
+  ok(TIP.hasComposition,
+     description + "TIP.flushPendingComposition(printableKeyEvent) shouldn't cause canceling composition");
+  is(input.value, "foo",
+     description + "TIP.flushPendingComposition(printableKeyEvent) should cause inserting text even if preceding keydown is consumed because there was a composition already");
+
+  // If composition is already started, TIP.commitComposition(enterKeyEvent) shouldn't be canceled.
+  reset();
+  TIP.commitComposition(enterKeyEvent);
+  is(events.length, 3,
+     description + "TIP.commitComposition(enterKeyEvent) should cause keydown, compositionend and keyup events");
+  is(events[0].type, "keydown",
+     description + "TIP.commitComposition(enterKeyEvent) should cause keydown event first");
+  is(events[1].type, "compositionend",
+     description + "TIP.commitComposition(enterKeyEvent) should cause compositionend event after keydown");
+  is(events[2].type, "keyup",
+     description + "TIP.commitComposition(enterKeyEvent) should cause keyup event after compositionend");
+  ok(!TIP.hasComposition,
+     description + "TIP.commitComposition(enterKeyEvent) should cause committing composition even if preceding keydown is consumed because there was a composition already");
+  is(input.value, "foo",
+     description + "TIP.commitComposition(enterKeyEvent) should commit composition even if preceding keydown is consumed because there was a composition already");
+
+  // cancelComposition() should work even if preceding keydown event is consumed.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  ok(TIP.hasComposition,
+     description + "Before TIP.cancelComposition(escKeyEvent), composition should've been created");
+  is(input.value, "foo",
+     description + "Before TIP.cancelComposition(escKeyEvent) should have composition string");
+  reset();
+  TIP.cancelComposition(escKeyEvent);
+  is(events.length, 4,
+     description + "TIP.cancelComposition(escKeyEvent) should cause keydown, compositionupdate, compositionend and keyup events even if preceding keydown is consumed because there was a composition already");
+  is(events[0].type, "keydown",
+     description + "TIP.cancelComposition(escKeyEvent) should cause keydown event first");
+  is(events[1].type, "compositionupdate",
+     description + "TIP.cancelComposition(escKeyEvent) should cause compositionupdate event after keydown");
+  is(events[2].type, "compositionend",
+     description + "TIP.cancelComposition(escKeyEvent) should cause compositionend event after compositionupdate");
+  is(events[3].type, "keyup",
+     description + "TIP.cancelComposition(escKeyEvent) should cause keyup event after compositionend");
+  ok(!TIP.hasComposition,
+     description + "TIP.cancelComposition(escKeyEvent) should cause canceling composition even if preceding keydown is consumed because there was a composition already");
+  is(input.value, "",
+     description + "TIP.cancelComposition(escKeyEvent) should cancel composition even if preceding keydown is consumed because there was a composition already");
+
+  Services.prefs.clearUserPref("dom.keyboardevent.dispatch_during_composition");
+
+  window.removeEventListener("compositionstart", handler);
+  window.removeEventListener("compositionupdate", handler);
+  window.removeEventListener("compositionend", handler);
+  window.removeEventListener("keydown", handler);
+  window.removeEventListener("keypress", handler);
+  window.removeEventListener("keyup", handler);
+}
+
+async function runKeyTests()
+{
+  var description = "runKeyTests(): ";
+  const kModifiers =
+    [ "Alt", "AltGraph", "CapsLock", "Control", "Fn", "FnLock", "Meta", "NumLock",
+      "ScrollLock", "Shift", "Symbol", "SymbolLock", "OS" ];
+
+  var TIP = createTIP();
+  ok(TIP.beginInputTransactionForTests(window),
+     description + "TIP.beginInputTransactionForTests() should succeed");
+
+  var events;
+  var doPreventDefaults;
+
+  function reset()
+  {
+    events = [];
+    doPreventDefaults = [];
+  }
+
+  function handler(aEvent)
+  {
+    events.push(aEvent);
+    if (doPreventDefaults.includes(aEvent.type)) {
+      aEvent.preventDefault();
+    }
+  }
+
+  function checkKeyAttrs(aMethodDescription, aEvent, aExpectedData)
+  {
+    var desc = description + aMethodDescription + ", type=\"" + aEvent.type + "\", key=\"" + aEvent.key + "\", code=\"" + aEvent.code + "\": ";
+    var defaultValues = {
+      key: "Unidentified", code: "", keyCode: 0, charCode: 0,
+      location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD, repeat: false, isComposing: false,
+      shiftKey: false, ctrlKey: false, altKey: false, metaKey: false,
+      defaultPrevented: false
+    };
+    function expectedValue(aAttr)
+    {
+      return aExpectedData[aAttr] !== undefined ? aExpectedData[aAttr] : defaultValues[aAttr];
+    }
+    is(aEvent.type, aExpectedData.type,
+       desc + " should cause keydown event");
+    if (aEvent.type != aExpectedData.type) {
+      return;
+    }
+    is(aEvent.defaultPrevented, expectedValue("defaultPrevented"),
+       desc + ".defaultPrevented is wrong");
+    is(aEvent.key, expectedValue("key"),
+       desc + ".key is wrong");
+    is(aEvent.code, expectedValue("code"),
+       desc + ".code is wrong");
+    is(aEvent.location, expectedValue("location"),
+       desc + ".location is wrong");
+    is(aEvent.repeat, expectedValue("repeat"),
+       desc + ".repeat is wrong");
+    is(aEvent.isComposing, expectedValue("isComposing"),
+       desc + ".isComposing is wrong");
+    is(aEvent.keyCode, expectedValue("keyCode"),
+       desc + ".keyCode is wrong");
+    is(aEvent.charCode, expectedValue("charCode"),
+       desc + ".charCode is wrong");
+    is(aEvent.shiftKey, expectedValue("shiftKey"),
+       desc + ".shiftKey is wrong");
+    is(aEvent.ctrlKey, expectedValue("ctrlKey"),
+       desc + ".ctrlKey is wrong");
+    is(aEvent.altKey, expectedValue("altKey"),
+       desc + ".altKey is wrong");
+    is(aEvent.metaKey, expectedValue("metaKey"),
+       desc + ".metaKey is wrong");
+    for (var i = 0; i < kModifiers.length; i++) {
+      is(aEvent.getModifierState(kModifiers[i]), aExpectedData[kModifiers[i]] !== undefined ? aExpectedData[kModifiers[i]] : false,
+         desc + ".getModifierState(\"" + kModifiers[i] + "\") is wrong");
+    }
+  }
+
+  window.addEventListener("keydown", handler);
+  window.addEventListener("keypress", handler);
+  window.addEventListener("keyup", handler);
+
+  input.value = "";
+  input.focus();
+
+
+  // Printable key test:
+  // Emulates pressing 'a' key.
+  var keyA = new KeyboardEvent("", { key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A });
+
+  reset();
+  var doDefaultKeydown = TIP.keydown(keyA);
+
+  is(doDefaultKeydown, TIP.KEYPRESS_IS_CONSUMED,
+     description + "TIP.keydown(keyA) should return 0x02 because the keypress event should be consumed by the input element");
+  is(events.length, 2,
+     description + "TIP.keydown(keyA) should cause keydown and keypress event");
+  checkKeyAttrs("TIP.keydown(keyA)", events[0],
+                { type: "keydown",  key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0 });
+  checkKeyAttrs("TIP.keydown(keyA)", events[1],
+                { type: "keypress", key: "a", code: "KeyA", keyCode: 0,                      charCode: "a".charCodeAt(0), defaultPrevented: true });
+  is(input.value, "a",
+     description + "input.value should be \"a\" which is inputted by TIP.keydown(keyA)");
+
+  // Emulates releasing 'a' key.
+  reset();
+  var doDefaultKeyup = TIP.keyup(keyA);
+  ok(doDefaultKeyup,
+     description + "TIP.keyup(keyA) should return true");
+  is(events.length, 1,
+     description + "TIP.keyup(keyA) should cause keyup event");
+  checkKeyAttrs("TIP.keyup(keyA)", events[0],
+                { type: "keyup",      key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0 });
+  is(input.value, "a",
+     description + "input.value should stay \"a\" which was inputted by TIP.keydown(keyA)");
+
+
+  // Non-printable key test:
+  // Emulates pressing Enter key.
+  var keyEnter = new KeyboardEvent("", { key: "Enter", code: "Enter" });
+
+  reset();
+  doDefaultKeydown = TIP.keydown(keyEnter);
+
+  is(doDefaultKeydown, 0,
+     description + "TIP.keydown(keyEnter) should return 0");
+  is(events.length, 2,
+     description + "TIP.keydown(keyEnter) should cause keydown and keypress event");
+  checkKeyAttrs("TIP.keydown(keyEnter)", events[0],
+                { type: "keydown",  key: "Enter", code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN });
+  checkKeyAttrs("TIP.keydown(keyEnter)", events[1],
+                { type: "keypress", key: "Enter", code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN });
+  is(input.value, "a",
+     description + "input.value should stay \"a\" which was inputted by TIP.keydown(keyA)");
+
+  // Emulates releasing Enter key.
+  reset();
+  doDefaultKeyup = TIP.keyup(keyEnter);
+  ok(doDefaultKeyup,
+     description + "TIP.keyup(keyEnter) should return true");
+  is(events.length, 1,
+     description + "TIP.keyup(keyEnter) should cause keyup event");
+  checkKeyAttrs("TIP.keyup(keyEnter)", events[0],
+                { type: "keyup",      key: "Enter", code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN });
+  is(input.value, "a",
+     description + "input.value should stay \"a\" which was inputted by TIP.keydown(keyA)");
+
+
+  // KEY_DEFAULT_PREVENTED should cause defaultPrevented = true and not cause keypress event
+  var keyB = new KeyboardEvent("", { key: "b", code: "KeyB", keyCode: KeyboardEvent.DOM_VK_B });
+
+  reset();
+  doDefaultKeydown = TIP.keydown(keyB, TIP.KEY_DEFAULT_PREVENTED);
+  doDefaultKeyup   = TIP.keyup(keyB, TIP.KEY_DEFAULT_PREVENTED);
+
+  is(doDefaultKeydown, TIP.KEYDOWN_IS_CONSUMED,
+     description + "TIP.keydown(keyB, TIP.KEY_DEFAULT_PREVENTED) should return 0x01 because it's marked as consumed at dispatching the event");
+  ok(!doDefaultKeyup,
+     description + "TIP.keyup(keyB, TIP.KEY_DEFAULT_PREVENTED) should return false because it's marked as consumed at dispatching the event");
+  is(events.length, 2,
+     description + "TIP.keydown(keyB, TIP.KEY_DEFAULT_PREVENTED) and TIP.keyup(keyB, TIP.KEY_DEFAULT_PREVENTED) should cause keydown and keyup event");
+  checkKeyAttrs("TIP.keydown(keyB, TIP.KEY_DEFAULT_PREVENTED) and TIP.keyup(keyB, TIP.KEY_DEFAULT_PREVENTED)", events[0],
+                { type: "keydown", key: "b", code: "KeyB", keyCode: KeyboardEvent.DOM_VK_B, defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyB, TIP.KEY_DEFAULT_PREVENTED) and TIP.keyup(keyB, TIP.KEY_DEFAULT_PREVENTED)", events[1],
+                { type: "keyup",   key: "b", code: "KeyB", keyCode: KeyboardEvent.DOM_VK_B, defaultPrevented: true });
+  is(input.value, "a",
+     description + "input.value shouldn't be modified by default prevented key events");
+
+  // Assume that KeyX causes inputting text "abc"
+  input.value = "";
+  var keyABC = new KeyboardEvent("", { key: "abc", code: "KeyX", keyCode: KeyboardEvent.DOM_VK_A });
+
+  reset();
+  doDefaultKeydown = TIP.keydown(keyABC);
+  doDefaultKeyup   = TIP.keyup(keyABC);
+
+  is(doDefaultKeydown, TIP.KEYPRESS_IS_CONSUMED,
+     description + "TIP.keydown(keyABC) should return false because the keypress events should be consumed by the input element");
+  ok(doDefaultKeyup,
+     description + "TIP.keyup(keyABC) should return true");
+  is(events.length, 5,
+     description + "TIP.keydown(keyABC) and TIP.keyup(keyABC) should cause keydown, keypress, keypress, keypress and keyup event");
+  checkKeyAttrs("TIP.keydown(keyABC) and TIP.keyup(keyABC)", events[0],
+                { type: "keydown",  key: "abc",           code: "KeyX", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0,                   defaultPrevented: false });
+  checkKeyAttrs("TIP.keydown(keyABC) and TIP.keyup(keyABC)", events[1],
+                { type: "keypress", key: "abc".charAt(0), code: "KeyX", keyCode: 0,                      charCode: "abc".charCodeAt(0), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyABC) and TIP.keyup(keyABC)", events[2],
+                { type: "keypress", key: "abc".charAt(1), code: "KeyX", keyCode: 0,                      charCode: "abc".charCodeAt(1), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyABC) and TIP.keyup(keyABC)", events[3],
+                { type: "keypress", key: "abc".charAt(2), code: "KeyX", keyCode: 0,                      charCode: "abc".charCodeAt(2), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyABC) and TIP.keyup(keyABC)", events[4],
+                { type: "keyup",    key: "abc",           code: "KeyX", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0,                   defaultPrevented: false });
+  is(input.value, "abc",
+     description + "input.value should be \"abc\"");
+
+  // Emulates pressing and releasing a key which introduces a surrogate pair.
+  async function test_press_and_release_surrogate_pair_key(
+    aTestPerSurrogateKeyPress,
+    aTestIllFormedUTF16KeyValue = false
+  ) {
+    await SpecialPowers.pushPrefEnv({
+      set: [
+        ["dom.event.keypress.dispatch_once_per_surrogate_pair", !aTestPerSurrogateKeyPress],
+        ["dom.event.keypress.key.allow_lone_surrogate", aTestIllFormedUTF16KeyValue],
+      ],
+    });
+
+    const settingDescription =
+      `aTestPerSurrogateKeyPress=${aTestPerSurrogateKeyPress}, aTestIllFormedUTF16KeyValue=${aTestIllFormedUTF16KeyValue}`;
+    const allowIllFormedUTF16 = aTestPerSurrogateKeyPress && aTestIllFormedUTF16KeyValue;
+    const keySurrogatePair = new KeyboardEvent("", { key: "\uD842\uDFB7", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A });
+
+    input.value = "";
+    reset();
+    doDefaultKeydown = TIP.keydown(keySurrogatePair);
+    doDefaultKeyup = TIP.keyup(keySurrogatePair);
+
+    is(
+      doDefaultKeydown,
+      TIP.KEYPRESS_IS_CONSUMED,
+      `${
+        description
+      }TIP.keydown(keySurrogatePair), ${
+        settingDescription
+      }, should return 0x02 because the keypress event should be consumed by the input element`
+    );
+    is(
+      doDefaultKeyup,
+      true,
+      `${description}TIP.keyup(keySurrogatePair) should return true`
+    );
+    is(
+      events.length,
+      aTestPerSurrogateKeyPress ? 4 : 3,
+      `${description}TIP.keydown(keySurrogatePair), ${
+        settingDescription
+      }, should cause keydown, keypress${
+        aTestPerSurrogateKeyPress ? ", keypress" : ""
+      } and keyup event`
+    );
+    checkKeyAttrs(
+      `${description}TIP.keydown(keySurrogatePair), ${settingDescription}`,
+      events[0],
+      {
+        type: "keydown",
+        key: "\uD842\uDFB7",
+        code: "KeyA",
+        keyCode: KeyboardEvent.DOM_VK_A,
+        charCode: 0,
+      }
+    );
+    if (aTestPerSurrogateKeyPress) {
+      checkKeyAttrs(
+        `${description}TIP.keydown(keySurrogatePair), ${settingDescription}`,
+        events[1],
+        {
+          type: "keypress",
+          key: allowIllFormedUTF16
+            ? "\uD842"
+            : "\uD842\uDFB7", // First keypress should have the surrogate pair
+          code: "KeyA",
+          keyCode: 0,
+          charCode: "\uD842\uDFB7".charCodeAt(0),
+          defaultPrevented: true,
+        }
+      );
+      checkKeyAttrs(
+        `${description}TIP.keydown(keySurrogatePair), ${settingDescription}`,
+        events[2],
+        {
+          type: "keypress",
+          key: allowIllFormedUTF16
+            ? "\uDFB7"
+            : "", // But the following keypress should have empty string, instead
+          code: "KeyA",
+          keyCode: 0,
+          charCode: "\uD842\uDFB7".charCodeAt(1),
+          defaultPrevented: true,
+        }
+      );
+    } else {
+      checkKeyAttrs(
+        `${description}TIP.keydown(keySurrogatePair), ${settingDescription}`,
+        events[1],
+        {
+          type: "keypress",
+          key: "\uD842\uDFB7",
+          code: "KeyA",
+          keyCode: 0,
+          charCode: 0x20BB7,
+          defaultPrevented: true,
+        }
+      );
+    }
+    checkKeyAttrs(
+      `${description}TIP.keyup(keySurrogatePair), ${settingDescription}`,
+      events[aTestPerSurrogateKeyPress ? 3 : 2],
+      {
+        type: "keyup",
+        key: "\uD842\uDFB7",
+        code: "KeyA",
+        keyCode: KeyboardEvent.DOM_VK_A,
+        charCode: 0,
+      }
+    );
+    is(
+      input.value,
+      "\uD842\uDFB7",
+      `${description}${settingDescription}, input.value should be the surrogate pair`
+    );
+  };
+
+  await test_press_and_release_surrogate_pair_key(true, true);
+  await test_press_and_release_surrogate_pair_key(true, false);
+  await test_press_and_release_surrogate_pair_key(false);
+
+  // If KEY_FORCE_PRINTABLE_KEY is specified, registered key names can be a printable key which inputs the specified value.
+  input.value = "";
+  var keyEnterPrintable = new KeyboardEvent("", { key: "Enter", code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN });
+
+  reset();
+  doDefaultKeydown = TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY);
+  doDefaultKeyup   = TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY);
+
+  is(doDefaultKeydown, TIP.KEYPRESS_IS_CONSUMED,
+     description + "TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) should return 0x02 because the keypress events should be consumed by the input element");
+  ok(doDefaultKeyup,
+     description + "TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) should return true");
+  is(events.length, 7,
+     description + "TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) and TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) should cause keydown, keypress, keypress, keypress, keypress, keypress and keyup event");
+  checkKeyAttrs("TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) and TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY)", events[0],
+                { type: "keydown",  key: "Enter",           code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN, charCode: 0,                    defaultPrevented: false });
+  checkKeyAttrs("TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) and TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY)", events[1],
+                { type: "keypress", key: "Enter".charAt(0), code: "Enter", keyCode: 0,                           charCode: "Enter".charCodeAt(0), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) and TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY)", events[2],
+                { type: "keypress", key: "Enter".charAt(1), code: "Enter", keyCode: 0,                           charCode: "Enter".charCodeAt(1), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) and TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY)", events[3],
+                { type: "keypress", key: "Enter".charAt(2), code: "Enter", keyCode: 0,                           charCode: "Enter".charCodeAt(2), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) and TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY)", events[4],
+                { type: "keypress", key: "Enter".charAt(3), code: "Enter", keyCode: 0,                           charCode: "Enter".charCodeAt(3), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) and TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY)", events[5],
+                { type: "keypress", key: "Enter".charAt(4), code: "Enter", keyCode: 0,                           charCode: "Enter".charCodeAt(4), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY) and TIP.keyup(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY)", events[6],
+                { type: "keyup",    key: "Enter",           code: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN, charCode: 0,                     defaultPrevented: false });
+  is(input.value, "Enter",
+     description + "input.value should be \"Enter\"");
+
+  // modifiers should be ignored.
+  var keyWithModifiers = new KeyboardEvent("", { key: "Escape", code: "Escape", shiftKey: true, ctrlKey: true, altKey: true, metaKey: true });
+
+  reset();
+  doDefaultKeydown = TIP.keydown(keyWithModifiers);
+  doDefaultKeyup   = TIP.keyup(keyWithModifiers);
+
+  is(doDefaultKeydown, 0,
+     description + "TIP.keydown(keyWithModifiers) should return 0");
+  ok(doDefaultKeyup,
+     description + "TIP.keyup(keyWithModifiers) should return true");
+  is(events.length, 3,
+     description + "TIP.keydown(keyWithModifiers) and TIP.keyup(keyWithModifiers) should cause keydown, keypress and keyup event");
+  checkKeyAttrs("TIP.keydown(keyWithModifiers) and TIP.keyup(keyWithModifiers)", events[0],
+                { type: "keydown",  key: "Escape", code: "Escape", keyCode: KeyboardEvent.DOM_VK_ESCAPE });
+  checkKeyAttrs("TIP.keydown(keyWithModifiers) and TIP.keyup(keyWithModifiers)", events[1],
+                { type: "keypress", key: "Escape", code: "Escape", keyCode: KeyboardEvent.DOM_VK_ESCAPE });
+  checkKeyAttrs("TIP.keydown(keyWithModifiers) and TIP.keyup(keyWithModifiers)", events[2],
+                { type: "keyup",    key: "Escape", code: "Escape", keyCode: KeyboardEvent.DOM_VK_ESCAPE });
+  is(input.value, "Enter",
+     description + "input.value should stay \"Enter\" which was inputted by TIP.keydown(keyEnterPrintable, TIP.KEY_FORCE_PRINTABLE_KEY)");
+
+  // Call preventDefault() at keydown
+  input.value = "";
+  reset();
+  doPreventDefaults = [ "keydown" ];
+  doDefaultKeydown = TIP.keydown(keyA);
+  doDefaultKeyup   = TIP.keyup(keyA);
+
+  is(doDefaultKeydown, TIP.KEYDOWN_IS_CONSUMED,
+     description + "TIP.keydown(keyA) should return 0x01 because keydown event's preventDefault should be called");
+  ok(doDefaultKeyup,
+     description + "TIP.keyup(keyA) should return true");
+  is(events.length, 2,
+     description + "TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keydown should cause keydown and keyup event");
+  checkKeyAttrs("TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keydown", events[0],
+                { type: "keydown",  key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keydown", events[1],
+                { type: "keyup",    key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, defaultPrevented: false });
+  is(input.value, "",
+     description + "input.value shouldn't be modified by TIP.keyup(keyA) if the keydown event is consumed");
+
+  // Call preventDefault() at keypress
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  doDefaultKeydown = TIP.keydown(keyA);
+  doDefaultKeyup   = TIP.keyup(keyA);
+
+  is(doDefaultKeydown, TIP.KEYPRESS_IS_CONSUMED,
+     description + "TIP.keydown(keyA) should return 0x02 because keypress event's preventDefault should be called");
+  ok(doDefaultKeyup,
+     description + "TIP.keyup(keyA) should return true");
+  is(events.length, 3,
+     description + "TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keypress should cause keydown, keypress and keyup event");
+  checkKeyAttrs("TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keypress", events[0],
+                { type: "keydown",  key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0,                 defaultPrevented: false });
+  checkKeyAttrs("TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keypress", events[1],
+                { type: "keypress", key: "a", code: "KeyA", keyCode: 0,                      charCode: "a".charCodeAt(0), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keypress", events[2],
+                { type: "keyup",    key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0,                 defaultPrevented: false });
+  is(input.value, "",
+     description + "input.value shouldn't be modified by TIP.keyup(keyA) if the keypress event is consumed");
+
+  // Call preventDefault() at keyup
+  input.value = "";
+  reset();
+  doPreventDefaults = [ "keyup" ];
+  doDefaultKeydown = TIP.keydown(keyA);
+  doDefaultKeyup   = TIP.keyup(keyA);
+
+  is(doDefaultKeydown, TIP.KEYPRESS_IS_CONSUMED,
+     description + "TIP.keydown(keyA) should return 0x02 because the key event should be consumed by the input element");
+  ok(!doDefaultKeyup,
+     description + "TIP.keyup(keyA) should return false because keyup event's preventDefault should be called");
+  is(events.length, 3,
+     description + "TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keyup should cause keydown, keypress and keyup event");
+  checkKeyAttrs("TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keyup", events[0],
+                { type: "keydown",  key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0,                 defaultPrevented: false });
+  checkKeyAttrs("TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keyup", events[1],
+                { type: "keypress", key: "a", code: "KeyA", keyCode: 0,                      charCode: "a".charCodeAt(0), defaultPrevented: true });
+  checkKeyAttrs("TIP.keydown(keyA) and TIP.keyup(keyA) with preventing default of keyup", events[2],
+                { type: "keyup",    key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0,                 defaultPrevented: true });
+  is(input.value, "a",
+     description + "input.value should be \"a\" by TIP.keyup(keyA) even if the keyup event is consumed");
+
+  // key events during composition
+  try {
+    Services.prefs.setBoolPref("dom.keyboardevent.dispatch_during_composition", false);
+
+    ok(TIP.startComposition(), "TIP.startComposition() should start composition");
+
+    input.value = "";
+    reset();
+    TIP.keydown(keyA);
+    is(events.length, 0,
+       description + "TIP.keydown(keyA) shouldn't cause key events during composition if it's disabled by the pref");
+    reset();
+    TIP.keyup(keyA);
+    is(events.length, 0,
+       description + "TIP.keyup(keyA) shouldn't cause key events during composition if it's disabled by the pref");
+
+    Services.prefs.setBoolPref("dom.keyboardevent.dispatch_during_composition", true);
+    reset();
+    TIP.keydown(keyA);
+    is(events.length, 1,
+       description + "TIP.keydown(keyA) should cause keydown event even composition if it's enabled by the pref");
+    checkKeyAttrs("TIP.keydown(keyA) during composition", events[0],
+                  { type: "keydown",  key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0, isComposing: true });
+    reset();
+    TIP.keyup(keyA);
+    is(events.length, 1,
+       description + "TIP.keyup(keyA) should cause keyup event even composition if it's enabled by the pref");
+    checkKeyAttrs("TIP.keyup(keyA) during composition", events[0],
+                  { type: "keyup",    key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A, charCode: 0, isComposing: true });
+
+  } finally {
+    TIP.cancelComposition();
+    Services.prefs.clearUserPref("dom.keyboardevent.dispatch_during_composition");
+  }
+
+  // Test .location computation
+  const kCodeToLocation = [
+    { code: "BracketLeft",              location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "BracketRight",             location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Comma",                    location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit0",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit1",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit2",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit3",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit4",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit5",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit6",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit7",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit8",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Digit9",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Equal",                    location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Minus",                    location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Period",                   location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Slash",                    location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "AltLeft",                  location: KeyboardEvent.DOM_KEY_LOCATION_LEFT },
+    { code: "AltRight",                 location: KeyboardEvent.DOM_KEY_LOCATION_RIGHT },
+    { code: "CapsLock",                 location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "ContextMenu",              location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "ControlLeft",              location: KeyboardEvent.DOM_KEY_LOCATION_LEFT },
+    { code: "ControlRight",             location: KeyboardEvent.DOM_KEY_LOCATION_RIGHT },
+    { code: "Enter",                    location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "MetaLeft",                 location: KeyboardEvent.DOM_KEY_LOCATION_LEFT },
+    { code: "MetaRight",                location: KeyboardEvent.DOM_KEY_LOCATION_RIGHT },
+    { code: "ShiftLeft",                location: KeyboardEvent.DOM_KEY_LOCATION_LEFT },
+    { code: "ShiftRight",               location: KeyboardEvent.DOM_KEY_LOCATION_RIGHT },
+    { code: "Space",                    location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Tab",                      location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "ArrowDown",                location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "ArrowLeft",                location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "ArrowRight",               location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "ArrowUp",                  location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "NumLock",                  location: KeyboardEvent.DOM_KEY_LOCATION_STANDARD },
+    { code: "Numpad0",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "Numpad1",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "Numpad2",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "Numpad3",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "Numpad4",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "Numpad5",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "Numpad6",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "Numpad7",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "Numpad8",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "Numpad9",                  location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadAdd",                location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadBackspace",          location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadClear",              location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadClearEntry",         location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadComma",              location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadDecimal",            location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadDivide",             location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadEnter",              location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadEqual",              location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadMemoryAdd",          location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadMemoryClear",        location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadMemoryRecall",       location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadMemoryStore",        location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadMemorySubtract",     location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadMultiply",           location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadParenLeft",          location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadParenRight",         location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+    { code: "NumpadSubtract",           location: KeyboardEvent.DOM_KEY_LOCATION_NUMPAD },
+  ];
+  for (let i = 0; i < kCodeToLocation.length; i++) {
+    let keyEvent = new KeyboardEvent("", { code: kCodeToLocation[i].code });
+    reset();
+    doPreventDefaults = [ "keypress" ];
+    // If the location isn't initialized or initialized with 0, it should be computed from the code value.
+    TIP.keydown(keyEvent);
+    TIP.keyup(keyEvent);
+    let longDesc = description + "testing computation of .location of \"" + kCodeToLocation[i].code + "\", ";
+    is(events.length, 3,
+       longDesc + "keydown, keypress and keyup events should be fired");
+    for (let j = 0; j < events.length; j++) {
+      is(events[j].location, kCodeToLocation[i].location,
+         longDesc + " type=\"" + events[j].type + "\", location value is wrong");
+    }
+    // However, if KEY_KEEP_KEY_LOCATION_STANDARD is specified, .location value should be kept as DOM_KEY_LOCATION_STANDARD (0).
+    reset();
+    doPreventDefaults = [ "keypress" ];
+    TIP.keydown(keyEvent, TIP.KEY_KEEP_KEY_LOCATION_STANDARD);
+    TIP.keyup(keyEvent, TIP.KEY_KEEP_KEY_LOCATION_STANDARD);
+    longDesc = description + "testing if .location is forcibly set to DOM_KEY_LOCATION_STANDARD, ";
+    is(events.length, 3,
+       longDesc + "keydown, keypress and keyup events should be fired");
+    for (let j = 0; j < events.length; j++) {
+      is(events[j].location, KeyboardEvent.DOM_KEY_LOCATION_STANDARD,
+         longDesc + " type=\"" + events[j].type + "\", location value is not 0");
+    }
+    // If .location is initialized with non-zero value, the value shouldn't be computed again.
+    let keyEventWithLocation = new KeyboardEvent("", { code: kCodeToLocation[i].code, location: 0xFF });
+    reset();
+    doPreventDefaults = [ "keypress" ];
+    TIP.keydown(keyEventWithLocation);
+    TIP.keyup(keyEventWithLocation);
+    longDesc = description + "testing if .location is not computed for \"" + kCodeToLocation[i].location + "\", ";
+    is(events.length, 3,
+       longDesc + "keydown, keypress and keyup events should be fired");
+    for (let j = 0; j < events.length; j++) {
+      is(events[j].location, 0xFF,
+         longDesc + " type=\"" + events[j].type + "\", location shouldn't be computed if it's initialized with non-zero value");
+    }
+  }
+
+  // Test .keyCode value computation
+  const kKeyToKeyCode = [
+    { key: "Cancel",                    keyCode: KeyboardEvent.DOM_VK_CANCEL },
+    { key: "Help",                      keyCode: KeyboardEvent.DOM_VK_HELP },
+    { key: "Backspace",                 keyCode: KeyboardEvent.DOM_VK_BACK_SPACE },
+    { key: "Tab",                       keyCode: KeyboardEvent.DOM_VK_TAB },
+    { key: "Clear",                     keyCode: KeyboardEvent.DOM_VK_CLEAR },
+    { key: "Enter",                     keyCode: KeyboardEvent.DOM_VK_RETURN },
+    { key: "Shift",                     keyCode: KeyboardEvent.DOM_VK_SHIFT,              isModifier: true },
+    { key: "Control",                   keyCode: KeyboardEvent.DOM_VK_CONTROL,            isModifier: true },
+    { key: "Alt",                       keyCode: KeyboardEvent.DOM_VK_ALT,                isModifier: true },
+    { key: "Pause",                     keyCode: KeyboardEvent.DOM_VK_PAUSE },
+    { key: "CapsLock",                  keyCode: KeyboardEvent.DOM_VK_CAPS_LOCK,          isModifier: true, isLockableModifier: true },
+    { key: "Hiragana",                  keyCode: KeyboardEvent.DOM_VK_KANA },
+    { key: "Katakana",                  keyCode: KeyboardEvent.DOM_VK_KANA },
+    { key: "HiraganaKatakana",          keyCode: KeyboardEvent.DOM_VK_KANA },
+    { key: "KanaMode",                  keyCode: KeyboardEvent.DOM_VK_KANA },
+    { key: "HangulMode",                keyCode: KeyboardEvent.DOM_VK_HANGUL },
+    { key: "Eisu",                      keyCode: KeyboardEvent.DOM_VK_EISU },
+    { key: "JunjaMode",                 keyCode: KeyboardEvent.DOM_VK_JUNJA },
+    { key: "FinalMode",                 keyCode: KeyboardEvent.DOM_VK_FINAL },
+    { key: "HanjaMode",                 keyCode: KeyboardEvent.DOM_VK_HANJA },
+    { key: "KanjiMode",                 keyCode: KeyboardEvent.DOM_VK_KANJI },
+    { key: "Escape",                    keyCode: KeyboardEvent.DOM_VK_ESCAPE },
+    { key: "Convert",                   keyCode: KeyboardEvent.DOM_VK_CONVERT },
+    { key: "NonConvert",                keyCode: KeyboardEvent.DOM_VK_NONCONVERT },
+    { key: "Accept",                    keyCode: KeyboardEvent.DOM_VK_ACCEPT },
+    { key: "ModeChange",                keyCode: KeyboardEvent.DOM_VK_MODECHANGE },
+    { key: "PageUp",                    keyCode: KeyboardEvent.DOM_VK_PAGE_UP },
+    { key: "PageDown",                  keyCode: KeyboardEvent.DOM_VK_PAGE_DOWN },
+    { key: "End",                       keyCode: KeyboardEvent.DOM_VK_END },
+    { key: "Home",                      keyCode: KeyboardEvent.DOM_VK_HOME },
+    { key: "ArrowLeft",                 keyCode: KeyboardEvent.DOM_VK_LEFT },
+    { key: "ArrowUp",                   keyCode: KeyboardEvent.DOM_VK_UP },
+    { key: "ArrowRight",                keyCode: KeyboardEvent.DOM_VK_RIGHT },
+    { key: "ArrowDown",                 keyCode: KeyboardEvent.DOM_VK_DOWN },
+    { key: "Select",                    keyCode: KeyboardEvent.DOM_VK_SELECT },
+    { key: "Print",                     keyCode: KeyboardEvent.DOM_VK_PRINT },
+    { key: "Execute",                   keyCode: KeyboardEvent.DOM_VK_EXECUTE },
+    { key: "PrintScreen",               keyCode: KeyboardEvent.DOM_VK_PRINTSCREEN },
+    { key: "Insert",                    keyCode: KeyboardEvent.DOM_VK_INSERT },
+    { key: "Delete",                    keyCode: KeyboardEvent.DOM_VK_DELETE },
+    { key: "ContextMenu",               keyCode: KeyboardEvent.DOM_VK_CONTEXT_MENU },
+    { key: "F1",                        keyCode: KeyboardEvent.DOM_VK_F1 },
+    { key: "F2",                        keyCode: KeyboardEvent.DOM_VK_F2 },
+    { key: "F3",                        keyCode: KeyboardEvent.DOM_VK_F3 },
+    { key: "F4",                        keyCode: KeyboardEvent.DOM_VK_F4 },
+    { key: "F5",                        keyCode: KeyboardEvent.DOM_VK_F5 },
+    { key: "F6",                        keyCode: KeyboardEvent.DOM_VK_F6 },
+    { key: "F7",                        keyCode: KeyboardEvent.DOM_VK_F7 },
+    { key: "F8",                        keyCode: KeyboardEvent.DOM_VK_F8 },
+    { key: "F9",                        keyCode: KeyboardEvent.DOM_VK_F9 },
+    { key: "F10",                       keyCode: KeyboardEvent.DOM_VK_F10 },
+    { key: "F11",                       keyCode: KeyboardEvent.DOM_VK_F11 },
+    { key: "F12",                       keyCode: KeyboardEvent.DOM_VK_F12 },
+    { key: "F13",                       keyCode: KeyboardEvent.DOM_VK_F13 },
+    { key: "F14",                       keyCode: KeyboardEvent.DOM_VK_F14 },
+    { key: "F15",                       keyCode: KeyboardEvent.DOM_VK_F15 },
+    { key: "F16",                       keyCode: KeyboardEvent.DOM_VK_F16 },
+    { key: "F17",                       keyCode: KeyboardEvent.DOM_VK_F17 },
+    { key: "F18",                       keyCode: KeyboardEvent.DOM_VK_F18 },
+    { key: "F19",                       keyCode: KeyboardEvent.DOM_VK_F19 },
+    { key: "F20",                       keyCode: KeyboardEvent.DOM_VK_F20 },
+    { key: "F21",                       keyCode: KeyboardEvent.DOM_VK_F21 },
+    { key: "F22",                       keyCode: KeyboardEvent.DOM_VK_F22 },
+    { key: "F23",                       keyCode: KeyboardEvent.DOM_VK_F23 },
+    { key: "F24",                       keyCode: KeyboardEvent.DOM_VK_F24 },
+    { key: "NumLock",                   keyCode: KeyboardEvent.DOM_VK_NUM_LOCK,           isModifier: true, isLockableModifier: true },
+    { key: "ScrollLock",                keyCode: KeyboardEvent.DOM_VK_SCROLL_LOCK,        isModifier: true, isLockableModifier: true },
+    { key: "AudioVolumeMute",           keyCode: KeyboardEvent.DOM_VK_VOLUME_MUTE },
+    { key: "AudioVolumeDown",           keyCode: KeyboardEvent.DOM_VK_VOLUME_DOWN },
+    { key: "AudioVolumeUp",             keyCode: KeyboardEvent.DOM_VK_VOLUME_UP },
+    { key: "Meta",                      keyCode: kIsMac
+                                          ? KeyboardEvent.DOM_VK_META
+                                          : KeyboardEvent.DOM_VK_WIN,                     isModifier: true },
+    { key: "AltGraph",                  keyCode: KeyboardEvent.DOM_VK_ALTGR,              isModifier: true },
+    { key: "Attn",                      keyCode: KeyboardEvent.DOM_VK_ATTN },
+    { key: "CrSel",                     keyCode: KeyboardEvent.DOM_VK_CRSEL },
+    { key: "ExSel",                     keyCode: KeyboardEvent.DOM_VK_EXSEL },
+    { key: "EraseEof",                  keyCode: KeyboardEvent.DOM_VK_EREOF },
+    { key: "Play",                      keyCode: KeyboardEvent.DOM_VK_PLAY },
+    { key: "ZoomToggle",                keyCode: KeyboardEvent.DOM_VK_ZOOM },
+    { key: "ZoomIn",                    keyCode: KeyboardEvent.DOM_VK_ZOOM },
+    { key: "ZoomOut",                   keyCode: KeyboardEvent.DOM_VK_ZOOM },
+    { key: "Unidentified",              keyCode: 0 },
+    { key: "a",                         keyCode: 0, isPrintable: true },
+    { key: "A",                         keyCode: 0, isPrintable: true },
+    { key: " ",                         keyCode: 0, isPrintable: true },
+    { key: "",                          keyCode: 0, isPrintable: true },
+  ];
+
+  for (let i = 0; i < kKeyToKeyCode.length; i++) {
+    let keyEvent = new KeyboardEvent("", { key: kKeyToKeyCode[i].key });
+    var causeKeypress = !kKeyToKeyCode[i].isModifier;
+    var baseFlags = kKeyToKeyCode[i].isPrintable ? 0 : TIP.KEY_NON_PRINTABLE_KEY;
+    reset();
+    doPreventDefaults = [ "keypress" ];
+    // If the keyCode isn't initialized or initialized with 0, it should be computed from the key value only when it's a printable key.
+    TIP.keydown(keyEvent, baseFlags);
+    TIP.keyup(keyEvent, baseFlags);
+    let longDesc = description + "testing computation of .keyCode of \"" + kKeyToKeyCode[i].key + "\", ";
+    is(events.length, causeKeypress ? 3 : 2,
+       longDesc + "keydown" + (causeKeypress ? ", keypress" : "") + " and keyup events should be fired");
+    for (let j = 0; j < events.length; j++) {
+      is(events[j].keyCode, events[j].type == "keypress" && kKeyToKeyCode[i].isPrintable ? 0 : kKeyToKeyCode[i].keyCode,
+         longDesc + " type=\"" + events[j].type + "\", keyCode value is wrong");
+    }
+    // However, if KEY_KEEP_KEYCODE_ZERO is specified, .keyCode value should be kept as 0.
+    reset();
+    doPreventDefaults = [ "keypress" ];
+    TIP.keydown(keyEvent, TIP.KEY_KEEP_KEYCODE_ZERO | baseFlags);
+    TIP.keyup(keyEvent, TIP.KEY_KEEP_KEYCODE_ZERO | baseFlags);
+    longDesc = description + "testing if .keyCode is forcibly set to KEY_KEEP_KEYCODE_ZERO, ";
+    is(events.length, causeKeypress ? 3 : 2,
+       longDesc + "keydown" + (causeKeypress ? ", keypress" : "") + " and keyup events should be fired");
+    for (let j = 0; j < events.length; j++) {
+      is(events[j].keyCode, 0,
+         longDesc + " type=\"" + events[j].type + "\", keyCode value is not 0");
+    }
+    // If .keyCode is initialized with non-zero value, the value shouldn't be computed again.
+    let keyEventWithLocation = new KeyboardEvent("", { key: kKeyToKeyCode[i].key, keyCode: 0xFF });
+    reset();
+    doPreventDefaults = [ "keypress" ];
+    TIP.keydown(keyEventWithLocation, baseFlags);
+    TIP.keyup(keyEventWithLocation, baseFlags);
+    longDesc = description + "testing if .keyCode is not computed for \"" + kKeyToKeyCode[i].key + "\", ";
+    is(events.length, causeKeypress ? 3 : 2,
+       longDesc + "keydown" + (causeKeypress ? ", keypress" : "") + " and keyup events should be fired");
+    for (let j = 0; j < events.length; j++) {
+      is(events[j].keyCode, events[j].type == "keypress" && kKeyToKeyCode[i].isPrintable ? 0 : 0xFF,
+         longDesc + " type=\"" + events[j].type + "\", keyCode shouldn't be computed if it's initialized with non-zero value");
+    }
+    // Unlock lockable modifier if the key is a lockable modifier key.
+    if (kKeyToKeyCode[i].isLockableModifier) {
+      TIP.keydown(keyEvent, baseFlags);
+      TIP.keyup(keyEvent, baseFlags);
+    }
+  }
+
+  // Modifier state tests
+  var sharedTIP = createTIP();
+  ok(sharedTIP.beginInputTransactionForTests(otherWindow),
+     description + "sharedTIP.beginInputTransactionForTests(otherWindow) should return true");
+  TIP.shareModifierStateOf(sharedTIP);
+  var independentTIP = createTIP();
+  const kModifierKeys = [
+    { key: "Alt",        code: "AltLeft",      isLockable: false },
+    { key: "Alt",        code: "AltRight",     isLockable: false },
+    { key: "AltGraph",   code: "AltRight",     isLockable: false },
+    { key: "CapsLock",   code: "CapsLock",     isLockable: true },
+    { key: "Control",    code: "ControlLeft",  isLockable: false },
+    { key: "Control",    code: "ControlRight", isLockable: false },
+    { key: "Fn",         code: "Fn",           isLockable: false },
+    { key: "FnLock",     code: "",             isLockable: true },
+    { key: "Meta",       code: "MetaLeft",     isLockable: false },
+    { key: "Meta",       code: "MetaRight",    isLockable: false },
+    { key: "NumLock",    code: "NumLock",      isLockable: true },
+    { key: "ScrollLock", code: "ScrollLock",   isLockable: true },
+    { key: "Shift",      code: "ShiftLeft",    isLockable: false },
+    { key: "Shift",      code: "ShiftRight",   isLockable: false },
+    { key: "Symbol",     code: "",             isLockable: false },
+    { key: "SymbolLock", code: "",             isLockable: true },
+  ];
+
+  function checkModifiers(aTestDesc, aEvent, aType, aKey, aCode, aModifiers)
+  {
+    var desc = description + aTestDesc + ", type=\"" + aEvent.type + "\", key=\"" + aEvent.key + "\", code=\"" + aEvent.code + "\"";
+    is(aEvent.type, aType,
+       desc + ", .type value is wrong");
+    if (aEvent.type != aType) {
+      return;
+    }
+    is(aEvent.key, aKey,
+       desc + ", .key value is wrong");
+    is(aEvent.code, aCode,
+       desc + ", .code value is wrong");
+    is(aEvent.altKey, aModifiers.includes("Alt"),
+       desc + ", .altKey value is wrong");
+    is(aEvent.ctrlKey, aModifiers.includes("Control"),
+       desc + ", .ctrlKey value is wrong");
+    is(aEvent.metaKey, aModifiers.includes("Meta"),
+       desc + ", .metaKey value is wrong");
+    is(aEvent.shiftKey, aModifiers.includes("Shift"),
+       desc + ", .shiftKey value is wrong");
+    /* eslint-disable-next-line no-shadow */
+    for (var i = 0; i < kModifiers.length; i++) {
+      is(aEvent.getModifierState(kModifiers[i]), aModifiers.includes(kModifiers[i]),
+         desc + ", .getModifierState(\"" + kModifiers[i] + "\") returns wrong value");
+    }
+  }
+
+  function checkAllTIPModifiers(aTestDesc, aModifiers)
+  {
+    /* eslint-disable-next-line no-shadow */
+    for (var i = 0; i < kModifiers.length; i++) {
+      is(TIP.getModifierState(kModifiers[i]), aModifiers.includes(kModifiers[i]),
+         aTestDesc + ", TIP.getModifierState(\"" + kModifiers[i] + "\") returns wrong value");
+      is(sharedTIP.getModifierState(kModifiers[i]), TIP.getModifierState(kModifiers[i]),
+         aTestDesc + ", sharedTIP.getModifierState(\"" + kModifiers[i] + "\") returns different value from TIP");
+      is(independentTIP.getModifierState(kModifiers[i]), false,
+         aTestDesc + ", independentTIP.getModifierState(\"" + kModifiers[i] + "\") should return false");
+    }
+  }
+
+  // First, all modifiers must be false.
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  TIP.keydown(keyA);
+  TIP.keyup(keyA);
+
+  is(events.length, 3,
+     description + "TIP.keydown(keyA) and TIP.keyup(keyA) should cause keydown, keypress and keyup");
+  checkModifiers("Before dispatching modifier key events", events[0], "keydown",  "a", "KeyA", []);
+  checkModifiers("Before dispatching modifier key events", events[1], "keypress", "a", "KeyA", []);
+  checkModifiers("Before dispatching modifier key events", events[2], "keyup",    "a", "KeyA", []);
+
+  // Test each modifier keydown/keyup causes activating/inactivating the modifier state.
+  for (var i = 0; i < kModifierKeys.length; i++) {
+    reset();
+    doPreventDefaults = [ "keypress" ];
+    var modKey = new KeyboardEvent("", { key: kModifierKeys[i].key, code: kModifierKeys[i].code });
+    let testDesc = "A modifier key \"" + kModifierKeys[i].key + "\" (\"" + kModifierKeys[i].code + "\") and a printable key";
+    if (!kModifierKeys[i].isLockable) {
+      TIP.keydown(modKey);
+      checkAllTIPModifiers(testDesc + ", \"" + kModifierKeys[i].key + "\" keydown", [ kModifierKeys[i].key ]);
+      TIP.keydown(keyA);
+      checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ kModifierKeys[i].key ]);
+      TIP.keyup(keyA);
+      checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ kModifierKeys[i].key ]);
+      TIP.keyup(modKey);
+      checkAllTIPModifiers(testDesc + ", \"" + kModifierKeys[i].key + "\" keyup", [ ]);
+      is(events.length, 5,
+         description + testDesc + " should cause 5 events");
+      checkModifiers(testDesc, events[0], "keydown",  kModifierKeys[i].key, kModifierKeys[i].code, [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[1], "keydown",  "a",                  "KeyA",                [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[2], "keypress", "a",                  "KeyA",                [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[3], "keyup",    "a",                  "KeyA",                [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[4], "keyup",    kModifierKeys[i].key, kModifierKeys[i].code, [ ]);
+
+      // KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT shouldn't cause key events of modifier keys, but should modify the modifier state.
+      reset();
+      doPreventDefaults = [ "keypress" ];
+      testDesc = "A modifier key \"" + kModifierKeys[i].key + "\" (\"" + kModifierKeys[i].code + "\") with KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT and a printable key";
+      TIP.keydown(modKey, TIP.KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT);
+      TIP.keydown(keyA);
+      TIP.keyup(keyA);
+      TIP.keyup(modKey, TIP.KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT);
+      TIP.keydown(keyA);
+      TIP.keyup(keyA);
+      is(events.length, 6,
+         description + testDesc + " should cause 6 events");
+      checkModifiers(testDesc, events[0], "keydown",  "a", "KeyA", [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[1], "keypress", "a", "KeyA", [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[2], "keyup",    "a", "KeyA", [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[3], "keydown",  "a", "KeyA", [ ]);
+      checkModifiers(testDesc, events[4], "keypress", "a", "KeyA", [ ]);
+      checkModifiers(testDesc, events[5], "keyup",    "a", "KeyA", [ ]);
+    } else {
+      TIP.keydown(modKey);
+      checkAllTIPModifiers(testDesc + ", \"" + kModifierKeys[i].key + "\" first keydown", [ kModifierKeys[i].key ]);
+      TIP.keyup(modKey);
+      checkAllTIPModifiers(testDesc + ", \"" + kModifierKeys[i].key + "\" first keyup", [ kModifierKeys[i].key ]);
+      TIP.keydown(keyA);
+      checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ kModifierKeys[i].key ]);
+      TIP.keyup(keyA);
+      checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ kModifierKeys[i].key ]);
+      TIP.keydown(modKey);
+      checkAllTIPModifiers(testDesc + ", \"" + kModifierKeys[i].key + "\" second keydown", [ ]);
+      TIP.keyup(modKey);
+      checkAllTIPModifiers(testDesc + ", \"" + kModifierKeys[i].key + "\" second keyup", [ ]);
+      is(events.length, 7,
+         description + testDesc + " should cause 7 events");
+      checkModifiers(testDesc, events[0], "keydown",  kModifierKeys[i].key, kModifierKeys[i].code, [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[1], "keyup",    kModifierKeys[i].key, kModifierKeys[i].code, [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[2], "keydown",  "a",                  "KeyA",                [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[3], "keypress", "a",                  "KeyA",                [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[4], "keyup",    "a",                  "KeyA",                [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[5], "keydown",  kModifierKeys[i].key, kModifierKeys[i].code, [ ]);
+      checkModifiers(testDesc, events[6], "keyup",    kModifierKeys[i].key, kModifierKeys[i].code, [ ]);
+
+      // KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT shouldn't cause key events of modifier keys, but should modify the modifier state.
+      reset();
+      doPreventDefaults = [ "keypress" ];
+      testDesc = "A modifier key \"" + kModifierKeys[i].key + "\" (\"" + kModifierKeys[i].code + "\") with KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT and a printable key";
+      TIP.keydown(modKey, TIP.KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT);
+      TIP.keyup(modKey, TIP.KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT);
+      TIP.keydown(keyA);
+      TIP.keyup(keyA);
+      TIP.keydown(modKey, TIP.KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT);
+      TIP.keyup(modKey, TIP.KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT);
+      TIP.keydown(keyA);
+      TIP.keyup(keyA);
+      is(events.length, 6,
+         description + testDesc + " should cause 6 events");
+      checkModifiers(testDesc, events[0], "keydown",  "a",                  "KeyA",                [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[1], "keypress", "a",                  "KeyA",                [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[2], "keyup",    "a",                  "KeyA",                [ kModifierKeys[i].key ]);
+      checkModifiers(testDesc, events[3], "keydown",  "a",                  "KeyA",                [ ]);
+      checkModifiers(testDesc, events[4], "keypress", "a",                  "KeyA",                [ ]);
+      checkModifiers(testDesc, events[5], "keyup",    "a",                  "KeyA",                [ ]);
+    }
+  }
+
+  // Modifier state should be inactivated only when all pressed modifiers are released
+  var shiftLeft = new KeyboardEvent("", { key: "Shift", code: "ShiftLeft" });
+  var shiftRight = new KeyboardEvent("", { key: "Shift", code: "ShiftRight" });
+  var shiftVirtual = new KeyboardEvent("", { key: "Shift", code: "" });
+  var altGrVirtual = new KeyboardEvent("", { key: "AltGraph", code: "" });
+  var ctrlVirtual = new KeyboardEvent("", { key: "Control", code: "" });
+
+  let testDesc = "ShiftLeft press -> ShiftRight press -> ShiftRight release -> ShiftLeft release";
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  TIP.keydown(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keydown", [ "Shift" ]);
+  TIP.keydown(shiftRight);
+  checkAllTIPModifiers(testDesc + ", Right-Shift keydown", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ "Shift" ]);
+  TIP.keyup(shiftRight);
+  checkAllTIPModifiers(testDesc + ", Right-Shift keyup", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Right-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Right-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keyup", [ ]);
+
+  is(events.length, 10,
+     description + testDesc + " should cause 10 events");
+  checkModifiers(testDesc, events[0], "keydown",  "Shift", "ShiftLeft",  [ "Shift" ]);
+  checkModifiers(testDesc, events[1], "keydown",  "Shift", "ShiftRight", [ "Shift" ]);
+  checkModifiers(testDesc, events[2], "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[3], "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[4], "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[5], "keyup",    "Shift", "ShiftRight", [ "Shift" ]);
+  checkModifiers(testDesc, events[6], "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[7], "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[8], "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[9], "keyup",    "Shift", "ShiftLeft",  [ ]);
+
+  testDesc = "ShiftLeft press -> ShiftRight press -> ShiftLeft release -> ShiftRight release";
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  TIP.keydown(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keydown", [ "Shift" ]);
+  TIP.keydown(shiftRight);
+  checkAllTIPModifiers(testDesc + ", Right-Shift keydown", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ "Shift" ]);
+  TIP.keyup(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keyup", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Left-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Left-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(shiftRight);
+  checkAllTIPModifiers(testDesc + ", Right-Shift keyup", [ ]);
+
+  is(events.length, 10,
+     description + testDesc + " should cause 10 events");
+  checkModifiers(testDesc, events[0], "keydown",  "Shift", "ShiftLeft",  [ "Shift" ]);
+  checkModifiers(testDesc, events[1], "keydown",  "Shift", "ShiftRight", [ "Shift" ]);
+  checkModifiers(testDesc, events[2], "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[3], "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[4], "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[5], "keyup",    "Shift", "ShiftLeft",  [ "Shift" ]);
+  checkModifiers(testDesc, events[6], "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[7], "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[8], "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[9], "keyup",    "Shift", "ShiftRight",  [ ]);
+
+  testDesc = "ShiftLeft press -> virtual Shift press -> virtual Shift release -> ShiftLeft release";
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  TIP.keydown(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keydown", [ "Shift" ]);
+  TIP.keydown(shiftVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-Shift keydown", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ "Shift" ]);
+  TIP.keyup(shiftVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-Shift keyup", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Virtual-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Virtual-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keyup", [ ]);
+
+  is(events.length, 10,
+     description + testDesc + " should cause 10 events");
+  checkModifiers(testDesc, events[0], "keydown",  "Shift", "ShiftLeft",  [ "Shift" ]);
+  checkModifiers(testDesc, events[1], "keydown",  "Shift", "",           [ "Shift" ]);
+  checkModifiers(testDesc, events[2], "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[3], "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[4], "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[5], "keyup",    "Shift", "",           [ "Shift" ]);
+  checkModifiers(testDesc, events[6], "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[7], "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[8], "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[9], "keyup",    "Shift", "ShiftLeft",  [ ]);
+
+  testDesc = "virtual Shift press -> ShiftRight press -> ShiftRight release -> virtual Shift release";
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  TIP.keydown(shiftVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-Shift keydown", [ "Shift" ]);
+  TIP.keydown(shiftRight);
+  checkAllTIPModifiers(testDesc + ", Right-Shift keydown", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ "Shift" ]);
+  TIP.keyup(shiftRight);
+  checkAllTIPModifiers(testDesc + ", Right-Shift keyup", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Right-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Right-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(shiftVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-Shift keyup", [ ]);
+
+  is(events.length, 10,
+     description + testDesc + " should cause 10 events");
+  checkModifiers(testDesc, events[0], "keydown",  "Shift", "",           [ "Shift" ]);
+  checkModifiers(testDesc, events[1], "keydown",  "Shift", "ShiftRight", [ "Shift" ]);
+  checkModifiers(testDesc, events[2], "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[3], "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[4], "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[5], "keyup",    "Shift", "ShiftRight", [ "Shift" ]);
+  checkModifiers(testDesc, events[6], "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[7], "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[8], "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[9], "keyup",    "Shift", "",           [ ]);
+
+  testDesc = "ShiftLeft press -> ShiftRight press -> ShiftRight release -> ShiftRight release -> ShiftLeft release";
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  TIP.keydown(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keydown", [ "Shift" ]);
+  TIP.keydown(shiftRight);
+  checkAllTIPModifiers(testDesc + ", Right-Shift keydown", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ "Shift" ]);
+  TIP.keyup(shiftRight);
+  checkAllTIPModifiers(testDesc + ", Right-Shift keyup", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Virtual-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Virtual-Shift keyup)", [ "Shift" ]);
+  TIP.keyup(shiftRight);
+  checkAllTIPModifiers(testDesc + ", Right-Shift keyup again", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Virtual-Shift keyup again)", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Virtual-Shift keyup again)", [ "Shift" ]);
+  TIP.keyup(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keyup", [ ]);
+
+  is(events.length, 14,
+     description + testDesc + " should cause 14 events");
+  checkModifiers(testDesc, events[0],  "keydown",  "Shift", "ShiftLeft",  [ "Shift" ]);
+  checkModifiers(testDesc, events[1],  "keydown",  "Shift", "ShiftRight", [ "Shift" ]);
+  checkModifiers(testDesc, events[2],  "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[3],  "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[4],  "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[5],  "keyup",    "Shift", "ShiftRight", [ "Shift" ]);
+  checkModifiers(testDesc, events[6],  "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[7],  "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[8],  "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[9],  "keyup",    "Shift", "ShiftRight", [ "Shift" ]);
+  checkModifiers(testDesc, events[10], "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[11], "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[12], "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[13], "keyup",    "Shift", "ShiftLeft",  [ ]);
+
+  testDesc = "ShiftLeft press -> ShiftLeft press -> ShiftLeft release -> ShiftLeft release";
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  TIP.keydown(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keydown", [ "Shift" ]);
+  TIP.keydown(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keydown again", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ "Shift" ]);
+  TIP.keyup(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keyup", [ ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Left-Shift keyup)", [ ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Left-Shift keyup)", [ ]);
+  TIP.keyup(shiftLeft);
+  checkAllTIPModifiers(testDesc + ", Left-Shift keyup again", [ ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Left-Shift keyup again)", [ ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Left-Shift keyup again)", [ ]);
+
+  is(events.length, 13,
+     description + testDesc + " should cause 13 events");
+  checkModifiers(testDesc, events[0],  "keydown",  "Shift", "ShiftLeft",  [ "Shift" ]);
+  checkModifiers(testDesc, events[1],  "keydown",  "Shift", "ShiftLeft",  [ "Shift" ]);
+  checkModifiers(testDesc, events[2],  "keydown",  "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[3],  "keypress", "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[4],  "keyup",    "a",     "KeyA",       [ "Shift" ]);
+  checkModifiers(testDesc, events[5],  "keyup",    "Shift", "ShiftLeft",  [ ]);
+  checkModifiers(testDesc, events[6],  "keydown",  "a",     "KeyA",       [ ]);
+  checkModifiers(testDesc, events[7],  "keypress", "a",     "KeyA",       [ ]);
+  checkModifiers(testDesc, events[8],  "keyup",    "a",     "KeyA",       [ ]);
+  checkModifiers(testDesc, events[9],  "keyup",    "Shift", "ShiftLeft",  [ ]);
+  checkModifiers(testDesc, events[10], "keydown",  "a",     "KeyA",       [ ]);
+  checkModifiers(testDesc, events[11], "keypress", "a",     "KeyA",       [ ]);
+  checkModifiers(testDesc, events[12], "keyup",    "a",     "KeyA",       [ ]);
+
+  testDesc = "virtual Shift press -> virtual AltGraph press -> virtual AltGraph release -> virtual Shift release";
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  TIP.keydown(shiftVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-Shift keydown", [ "Shift" ]);
+  TIP.keydown(altGrVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-AltGraph keydown", [ "Shift", "AltGraph" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ "Shift", "AltGraph" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ "Shift", "AltGraph" ]);
+  TIP.keyup(altGrVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-AltGraph keyup", [ "Shift" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Virtual-AltGraph keyup)", [ "Shift" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Virtual-AltGraph keyup)", [ "Shift" ]);
+  TIP.keyup(shiftVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-Shift keyup", [ ]);
+
+  is(events.length, 10,
+     description + testDesc + " should cause 10 events");
+  checkModifiers(testDesc, events[0], "keydown",  "Shift",    "",     [ "Shift" ]);
+  checkModifiers(testDesc, events[1], "keydown",  "AltGraph", "",     [ "Shift", "AltGraph" ]);
+  checkModifiers(testDesc, events[2], "keydown",  "a",        "KeyA", [ "Shift", "AltGraph" ]);
+  checkModifiers(testDesc, events[3], "keypress", "a",        "KeyA", [ "Shift", "AltGraph" ]);
+  checkModifiers(testDesc, events[4], "keyup",    "a",        "KeyA", [ "Shift", "AltGraph" ]);
+  checkModifiers(testDesc, events[5], "keyup",    "AltGraph", "",     [ "Shift" ]);
+  checkModifiers(testDesc, events[6], "keydown",  "a",        "KeyA", [ "Shift" ]);
+  checkModifiers(testDesc, events[7], "keypress", "a",        "KeyA", [ "Shift" ]);
+  checkModifiers(testDesc, events[8], "keyup",    "a",        "KeyA", [ "Shift" ]);
+  checkModifiers(testDesc, events[9], "keyup",    "Shift",    "",     [ ]);
+
+  testDesc = "virtual Shift press -> virtual AltGraph press -> virtual Shift release -> virtual AltGr release";
+  reset();
+  doPreventDefaults = [ "keypress" ];
+  TIP.keydown(shiftVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-Shift keydown", [ "Shift" ]);
+  TIP.keydown(altGrVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-AltGraph keydown", [ "Shift", "AltGraph" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown", [ "Shift", "AltGraph" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup", [ "Shift", "AltGraph" ]);
+  TIP.keyup(shiftVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-Shift keyup", [ "AltGraph" ]);
+  TIP.keydown(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keydown (after Virtual-Shift keyup)", [ "AltGraph" ]);
+  TIP.keyup(keyA);
+  checkAllTIPModifiers(testDesc + ", \"a\" keyup (after Virtual-Shift keyup)", [ "AltGraph" ]);
+  TIP.keyup(altGrVirtual);
+  checkAllTIPModifiers(testDesc + ", Virtual-AltGraph keyup", [ ]);
+
+  is(events.length, 10,
+     description + testDesc + " should cause 10 events");
+  checkModifiers(testDesc, events[0], "keydown",  "Shift",    "",     [ "Shift" ]);
+  checkModifiers(testDesc, events[1], "keydown",  "AltGraph", "",     [ "Shift", "AltGraph" ]);
+  checkModifiers(testDesc, events[2], "keydown",  "a",        "KeyA", [ "Shift", "AltGraph" ]);
+  checkModifiers(testDesc, events[3], "keypress", "a",        "KeyA", [ "Shift", "AltGraph" ]);
+  checkModifiers(testDesc, events[4], "keyup",    "a",        "KeyA", [ "Shift", "AltGraph" ]);
+  checkModifiers(testDesc, events[5], "keyup",    "Shift",    "",     [ "AltGraph" ]);
+  checkModifiers(testDesc, events[6], "keydown",  "a",        "KeyA", [ "AltGraph" ]);
+  checkModifiers(testDesc, events[7], "keypress", "a",        "KeyA", [ "AltGraph" ]);
+  checkModifiers(testDesc, events[8], "keyup",    "a",        "KeyA", [ "AltGraph" ]);
+  checkModifiers(testDesc, events[9], "keyup",    "AltGraph", "",     [ ]);
+
+  // shareModifierStateOf(null) should cause resetting the modifier state
+  function checkTIPModifiers(aTestDesc, aTIP, aModifiers)
+  {
+    /* eslint-disable-next-line no-shadow */
+    for (var i = 0; i < kModifiers.length; i++) {
+      is(aTIP.getModifierState(kModifiers[i]), aModifiers.includes(kModifiers[i]),
+         description + aTestDesc + ", aTIP.getModifierState(\"" + kModifiers[i] + "\") returns wrong value");
+    }
+  }
+  TIP.keydown(shiftVirtual);
+  TIP.keydown(altGrVirtual);
+  sharedTIP.shareModifierStateOf(null);
+  checkTIPModifiers("sharedTIP.sharedModifierStateOf(null) shouldn't cause TIP's modifiers reset", TIP, [ "Shift", "AltGraph" ]);
+  checkTIPModifiers("sharedTIP.sharedModifierStateOf(null) should cause sharedTIP modifiers reset", sharedTIP, [ ]);
+
+  // sharedTIP.shareModifierStateOf(null) should be unlinked from TIP.
+  TIP.keydown(ctrlVirtual);
+  checkTIPModifiers("TIP.keydown(ctrlVirtual) should cause TIP's modifiers set", TIP, [ "Shift", "AltGraph", "Control" ]);
+  checkTIPModifiers("TIP.keydown(ctrlVirtual) shouldn't cause sharedTIP modifiers set", sharedTIP, [ ]);
+
+  // beginInputTransactionForTests() shouldn't cause modifier state reset.
+  ok(TIP.beginInputTransactionForTests(otherWindow),
+     description + "TIP.beginInputTransactionForTests(otherWindow) should return true");
+  checkTIPModifiers("TIP.beginInputTransactionForTests(otherWindow) shouldn't cause TIP's modifiers set", TIP, [ "Shift", "AltGraph", "Control" ]);
+  TIP.keyup(shiftLeft);
+  TIP.keyup(altGrVirtual);
+  TIP.keyup(ctrlVirtual);
+  checkTIPModifiers("TIP should keep modifier's physical key state", TIP, [ "Shift" ]);
+  ok(TIP.beginInputTransactionForTests(window),
+     description + "TIP.beginInputTransactionForTests(window) should return true");
+  checkTIPModifiers("TIP.beginInputTransactionForTests(window) shouldn't cause TIP's modifiers set", TIP, [ "Shift" ]);
+  TIP.keyup(shiftVirtual);
+  checkTIPModifiers("TIP should keep modifier's physical key state", TIP, [ ]);
+
+  window.removeEventListener("keydown", handler);
+  window.removeEventListener("keypress", handler);
+  window.removeEventListener("keyup", handler);
+}
+
+function runErrorTests()
+{
+  var description = "runErrorTests(): ";
+
+  var TIP = createTIP();
+  ok(TIP.beginInputTransactionForTests(window),
+     description + "TIP.beginInputTransactionForTests() should succeed");
+
+  input.value = "";
+  input.focus();
+
+  // startComposition() should throw an exception if there is already a composition
+  TIP.startComposition();
+  try {
+    TIP.startComposition();
+    ok(false,
+       description + "startComposition() should fail if it was already called");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_FAILURE"),
+       description + "startComposition() should cause NS_ERROR_FAILURE if there is already composition");
+  } finally {
+    TIP.cancelComposition();
+  }
+
+  // cancelComposition() should throw an exception if there is no composition
+  try {
+    TIP.cancelComposition();
+    ok(false,
+       description + "cancelComposition() should fail if there is no composition");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_FAILURE"),
+       description + "cancelComposition() should cause NS_ERROR_FAILURE if there is no composition");
+  }
+
+  // commitComposition() without commit string should throw an exception if there is no composition
+  try {
+    TIP.commitComposition();
+    ok(false,
+       description + "commitComposition() should fail if there is no composition");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_FAILURE"),
+       description + "commitComposition() should cause NS_ERROR_FAILURE if there is no composition");
+  }
+
+  // commitCompositionWith("") should throw an exception if there is no composition
+  try {
+    TIP.commitCompositionWith("");
+    ok(false,
+       description + "commitCompositionWith(\"\") should fail if there is no composition");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_FAILURE"),
+       description + "commitCompositionWith(\"\") should cause NS_ERROR_FAILURE if there is no composition");
+  }
+
+  // Pending composition string should allow to flush without clause information (for compatibility)
+  try {
+    TIP.setPendingCompositionString("foo");
+    TIP.flushPendingComposition();
+    ok(true,
+       description + "flushPendingComposition() should succeed even if appendClauseToPendingComposition() has never been called");
+    TIP.cancelComposition();
+  } catch (e) {
+    ok(false,
+       description + "flushPendingComposition() shouldn't cause an exception even if appendClauseToPendingComposition() has never been called");
+  }
+
+  // Pending composition string must be filled by clause information
+  try {
+    TIP.setPendingCompositionString("foo");
+    TIP.appendClauseToPendingComposition(2, TIP.ATTR_RAW_CLAUSE);
+    TIP.flushPendingComposition();
+    ok(false,
+       description + "flushPendingComposition() should fail if appendClauseToPendingComposition() doesn't fill all composition string");
+    TIP.cancelComposition();
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "flushPendingComposition() should cause NS_ERROR_ILLEGAL_VALUE if appendClauseToPendingComposition() doesn't fill all composition string");
+  }
+
+  // Pending composition string must not be shorter than appended clause length
+  try {
+    TIP.setPendingCompositionString("foo");
+    TIP.appendClauseToPendingComposition(4, TIP.ATTR_RAW_CLAUSE);
+    TIP.flushPendingComposition();
+    ok(false,
+       description + "flushPendingComposition() should fail if appendClauseToPendingComposition() appends longer clause information");
+    TIP.cancelComposition();
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "flushPendingComposition() should cause NS_ERROR_ILLEGAL_VALUE if appendClauseToPendingComposition() appends longer clause information");
+  }
+
+  // Pending composition must not have clause information with empty string
+  try {
+    TIP.appendClauseToPendingComposition(1, TIP.ATTR_RAW_CLAUSE);
+    TIP.flushPendingComposition();
+    ok(false,
+       description + "flushPendingComposition() should fail if there is a clause with empty string");
+    TIP.cancelComposition();
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "flushPendingComposition() should cause NS_ERROR_ILLEGAL_VALUE if there is a clause with empty string");
+  }
+
+  // Appending a clause whose length is 0 should cause an exception
+  try {
+    TIP.appendClauseToPendingComposition(0, TIP.ATTR_RAW_CLAUSE);
+    ok(false,
+       description + "appendClauseToPendingComposition() should fail if the length is 0");
+    TIP.flushPendingComposition();
+    TIP.cancelComposition();
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "appendClauseToPendingComposition() should cause NS_ERROR_ILLEGAL_VALUE if the length is 0");
+  }
+
+  // Appending a clause whose attribute is invalid should cause an exception
+  try {
+    TIP.setPendingCompositionString("foo");
+    TIP.appendClauseToPendingComposition(3, 0);
+    ok(false,
+       description + "appendClauseToPendingComposition() should fail if the attribute is invalid");
+    TIP.flushPendingComposition();
+    TIP.cancelComposition();
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "appendClauseToPendingComposition() should cause NS_ERROR_ILLEGAL_VALUE if the attribute is invalid");
+  }
+
+  // Setting caret position outside of composition string should cause an exception
+  try {
+    TIP.setPendingCompositionString("foo");
+    TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+    TIP.setCaretInPendingComposition(4);
+    TIP.flushPendingComposition();
+    ok(false,
+       description + "flushPendingComposition() should fail if caret position is out of composition string");
+    TIP.cancelComposition();
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "flushPendingComposition() should cause NS_ERROR_ILLEGAL_VALUE if caret position is out of composition string");
+  }
+
+  // Calling keydown() with a KeyboardEvent initialized with invalid code value should cause an exception.
+  input.value = "";
+  try {
+    let keyInvalidCode = new KeyboardEvent("", { key: "f", code: "InvalidCodeValue", keyCode: KeyboardEvent.DOM_VK_F });
+    TIP.keydown(keyInvalidCode);
+    ok(false,
+       description + "TIP.keydown(keyInvalidCode) should cause throwing an exception because its code value is not registered");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "TIP.keydown(keyInvalidCode) should cause throwing an exception including NS_ERROR_ILLEGAL_VALUE");
+  } finally {
+    is(input.value, "",
+       description + "The input element should not be modified");
+  }
+
+  // Calling keyup() with a KeyboardEvent initialized with invalid code value should cause an exception.
+  input.value = "";
+  try {
+    let keyInvalidCode = new KeyboardEvent("", { key: "f", code: "InvalidCodeValue", keyCode: KeyboardEvent.DOM_VK_F });
+    TIP.keyup(keyInvalidCode);
+    ok(false,
+       description + "TIP.keyup(keyInvalidCode) should cause throwing an exception because its code value is not registered");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "TIP.keyup(keyInvalidCode) should cause throwing an exception including NS_ERROR_ILLEGAL_VALUE");
+  } finally {
+    is(input.value, "",
+       description + "The input element should not be modified");
+  }
+
+  // Calling keydown(KEY_NON_PRINTABLE_KEY) with a KeyboardEvent initialized with non-key name should cause an exception.
+  input.value = "";
+  try {
+    let keyInvalidKey = new KeyboardEvent("", { key: "ESCAPE", code: "Escape", keyCode: KeyboardEvent.DOM_VK_Escape});
+    TIP.keydown(keyInvalidKey, TIP.KEY_NON_PRINTABLE_KEY);
+    ok(false,
+       description + "TIP.keydown(keyInvalidKey, TIP.KEY_NON_PRINTABLE_KEY) should cause throwing an exception because its key value is not registered");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "keydown(keyInvalidKey, TIP.KEY_NON_PRINTABLE_KEY) should cause throwing an exception including NS_ERROR_ILLEGAL_VALUE");
+  } finally {
+    is(input.value, "",
+       description + "The input element should not be modified");
+  }
+
+  // Calling keyup(KEY_NON_PRINTABLE_KEY) with a KeyboardEvent initialized with non-key name should cause an exception.
+  input.value = "";
+  try {
+    let keyInvalidKey = new KeyboardEvent("", { key: "ESCAPE", code: "Escape", keyCode: KeyboardEvent.DOM_VK_Escape});
+    TIP.keydown(keyInvalidKey, TIP.KEY_NON_PRINTABLE_KEY);
+    ok(false,
+       description + "TIP.keyup(keyInvalidKey, TIP.KEY_NON_PRINTABLE_KEY) should cause throwing an exception because its key value is not registered");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "keyup(keyInvalidKey, TIP.KEY_NON_PRINTABLE_KEY) should cause throwing an exception including NS_ERROR_ILLEGAL_VALUE");
+  } finally {
+    is(input.value, "",
+       description + "The input element should not be modified");
+  }
+
+  // KEY_KEEP_KEY_LOCATION_STANDARD flag should be used only when .location is not initialized with non-zero value.
+  try {
+    let keyEvent = new KeyboardEvent("", { code: "Enter", location: KeyboardEvent.DOM_KEY_LOCATION_LEFT });
+    TIP.keydown(keyEvent, TIP.KEY_KEEP_KEY_LOCATION_STANDARD);
+    ok(false,
+       description + "keydown(KEY_KEEP_KEY_LOCATION_STANDARD) should fail if the .location of the key event is initialized with non-zero value");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "keydown(KEY_KEEP_KEY_LOCATION_STANDARD) should cause NS_ERROR_ILLEGAL_VALUE if the .location of the key event is initialized with nonzero value");
+  }
+  try {
+    let keyEvent = new KeyboardEvent("", { code: "Enter", location: KeyboardEvent.DOM_KEY_LOCATION_LEFT });
+    TIP.keyup(keyEvent, TIP.KEY_KEEP_KEY_LOCATION_STANDARD);
+    ok(false,
+       description + "keyup(KEY_KEEP_KEY_LOCATION_STANDARD) should fail if the .location of the key event is initialized with non-zero value");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "keyup(KEY_KEEP_KEY_LOCATION_STANDARD) should cause NS_ERROR_ILLEGAL_VALUE if the .location of the key event is initialized with nonzero value");
+  }
+
+  // KEY_KEEP_KEYCODE_ZERO flag should be used only when .keyCode is not initialized with non-zero value.
+  try {
+    let keyEvent = new KeyboardEvent("", { key: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN });
+    TIP.keydown(keyEvent, TIP.KEY_KEEP_KEYCODE_ZERO);
+    ok(false,
+       description + "keydown(KEY_KEEP_KEYCODE_ZERO) should fail if the .keyCode of the key event is initialized with non-zero value");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "keydown(KEY_KEEP_KEYCODE_ZERO) should cause NS_ERROR_ILLEGAL_VALUE if the .keyCode of the key event is initialized with nonzero value");
+  }
+  try {
+    let keyEvent = new KeyboardEvent("", { key: "Enter", keyCode: KeyboardEvent.DOM_VK_RETURN });
+    TIP.keyup(keyEvent, TIP.KEY_KEEP_KEYCODE_ZERO);
+    ok(false,
+       description + "keyup(KEY_KEEP_KEYCODE_ZERO) should fail if the .keyCode of the key event is initialized with non-zero value");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "keyup(KEY_KEEP_KEYCODE_ZERO) should cause NS_ERROR_ILLEGAL_VALUE if the .keyCode of the key event is initialized with nonzero value");
+  }
+
+  // Specifying KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT with non-modifier key, it should cause an exception.
+  try {
+    let keyEvent = new KeyboardEvent("", { key: "a", code: "ShiftLeft" });
+    TIP.keyup(keyEvent, TIP.KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT);
+    ok(false,
+       description + "keydown(KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT) should fail if the .key value isn't a modifier key");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "keydown(KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT) should cause NS_ERROR_ILLEGAL_VALUE if the .key value isn't a modifier key");
+  }
+  try {
+    let keyEvent = new KeyboardEvent("", { key: "Enter", code: "ShiftLeft" });
+    TIP.keyup(keyEvent, TIP.KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT);
+    ok(false,
+       description + "keydown(KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT) should fail if the .key value isn't a modifier key");
+  } catch (e) {
+    ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+       description + "keydown(KEY_DONT_DISPATCH_MODIFIER_KEY_EVENT) should cause NS_ERROR_ILLEGAL_VALUE if the .key value isn't a modifier key");
+  }
+
+  // The type of key events specified to composition methods should be "" or "keydown".
+  var kKeyEventTypes = [
+    { type: "keydown",   valid: true },
+    { type: "keypress",  valid: false },
+    { type: "keyup",     valid: false },
+    { type: "",          valid: true },
+    { type: "mousedown", valid: false },
+    { type: "foo",       valid: false },
+  ];
+  for (var i = 0; i < kKeyEventTypes[i].length; i++) {
+    var keyEvent =
+      new KeyboardEvent(kKeyEventTypes[i].type, { key: "a", code: "KeyA", keyCode: KeyboardEvent.DOM_VK_A });
+    var testDescription = description + "type=\"" + kKeyEventTypes[i].type + "\", ";
+    try {
+      TIP.startComposition(keyEvent);
+      ok(kKeyEventTypes[i].valid,
+         testDescription + "TIP.startComposition(keyEvent) should not accept the event type");
+      TIP.cancelComposition();
+    } catch (e) {
+      ok(!kKeyEventTypes[i].valid,
+         testDescription + "TIP.startComposition(keyEvent) should not throw an exception for the event type");
+      ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+         testDescription + "TIP.startComposition(keyEvent) should cause NS_ERROR_ILLEGAL_VALUE if the key event type isn't valid");
+    }
+    try {
+      TIP.setPendingCompositionString("foo");
+      TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+      TIP.setCaretInPendingComposition(3);
+      TIP.flushPendingComposition(keyEvent);
+      ok(kKeyEventTypes[i].valid,
+         testDescription + "TIP.flushPendingComposition(keyEvent) should not accept the event type");
+      TIP.cancelComposition();
+    } catch (e) {
+      ok(!kKeyEventTypes[i].valid,
+         testDescription + "TIP.flushPendingComposition(keyEvent) should not throw an exception for the event type");
+      ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+         testDescription + "TIP.flushPendingComposition(keyEvent) should cause NS_ERROR_ILLEGAL_VALUE if the key event type isn't valid");
+    }
+    try {
+      TIP.startComposition();
+      TIP.commitComposition(keyEvent);
+      ok(kKeyEventTypes[i].valid,
+         testDescription + "TIP.commitComposition(keyEvent) should not accept the event type");
+    } catch (e) {
+      ok(!kKeyEventTypes[i].valid,
+         testDescription + "TIP.commitComposition(keyEvent) should not throw an exception for the event type");
+      ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+         testDescription + "TIP.commitComposition(keyEvent) should cause NS_ERROR_ILLEGAL_VALUE if the key event type isn't valid");
+      TIP.cancelComposition();
+    }
+    try {
+      TIP.commitCompositionWith("foo", keyEvent);
+      ok(kKeyEventTypes[i].valid,
+         testDescription + "TIP.commitCompositionWith(\"foo\", keyEvent) should not accept the event type");
+    } catch (e) {
+      ok(!kKeyEventTypes[i].valid,
+         testDescription + "TIP.commitCompositionWith(\"foo\", keyEvent) should not throw an exception for the event type");
+      ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+         testDescription + "TIP.commitCompositionWith(\"foo\", keyEvent) should cause NS_ERROR_ILLEGAL_VALUE if the key event type isn't valid");
+    }
+    try {
+      TIP.startComposition();
+      TIP.cancelComposition(keyEvent);
+      ok(kKeyEventTypes[i].valid,
+         testDescription + "TIP.cancelComposition(keyEvent) should not accept the event type");
+    } catch (e) {
+      ok(!kKeyEventTypes[i].valid,
+         testDescription + "TIP.cancelComposition(keyEvent) should not throw an exception for the event type");
+      ok(e.message.includes("NS_ERROR_ILLEGAL_VALUE"),
+         testDescription + "TIP.cancelComposition(keyEvent) should cause NS_ERROR_ILLEGAL_VALUE if the key event type isn't valid");
+      TIP.cancelComposition();
+    }
+    input.value = "";
+  }
+}
+
+function runCommitCompositionTests()
+{
+  var description = "runCommitCompositionTests(): ";
+
+  var TIP = createTIP();
+  ok(TIP.beginInputTransactionForTests(window),
+     description + "TIP.beginInputTransactionForTests() should succeed");
+
+  input.focus();
+
+  // commitComposition() should commit the composition with the last data.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  TIP.commitComposition();
+  is(input.value, "foo",
+     description + "commitComposition() should commit the composition with the last data");
+
+  // commitCompositionWith("") should commit the composition with empty string.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  TIP.commitCompositionWith("");
+  is(input.value, "",
+     description + "commitCompositionWith(\"\") should commit the composition with empty string");
+
+  function doCommit(aText)
+  {
+    TIP.commitCompositionWith(aText);
+  }
+
+  // doCommit() should commit the composition with the last data.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  doCommit();
+  todo_is(input.value, "foo",
+          description + "doCommit() should commit the composition with the last data");
+
+  // doCommit("") should commit the composition with empty string.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  doCommit("");
+  is(input.value, "",
+     description + "doCommit(\"\") should commit the composition with empty string");
+
+  // doCommit(null) should commit the composition with empty string.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  doCommit(null);
+  is(input.value, "",
+     description + "doCommit(null) should commit the composition with empty string");
+
+  // doCommit(undefined) should commit the composition with the last data.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  doCommit(undefined);
+  todo_is(input.value, "foo",
+          description + "doCommit(undefined) should commit the composition with the last data");
+
+  function doCommitWithNullCheck(aText)
+  {
+    TIP.commitCompositionWith(aText ? aText : "");
+  }
+
+  // doCommitWithNullCheck() should commit the composition with the last data.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  doCommitWithNullCheck();
+  is(input.value, "",
+     description + "doCommitWithNullCheck() should commit the composition with empty string");
+
+  // doCommitWithNullCheck("") should commit the composition with empty string.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  doCommitWithNullCheck("");
+  is(input.value, "",
+     description + "doCommitWithNullCheck(\"\") should commit the composition with empty string");
+
+  // doCommitWithNullCheck(null) should commit the composition with empty string.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  doCommitWithNullCheck(null);
+  is(input.value, "",
+     description + "doCommitWithNullCheck(null) should commit the composition with empty string");
+
+  // doCommitWithNullCheck(undefined) should commit the composition with the last data.
+  input.value = "";
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.setCaretInPendingComposition(3);
+  TIP.flushPendingComposition();
+  doCommitWithNullCheck(undefined);
+  is(input.value, "",
+     description + "doCommitWithNullCheck(undefined) should commit the composition with empty string");
+}
+
+function runUnloadTests1()
+{
+  return new Promise(resolve => {
+    let description = "runUnloadTests1(): ";
+
+    let TIP1 = createTIP();
+    ok(TIP1.beginInputTransactionForTests(childWindow),
+       description + "TIP1.beginInputTransactionForTests() should succeed");
+
+    let oldSrc = iframe.src;
+    let parentWindow = window;
+
+    iframe.addEventListener("load", function (aEvent) {
+      ok(true, description + "dummy page is loaded");
+      childWindow = iframe.contentWindow;
+      textareaInFrame = null;
+      iframe.addEventListener("load", function () {
+        ok(true, description + "old iframe is restored");
+        // And also restore the iframe information with restored contents.
+        childWindow = iframe.contentWindow;
+        textareaInFrame = iframe.contentDocument.getElementById("textarea");
+        SimpleTest.executeSoon(resolve);
+      }, {capture: true, once: true});
+
+      // The composition should be committed internally.  So, another TIP should
+      // be able to steal the rights to using TextEventDispatcher.
+      let TIP2 = createTIP();
+      ok(TIP2.beginInputTransactionForTests(parentWindow),
+         description + "TIP2.beginInputTransactionForTests() should succeed");
+
+      input.focus();
+      input.value = "";
+
+      TIP2.setPendingCompositionString("foo");
+      TIP2.appendClauseToPendingComposition(3, TIP2.ATTR_RAW_CLAUSE);
+      TIP2.setCaretInPendingComposition(3);
+      TIP2.flushPendingComposition();
+      is(input.value, "foo",
+         description + "the input in the parent document should have composition string");
+
+      TIP2.cancelComposition();
+
+      // Restore the old iframe content.
+      iframe.src = oldSrc;
+    }, {capture: true, once: true});
+
+    // Start composition in the iframe.
+    textareaInFrame.value = "";
+    textareaInFrame.focus();
+
+    TIP1.setPendingCompositionString("foo");
+    TIP1.appendClauseToPendingComposition(3, TIP1.ATTR_RAW_CLAUSE);
+    TIP1.setCaretInPendingComposition(3);
+    TIP1.flushPendingComposition();
+    is(textareaInFrame.value, "foo",
+       description + "the textarea in the iframe should have composition string");
+
+    // Load different web page on the frame.
+    iframe.src = "data:text/html,<body>dummy page</body>";
+  });
+}
+
+function runUnloadTests2()
+{
+  return new Promise(resolve => {
+    let description = "runUnloadTests2(): ";
+
+    let TIP = createTIP();
+    ok(TIP.beginInputTransactionForTests(childWindow),
+       description + "TIP.beginInputTransactionForTests() should succeed");
+
+    let oldSrc = iframe.src;
+
+    iframe.addEventListener("load", function (aEvent) {
+      ok(true, description + "dummy page is loaded");
+      childWindow = iframe.contentWindow;
+      textareaInFrame = null;
+      iframe.addEventListener("load", function () {
+        ok(true, description + "old iframe is restored");
+        // And also restore the iframe information with restored contents.
+        childWindow = iframe.contentWindow;
+        textareaInFrame = iframe.contentDocument.getElementById("textarea");
+        SimpleTest.executeSoon(resolve);
+      }, {capture: true, once: true});
+
+      input.focus();
+      input.value = "";
+
+      // TIP should be still available in the same top level widget.
+      TIP.setPendingCompositionString("bar");
+      TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+      TIP.setCaretInPendingComposition(3);
+      TIP.flushPendingComposition();
+      if (input.value == "") {
+        // XXX TextInputProcessor or TextEventDispatcher may have a bug.
+        todo_is(input.value, "bar",
+                description + "the input in the parent document should have composition string");
+      } else {
+        is(input.value, "bar",
+           description + "the input in the parent document should have composition string");
+      }
+
+      TIP.cancelComposition();
+
+      // Restore the old iframe content.
+      iframe.src = oldSrc;
+    }, {capture: true, once: true});
+
+    // Start composition in the iframe.
+    textareaInFrame.value = "";
+    textareaInFrame.focus();
+
+    TIP.setPendingCompositionString("foo");
+    TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+    TIP.setCaretInPendingComposition(3);
+    TIP.flushPendingComposition();
+    is(textareaInFrame.value, "foo",
+       description + "the textarea in the iframe should have composition string");
+
+    // Load different web page on the frame.
+    iframe.src = "data:text/html,<body>dummy page</body>";
+  });
+}
+
+async function runCallbackTests(aForTests)
+{
+  let description = "runCallbackTests(aForTests=" + aForTests + "): ";
+
+  input.value = "";
+  input.focus();
+  input.blur();
+
+  let TIP = createTIP();
+  let notifications = [];
+  let waitingNextNotification;
+  function callback(aTIP, aNotification)
+  {
+    if (aTIP == TIP) {
+      notifications.push(aNotification);
+    }
+    switch (aNotification.type) {
+      case "request-to-commit":
+        aTIP.commitComposition();
+        break;
+      case "request-to-cancel":
+        aTIP.cancelComposition();
+        break;
+    }
+    if (waitingNextNotification) {
+      SimpleTest.executeSoon(waitingNextNotification);
+      waitingNextNotification = undefined;
+    }
+    return true;
+  }
+
+  function dumpUnexpectedNotifications(aExpectedCount)
+  {
+    if (notifications.length <= aExpectedCount) {
+      return;
+    }
+    for (let i = aExpectedCount; i < notifications.length; i++) {
+      ok(false,
+         description + "Unexpected notification: " + notifications[i].type);
+    }
+  }
+
+  function waitUntilNotificationsReceived()
+  {
+    return new Promise(resolve => {
+      if (notifications.length) {
+        SimpleTest.executeSoon(resolve);
+      } else {
+        waitingNextNotification = resolve;
+      }
+    });
+  }
+
+  function checkPositionChangeNotification(aNotification, aDescription)
+  {
+    is(!aNotification || aNotification.type, "notify-position-change",
+       aDescription + " should cause position change notification");
+  }
+
+  function checkSelectionChangeNotification(aNotification, aDescription, aExpected)
+  {
+    is(aNotification.type, "notify-selection-change",
+       aDescription + " should cause selection change notification");
+    if (aNotification.type != "notify-selection-change") {
+      return;
+    }
+    is(aNotification.hasRange, aExpected.hasRange !== false,
+      `${aDescription} should cause selection change notification whose hasRange is ${aExpected.hasRange}`);
+    if (aNotification.hasRange) {
+      is(aNotification.offset, aExpected.offset,
+        `${aDescription} should cause selection change notification whose offset is ${aExpected.offset}`);
+      is(aNotification.text, aExpected.text,
+        `${aDescription} should cause selection change notification whose text is "${aExpected.text}"`);
+      is(aNotification.length, aExpected.text.length,
+        `${aDescription} should cause selection change notification whose length is ${aExpected.text.length}`);
+      is(aNotification.reversed, aExpected.reversed || false,
+        `${aDescription} should cause selection change notification whose reversed is ${aExpected.reversed || false}`);
+    }
+    is(aNotification.collapsed, aExpected.hasRange === false || !aExpected.text.length,
+      `${aDescription} should cause selection change notification whose collapsed is ${aExpected.hasRange === false || !aExpected.text.length}`);
+    is(aNotification.writingMode, aExpected.writingMode || "horizontal-tb",
+      `${aDescription} should cause selection change notification whose writingMode is ${aExpected.writingMode || "horizontal-tb"}`);
+    is(aNotification.causedByComposition, aExpected.causedByComposition || false,
+      `${aDescription} should cause selection change notification whose causedByComposition is ${aExpected.causedByComposition || false}`);
+    is(aNotification.causedBySelectionEvent, aExpected.causedBySelectionEvent || false,
+      `${aDescription} should cause selection change notification whose causedBySelectionEvent is ${aExpected.causedBySelectionEvent || false}`);
+    is(aNotification.occurredDuringComposition, aExpected.occurredDuringComposition || false,
+      `${aDescription} should cause cause selection change notification whose occurredDuringComposition is ${aExpected.occurredDuringComposition || false}`);
+  }
+
+  function checkTextChangeNotification(aNotification, aDescription, aExpected)
+  {
+    is(aNotification.type, "notify-text-change",
+       aDescription + " should cause text change notification");
+    if (aNotification.type != "notify-text-change") {
+      return;
+    }
+    is(aNotification.offset, aExpected.offset,
+       aDescription + " should cause text change notification whose offset is " + aExpected.offset);
+    is(aNotification.removedLength, aExpected.removedLength,
+       aDescription + " should cause text change notification whose removedLength is " + aExpected.removedLength);
+    is(aNotification.addedLength, aExpected.addedLength,
+       aDescription + " should cause text change notification whose addedLength is " + aExpected.addedLength);
+    is(aNotification.causedOnlyByComposition, aExpected.causedOnlyByComposition || false,
+       aDescription + " should cause text change notification whose causedOnlyByComposition is " + (aExpected.causedOnlyByComposition || false));
+    is(aNotification.includingChangesDuringComposition, aExpected.includingChangesDuringComposition || false,
+       aDescription + " should cause text change notification whose includingChangesDuringComposition is " + (aExpected.includingChangesDuringComposition || false));
+    is(aNotification.includingChangesWithoutComposition, typeof aExpected.includingChangesWithoutComposition === "boolean" ? aExpected.includingChangesWithoutComposition : true,
+       aDescription + " should cause text change notification whose includingChangesWithoutComposition is " + (typeof aExpected.includingChangesWithoutComposition === "boolean" ? aExpected.includingChangesWithoutComposition : true));
+  }
+
+  if (aForTests) {
+    TIP.beginInputTransactionForTests(window, callback);
+  } else {
+    TIP.beginInputTransaction(window, callback);
+  }
+
+  notifications = [];
+  input.focus();
+  is(notifications.length, 1,
+     description + "input.focus() should cause a notification");
+  is(notifications[0].type, "notify-focus",
+     description + "input.focus() should cause \"notify-focus\"");
+  dumpUnexpectedNotifications(1);
+
+  notifications = [];
+  input.blur();
+  is(notifications.length, 1,
+     description + "input.blur() should cause a notification");
+  is(notifications[0].type, "notify-blur",
+     description + "input.blur() should cause \"notify-focus\"");
+  dumpUnexpectedNotifications(1);
+
+  input.focus();
+  await waitUntilNotificationsReceived();
+  notifications = [];
+  TIP.setPendingCompositionString("foo");
+  TIP.appendClauseToPendingComposition(3, TIP.ATTR_RAW_CLAUSE);
+  TIP.flushPendingComposition();
+  is(notifications.length, 3,
+     description + "creating composition string 'foo' should cause 3 notifications");
+  checkTextChangeNotification(notifications[0], description + "creating composition string 'foo'",
+                              { offset: 0, removedLength: 0, addedLength: 3,
+                                causedOnlyByComposition: true, includingChangesDuringComposition: false, includingChangesWithoutComposition: false});
+  checkSelectionChangeNotification(notifications[1], description + "creating composition string 'foo'",
+                                   { offset: 3, text: "", causedByComposition: true, occurredDuringComposition: true });
+  checkPositionChangeNotification(notifications[2], description + "creating composition string 'foo'");
+  dumpUnexpectedNotifications(3);
+
+  notifications = [];
+  synthesizeMouseAtCenter(input, {});
+  is(notifications.length, 3,
+     description + "synthesizeMouseAtCenter(input, {}) during composition should cause 3 notifications");
+  is(notifications[0].type, "request-to-commit",
+     description + "synthesizeMouseAtCenter(input, {}) during composition should cause \"request-to-commit\"");
+  checkTextChangeNotification(notifications[1], description + "synthesizeMouseAtCenter(input, {}) during composition",
+                              { offset: 0, removedLength: 3, addedLength: 3,
+                                causedOnlyByComposition: true, includingChangesDuringComposition: false, includingChangesWithoutComposition: false});
+  checkPositionChangeNotification(notifications[2], description + "synthesizeMouseAtCenter(input, {}) during composition");
+  dumpUnexpectedNotifications(3);
+
+  input.focus();
+  await waitUntilNotificationsReceived();
+  notifications = [];
+  // XXX On macOS, window.moveBy() doesn't cause notify-position-change.
+  //     Investigate this later (although, we cannot notify position change to
+  //     native IME on macOS).
+  // Wayland also does not support it.
+  var isWayland = Services.prefs.getBoolPref("widget.wayland.test-workarounds.enabled", false);
+  if (!kIsMac && !isWayland) {
+    window.moveBy(0, 10);
+    await waitUntilNotificationsReceived();
+    is(notifications.length, 1,
+       description + "window.moveBy(0, 10) should cause a notification");
+    checkPositionChangeNotification(notifications[0], description + "window.moveBy(0, 10)");
+    dumpUnexpectedNotifications(1);
+
+    notifications = [];
+    window.moveBy(10, 0);
+    await waitUntilNotificationsReceived();
+    is(notifications.length, 1,
+       description + "window.moveBy(10, 0) should cause a notification");
+    checkPositionChangeNotification(notifications[0], description + "window.moveBy(10, 0)");
+    dumpUnexpectedNotifications(1);
+  }
+
+  input.focus();
+  input.value = "abc"
+  notifications = [];
+  input.selectionStart = input.selectionEnd = 0;
+  await waitUntilNotificationsReceived();
+  notifications = [];
+  let rightArrowKeyEvent =
+    new KeyboardEvent("", { key: "ArrowRight", code: "ArrowRight", keyCode: KeyboardEvent.DOM_VK_RIGHT });
+  TIP.keydown(rightArrowKeyEvent);
+  TIP.keyup(rightArrowKeyEvent);
+  is(notifications.length, 1,
+     description + "ArrowRight key press should cause a notification");
+  checkSelectionChangeNotification(notifications[0], description + "ArrowRight key press", { offset: 1, text: "" });
+  dumpUnexpectedNotifications(1);
+
+  notifications = [];
+  let shiftKeyEvent =
+    new KeyboardEvent("", { key: "Shift", code: "ShiftLeft", keyCode: KeyboardEvent.DOM_VK_SHIFT });
+  let leftArrowKeyEvent =
+    new KeyboardEvent("", { key: "ArrowLeft", code: "ArrowLeft", keyCode: KeyboardEvent.DOM_VK_LEFT });
+  TIP.keydown(shiftKeyEvent);
+  TIP.keydown(leftArrowKeyEvent);
+  TIP.keyup(leftArrowKeyEvent);
+  TIP.keyup(shiftKeyEvent);
+  is(notifications.length, 1,
+     description + "ArrowLeft key press with Shift should cause a notification");
+  checkSelectionChangeNotification(notifications[0], description + "ArrowLeft key press with Shift", { offset: 0, text: "a", reversed: true });
+  dumpUnexpectedNotifications(1);
+
+  TIP.keydown(rightArrowKeyEvent);
+  TIP.keyup(rightArrowKeyEvent);
+  notifications = [];
+  TIP.keydown(shiftKeyEvent);
+  TIP.keydown(rightArrowKeyEvent);
+  TIP.keyup(rightArrowKeyEvent);
+  TIP.keyup(shiftKeyEvent);
+  is(notifications.length, 1,
+     description + "ArrowRight key press with Shift should cause a notification");
+  checkSelectionChangeNotification(notifications[0], description + "ArrowRight key press with Shift", { offset: 1, text: "b" });
+  dumpUnexpectedNotifications(1);
+
+  notifications = [];
+  input.editor.selection.removeAllRanges();
+  await waitUntilNotificationsReceived();
+  is(notifications.length, 1,
+    `${description}Removing all selection ranges should cause a selection change notification`);
+  checkSelectionChangeNotification(
+    notifications[0],
+    `${description}Removing all selection ranges in editor`,
+    { hasRange: false }
+  );
+  dumpUnexpectedNotifications(1);
+
+  notifications = [];
+  let TIP2 = createTIP();
+  if (aForTests) {
+    TIP2.beginInputTransactionForTests(window, callback);
+  } else {
+    TIP2.beginInputTransaction(window, callback);
+  }
+  is(notifications.length, 1,
+     description + "Initializing another TIP should cause a notification");
+  is(notifications[0].type, "notify-end-input-transaction",
+     description + "Initializing another TIP should cause \"notify-detached\"");
+  dumpUnexpectedNotifications(1);
+}
+
+async function runFocusNotificationTestAfterDrop() {
+  const inputs = document.querySelectorAll("input[type=text]");
+  inputs[0].value = "abc";
+  inputs[1].value = "";
+
+  const TIP = createTIP();
+  let notifications = [];
+  function callback(aTIP, aNotification)
+  {
+    if (aTIP != TIP) {
+      return true;
+    }
+    switch (aNotification.type) {
+      case "request-to-commit":
+        aTIP.commitComposition();
+        break;
+      case "request-to-cancel":
+        aTIP.cancelComposition();
+        break;
+      case "notify-focus":
+      case "notify-blur":
+        notifications.push(aNotification.type);
+        break;
+    }
+    return true;
+  }
+
+  inputs[0].focus();
+  TIP.beginInputTransactionForTests(window, callback);
+  inputs[0].select();
+  try {
+    notifications = [];
+    await synthesizePlainDragAndDrop({
+      srcSelection: SpecialPowers.wrap(inputs[0]).editor.selection,
+      destElement: inputs[1],
+    });
+  } catch (ex) {
+    ok(false, `runFocusNotificationTestAfterDrop: unexpected error during DnD (${ex.message})`);
+    return;
+  }
+  is(
+    document.activeElement,
+    inputs[1],
+    "runFocusNotificationTestAfterDrop: Dropping to the second <input> should make it focused"
+  );
+  ok(
+    notifications.length > 1,
+    "runFocusNotificationTestAfterDrop: At least two notifications should be fired"
+  );
+  if (notifications.length) {
+    is(
+      notifications[notifications.length - 1],
+      "notify-focus",
+      "runFocusNotificationTestAfterDrop: focus notification should've been fired at last"
+    );
+  }
+}
+
+async function runQuerySelectionEventTestAtTextChangeNotification() {
+  contenteditable.innerHTML = "<p>abc</p><p>def</p>";
+  contenteditable.focus();
+  // Ensure to send notify-focus from IMEContentObserver
+  await new Promise(
+    resolve => requestAnimationFrame(
+      () => requestAnimationFrame(resolve)
+    )
+  );
+  document.execCommand("selectall");
+  // Ensure to send notify-selection-change from IMEContentObserver
+  await new Promise(
+    resolve => requestAnimationFrame(
+      () => requestAnimationFrame(resolve)
+    )
+  );
+
+  const kTestName = "runQuerySelectionEventTestAtTextChangeNotification";
+  await new Promise(resolve => {
+    const TIP = createTIP();
+    TIP.beginInputTransactionForTests(window, (aTIP, aNotification) => {
+      if (aTIP != TIP) {
+        return true;
+      }
+      switch (aNotification.type) {
+        case "request-to-commit":
+          aTIP.commitComposition();
+          break;
+        case "request-to-cancel":
+          aTIP.cancelComposition();
+          break;
+        case "notify-text-change":
+          const textContent = synthesizeQueryTextContent(0, 100);
+          if (textContent?.text.includes("abc")) {
+            break;  // Different notification which we want to test, wait next one.
+          }
+          ok(
+            textContent?.succeeded,
+            `${kTestName}: query text content should succeed from notify-text-change handler`
+          );
+          const selectedText = synthesizeQuerySelectedText();
+          ok(
+            selectedText?.succeeded,
+            `${kTestName}: query selected text should succeed from notify-text-change handler`
+          );
+          if (textContent?.succeeded && selectedText?.succeeded) {
+            is(
+              selectedText.text,
+              textContent.text,
+              `${kTestName}: selected text should be same as all text`
+            );
+          }
+          resolve();
+          break;
+      }
+      return true;
+    });
+    // TODO: We want to do this  while selection is batched but can flush
+    //       pending notifications, however, I have no idea how to do it.
+    contenteditable.firstChild.remove();
+  });
+}
+
+async function runIMEStateUpdateTests() {
+  const TIP = createTIP();
+  let notifications = [];
+  function callback(aTIP, aNotification)
+  {
+    if (aTIP != TIP) {
+      return true;
+    }
+    switch (aNotification.type) {
+      case "request-to-commit":
+        aTIP.commitComposition();
+        break;
+      case "request-to-cancel":
+        aTIP.cancelComposition();
+        break;
+      case "notify-focus":
+      case "notify-blur":
+        notifications.push(aNotification.type);
+        break;
+    }
+    return true;
+  }
+
+  contenteditable.focus();
+  TIP.beginInputTransactionForTests(window, callback);
+  await new Promise(resolve => requestAnimationFrame(() =>
+    requestAnimationFrame(resolve)
+  )); // wait for flushing pending notifications if there is.
+
+  // run IMEStateManager::UpdateIMEState to disable IME
+  notifications = [];
+  const editor = getHTMLEditor(window);
+  editor.flags |= Ci.nsIEditor.eEditorReadonlyMask;
+  await new Promise(resolve => requestAnimationFrame(() =>
+    requestAnimationFrame(resolve)
+  )); // wait for flush pending notification even if handled asynchronously.
+  is(
+    notifications.length ? notifications[0] : undefined,
+    "notify-blur",
+    "runIMEStateUpdateTests: Making the HTMLEditor readonly should cause a blur notification"
+  );
+  is(
+    notifications.length,
+    1,
+    `runIMEStateUpdateTests: Making the HTMLEditor readonly should not cause any other notifications, but got ${
+      notifications.length > 1 ? notifications[1] : ""
+    } notification`
+  );
+  is(
+    SpecialPowers.getDOMWindowUtils(window)?.IMEStatus,
+    Ci.nsIDOMWindowUtils.IME_STATUS_DISABLED,
+    `runIMEStateUpdateTests: Making the HTMLEditor readonly should make IME disabled`
+  );
+
+  // run IMEStateManager::UpdateIMEState to enable IME
+  notifications = [];
+  editor.flags &= ~Ci.nsIEditor.eEditorReadonlyMask;
+  await new Promise(resolve => requestAnimationFrame(() =>
+    requestAnimationFrame(resolve)
+  )); // wait for flush pending notification even if handled asynchronously.
+  is(
+    notifications.length ? notifications[0] : undefined,
+    "notify-focus",
+    "runIMEStateUpdateTests: Making the HTMLEditor editable should cause a focus notification without blur notification"
+  );
+  is(
+    notifications.length,
+    1,
+    `runIMEStateUpdateTests: Making the HTMLEditor editable should not cause any other notifications, but got ${
+      notifications.length > 1 ? notifications[1] : ""
+    } notification`
+  );
+  is(
+    SpecialPowers.getDOMWindowUtils(window)?.IMEStatus,
+    Ci.nsIDOMWindowUtils.IME_STATUS_ENABLED,
+    `runIMEStateUpdateTests: Making the HTMLEditor readonly should make IME disabled`
+  );
+}
+
+async function runTextNotificationChangesDuringNoFrame() {
+  const TIP = createTIP();
+  let onTextChange;
+  function callback(aTIP, aNotification)
+  {
+    if (aTIP != TIP) {
+      return true;
+    }
+    switch (aNotification.type) {
+      case "request-to-commit":
+        aTIP.commitComposition();
+        break;
+      case "request-to-cancel":
+        aTIP.cancelComposition();
+        break;
+      case "notify-text-change":
+        if (onTextChange) {
+          onTextChange(aNotification);
+        }
+        break;
+    }
+    return true;
+  }
+
+  function promiseTextChangeNotification() {
+    return new Promise(resolve => onTextChange = resolve);
+  }
+
+  function waitForTick() {
+    return new Promise(resolve => requestAnimationFrame(() => requestAnimationFrame(resolve)));
+  }
+
+  input = document.querySelector("input[type=text]");
+  input.focus();
+  TIP.beginInputTransactionForTests(window, callback);
+
+  await (async function test_text_change_notification_for_value_set_during_no_frame() {
+    const description = "runTextNotificationChangesDuringNoFrame: test_text_change_notification_for_value_set_during_no_frame";
+    input.value = "Start";
+    input.style.display = "inline";
+    input.getBoundingClientRect();
+    await waitForTick();
+    const waitNotifications = promiseTextChangeNotification();
+    input.style.display = "block";
+    input.value = "Changed";
+    info(`${description}: waiting for notifications...`);
+    const notification = await waitNotifications;
+    is(
+      notification?.offset,
+      0,
+      `${description}: offset should be 0`
+    );
+    is(
+      notification?.removedLength,
+      "Start".length,
+      `${description}: removedLength should be the length of the old value`
+    );
+    is(
+      notification?.addedLength,
+      "Changed".length,
+      `${description}: addedLength should be the length of the new value`
+    );
+  })();
+
+  await (async function test_text_change_notification_for_multiple_value_set_during_no_frame() {
+    const description = "runTextNotificationChangesDuringNoFrame: test_text_change_notification_for_multiple_value_set_during_no_frame";
+    input.value = "Start";
+    input.style.display = "inline";
+    input.getBoundingClientRect();
+    await waitForTick();
+    const waitNotifications = promiseTextChangeNotification();
+    input.style.display = "block";
+    input.value = "Changed";
+    input.value = "Again!";
+    info(`${description}: waiting for notifications...`);
+    const notification = await waitNotifications;
+    is(
+      notification?.offset,
+      0,
+      `${description}: offset should be 0`
+    );
+    is(
+      notification?.removedLength,
+      "Start".length,
+      `${description}: removedLength should be the length of the old value`
+    );
+    is(
+      notification?.addedLength,
+      "Again!".length,
+      `${description}: addedLength should be the length of the new value`
+    );
+  })();
+
+  await (async function test_text_change_notification_for_value_set_and_typing_character_during_no_frame() {
+    const description = "runTextNotificationChangesDuringNoFrame: test_text_change_notification_for_value_set_and_typing_character_during_no_frame";
+    input.value = "Start";
+    input.style.display = "inline";
+    input.getBoundingClientRect();
+    await waitForTick();
+    const waitNotifications = promiseTextChangeNotification();
+    input.style.display = "block";
+    input.value = "Change";
+    const dKey = new KeyboardEvent("", { code: "KeyD", key: "d", keyCode: KeyboardEvent.DOM_VK_D });
+    TIP.keydown(dKey);
+    TIP.keyup(dKey);
+    info(`${description}: waiting for notifications...`);
+    const notification = await waitNotifications;
+    is(
+      notification?.offset,
+      0,
+      `${description}: offset should be 0`
+    );
+    is(
+      notification?.removedLength,
+      "Start".length,
+      `${description}: removedLength should be the length of the old value`
+    );
+    is(
+      notification?.addedLength,
+      "Change".length,
+      `${description}: addedLength should be the length of the new (set) value`
+    );
+  })();
+
+  input.style.display = "";
+
+  textarea.focus();
+  TIP.beginInputTransaction(window, callback);
+
+  await (async function test_text_change_notification_for_multi_line_value_set_during_no_frame() {
+    const description = "runTextNotificationChangesDuringNoFrame: test_text_change_notification_for_multi_line_value_set_during_no_frame";
+    textarea.value = "Start\n2nd Line";
+    textarea.style.display = "inline";
+    textarea.getBoundingClientRect();
+    await waitForTick();
+    const waitNotifications = promiseTextChangeNotification();
+    textarea.style.display = "block";
+    textarea.value = "Changed\n2nd Line";
+    info(`${description}: waiting for notifications...`);
+    const notification = await waitNotifications;
+    is(
+      notification?.offset,
+      0,
+      `${description}: offset should be 0`
+    );
+    is(
+      notification?.removedLength,
+      getNativeText("Start\n2nd Line").length,
+      `${description}: removedLength should be the length of the old value`
+    );
+    is(
+      notification?.addedLength,
+      getNativeText("Changed\n2nd Line").length,
+      `${description}: addedLength should be the length of the new value`
+    );
+  })();
+
+  textarea.style.display = "";
+}
+
+async function runTests()
+{
+  textareaInFrame = iframe.contentDocument.getElementById("textarea");
+  runBeginInputTransactionMethodTests();
+  runReleaseTests();
+  runCompositionTests();
+  runCompositionWithKeyEventTests();
+  runConsumingKeydownBeforeCompositionTests();
+  await runKeyTests();
+  runErrorTests();
+  runCommitCompositionTests();
+  await runCallbackTests(false);
+  await runCallbackTests(true);
+  await runTextNotificationChangesDuringNoFrame();
+  await runFocusNotificationTestAfterDrop();
+  await runUnloadTests1();
+  await runUnloadTests2();
+  await runQuerySelectionEventTestAtTextChangeNotification();
+  await runIMEStateUpdateTests();
+
+  finish();
+}
+
+]]>
+</script>
+
+</window>
diff --git a/dom/base/test/chrome/window_swapFrameLoaders.xhtml b/dom/base/test/chrome/window_swapFrameLoaders.xhtml
new file mode 100644
index 0000000000..4a38bcc1fc
--- /dev/null
+++ b/dom/base/test/chrome/window_swapFrameLoaders.xhtml
@@ -0,0 +1,223 @@
+<?xml version="1.0"?>
+<?xml-stylesheet type="text/css" href="chrome://global/skin"?>
+<?xml-stylesheet type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1242644
+Test swapFrameLoaders with different frame types and remoteness
+-->
+<window title="Mozilla Bug 1242644"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+
+  <script type="application/javascript"><![CDATA[
+  ["SimpleTest", "SpecialPowers", "info", "is", "ok", "add_task"].forEach(key => {
+    window[key] = window.arguments[0][key];
+  })
+
+  const NS = {
+    xul: "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul",
+    html: "http://www.w3.org/1999/xhtml",
+  }
+
+  const TAG = {
+    xul: "browser",
+    html: "iframe", // mozbrowser
+  }
+
+  const SCENARIOS = [
+    ["xul", "xul"],
+    ["xul", "html"],
+    ["html", "xul"],
+    ["html", "html"],
+    ["xul", "xul", { remote: true }],
+    ["xul", "html", { remote: true }],
+    ["html", "xul", { remote: true }],
+    ["html", "html", { remote: true }],
+    ["xul", "html", { userContextId: 2 }],
+    ["xul", "html", { userContextId: 2, remote: true }],
+  ];
+
+  const HEIGHTS = [
+    200,
+    400
+  ];
+
+  function frameScript() {
+    /* eslint-env mozilla/frame-script */
+    addEventListener("load", function onLoad() {
+      sendAsyncMessage("test:load");
+    }, true);
+  }
+
+  // Watch for loads in new frames
+  window.messageManager.loadFrameScript(`data:,(${frameScript})();`, true);
+
+  function once(target, eventName, useCapture = false) {
+    info("Waiting for event: '" + eventName + "' on " + target + ".");
+
+    return new Promise(resolve => {
+      for (let [add, remove] of [
+        ["addEventListener", "removeEventListener"],
+        ["addMessageListener", "removeMessageListener"],
+      ]) {
+        if ((add in target) && (remove in target)) {
+          target[add](eventName, function onEvent(...aArgs) {
+            info("Got event: '" + eventName + "' on " + target + ".");
+            target[remove](eventName, onEvent, useCapture);
+            resolve(aArgs);
+          }, useCapture);
+          break;
+        }
+      }
+    });
+  }
+
+  async function addFrame(type, options, height) {
+    let remote = options && options.remote;
+    let userContextId = options && options.userContextId;
+    let frame = document.createElementNS(NS[type], TAG[type]);
+    frame.setAttribute("remote", remote);
+    if (remote && type == "xul") {
+      frame.setAttribute("style", "-moz-binding: none;");
+    }
+    if (userContextId) {
+      frame.setAttribute("usercontextid", userContextId);
+    }
+    if (type == "html") {
+      frame.setAttribute("mozbrowser", "true");
+      frame.setAttribute("noisolation", "true");
+      frame.setAttribute("allowfullscreen", "true");
+    } else if (type == "xul") {
+      frame.setAttribute("type", "content");
+    }
+    let src = `data:text/html,<!doctype html>` +
+              `<body style="height:${height}px"/>`;
+    frame.setAttribute("src", src);
+    document.documentElement.appendChild(frame);
+    let mm = frame.frameLoader.messageManager;
+    await once(mm, "test:load");
+    return frame;
+  }
+
+  add_task(async function() {
+    for (let scenario of SCENARIOS) {
+      let [ typeA, typeB, options ] = scenario;
+      let heightA = HEIGHTS[0];
+      info(`Adding frame A, type ${typeA}, options ${JSON.stringify(options)}, height ${heightA}`);
+      let frameA = await addFrame(typeA, options, heightA);
+
+      let heightB = HEIGHTS[1];
+      info(`Adding frame B, type ${typeB}, options ${JSON.stringify(options)}, height ${heightB}`);
+      let frameB = await addFrame(typeB, options, heightB);
+
+      let frameScriptFactory = function(name) {
+        /* eslint-env mozilla/frame-script */
+        return `function() {
+          addMessageListener("ping", function() {
+            sendAsyncMessage("pong", "${name}");
+          });
+          addMessageListener("check-browser-api", function() {
+            let exists = "api" in this;
+            sendAsyncMessage("check-browser-api", {
+              exists,
+              running: exists && !this.api._shuttingDown,
+            });
+          });
+          addEventListener("pagehide", function({ inFrameSwap }) {
+            sendAsyncMessage("pagehide", inFrameSwap);
+          }, {mozSystemGroup: true});
+        }`;
+      }
+
+      // Load frame script into each frame
+      {
+        let mmA = frameA.frameLoader.messageManager;
+        let mmB = frameB.frameLoader.messageManager;
+
+        mmA.loadFrameScript("data:,(" + frameScriptFactory("A") + ")()", false);
+        mmB.loadFrameScript("data:,(" + frameScriptFactory("B") + ")()", false);
+      }
+
+      // Ping before swap
+      {
+        let mmA = frameA.frameLoader.messageManager;
+        let mmB = frameB.frameLoader.messageManager;
+
+        let inflightA = once(mmA, "pong");
+        let inflightB = once(mmB, "pong");
+
+        info("Ping message manager for frame A");
+        mmA.sendAsyncMessage("ping");
+        let [ { data: pongA } ] = await inflightA;
+        is(pongA, "A", "Frame A message manager gets reply A before swap");
+
+        info("Ping message manager for frame B");
+        mmB.sendAsyncMessage("ping");
+        let [ { data: pongB } ] = await inflightB;
+        is(pongB, "B", "Frame B message manager gets reply B before swap");
+      }
+
+      // Ping after swap using message managers acquired before
+      {
+        let mmA = frameA.frameLoader.messageManager;
+        let mmB = frameB.frameLoader.messageManager;
+
+        let pagehideA = once(mmA, "pagehide");
+        let pagehideB = once(mmB, "pagehide");
+
+        info("swapFrameLoaders");
+        frameA.swapFrameLoaders(frameB);
+
+        let [ { data: inFrameSwapA } ] = await pagehideA;
+        ok(inFrameSwapA, "Frame A got pagehide with inFrameSwap: true");
+        let [ { data: inFrameSwapB } ] = await pagehideB;
+        ok(inFrameSwapB, "Frame B got pagehide with inFrameSwap: true");
+
+        let inflightA = once(mmA, "pong");
+        let inflightB = once(mmB, "pong");
+
+        info("Ping message manager for frame A");
+        mmA.sendAsyncMessage("ping");
+        let [ { data: pongA } ] = await inflightA;
+        is(pongA, "B", "Frame A message manager acquired before swap gets reply B after swap");
+
+        info("Ping message manager for frame B");
+        mmB.sendAsyncMessage("ping");
+        let [ { data: pongB } ] = await inflightB;
+        is(pongB, "A", "Frame B message manager acquired before swap gets reply A after swap");
+      }
+
+      // Check height after swap
+      if (frameA.getContentDimensions) {
+        let { height } = await frameA.getContentDimensions();
+        is(height, heightB, "Frame A's content height is 400px after swap");
+      }
+      if (frameB.getContentDimensions) {
+        let { height } = await frameB.getContentDimensions();
+        is(height, heightA, "Frame B's content height is 200px after swap");
+      }
+
+      // Ping after swap using message managers acquired after
+      {
+        let mmA = frameA.frameLoader.messageManager;
+        let mmB = frameB.frameLoader.messageManager;
+
+        let inflightA = once(mmA, "pong");
+        let inflightB = once(mmB, "pong");
+
+        info("Ping message manager for frame A");
+        mmA.sendAsyncMessage("ping");
+        let [ { data: pongA } ] = await inflightA;
+        is(pongA, "B", "Frame A message manager acquired after swap gets reply B after swap");
+
+        info("Ping message manager for frame B");
+        mmB.sendAsyncMessage("ping");
+        let [ { data: pongB } ] = await inflightB;
+        is(pongB, "A", "Frame B message manager acquired after swap gets reply A after swap");
+      }
+
+      frameA.remove();
+      frameB.remove();
+    }
+  });
+  ]]></script>
+</window>