--- a/browser/base/content/test/plugins/browser.ini
+++ b/browser/base/content/test/plugins/browser.ini
@@ -29,17 +29,16 @@ support-files =
   plugin_overlayed.html
   plugin_positioned.html
   plugin_small.html
   plugin_small_2.html
   plugin_syncRemoved.html
   plugin_test.html
   plugin_test2.html
   plugin_test3.html
-  plugin_test_w_src.html
   plugin_two_types.html
   plugin_unknown.html
   plugin_crashCommentAndURL.html
   plugin_zoom.html
 
 [browser_bug743421.js]
 [browser_bug744745.js]
 [browser_bug787619.js]
@@ -71,17 +70,11 @@ skip-if = (os == 'win' && os_version == 
 [browser_plugin_reloading.js]
 [browser_blocklist_content.js]
 skip-if = !e10s
 [browser_globalplugin_crashinfobar.js]
 skip-if = !crashreporter
 [browser_pluginCrashCommentAndURL.js]
 skip-if = !crashreporter
 [browser_pageInfo_plugins.js]
-[browser_pluginplaypreview.js]
-skip-if = e10s # bug 1148827
-[browser_pluginplaypreview2.js]
-skip-if = e10s # bug 1148827
-[browser_pluginplaypreview3.js]
-skip-if = e10s # bug 1148827
 [browser_pluginCrashReportNonDeterminism.js]
 skip-if = !crashreporter || os == 'linux' # Bug 1152811
 

deleted file mode 100644
--- a/browser/base/content/test/plugins/browser_pluginplaypreview.js
+++ /dev/null
@@ -1,317 +0,0 @@
-var rootDir = getRootDirectory(gTestPath);
-const gTestRoot = rootDir;
-
-var gTestBrowser = null;
-var gNextTest = null;
-var gNextTestSkip = 0;
-var gPlayPreviewPluginActualEvents = 0;
-var gPlayPreviewPluginExpectedEvents = 1;
-
-var gPlayPreviewRegistration = null;
-
-function registerPlayPreview(mimeType, targetUrl) {
-
-  function StreamConverterFactory() {}
-  StreamConverterFactory.prototype = {
-    QueryInterface: XPCOMUtils.generateQI([Ci.nsIFactory]),
-    _targetConstructor: null,
-
-    register: function register(targetConstructor) {
-      this._targetConstructor = targetConstructor;
-      var proto = targetConstructor.prototype;
-      var registrar = Components.manager.QueryInterface(Ci.nsIComponentRegistrar);
-      registrar.registerFactory(proto.classID, proto.classDescription,
-                                proto.contractID, this);
-    },
-
-    unregister: function unregister() {
-      var proto = this._targetConstructor.prototype;
-      var registrar = Components.manager.QueryInterface(Ci.nsIComponentRegistrar);
-      registrar.unregisterFactory(proto.classID, this);
-      this._targetConstructor = null;
-    },
-
-    // nsIFactory
-    createInstance: function createInstance(aOuter, iid) {
-      if (aOuter !== null)
-        throw Cr.NS_ERROR_NO_AGGREGATION;
-      return (new (this._targetConstructor)).QueryInterface(iid);
-    },
-
-    // nsIFactory
-    lockFactory: function lockFactory(lock) {
-      // No longer used as of gecko 1.7.
-      throw Cr.NS_ERROR_NOT_IMPLEMENTED;
-    }
-  };
-
-  function OverlayStreamConverter() {}
-  OverlayStreamConverter.prototype = {
-    QueryInterface: XPCOMUtils.generateQI([
-        Ci.nsISupports,
-        Ci.nsIStreamConverter,
-        Ci.nsIStreamListener,
-        Ci.nsIRequestObserver
-    ]),
-
-    classID: Components.ID('{4c6030f7-e20a-264f-0f9b-ada3a9e97384}'),
-    classDescription: 'overlay-test-data Component',
-    contractID: '@mozilla.org/streamconv;1?from=application/x-moz-playpreview&to=*/*',
-
-    // nsIStreamConverter::convert
-    convert: function(aFromStream, aFromType, aToType, aCtxt) {
-      throw Cr.NS_ERROR_NOT_IMPLEMENTED;
-    },
-
-    // nsIStreamConverter::asyncConvertData
-    asyncConvertData: function(aFromType, aToType, aListener, aCtxt) {
-      var isValidRequest = false;
-      try {
-        var request = aCtxt;
-        request.QueryInterface(Ci.nsIChannel);
-        var spec = request.URI.spec;
-        var expectedSpec = 'data:application/x-moz-playpreview;,' + mimeType;
-        isValidRequest = (spec == expectedSpec);
-      } catch (e) { }
-      if (!isValidRequest)
-        throw Cr.NS_ERROR_NOT_IMPLEMENTED;
-
-      // Store the listener passed to us
-      this.listener = aListener;
-    },
-
-    // nsIStreamListener::onDataAvailable
-    onDataAvailable: function(aRequest, aContext, aInputStream, aOffset, aCount) {
-      // Do nothing since all the data loading is handled by the viewer.
-      ok(false, "onDataAvailable should not be called");
-    },
-
-    // nsIRequestObserver::onStartRequest
-    onStartRequest: function(aRequest, aContext) {
-
-      // Setup the request so we can use it below.
-      aRequest.QueryInterface(Ci.nsIChannel);
-      // Cancel the request so the viewer can handle it.
-      aRequest.cancel(Cr.NS_BINDING_ABORTED);
-
-      // Create a new channel that is viewer loaded as a resource.
-      var ioService = Services.io;
-      var channel = ioService.newChannel2(targetUrl,
-                                          null,
-                                          null,
-                                          null,      // aLoadingNode
-                                          Services.scriptSecurityManager.getSystemPrincipal(),
-                                          null,      // aTriggeringPrincipal
-                                          Ci.nsILoadInfo.SEC_NORMAL,
-                                          Ci.nsIContentPolicy.TYPE_OTHER);
-      channel.asyncOpen(this.listener, aContext);
-    },
-
-    // nsIRequestObserver::onStopRequest
-    onStopRequest: function(aRequest, aContext, aStatusCode) {
-      // Do nothing.
-    }
-  };
-
-  var ph = Cc["@mozilla.org/plugin/host;1"].getService(Ci.nsIPluginHost);
-  ph.registerPlayPreviewMimeType(mimeType, true); // ignoring CTP rules
-
-  var factory = new StreamConverterFactory();
-  factory.register(OverlayStreamConverter);
-
-  return (gPlayPreviewRegistration = {
-    unregister: function() {
-      ph.unregisterPlayPreviewMimeType(mimeType);
-      factory.unregister();
-      gPlayPreviewRegistration = null;
-    }
-  });
-}
-
-function unregisterPlayPreview() {
-  gPlayPreviewRegistration.unregister();
-}
-
-Components.utils.import('resource://gre/modules/XPCOMUtils.jsm');
-Components.utils.import("resource://gre/modules/Services.jsm");
-
-
-function test() {
-  waitForExplicitFinish();
-  registerCleanupFunction(function() {
-    if (gPlayPreviewRegistration)
-      gPlayPreviewRegistration.unregister();
-    Services.prefs.clearUserPref("plugins.click_to_play");
-  });
-
-  var newTab = gBrowser.addTab();
-  gBrowser.selectedTab = newTab;
-  gTestBrowser = gBrowser.selectedBrowser;
-  gTestBrowser.addEventListener("load", pageLoad, true);
-  gTestBrowser.addEventListener("PluginBindingAttached", handleBindingAttached, true, true);
-
-  setTestPluginEnabledState(Ci.nsIPluginTag.STATE_ENABLED);
-  registerPlayPreview('application/x-test', 'about:');
-  prepareTest(test1a, gTestRoot + "plugin_test.html", 1);
-}
-
-function finishTest() {
-  gTestBrowser.removeEventListener("load", pageLoad, true);
-  gTestBrowser.removeEventListener("PluginBindingAttached", handleBindingAttached, true, true);
-  gBrowser.removeCurrentTab();
-  window.focus();
-  finish();
-}
-
-function handleBindingAttached(evt) {
-  if (evt.target instanceof Ci.nsIObjectLoadingContent &&
-      evt.target.pluginFallbackType == Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW)
-    gPlayPreviewPluginActualEvents++;
-}
-
-function pageLoad() {
-  // The plugin events are async dispatched and can come after the load event
-  // This just allows the events to fire before we then go on to test the states
-
-  // iframe might triggers load event as well, making sure we skip some to let
-  // all iframes on the page be loaded as well
-  if (gNextTestSkip) {
-    gNextTestSkip--;
-    return;
-  }
-  executeSoon(gNextTest);
-}
-
-function prepareTest(nextTest, url, skip) {
-  gNextTest = nextTest;
-  gNextTestSkip = skip;
-  gTestBrowser.contentWindow.location = url;
-}
-
-// Tests a page with normal play preview registration (1/2)
-function test1a() {
-  var notificationBox = gBrowser.getNotificationBox(gTestBrowser);
-  ok(!notificationBox.getNotificationWithValue("blocked-plugins"), "Test 1a, Should not have displayed the blocked plugin notification");
-
-  var pluginInfo = getTestPlugin();
-  ok(pluginInfo, "Should have a test plugin");
-
-  var doc = gTestBrowser.contentDocument;
-  var plugin = doc.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  is(objLoadingContent.pluginFallbackType, Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW, "Test 1a, plugin fallback type should be PLUGIN_PLAY_PREVIEW");
-  ok(!objLoadingContent.activated, "Test 1a, Plugin should not be activated");
-
-  var overlay = doc.getAnonymousElementByAttribute(plugin, "class", "previewPluginContent");
-  ok(overlay, "Test 1a, the overlay div is expected");
-
-  var iframe = overlay.getElementsByClassName("previewPluginContentFrame")[0];
-  ok(iframe && iframe.localName == "iframe", "Test 1a, the overlay iframe is expected");
-  var iframeHref = iframe.contentWindow.location.href;
-  ok(iframeHref == "about:", "Test 1a, the overlay about: content is expected");
-
-  var rect = iframe.getBoundingClientRect();
-  ok(rect.width == 200, "Test 1a, Plugin with id=" + plugin.id + " overlay rect should have 200px width before being replaced by actual plugin");
-  ok(rect.height == 200, "Test 1a, Plugin with id=" + plugin.id + " overlay rect should have 200px height before being replaced by actual plugin");
-
-  var e = overlay.ownerDocument.createEvent("CustomEvent");
-  e.initCustomEvent("MozPlayPlugin", true, true, null);
-  overlay.dispatchEvent(e);
-  var condition = function() objLoadingContent.activated;
-  waitForCondition(condition, test1b, "Test 1a, Waited too long for plugin to stop play preview");
-}
-
-// Tests that activating via MozPlayPlugin through the notification works (part 2/2)
-function test1b() {
-  var plugin = gTestBrowser.contentDocument.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.activated, "Test 1b, Plugin should be activated");
-
-  is(gPlayPreviewPluginActualEvents, gPlayPreviewPluginExpectedEvents,
-     "There should be exactly one PluginPlayPreview event");
-
-  unregisterPlayPreview();
-
-  prepareTest(test2, gTestRoot + "plugin_test.html");
-}
-
-// Tests a page with a working plugin in it -- the mime type was just unregistered.
-function test2() {
-  var plugin = gTestBrowser.contentDocument.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.activated, "Test 2, Plugin should be activated");
-
-  registerPlayPreview('application/x-unknown', 'about:');
-
-  prepareTest(test3, gTestRoot + "plugin_test.html");
-}
-
-// Tests a page with a working plugin in it -- diffent play preview type is reserved.
-function test3() {
-  var plugin = gTestBrowser.contentDocument.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.activated, "Test 3, Plugin should be activated");
-
-  unregisterPlayPreview();
-
-  registerPlayPreview('application/x-test', 'about:');
-  Services.prefs.setBoolPref("plugins.click_to_play", true);
-  setTestPluginEnabledState(Ci.nsIPluginTag.STATE_CLICKTOPLAY);
-  prepareTest(test4a, gTestRoot + "plugin_test.html", 1);
-}
-
-// Test a fallback to the click-to-play
-function test4a() {
-  var doc = gTestBrowser.contentDocument;
-  var plugin = doc.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  is(objLoadingContent.pluginFallbackType, Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW, "Test 4a, plugin fallback type should be PLUGIN_PLAY_PREVIEW");
-  ok(!objLoadingContent.activated, "Test 4a, Plugin should not be activated");
-
-  var overlay = doc.getAnonymousElementByAttribute(plugin, "class", "previewPluginContent");
-  ok(overlay, "Test 4a, the overlay div is expected");
-
-  var e = overlay.ownerDocument.createEvent("CustomEvent");
-  e.initCustomEvent("MozPlayPlugin", true, true, true);
-  overlay.dispatchEvent(e);
-  var condition = function() objLoadingContent.pluginFallbackType == Ci.nsIObjectLoadingContent.PLUGIN_CLICK_TO_PLAY;
-  waitForCondition(condition, test4b, "Test 4a, Waited too long for plugin to stop play preview");
-}
-
-function test4b() {
-  var doc = gTestBrowser.contentDocument;
-  var plugin = doc.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.pluginFallbackType != Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW, "Test 4b, plugin fallback type should not be PLUGIN_PLAY_PREVIEW");
-  ok(!objLoadingContent.activated, "Test 4b, Plugin should not be activated");
-
-  prepareTest(test5a, gTestRoot + "plugin_test.html", 1);
-}
-
-// Test a bypass of the click-to-play
-function test5a() {
-  var doc = gTestBrowser.contentDocument;
-  var plugin = doc.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  is(objLoadingContent.pluginFallbackType, Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW, "Test 5a, plugin fallback type should be PLUGIN_PLAY_PREVIEW");
-  ok(!objLoadingContent.activated, "Test 5a, Plugin should not be activated");
-
-  var overlay = doc.getAnonymousElementByAttribute(plugin, "class", "previewPluginContent");
-  ok(overlay, "Test 5a, the overlay div is expected");
-
-  var e = overlay.ownerDocument.createEvent("CustomEvent");
-  e.initCustomEvent("MozPlayPlugin", true, true, false);
-  overlay.dispatchEvent(e);
-  var condition = function() objLoadingContent.activated;
-  waitForCondition(condition, test5b, "Test 5a, Waited too long for plugin to stop play preview");
-}
-
-function test5b() {
-  var doc = gTestBrowser.contentDocument;
-  var plugin = doc.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.activated, "Test 5b, Plugin should be activated");
-
-  finishTest();
-}
-

deleted file mode 100644
--- a/browser/base/content/test/plugins/browser_pluginplaypreview2.js
+++ /dev/null
@@ -1,171 +0,0 @@
-var rootDir = getRootDirectory(gTestPath);
-const gTestRoot = rootDir;
-
-var gTestBrowser = null;
-var gNextTest = null;
-var gNextTestSkip = 0;
-var gPlayPreviewPluginActualEvents = 0;
-var gPlayPreviewPluginExpectedEvents = 1;
-
-var gPlayPreviewRegistration = null;
-
-function registerPlayPreview(mimeType, targetUrl) {
-  var ph = Cc["@mozilla.org/plugin/host;1"].getService(Ci.nsIPluginHost);
-  ph.registerPlayPreviewMimeType(mimeType, false, targetUrl);
-
-  return (gPlayPreviewRegistration = {
-    unregister: function() {
-      ph.unregisterPlayPreviewMimeType(mimeType);
-      gPlayPreviewRegistration = null;
-    }
-  });
-}
-
-function unregisterPlayPreview() {
-  gPlayPreviewRegistration.unregister();
-}
-
-Components.utils.import('resource://gre/modules/XPCOMUtils.jsm');
-Components.utils.import("resource://gre/modules/Services.jsm");
-
-
-function test() {
-  waitForExplicitFinish();
-  registerCleanupFunction(function() {
-    if (gPlayPreviewRegistration)
-      gPlayPreviewRegistration.unregister();
-    Services.prefs.clearUserPref("plugins.click_to_play");
-  });
-
-  var newTab = gBrowser.addTab();
-  gBrowser.selectedTab = newTab;
-  gTestBrowser = gBrowser.selectedBrowser;
-  gTestBrowser.addEventListener("load", pageLoad, true);
-  gTestBrowser.addEventListener("PluginBindingAttached", handleBindingAttached, true, true);
-
-  Services.prefs.setBoolPref("plugins.click_to_play", true);
-  setTestPluginEnabledState(Ci.nsIPluginTag.STATE_CLICKTOPLAY);
-
-  registerPlayPreview('application/x-test', 'about:');
-  prepareTest(test1a, gTestRoot + "plugin_test.html", 1);
-}
-
-function finishTest() {
-  gTestBrowser.removeEventListener("load", pageLoad, true);
-  gTestBrowser.removeEventListener("PluginBindingAttached", handleBindingAttached, true, true);
-  gBrowser.removeCurrentTab();
-  window.focus();
-  finish();
-}
-
-function handleBindingAttached(evt) {
-  if (evt.target instanceof Ci.nsIObjectLoadingContent &&
-      evt.target.pluginFallbackType == Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW)
-    gPlayPreviewPluginActualEvents++;
-}
-
-function pageLoad() {
-  // The plugin events are async dispatched and can come after the load event
-  // This just allows the events to fire before we then go on to test the states
-
-  // iframe might triggers load event as well, making sure we skip some to let
-  // all iframes on the page be loaded as well
-  if (gNextTestSkip) {
-    gNextTestSkip--;
-    return;
-  }
-  executeSoon(gNextTest);
-}
-
-function prepareTest(nextTest, url, skip) {
-  gNextTest = nextTest;
-  gNextTestSkip = skip;
-  gTestBrowser.contentWindow.location = url;
-}
-
-// Tests a page with normal play preview registration (1/2)
-function test1a() {
-  var notificationBox = gBrowser.getNotificationBox(gTestBrowser);
-  ok(!notificationBox.getNotificationWithValue("blocked-plugins"), "Test 1a, Should not have displayed the blocked plugin notification");
-
-  var pluginInfo = getTestPlugin();
-  ok(pluginInfo, "Should have a test plugin");
-
-  var doc = gTestBrowser.contentDocument;
-  var plugin = doc.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  is(objLoadingContent.pluginFallbackType, Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW, "Test 1a, plugin fallback type should be PLUGIN_PLAY_PREVIEW");
-  ok(!objLoadingContent.activated, "Test 1a, Plugin should not be activated");
-
-  var overlay = doc.getAnonymousElementByAttribute(plugin, "class", "previewPluginContent");
-  ok(overlay, "Test 1a, the overlay div is expected");
-
-  var iframe = overlay.getElementsByClassName("previewPluginContentFrame")[0];
-  ok(iframe && iframe.localName == "iframe", "Test 1a, the overlay iframe is expected");
-  var iframeHref = iframe.contentWindow.location.href;
-  ok(iframeHref == "about:", "Test 1a, the overlay about: content is expected");
-
-  var rect = iframe.getBoundingClientRect();
-  ok(rect.width == 200, "Test 1a, Plugin with id=" + plugin.id + " overlay rect should have 200px width before being replaced by actual plugin");
-  ok(rect.height == 200, "Test 1a, Plugin with id=" + plugin.id + " overlay rect should have 200px height before being replaced by actual plugin");
-
-  var e = overlay.ownerDocument.createEvent("CustomEvent");
-  e.initCustomEvent("MozPlayPlugin", true, true, null);
-  overlay.dispatchEvent(e);
-  var condition = function() objLoadingContent.activated;
-  waitForCondition(condition, test1b, "Test 1a, Waited too long for plugin to stop play preview");
-}
-
-// Tests that activating via MozPlayPlugin through the notification works (part 2/2)
-function test1b() {
-  var plugin = gTestBrowser.contentDocument.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.activated, "Test 1b, Plugin should be activated");
-
-  is(gPlayPreviewPluginActualEvents, gPlayPreviewPluginExpectedEvents,
-     "There should be exactly one PluginPlayPreview event");
-
-  unregisterPlayPreview();
-
-  prepareTest(test2, gTestRoot + "plugin_test.html");
-}
-
-// Tests a page with a working plugin in it -- the mime type was just unregistered.
-function test2() {
-  var doc = gTestBrowser.contentDocument;
-  var plugin = doc.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.pluginFallbackType != Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW, "Test 2, plugin fallback type should not be PLUGIN_PLAY_PREVIEW");
-  ok(!objLoadingContent.activated, "Test 2, Plugin should not be activated");
-
-  registerPlayPreview('application/x-unknown', 'about:');
-
-  prepareTest(test3, gTestRoot + "plugin_test.html");
-}
-
-// Tests a page with a working plugin in it -- diffent play preview type is reserved.
-function test3() {
-  var doc = gTestBrowser.contentDocument;
-  var plugin = doc.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.pluginFallbackType != Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW, "Test 3, plugin fallback type should not be PLUGIN_PLAY_PREVIEW");
-  ok(!objLoadingContent.activated, "Test 3, Plugin should not be activated");
-
-  unregisterPlayPreview();
-
-  registerPlayPreview('application/x-test', 'about:');
-  Services.prefs.setBoolPref("plugins.click_to_play", false);
-  var plugin = getTestPlugin();
-  plugin.enabledState = Ci.nsIPluginTag.STATE_ENABLED;
-  prepareTest(test4, gTestRoot + "plugin_test.html");
-}
-
-// Tests a page with a working plugin in it -- click-to-play is off
-function test4() {
-  var plugin = gTestBrowser.contentDocument.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.activated, "Test 4, Plugin should be activated");
-
-  finishTest();
-}
-

deleted file mode 100644
--- a/browser/base/content/test/plugins/browser_pluginplaypreview3.js
+++ /dev/null
@@ -1,130 +0,0 @@
-var rootDir = getRootDirectory(gTestPath);
-const gTestRoot = rootDir;
-
-var gTestBrowser = null;
-var gNextTest = null;
-var gNextTestSkip = 0;
-
-var gPlayPreviewRegistration = null;
-
-var gTestPluginType = 'application/x-test';
-var gTestPluginPreviewUrl = 'about:';
-
-function registerPlayPreview(whitelist) {
-  var ph = Cc["@mozilla.org/plugin/host;1"].getService(Ci.nsIPluginHost);
-  ph.registerPlayPreviewMimeType(gTestPluginType, true,
-                                 gTestPluginPreviewUrl, whitelist);
-
-  return (gPlayPreviewRegistration = {
-    unregister: function() {
-      ph.unregisterPlayPreviewMimeType(gTestPluginType);
-      gPlayPreviewRegistration = null;
-    }
-  });
-}
-
-function unregisterPlayPreview() {
-  gPlayPreviewRegistration.unregister();
-}
-
-Components.utils.import('resource://gre/modules/XPCOMUtils.jsm');
-Components.utils.import("resource://gre/modules/Services.jsm");
-
-
-function test() {
-  waitForExplicitFinish();
-  registerCleanupFunction(function() {
-    if (gPlayPreviewRegistration) {
-      gPlayPreviewRegistration.unregister();
-    }
-  });
-
-  var newTab = gBrowser.addTab();
-  gBrowser.selectedTab = newTab;
-  gTestBrowser = gBrowser.selectedBrowser;
-  gTestBrowser.addEventListener("load", pageLoad, true);
-
-  setTestPluginEnabledState(Ci.nsIPluginTag.STATE_ENABLED);
-
-  registerPlayPreview('@*plugin_test.html');
-  prepareTest(test1a, gTestRoot + "plugin_test.html", 1);
-}
-
-function finishTest() {
-  gTestBrowser.removeEventListener("load", pageLoad, true);
-  gBrowser.removeCurrentTab();
-  window.focus();
-  finish();
-}
-
-function pageLoad() {
-  // The plugin events are async dispatched and can come after the load event
-  // This just allows the events to fire before we then go on to test the states
-
-  // iframe might triggers load event as well, making sure we skip some to let
-  // all iframes on the page be loaded as well
-  if (gNextTestSkip) {
-    gNextTestSkip--;
-    return;
-  }
-  executeSoon(gNextTest);
-}
-
-function prepareTest(nextTest, url, skip) {
-  gNextTest = nextTest;
-  gNextTestSkip = skip;
-  gTestBrowser.contentWindow.location = url;
-}
-
-// Tests plugin on a whitelisted page.
-function test1a() {
-  var plugin = gTestBrowser.contentDocument.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  is(objLoadingContent.pluginFallbackType, Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW, "Test 1a, plugin fallback type should be PLUGIN_PLAY_PREVIEW");
-  ok(!objLoadingContent.activated, "Test 1a, Plugin should not be activated");
-
-  unregisterPlayPreview();
-
-  registerPlayPreview('@*plugin_wrong.html');
-  var plugin = getTestPlugin();
-  plugin.enabledState = Ci.nsIPluginTag.STATE_ENABLED;
-  prepareTest(test1b, gTestRoot + "plugin_test.html");
-}
-
-// Tests plugin on a non-whitelisted page.
-function test1b() {
-  var plugin = gTestBrowser.contentDocument.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.activated, "Test 1b, Plugin should be activated");
-
-  unregisterPlayPreview();
-
-  registerPlayPreview('*browser_pluginplaypreview3.js');
-  var plugin = getTestPlugin();
-  plugin.enabledState = Ci.nsIPluginTag.STATE_ENABLED;
-  prepareTest(test2a, gTestRoot + "plugin_test_w_src.html");
-}
-
-// Tests plugin with whitelisted src/data.
-function test2a() {
-  var plugin = gTestBrowser.contentDocument.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(!objLoadingContent.activated, "Test 2a, Plugin should not be activated");
-
-  unregisterPlayPreview();
-
-  registerPlayPreview('*plugin_test_w_src.html');
-  var plugin = getTestPlugin();
-  plugin.enabledState = Ci.nsIPluginTag.STATE_ENABLED;
-  prepareTest(test2b, gTestRoot + "plugin_test_w_src.html");
-}
-
-// Tests plugin with non-whitelisted src/data.
-function test2b() {
-  var plugin = gTestBrowser.contentDocument.getElementById("test");
-  var objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-  ok(objLoadingContent.activated, "Test 2b, Plugin should be activated");
-
-  finishTest();
-}
-

deleted file mode 100644
--- a/browser/base/content/test/plugins/plugin_test_w_src.html
+++ /dev/null
@@ -1,9 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-<meta charset="utf-8">
-</head>
-<body>
-<embed id="test" src="browser_pluginplaypreview3.js" style="width: 200px; height: 200px" type="application/x-test">
-</body>
-</html>

--- a/browser/modules/PluginContent.jsm
+++ b/browser/modules/PluginContent.jsm
@@ -306,18 +306,16 @@ PluginContent.prototype = {
       case Ci.nsIObjectLoadingContent.PLUGIN_OUTDATED:
         return "PluginOutdated";
       case Ci.nsIObjectLoadingContent.PLUGIN_CLICK_TO_PLAY:
         return "PluginClickToPlay";
       case Ci.nsIObjectLoadingContent.PLUGIN_VULNERABLE_UPDATABLE:
         return "PluginVulnerableUpdatable";
       case Ci.nsIObjectLoadingContent.PLUGIN_VULNERABLE_NO_UPDATE:
         return "PluginVulnerableNoUpdate";
-      case Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW:
-        return "PluginPlayPreview";
       default:
         // Not all states map to a handler
         return null;
     }
   },
 
   handleEvent: function (event) {
     let eventType = event.type;
@@ -412,20 +410,16 @@ PluginContent.prototype = {
             eventType == "PluginVulnerableNoUpdate") {
           let vulnerabilityString = gNavigatorBundle.GetStringFromName(eventType);
           let vulnerabilityText = this.getPluginUI(plugin, "vulnerabilityStatus");
           vulnerabilityText.textContent = vulnerabilityString;
         }
         shouldShowNotification = true;
         break;
 
-      case "PluginPlayPreview":
-        this._handlePlayPreviewEvent(plugin);
-        break;
-
       case "PluginDisabled":
         let manageLink = this.getPluginUI(plugin, "managePluginsLink");
         this.addLinkClickCallback(manageLink, "forwardCallback", "managePlugins");
         shouldShowNotification = true;
         break;
 
       case "PluginInstantiated":
         shouldShowNotification = true;
@@ -526,45 +520,28 @@ PluginContent.prototype = {
     let permissionString = pluginHost.getPermissionStringForType(objLoadingContent.actualType);
     let principal = objLoadingContent.ownerDocument.defaultView.top.document.nodePrincipal;
     let pluginPermission = Services.perms.testPermissionFromPrincipal(principal, permissionString);
 
     let isFallbackTypeValid =
       objLoadingContent.pluginFallbackType >= Ci.nsIObjectLoadingContent.PLUGIN_CLICK_TO_PLAY &&
       objLoadingContent.pluginFallbackType <= Ci.nsIObjectLoadingContent.PLUGIN_VULNERABLE_NO_UPDATE;
 
-    if (objLoadingContent.pluginFallbackType == Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW) {
-      // checking if play preview is subject to CTP rules
-      let playPreviewInfo = pluginHost.getPlayPreviewInfo(objLoadingContent.actualType);
-      isFallbackTypeValid = !playPreviewInfo.ignoreCTP;
-    }
-
     return !objLoadingContent.activated &&
            pluginPermission != Ci.nsIPermissionManager.DENY_ACTION &&
            isFallbackTypeValid;
   },
 
   hideClickToPlayOverlay: function (plugin) {
     let overlay = this.getPluginUI(plugin, "main");
     if (overlay) {
       overlay.classList.remove("visible");
     }
   },
 
-  stopPlayPreview: function (plugin, playPlugin) {
-    let objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-    if (objLoadingContent.activated)
-      return;
-
-    if (playPlugin)
-      objLoadingContent.playPlugin();
-    else
-      objLoadingContent.cancelPlayPreview();
-  },
-
   // Forward a link click callback to the chrome process.
   forwardCallback: function (name) {
     this.global.sendAsyncMessage("PluginContent:LinkClickCallback", { name: name });
   },
 
   submitReport: function submitReport(plugin) {
     if (!AppConstants.MOZ_CRASHREPORTER) {
       return;
@@ -636,59 +613,16 @@ PluginContent.prototype = {
         event.button == 0 &&
         event.isTrusted) {
       this._showClickToPlayNotification(plugin, true);
     event.stopPropagation();
     event.preventDefault();
     }
   },
 
-  _handlePlayPreviewEvent: function (plugin) {
-    let doc = plugin.ownerDocument;
-    let pluginHost = Cc["@mozilla.org/plugin/host;1"].getService(Ci.nsIPluginHost);
-    let pluginInfo = this._getPluginInfo(plugin);
-    let playPreviewInfo = pluginHost.getPlayPreviewInfo(pluginInfo.mimetype);
-
-    let previewContent = this.getPluginUI(plugin, "previewPluginContent");
-    let iframe = previewContent.getElementsByClassName("previewPluginContentFrame")[0];
-    if (!iframe) {
-      // lazy initialization of the iframe
-      iframe = doc.createElementNS("http://www.w3.org/1999/xhtml", "iframe");
-      iframe.className = "previewPluginContentFrame";
-      previewContent.appendChild(iframe);
-
-      // Force a style flush, so that we ensure our binding is attached.
-      plugin.clientTop;
-    }
-    iframe.src = playPreviewInfo.redirectURL;
-
-    // MozPlayPlugin event can be dispatched from the extension chrome
-    // code to replace the preview content with the native plugin
-    let playPluginHandler = (event) => {
-      if (!event.isTrusted)
-        return;
-
-      previewContent.removeEventListener("MozPlayPlugin", playPluginHandler, true);
-
-      let playPlugin = !event.detail;
-      this.stopPlayPreview(plugin, playPlugin);
-
-      // cleaning up: removes overlay iframe from the DOM
-      let iframe = previewContent.getElementsByClassName("previewPluginContentFrame")[0];
-      if (iframe)
-        previewContent.removeChild(iframe);
-    };
-
-    previewContent.addEventListener("MozPlayPlugin", playPluginHandler, true);
-
-    if (!playPreviewInfo.ignoreCTP) {
-      this._showClickToPlayNotification(plugin, false);
-    }
-  },
-
   reshowClickToPlayNotification: function () {
     let contentWindow = this.global.content;
     let cwu = contentWindow.QueryInterface(Ci.nsIInterfaceRequestor)
                            .getInterface(Ci.nsIDOMWindowUtils);
     let plugins = cwu.plugins;
     for (let plugin of plugins) {
       let overlay = this.getPluginUI(plugin, "main");
       if (overlay)

--- a/dom/base/nsIObjectLoadingContent.idl
+++ b/dom/base/nsIObjectLoadingContent.idl
@@ -20,17 +20,17 @@ class nsNPAPIPluginInstance;
 
 /**
  * This interface represents a content node that loads objects.
  *
  * Please make sure to update the MozObjectLoadingContent WebIDL
  * interface to mirror this interface when changing it.
  */
 
-[scriptable, uuid(5efbd411-5bbe-4de1-9f3a-1c3459696eb2)]
+[scriptable, uuid(2eb3195e-3eea-4083-bb1d-d2d70fa35ccb)]
 interface nsIObjectLoadingContent : nsISupports
 {
   /**
    * See notes in nsObjectLoadingContent.h
    */
   const unsigned long TYPE_LOADING  = 0;
   const unsigned long TYPE_IMAGE    = 1;
   const unsigned long TYPE_PLUGIN   = 2;
@@ -60,18 +60,16 @@ interface nsIObjectLoadingContent : nsIS
   /// ** Furthermore, values >= PLUGIN_CLICK_TO_PLAY and
   ///    <= PLUGIN_VULNERABLE_NO_UPDATE are click-to-play types.
   // The plugin is disabled until the user clicks on it
   const unsigned long PLUGIN_CLICK_TO_PLAY        = 8;
   // The plugin is vulnerable (update available)
   const unsigned long PLUGIN_VULNERABLE_UPDATABLE = 9;
   // The plugin is vulnerable (no update available)
   const unsigned long PLUGIN_VULNERABLE_NO_UPDATE = 10;
-  // The plugin is in play preview mode
-  const unsigned long PLUGIN_PLAY_PREVIEW         = 11;
 
   /**
    * The actual mime type (the one we got back from the network
    * request) for the element.
    */
   readonly attribute ACString actualType;
 
   /**
@@ -123,33 +121,32 @@ interface nsIObjectLoadingContent : nsIS
    */
   [noscript] void pluginDestroyed();
   [noscript] void pluginCrashed(in nsIPluginTag pluginTag,
                                 in AString pluginDumpID,
                                 in AString browserDumpID,
                                 in boolean submittedCrashReport);
 
   /**
-   * This method will play a plugin that has been stopped by the
-   * click-to-play plugins or play-preview features.
+   * This method will play a plugin that has been stopped by click-to-play.
    */
   void playPlugin();
 
   /**
    * Forces a re-evaluation and reload of the tag, optionally invalidating its
    * click-to-play state.  This can be used when the MIME type that provides a
    * type has changed, for instance, to force the tag to re-evalulate the
    * handler to use.
    */
   void reload(in boolean aClearActivation);
 
   /**
    * This attribute will return true if the current content type has been
    * activated, either explicitly or by passing checks that would have it be
-   * click-to-play or play-preview.
+   * click-to-play.
    */
   readonly attribute boolean activated;
 
   [noscript] void stopPluginInstance();
 
   [noscript] void syncStartPluginInstance();
   [noscript] void asyncStartPluginInstance();
 
@@ -180,20 +177,15 @@ interface nsIObjectLoadingContent : nsIS
 
   /**
    * If this object currently owns a running plugin, regardless of whether or
    * not one is pending spawn/despawn.
    */
   readonly attribute bool hasRunningPlugin;
 
   /**
-   * This method will disable the play-preview plugin state.
-   */
-  void cancelPlayPreview();
-
-  /**
    * If this plugin runs out-of-process, it has a runID to differentiate
    * between different times the plugin process has been instantiated.
    *
    * This throws NS_ERROR_NOT_IMPLEMENTED for in-process plugins.
    */
   readonly attribute unsigned long runID;
 };

--- a/dom/base/nsObjectLoadingContent.cpp
+++ b/dom/base/nsObjectLoadingContent.cpp
@@ -710,17 +710,16 @@ nsObjectLoadingContent::nsObjectLoadingC
   : mType(eType_Loading)
   , mFallbackType(eFallbackAlternate)
   , mRunID(0)
   , mHasRunID(false)
   , mChannelLoaded(false)
   , mInstantiating(false)
   , mNetworkCreated(true)
   , mActivated(false)
-  , mPlayPreviewCanceled(false)
   , mIsStopping(false)
   , mIsLoading(false)
   , mScriptRequested(false) {}
 
 nsObjectLoadingContent::~nsObjectLoadingContent()
 {
   // Should have been unbound from the tree at this point, and
   // CheckPluginStopEvent keeps us alive
@@ -1401,18 +1400,16 @@ nsObjectLoadingContent::ObjectState() co
     case eType_Null:
       switch (mFallbackType) {
         case eFallbackSuppressed:
           return NS_EVENT_STATE_SUPPRESSED;
         case eFallbackUserDisabled:
           return NS_EVENT_STATE_USERDISABLED;
         case eFallbackClickToPlay:
           return NS_EVENT_STATE_TYPE_CLICK_TO_PLAY;
-        case eFallbackPlayPreview:
-          return NS_EVENT_STATE_TYPE_PLAY_PREVIEW;
         case eFallbackDisabled:
           return NS_EVENT_STATE_BROKEN | NS_EVENT_STATE_HANDLER_DISABLED;
         case eFallbackBlocklisted:
           return NS_EVENT_STATE_BROKEN | NS_EVENT_STATE_HANDLER_BLOCKED;
         case eFallbackCrashed:
           return NS_EVENT_STATE_BROKEN | NS_EVENT_STATE_HANDLER_CRASHED;
         case eFallbackUnsupported: {
           // Check to see if plugins are blocked on this platform.
@@ -3117,32 +3114,31 @@ nsObjectLoadingContent::PlayPlugin()
   if (!nsContentUtils::IsCallerChrome())
     return NS_OK;
 
   if (!mActivated) {
     mActivated = true;
     LOG(("OBJLC [%p]: Activated by user", this));
   }
 
-  // If we're in a click-to-play or play preview state, we need to reload
+  // If we're in a click-to-play state, reload.
   // Fallback types >= eFallbackClickToPlay are plugin-replacement types, see
   // header
   if (mType == eType_Null && mFallbackType >= eFallbackClickToPlay) {
     return LoadObject(true, true);
   }
 
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsObjectLoadingContent::Reload(bool aClearActivation)
 {
   if (aClearActivation) {
     mActivated = false;
-    mPlayPreviewCanceled = false;
   }
 
   return LoadObject(true, true);
 }
 
 NS_IMETHODIMP
 nsObjectLoadingContent::GetActivated(bool *aActivated)
 {
@@ -3173,32 +3169,16 @@ NS_IMETHODIMP
 nsObjectLoadingContent::GetHasRunningPlugin(bool *aHasPlugin)
 {
   NS_ENSURE_TRUE(nsContentUtils::IsCallerChrome(), NS_ERROR_NOT_AVAILABLE);
   *aHasPlugin = HasRunningPlugin();
   return NS_OK;
 }
 
 NS_IMETHODIMP
-nsObjectLoadingContent::CancelPlayPreview()
-{
-  if (!nsContentUtils::IsCallerChrome())
-    return NS_ERROR_NOT_AVAILABLE;
-
-  mPlayPreviewCanceled = true;
-
-  // If we're in play preview state already, reload
-  if (mType == eType_Null && mFallbackType == eFallbackPlayPreview) {
-    return LoadObject(true, true);
-  }
-
-  return NS_OK;
-}
-
-NS_IMETHODIMP
 nsObjectLoadingContent::GetRunID(uint32_t* aRunID)
 {
   if (NS_WARN_IF(!nsContentUtils::IsCallerChrome())) {
     return NS_ERROR_NOT_AVAILABLE;
   }
   if (NS_WARN_IF(!aRunID)) {
     return NS_ERROR_INVALID_POINTER;
   }
@@ -3233,52 +3213,25 @@ nsObjectLoadingContent::ShouldPlay(Fallb
     // Plugins running OOP from the chrome process along with plugins running
     // OOP from the content process will hang. Let's prevent that situation.
     aReason = eFallbackDisabled;
     return false;
   }
 
   nsRefPtr<nsPluginHost> pluginHost = nsPluginHost::GetInst();
 
-  nsCOMPtr<nsIPluginPlayPreviewInfo> playPreviewInfo;
-  bool isPlayPreviewSpecified = NS_SUCCEEDED(pluginHost->GetPlayPreviewInfo(
-    mContentType, getter_AddRefs(playPreviewInfo)));
-  if (isPlayPreviewSpecified) {
-    // Checking PlayPreview whitelist as well.
-    nsCString uriSpec, baseSpec;
-    if (mURI) {
-      mURI->GetSpec(uriSpec);
-    }
-    if (mBaseURI) {
-      mBaseURI->GetSpec(baseSpec);
-    }
-    playPreviewInfo->CheckWhitelist(baseSpec, uriSpec, &isPlayPreviewSpecified);
-  }
-  bool ignoreCTP = false;
-  if (isPlayPreviewSpecified) {
-    playPreviewInfo->GetIgnoreCTP(&ignoreCTP);
-  }
-  if (isPlayPreviewSpecified && !mPlayPreviewCanceled &&
-      ignoreCTP) {
-    // play preview in ignoreCTP mode is shown even if the native plugin
-    // is not present/installed
-    aReason = eFallbackPlayPreview;
-    return false;
-  }
   // at this point if it's not a plugin, we let it play/fallback
   if (!aIgnoreCurrentType && mType != eType_Plugin) {
     return true;
   }
 
   // Order of checks:
   // * Assume a default of click-to-play
   // * If globally disabled, per-site permissions cannot override.
   // * If blocklisted, override the reason with the blocklist reason
-  // * If not blocklisted but playPreview, override the reason with the
-  //   playPreview reason.
   // * Check per-site permissions and follow those if specified.
   // * Honor per-plugin disabled permission
   // * Blocklisted plugins are forced to CtP
   // * Check per-plugin permission and follow that.
 
   aReason = eFallbackClickToPlay;
 
   uint32_t enabledState = nsIPluginTag::STATE_DISABLED;
@@ -3304,22 +3257,16 @@ nsObjectLoadingContent::ShouldPlay(Fallb
 
   if (blocklistState == nsIBlocklistService::STATE_VULNERABLE_UPDATE_AVAILABLE) {
     aReason = eFallbackVulnerableUpdatable;
   }
   else if (blocklistState == nsIBlocklistService::STATE_VULNERABLE_NO_UPDATE) {
     aReason = eFallbackVulnerableNoUpdate;
   }
 
-  if (aReason == eFallbackClickToPlay && isPlayPreviewSpecified &&
-      !mPlayPreviewCanceled && !ignoreCTP) {
-    // play preview in click-to-play mode is shown instead of standard CTP UI
-    aReason = eFallbackPlayPreview;
-  }
-
   // Check the permission manager for permission based on the principal of
   // the toplevel content.
 
   nsCOMPtr<nsIContent> thisContent = do_QueryInterface(static_cast<nsIObjectLoadingContent*>(this));
   MOZ_ASSERT(thisContent);
   nsIDocument* ownerDoc = thisContent->OwnerDoc();
 
   nsCOMPtr<nsIDOMWindow> window = ownerDoc->GetWindow();

--- a/dom/base/nsObjectLoadingContent.h
+++ b/dom/base/nsObjectLoadingContent.h
@@ -89,19 +89,16 @@ class nsObjectLoadingContent : public ns
       /// ** Furthermore, values >= eFallbackClickToPlay and
       ///    <= eFallbackVulnerableNoUpdate are click-to-play types.
       // The plugin is disabled until the user clicks on it
       eFallbackClickToPlay = nsIObjectLoadingContent::PLUGIN_CLICK_TO_PLAY,
       // The plugin is vulnerable (update available)
       eFallbackVulnerableUpdatable = nsIObjectLoadingContent::PLUGIN_VULNERABLE_UPDATABLE,
       // The plugin is vulnerable (no update available)
       eFallbackVulnerableNoUpdate = nsIObjectLoadingContent::PLUGIN_VULNERABLE_NO_UPDATE,
-      // The plugin is disabled and play preview content is displayed until
-      // the extension code enables it by sending the MozPlayPlugin event
-      eFallbackPlayPreview = nsIObjectLoadingContent::PLUGIN_PLAY_PREVIEW
     };
 
     nsObjectLoadingContent();
     virtual ~nsObjectLoadingContent();
 
     NS_DECL_NSIREQUESTOBSERVER
     NS_DECL_NSISTREAMLISTENER
     NS_DECL_NSIFRAMELOADEROWNER
@@ -220,20 +217,16 @@ class nsObjectLoadingContent : public ns
     uint32_t PluginFallbackType() const
     {
       return mFallbackType;
     }
     bool HasRunningPlugin() const
     {
       return !!mInstanceOwner;
     }
-    void CancelPlayPreview(mozilla::ErrorResult& aRv)
-    {
-      aRv = CancelPlayPreview();
-    }
     void SwapFrameLoaders(nsXULElement& aOtherOwner, mozilla::ErrorResult& aRv)
     {
       aRv.Throw(NS_ERROR_NOT_IMPLEMENTED);
     }
     void LegacyCall(JSContext* aCx, JS::Handle<JS::Value> aThisVal,
                     const mozilla::dom::Sequence<JS::Value>& aArguments,
                     JS::MutableHandle<JS::Value> aRetval,
                     mozilla::ErrorResult& aRv);
@@ -617,26 +610,23 @@ class nsObjectLoadingContent : public ns
     // created using NS_FROM_PARSER_NETWORK flag. If the element is modified,
     // it may lose the flag.
     bool                        mNetworkCreated : 1;
 
     // Used to keep track of whether or not a plugin has been explicitly
     // activated by PlayPlugin(). (see ShouldPlay())
     bool                        mActivated : 1;
 
-    // Used to keep track of whether or not a plugin is blocked by play-preview.
-    bool                        mPlayPreviewCanceled : 1;
-
     // Protects DoStopPlugin from reentry (bug 724781).
     bool                        mIsStopping : 1;
 
     // Protects LoadObject from re-entry
     bool                        mIsLoading : 1;
 
-    // For plugin stand-in types (click-to-play, play preview, ...) tracks
+    // For plugin stand-in types (click-to-play) tracks
     // whether content js has tried to access the plugin script object.
     bool                        mScriptRequested : 1;
 
     nsWeakFrame                 mPrintFrame;
 
     nsRefPtr<nsPluginInstanceOwner> mInstanceOwner;
     nsTArray<mozilla::dom::MozPluginParameter> mCachedAttributes;
     nsTArray<mozilla::dom::MozPluginParameter> mCachedParameters;

--- a/dom/events/EventStates.h
+++ b/dom/events/EventStates.h
@@ -257,18 +257,16 @@ private:
 // Handler for click to play plugin (vulnerable w/no update)
 #define NS_EVENT_STATE_VULNERABLE_NO_UPDATE NS_DEFINE_EVENT_STATE_MACRO(40)
 // Platform does not support plugin content (some mobile platforms)
 #define NS_EVENT_STATE_TYPE_UNSUPPORTED_PLATFORM NS_DEFINE_EVENT_STATE_MACRO(41)
 // Element is ltr (for :dir pseudo-class)
 #define NS_EVENT_STATE_LTR NS_DEFINE_EVENT_STATE_MACRO(42)
 // Element is rtl (for :dir pseudo-class)
 #define NS_EVENT_STATE_RTL NS_DEFINE_EVENT_STATE_MACRO(43)
-// Handler for play preview plugin
-#define NS_EVENT_STATE_TYPE_PLAY_PREVIEW NS_DEFINE_EVENT_STATE_MACRO(44)
 // Element is highlighted (devtools inspector)
 #define NS_EVENT_STATE_DEVTOOLS_HIGHLIGHTED NS_DEFINE_EVENT_STATE_MACRO(45)
 // Element is an unresolved custom element candidate
 #define NS_EVENT_STATE_UNRESOLVED NS_DEFINE_EVENT_STATE_MACRO(46)
 
 // Event state that is used for values that need to be parsed but do nothing.
 #define NS_EVENT_STATE_IGNORE NS_DEFINE_EVENT_STATE_MACRO(63)
 

--- a/dom/plugins/base/moz.build
+++ b/dom/plugins/base/moz.build
@@ -27,33 +27,31 @@ EXPORTS += [
     'nsJSNPRuntime.h',
     'nsNPAPIPluginInstance.h',
     'nsPluginDirServiceProvider.h',
     'nsPluginHost.h',
     'nsPluginInstanceOwner.h',
     'nsPluginLogging.h',
     'nsPluginNativeWindow.h',
     'nsPluginNativeWindowGtk.h',
-    'nsPluginPlayPreviewInfo.h',
     'nsPluginsCID.h',
     'nsPluginsDir.h',
     'nsPluginTags.h',
 ]
 
 EXPORTS.mozilla += [
     'PluginPRLibrary.h',
 ]
 
 UNIFIED_SOURCES += [
     'nsJSNPRuntime.cpp',
     'nsNPAPIPluginInstance.cpp',
     'nsNPAPIPluginStreamListener.cpp',
     'nsPluginInstanceOwner.cpp',
     'nsPluginModule.cpp',
-    'nsPluginPlayPreviewInfo.cpp',
     'nsPluginStreamListenerPeer.cpp',
     'nsPluginTags.cpp',
     'PluginPRLibrary.cpp',
 ]
 
 SOURCES += [
     'nsNPAPIPlugin.cpp', # Conflict with X11 headers
     'nsPluginHost.cpp',  # Conflict with NS_NPAPIPLUGIN_CALLBACK

--- a/dom/plugins/base/nsIPluginHost.idl
+++ b/dom/plugins/base/nsIPluginHost.idl
@@ -7,41 +7,26 @@
 #include "nsISupports.idl"
 #include "nsIPluginTag.idl"
 
 %{C++
 #define MOZ_PLUGIN_HOST_CONTRACTID \
   "@mozilla.org/plugin/host;1"
 %}
 
-[scriptable, uuid(57069ada-2845-46ef-b57f-233596d1c02c)]
-interface nsIPluginPlayPreviewInfo : nsISupports
-{
-  readonly attribute AUTF8String mimeType;
-  readonly attribute boolean     ignoreCTP;
-  readonly attribute AUTF8String redirectURL;
-  readonly attribute AUTF8String whitelist;
-
-  /**
-   * Checks if pageURI and objectURI matches once of the entries in
-   * the whitelist. If whitelist is empty, returns true. 
-   */
-  boolean checkWhitelist(in AUTF8String pageURI, in AUTF8String objectURI);
-};
-
 [scriptable, function, uuid(9c311778-7c2c-4ad8-b439-b8a2786a20dd)]
 interface nsIClearSiteDataCallback : nsISupports
 {
     /**
      * callback with the result from a call to clearSiteData
      */
     void callback(in nsresult rv);
 };
 
-[scriptable, uuid(0f73bbd2-fc89-41df-b31b-38c09903d187)]
+[scriptable, uuid(f938f5ba-7093-42cd-a559-af8039d99204)]
 interface nsIPluginHost : nsISupports
 {
   /**
    * Causes the plugins directory to be searched again for new plugin
    * libraries.
    */
   void reloadPlugins();
 
@@ -98,37 +83,16 @@ interface nsIPluginHost : nsISupports
    * @param domain: the domain to test. If this argument is null, test if data
    *                is stored for any site. The base domain for the given domain
    *                will be determined; if any data for the base domain or its
    *                subdomains is found, return true.
    */
   boolean siteHasData(in nsIPluginTag plugin, in AUTF8String domain);
 
   /**
-   * Registers the play preview plugin mode for specific mime type
-   *
-   * @param mimeType: specifies plugin mime type.
-   * @param ignoreCTP: if true, the play preview ignores CTP rules, e.g.
-                       whitelisted websites, will not notify about plugin
-                       presence in the address bar.
-   * @param redirectURL: specifies url for the overlay iframe
-   * @param whitelist: specifies plugin whitelist in form of comma separated
-   *                   "[@page_url object_url|@page_url|object_url]" entries,
-   *                    e.g. @http://example.org/* http://example.org/t.swf
-   */
-  void registerPlayPreviewMimeType(in AUTF8String mimeType,
-                                   [optional] in boolean ignoreCTP,
-                                   [optional] in AUTF8String redirectURL,
-                                   [optional] in AUTF8String whitelist);
-
-  void unregisterPlayPreviewMimeType(in AUTF8String mimeType);
-
-  nsIPluginPlayPreviewInfo getPlayPreviewInfo(in AUTF8String mimeType);
-
-  /**
    * Get the "permission string" for the plugin.  This is a string that can be
    * passed to the permission manager to see whether the plugin is allowed to
    * run, for example.  This will typically be based on the plugin's "nice name"
    * and its blocklist state.
    *
    * @mimeType The MIME type we're interested in.
    * @excludeFlags Set of the EXCLUDE_* flags above, defaulting to EXCLUDE_NONE.
    */

--- a/dom/plugins/base/nsPluginHost.cpp
+++ b/dom/plugins/base/nsPluginHost.cpp
@@ -1593,68 +1593,16 @@ nsPluginHost::UnregisterFakePlugin(const
       mFakePlugins.RemoveElementAt(i);
       return NS_OK;
     }
   }
 
   return NS_OK;
 }
 
-NS_IMETHODIMP
-nsPluginHost::RegisterPlayPreviewMimeType(const nsACString& mimeType,
-                                          bool ignoreCTP,
-                                          const nsACString& redirectURL,
-                                          const nsACString& whitelist)
-{
-  nsAutoCString mt(mimeType);
-  nsAutoCString url(redirectURL);
-  if (url.Length() == 0) {
-    // using default play preview iframe URL, if redirectURL is not specified
-    url.AssignLiteral("data:application/x-moz-playpreview;,");
-    url.Append(mimeType);
-  }
-  nsAutoCString wl(whitelist);
-
-  nsRefPtr<nsPluginPlayPreviewInfo> playPreview =
-    new nsPluginPlayPreviewInfo(mt.get(), ignoreCTP, url.get(), wl.get());
-  mPlayPreviewMimeTypes.AppendElement(playPreview);
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPluginHost::UnregisterPlayPreviewMimeType(const nsACString& mimeType)
-{
-  nsAutoCString mimeTypeToRemove(mimeType);
-  for (uint32_t i = mPlayPreviewMimeTypes.Length(); i > 0; i--) {
-    nsRefPtr<nsPluginPlayPreviewInfo> pp = mPlayPreviewMimeTypes[i - 1];
-    if (PL_strcasecmp(pp.get()->mMimeType.get(), mimeTypeToRemove.get()) == 0) {
-      mPlayPreviewMimeTypes.RemoveElementAt(i - 1);
-      break;
-    }
-  }
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPluginHost::GetPlayPreviewInfo(const nsACString& mimeType,
-                                 nsIPluginPlayPreviewInfo** aResult)
-{
-  nsAutoCString mimeTypeToFind(mimeType);
-  for (uint32_t i = 0; i < mPlayPreviewMimeTypes.Length(); i++) {
-    nsRefPtr<nsPluginPlayPreviewInfo> pp = mPlayPreviewMimeTypes[i];
-    if (PL_strcasecmp(pp.get()->mMimeType.get(), mimeTypeToFind.get()) == 0) {
-      *aResult = new nsPluginPlayPreviewInfo(pp.get());
-      NS_ADDREF(*aResult);
-      return NS_OK;
-    }
-  }
-  *aResult = nullptr;
-  return NS_ERROR_NOT_AVAILABLE;
-}
-
 // FIXME-jsplugins Is this method actually needed?
 NS_IMETHODIMP
 nsPluginHost::GetFakePlugin(const nsACString & aMimeType,
                             nsIFakePluginTag** aResult)
 {
   nsRefPtr<nsFakePluginTag> result = FindFakePluginForType(aMimeType, false);
   if (result) {
     result.forget(aResult);

--- a/dom/plugins/base/nsPluginHost.h
+++ b/dom/plugins/base/nsPluginHost.h
@@ -7,17 +7,16 @@
 #define nsPluginHost_h_
 
 #include "nsIPluginHost.h"
 #include "nsIObserver.h"
 #include "nsCOMPtr.h"
 #include "prlink.h"
 #include "prclist.h"
 #include "nsIPluginTag.h"
-#include "nsPluginPlayPreviewInfo.h"
 #include "nsPluginsDir.h"
 #include "nsPluginDirServiceProvider.h"
 #include "nsAutoPtr.h"
 #include "nsWeakPtr.h"
 #include "nsIPrompt.h"
 #include "nsWeakReference.h"
 #include "MainThreadUtils.h"
 #include "nsTArray.h"
@@ -364,17 +363,16 @@ private:
 
   // On certain platforms, we only want to load certain plugins. This function
   // centralizes loading rules.
   bool ShouldAddPlugin(nsPluginTag* aPluginTag);
 
   nsRefPtr<nsPluginTag> mPlugins;
   nsRefPtr<nsPluginTag> mCachedPlugins;
   nsRefPtr<nsInvalidPluginTag> mInvalidPlugins;
-  nsTArray< nsRefPtr<nsPluginPlayPreviewInfo> > mPlayPreviewMimeTypes;
 
   nsTArray< nsRefPtr<nsFakePluginTag> > mFakePlugins;
 
   bool mPluginsLoaded;
 
   // set by pref plugin.override_internal_types
   bool mOverrideInternalTypes;
 

deleted file mode 100644
--- a/dom/plugins/base/nsPluginPlayPreviewInfo.cpp
+++ /dev/null
@@ -1,154 +0,0 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#include "nsPluginPlayPreviewInfo.h"
-#include "nsWildCard.h"
-
-using namespace mozilla;
-
-nsPluginPlayPreviewInfo::nsPluginPlayPreviewInfo(const char* aMimeType,
-                                                 bool aIgnoreCTP,
-                                                 const char* aRedirectURL,
-                                                 const char* aWhitelist)
-  : mMimeType(aMimeType), mIgnoreCTP(aIgnoreCTP), mRedirectURL(aRedirectURL),
-    mWhitelist(aWhitelist) {}
-
-nsPluginPlayPreviewInfo::nsPluginPlayPreviewInfo(
-  const nsPluginPlayPreviewInfo* aSource)
-{
-  MOZ_ASSERT(aSource);
-
-  mMimeType = aSource->mMimeType;
-  mIgnoreCTP = aSource->mIgnoreCTP;
-  mRedirectURL = aSource->mRedirectURL;
-  mWhitelist = aSource->mWhitelist;
-}
-
-nsPluginPlayPreviewInfo::~nsPluginPlayPreviewInfo()
-{
-}
-
-NS_IMPL_ISUPPORTS(nsPluginPlayPreviewInfo, nsIPluginPlayPreviewInfo)
-
-NS_IMETHODIMP
-nsPluginPlayPreviewInfo::GetMimeType(nsACString& aMimeType)
-{
-  aMimeType = mMimeType;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPluginPlayPreviewInfo::GetIgnoreCTP(bool* aIgnoreCTP)
-{
-  *aIgnoreCTP = mIgnoreCTP;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPluginPlayPreviewInfo::GetRedirectURL(nsACString& aRedirectURL)
-{
-  aRedirectURL = mRedirectURL;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPluginPlayPreviewInfo::GetWhitelist(nsACString& aWhitelist)
-{
-  aWhitelist = mWhitelist;
-  return NS_OK;
-}
-
-/* static */ nsresult
-nsPluginPlayPreviewInfo::CheckWhitelist(const nsACString& aPageURI,
-                                        const nsACString& aObjectURI,
-                                        const nsACString& aWhitelist,
-                                        bool *_retval)
-{
-  if (aWhitelist.Length() == 0) {
-    // Considering empty whitelist as '*' entry.
-    *_retval = true;
-    return NS_OK;
-  }
-
-  // Parses whitelist as comma separated entries of
-  //   [@page_url object_url|@page_url|object_url]
-  // where page_url and object_url pattern matches for aPageURI
-  // and aObjectURI, and performs matching as the same time.
-  nsACString::const_iterator start, end;
-  aWhitelist.BeginReading(start);
-  aWhitelist.EndReading(end);
-
-  nsAutoCString pageURI(aPageURI);
-  nsAutoCString objectURI(aObjectURI);
-  nsACString::const_iterator pos = start, entryStart, entryEnd;
-  nsACString::const_iterator pagePatternStart, pagePatternEnd;
-  nsACString::const_iterator objectPatternStart, objectPatternEnd;
-  int matchResult;
-  bool matched, didMatching;
-  while (pos != end) {
-    matched = true;
-    didMatching = false;
-    entryStart = pos;
-    // Looking for end of the entry.
-    while (pos != end && *pos != ',') {
-      pos++;
-    }
-    entryEnd = pos;
-    if (entryStart != entryEnd && *entryStart == '@') {
-      // Pattern for aPageURL is found, finding a space or end of the entry.
-      pagePatternStart = entryStart;
-      pagePatternStart++;
-      pagePatternEnd = pagePatternStart;
-      while (pagePatternEnd != entryEnd && *pagePatternEnd != ' ') {
-        pagePatternEnd++;
-      }
-      nsAutoCString pagePattern(Substring(pagePatternStart, pagePatternEnd));
-      matchResult = NS_WildCardMatch(pageURI.get(), pagePattern.get(), true);
-      matched &= matchResult == MATCH;
-      didMatching = true;
-      objectPatternStart = pagePatternEnd;
-    } else {
-      objectPatternStart = entryStart;
-    }
-    while (objectPatternStart != entryEnd && *objectPatternStart == ' ') {
-      objectPatternStart++;
-    }
-    if (objectPatternStart != entryEnd) {
-      // Pattern for aObjectURL is found, removing trailing spaces.
-      objectPatternEnd = entryEnd;
-      --objectPatternEnd;
-      while (objectPatternStart != objectPatternEnd &&
-             *objectPatternEnd == ' ') {
-        objectPatternEnd--;
-      };
-      objectPatternEnd++;
-      nsAutoCString objectPattern(Substring(objectPatternStart,
-                                            objectPatternEnd));
-      matchResult = NS_WildCardMatch(objectURI.get(), objectPattern.get(), true);
-      matched &= matchResult == MATCH;
-      didMatching = true;
-    }
-    // Ignoring match result for empty entries.
-    if (didMatching && matched) {
-      *_retval = true;
-      return NS_OK;
-    }
-    if (pos == end) {
-      break;
-    }
-    pos++;
-  }
-
-  *_retval = false;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPluginPlayPreviewInfo::CheckWhitelist(const nsACString& aPageURI,
-                                        const nsACString& aObjectURI,
-                                        bool *_retval)
-{
-  return CheckWhitelist(aPageURI, aObjectURI, mWhitelist, _retval);
-}

deleted file mode 100644
--- a/dom/plugins/base/nsPluginPlayPreviewInfo.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#ifndef nsPluginPlayPreviewInfo_h_
-#define nsPluginPlayPreviewInfo_h_
-
-#include "nsString.h"
-#include "nsIPluginHost.h"
-
-class nsPluginPlayPreviewInfo : public nsIPluginPlayPreviewInfo
-{
-  virtual ~nsPluginPlayPreviewInfo();
-
-public:
-   NS_DECL_ISUPPORTS
-   NS_DECL_NSIPLUGINPLAYPREVIEWINFO
-
-  nsPluginPlayPreviewInfo(const char* aMimeType,
-                          bool aIgnoreCTP,
-                          const char* aRedirectURL,
-                          const char* aWhitelist);
-  explicit nsPluginPlayPreviewInfo(const nsPluginPlayPreviewInfo* aSource);
-
-  /** This function checks aPageURI and aObjectURI against the whitelist
-   *  specified in aWhitelist. This is public static function because this
-   *  whitelist checking code needs to be accessed without any instances of
-   *  nsIPluginPlayPreviewInfo. In particular, the Shumway whitelist is
-   *  obtained directly from prefs and compared using this code for telemetry
-   *  purposes.
-   */
-  static nsresult CheckWhitelist(const nsACString& aPageURI,
-                                 const nsACString& aObjectURI,
-                                 const nsACString& aWhitelist,
-                                 bool *_retval);
-
-  nsCString mMimeType;
-  bool      mIgnoreCTP;
-  nsCString mRedirectURL;
-  nsCString mWhitelist;
-};
-
-
-#endif // nsPluginPlayPreviewInfo_h_

--- a/dom/plugins/ipc/PluginInstanceParent.cpp
+++ b/dom/plugins/ipc/PluginInstanceParent.cpp
@@ -162,36 +162,17 @@ PluginInstanceParent::InitMetadata(const
         return false;
     }
     // Ensure that the src attribute is absolute
     nsRefPtr<nsPluginInstanceOwner> owner = GetOwner();
     if (!owner) {
         return false;
     }
     nsCOMPtr<nsIURI> baseUri(owner->GetBaseURI());
-    nsresult rv = NS_MakeAbsoluteURI(mSrcAttribute, aSrcAttribute, baseUri);
-    if (NS_FAILED(rv)) {
-        return false;
-    }
-    // Check the whitelist
-    nsAutoCString baseUrlSpec;
-    rv = baseUri->GetSpec(baseUrlSpec);
-    if (NS_FAILED(rv)) {
-        return false;
-    }
-    auto whitelist = Preferences::GetCString(kShumwayWhitelistPref);
-    // Empty whitelist is interpreted by CheckWhitelist as "allow everything,"
-    // which is not valid for our use case and should be treated as a failure.
-    if (whitelist.IsEmpty()) {
-        return false;
-    }
-    rv = nsPluginPlayPreviewInfo::CheckWhitelist(baseUrlSpec, mSrcAttribute,
-                                                 whitelist,
-                                                 &mIsWhitelistedForShumway);
-    return NS_SUCCEEDED(rv);
+    return NS_SUCCEEDED(NS_MakeAbsoluteURI(mSrcAttribute, aSrcAttribute, baseUri));
 }
 
 void
 PluginInstanceParent::ActorDestroy(ActorDestroyReason why)
 {
 #if defined(OS_WIN)
     if (why == AbnormalShutdown) {
         // If the plugin process crashes, this is the only

--- a/dom/webidl/HTMLObjectElement.webidl
+++ b/dom/webidl/HTMLObjectElement.webidl
@@ -124,19 +124,16 @@ interface MozObjectLoadingContent {
   [ChromeOnly]
   const unsigned long PLUGIN_CLICK_TO_PLAY        = 8;
   // The plugin is vulnerable (update available)
   [ChromeOnly]
   const unsigned long PLUGIN_VULNERABLE_UPDATABLE = 9;
   // The plugin is vulnerable (no update available)
   [ChromeOnly]
   const unsigned long PLUGIN_VULNERABLE_NO_UPDATE = 10;
-  // The plugin is in play preview mode
-  [ChromeOnly]
-  const unsigned long PLUGIN_PLAY_PREVIEW         = 11;
 
   /**
    * The actual mime type (the one we got back from the network
    * request) for the element.
    */
   [ChromeOnly]
   readonly attribute DOMString actualType;
 
@@ -158,35 +155,35 @@ interface MozObjectLoadingContent {
 
   [ChromeOnly]
   sequence<MozPluginParameter> getPluginAttributes();
 
   [ChromeOnly]
   sequence<MozPluginParameter> getPluginParameters();
 
   /**
-   * This method will play a plugin that has been stopped by the
-   * click-to-play plugins or play-preview features.
+   * This method will play a plugin that has been stopped by the click-to-play
+   * feature.
    */
   [ChromeOnly, Throws]
   void playPlugin();
 
   /**
    * Forces a re-evaluation and reload of the tag, optionally invalidating its
    * click-to-play state.  This can be used when the MIME type that provides a
    * type has changed, for instance, to force the tag to re-evalulate the
    * handler to use.
    */
   [ChromeOnly, Throws]
   void reload(boolean aClearActivation);
 
   /**
    * This attribute will return true if the current content type has been
    * activated, either explicitly or by passing checks that would have it be
-   * click-to-play or play-preview.
+   * click-to-play.
    */
   [ChromeOnly]
   readonly attribute boolean activated;
 
   /**
    * The URL of the data/src loaded in the object. This may be null (i.e.
    * an <embed> with no src).
    */
@@ -201,22 +198,16 @@ interface MozObjectLoadingContent {
 
   /**
    * If this object currently owns a running plugin, regardless of whether or
    * not one is pending spawn/despawn.
    */
   [ChromeOnly]
   readonly attribute boolean hasRunningPlugin;
 
-  /**
-   * This method will disable the play-preview plugin state.
-   */
-  [ChromeOnly, Throws]
-  void cancelPlayPreview();
-
   [ChromeOnly, Throws]
   readonly attribute unsigned long runID;
 };
 
 /**
  * Name:Value pair type used for passing parameters to NPAPI or javascript
  * plugins.
  */

--- a/layout/style/nsCSSPseudoClassList.h
+++ b/layout/style/nsCSSPseudoClassList.h
@@ -174,18 +174,16 @@ CSS_STATE_PSEUDO_CLASS(mozSuppressed, ":
                        NS_EVENT_STATE_SUPPRESSED)
 CSS_STATE_PSEUDO_CLASS(mozLoading, ":-moz-loading", 0, "", NS_EVENT_STATE_LOADING)
 CSS_STATE_PSEUDO_CLASS(mozTypeUnsupported, ":-moz-type-unsupported", 0, "",
                        NS_EVENT_STATE_TYPE_UNSUPPORTED)
 CSS_STATE_PSEUDO_CLASS(mozTypeUnsupportedPlatform, ":-moz-type-unsupported-platform", 0, "",
                        NS_EVENT_STATE_TYPE_UNSUPPORTED_PLATFORM)
 CSS_STATE_PSEUDO_CLASS(mozHandlerClickToPlay, ":-moz-handler-clicktoplay", 0, "",
                        NS_EVENT_STATE_TYPE_CLICK_TO_PLAY)
-CSS_STATE_PSEUDO_CLASS(mozHandlerPlayPreview, ":-moz-handler-playpreview", 0, "",
-                       NS_EVENT_STATE_TYPE_PLAY_PREVIEW)
 CSS_STATE_PSEUDO_CLASS(mozHandlerVulnerableUpdatable, ":-moz-handler-vulnerable-updatable", 0, "",
                        NS_EVENT_STATE_VULNERABLE_UPDATABLE)
 CSS_STATE_PSEUDO_CLASS(mozHandlerVulnerableNoUpdate, ":-moz-handler-vulnerable-no-update", 0, "",
                        NS_EVENT_STATE_VULNERABLE_NO_UPDATE)
 CSS_STATE_PSEUDO_CLASS(mozHandlerDisabled, ":-moz-handler-disabled", 0, "",
                        NS_EVENT_STATE_HANDLER_DISABLED)
 CSS_STATE_PSEUDO_CLASS(mozHandlerBlocked, ":-moz-handler-blocked", 0, "",
                        NS_EVENT_STATE_HANDLER_BLOCKED)

--- a/mobile/android/chrome/content/PluginHelper.js
+++ b/mobile/android/chrome/content/PluginHelper.js
@@ -82,27 +82,16 @@ var PluginHelper = {
   },
 
   playPlugin: function(plugin) {
     let objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
     if (!objLoadingContent.activated)
       objLoadingContent.playPlugin();
   },
 
-  stopPlayPreview: function(plugin, playPlugin) {
-    let objLoadingContent = plugin.QueryInterface(Ci.nsIObjectLoadingContent);
-    if (objLoadingContent.activated)
-      return;
-
-    if (playPlugin)
-      objLoadingContent.playPlugin();
-    else
-      objLoadingContent.cancelPlayPreview();
-  },
-
   getPluginPreference: function getPluginPreference() {
     let pluginDisable = Services.prefs.getBoolPref("plugin.disable");
     if (pluginDisable)
       return "0";
 
     let state = Services.prefs.getIntPref("plugin.default.state");
     return state == Ci.nsIPluginTag.STATE_CLICKTOPLAY ? "2" : "1";
   },
@@ -207,64 +196,16 @@ var PluginHelper = {
           if (!PluginHelper.isTooSmall(plugin, overlay)) {
             overlay.classList.add("visible");
           }
         });
 
         break;
       }
 
-      case "PluginPlayPreview": {
-        let previewContent = doc.getAnonymousElementByAttribute(plugin, "class", "previewPluginContent");
-        let pluginHost = Cc["@mozilla.org/plugin/host;1"].getService(Ci.nsIPluginHost);
-        let mimeType = PluginHelper.getPluginMimeType(plugin);
-        let playPreviewInfo = pluginHost.getPlayPreviewInfo(mimeType);
-
-        if (!playPreviewInfo.ignoreCTP) {
-          // Check if plugins have already been activated for this page, or if
-          // the user has set a permission to always play plugins on the site
-          if (aTab.clickToPlayPluginsActivated ||
-              Services.perms.testPermission(aTab.browser.currentURI, "plugins") ==
-              Services.perms.ALLOW_ACTION) {
-            PluginHelper.playPlugin(plugin);
-            return;
-          }
-
-          // Always show door hanger for play preview plugins
-          PluginHelper.delayAndShowDoorHanger(aTab);
-        }
-
-        let iframe = previewContent.getElementsByClassName("previewPluginContentFrame")[0];
-        if (!iframe) {
-          // lazy initialization of the iframe
-          iframe = doc.createElementNS("http://www.w3.org/1999/xhtml", "iframe");
-          iframe.className = "previewPluginContentFrame";
-          previewContent.appendChild(iframe);
-        }
-        iframe.src = playPreviewInfo.redirectURL;
-
-        // MozPlayPlugin event can be dispatched from the extension chrome
-        // code to replace the preview content with the native plugin
-        previewContent.addEventListener("MozPlayPlugin", function playPluginHandler(e) {
-          if (!e.isTrusted)
-            return;
-
-          previewContent.removeEventListener("MozPlayPlugin", playPluginHandler, true);
-
-          let playPlugin = !aEvent.detail;
-          PluginHelper.stopPlayPreview(plugin, playPlugin);
-
-          // cleaning up: removes overlay iframe from the DOM
-          let iframe = previewContent.getElementsByClassName("previewPluginContentFrame")[0];
-          if (iframe)
-            previewContent.removeChild(iframe);
-        }, true);
-        break;
-      }
-
       case "PluginNotFound": {
         // On devices where we don't support Flash, there will be a
         // "Learn More..." link in the missing plugin error message.
         let learnMoreLink = doc.getAnonymousElementByAttribute(plugin, "class", "unsupportedLearnMoreLink");
         let learnMoreUrl = Services.urlFormatter.formatURLPref("app.support.baseURL");
         learnMoreUrl += "mobile-flash-unsupported";
         learnMoreLink.href = learnMoreUrl;
         overlay.classList.add("visible");
@@ -278,16 +219,14 @@ var PluginHelper = {
     if (!(plugin instanceof Ci.nsIObjectLoadingContent))
       return null;
 
     switch (plugin.pluginFallbackType) {
       case Ci.nsIObjectLoadingContent.PLUGIN_UNSUPPORTED:
         return "PluginNotFound";
       case Ci.nsIObjectLoadingContent.PLUGIN_CLICK_TO_PLAY:
         return "PluginClickToPlay";
-      case Ci.nsIObjectLoadingContent.PLUGIN_PLAY_PREVIEW:
-        return "PluginPlayPreview";
       default:
         // Not all states map to a handler
         return null;
     }
   }
 };

--- a/toolkit/mozapps/plugins/content/pluginProblem.xml
+++ b/toolkit/mozapps/plugins/content/pluginProblem.xml
@@ -62,17 +62,16 @@
                     <html:div class="msg msgNotSubmitted">&report.disabled;</html:div>
                     <html:div class="msg msgSubmitFailed">&report.failed;</html:div>
                     <html:div class="msg msgNoCrashReport">&report.unavailable;</html:div>
                 </html:div>
                 <html:div class="msg msgCheckForUpdates"><html:a class="action-link" anonid="checkForUpdatesLink" href="">&checkForUpdates;</html:a></html:div>
             </html:div>
             <html:button class="closeIcon" anonid="closeIcon" title="&hidePluginBtn.label;"/>
         </html:div>
-        <html:div class="previewPluginContent" anonid="previewPluginContent"><!-- iframe and its src will be set at runtime --></html:div>
         <html:div style="display:none;"><children/></html:div>
     </content>
     <implementation>
       <constructor>
         // Notify browser-plugins.js that we were attached, on a delay because
         // this binding doesn't complete layout until the constructor
         // completes.
         this.dispatchEvent(new CustomEvent("PluginBindingAttached"));

--- a/toolkit/mozapps/plugins/content/pluginProblemBinding.css
+++ b/toolkit/mozapps/plugins/content/pluginProblemBinding.css
@@ -3,30 +3,27 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 @namespace url(http://www.w3.org/1999/xhtml); /* set default namespace to HTML */
 
 embed:-moz-handler-disabled,
 embed:-moz-handler-blocked,
 embed:-moz-handler-crashed,
 embed:-moz-handler-clicktoplay,
-embed:-moz-handler-playpreview,
 embed:-moz-handler-vulnerable-updatable,
 embed:-moz-handler-vulnerable-no-update,
 applet:-moz-handler-disabled,
 applet:-moz-handler-blocked,
 applet:-moz-handler-crashed,
 applet:-moz-handler-clicktoplay,
-applet:-moz-handler-playpreview,
 applet:-moz-handler-vulnerable-updatable,
 applet:-moz-handler-vulnerable-no-update,
 object:-moz-handler-disabled,
 object:-moz-handler-blocked,
 object:-moz-handler-crashed,
 object:-moz-handler-clicktoplay,
-object:-moz-handler-playpreview,
 object:-moz-handler-vulnerable-updatable,
 object:-moz-handler-vulnerable-no-update {
     display: inline-block;
     overflow: hidden;
     opacity: 1 !important;
     -moz-binding: url('chrome://mozapps/content/plugins/pluginProblem.xml#pluginProblem') !important;
 }

--- a/toolkit/mozapps/plugins/content/pluginProblemContent.css
+++ b/toolkit/mozapps/plugins/content/pluginProblemContent.css
@@ -66,50 +66,29 @@ html|applet:not([height]), html|applet[h
 .visible > .closeIcon {
   visibility: visible;
 }
 
 .mainBox[chromedir="rtl"] {
   direction: rtl;
 }
 
-:-moz-handler-playpreview .mainBox {
-  display: none;
-}
-
 :-moz-handler-clicktoplay .hoverBox,
 :-moz-handler-vulnerable-updatable .hoverBox,
 :-moz-handler-vulnerable-no-update .hoverBox {
   cursor: pointer;
 }
 
 .hoverBox > label {
   cursor: inherit;
 }
 .icon {
   cursor: inherit;
 }
 
-.previewPluginContent {
-  display: none;
-}
-
-.previewPluginContent > iframe {
-  width: inherit;
-  height: inherit;
-  border: none;
-}
-
-:-moz-handler-playpreview .previewPluginContent {
-  display: block;
-  width: inherit;
-  height: inherit;
-  overflow: hidden;
-}
-
 .msg {
   display: none;
 }
 
 :-moz-type-unsupported .msgUnsupported,
 :-moz-type-unsupported-platform .msgUnsupportedPlatform,
 :-moz-handler-clicktoplay .msgClickToPlay,
 :-moz-handler-vulnerable-updatable .msgVulnerabilityStatus,