move browser to webbrowser/

1 files changed, 0 insertions, 5403 deletions

diff --git a/base/content/tabbrowser.xml b/base/content/tabbrowser.xml
deleted file mode 100644
index b5edd54..0000000
--- a/base/content/tabbrowser.xml
+++ /dev/null
@@ -1,5403 +0,0 @@
-<?xml version="1.0"?>
-
-<!-- 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/. -->
-
-<!DOCTYPE bindings [
-<!ENTITY % tabBrowserDTD SYSTEM "chrome://browser/locale/tabbrowser.dtd" >
-%tabBrowserDTD;
-]>
-
-<bindings id="tabBrowserBindings"
-          xmlns="http://www.mozilla.org/xbl"
-          xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
-          xmlns:xbl="http://www.mozilla.org/xbl">
-
-  <binding id="tabbrowser">
-    <resources>
-      <stylesheet src="chrome://browser/content/tabbrowser.css"/>
-    </resources>
-
-    <content>
-      <xul:stringbundle anonid="tbstringbundle" src="chrome://browser/locale/tabbrowser.properties"/>
-      <xul:tabbox anonid="tabbox" class="tabbrowser-tabbox"
-                  flex="1" eventnode="document" xbl:inherits="handleCtrlPageUpDown"
-                  onselect="if (event.target.localName == 'tabpanels') this.parentNode.updateCurrentBrowser();">
-        <xul:tabpanels flex="1" class="plain" selectedIndex="0" anonid="panelcontainer">
-          <xul:notificationbox flex="1">
-            <xul:hbox flex="1" class="browserSidebarContainer">
-              <xul:vbox flex="1" class="browserContainer">
-                <xul:stack flex="1" class="browserStack" anonid="browserStack">
-                  <xul:browser anonid="initialBrowser" type="content-primary" message="true" disablehistory="true"
-                               xbl:inherits="tooltip=contenttooltip,contextmenu=contentcontextmenu,autocompletepopup,datetimepicker,authdosprotected"/>
-                </xul:stack>
-              </xul:vbox>
-            </xul:hbox>
-          </xul:notificationbox>
-        </xul:tabpanels>
-      </xul:tabbox>
-      <children/>
-    </content>
-    <implementation implements="nsIDOMEventListener, nsIMessageListener">
-
-      <property name="tabContextMenu" readonly="true"
-                onget="return this.tabContainer.contextMenu;"/>
-
-      <field name="tabContainer" readonly="true">
-        document.getElementById(this.getAttribute("tabcontainer"));
-      </field>
-      <field name="tabs" readonly="true">
-        this.tabContainer.childNodes;
-      </field>
-
-      <property name="visibleTabs" readonly="true">
-        <getter><![CDATA[
-          if (!this._visibleTabs)
-            this._visibleTabs = Array.filter(this.tabs,
-                                             function (tab) !tab.hidden && !tab.closing);
-          return this._visibleTabs;
-        ]]></getter>
-      </property>
-
-      <field name="closingTabsEnum" readonly="true">({ ALL: 0, OTHER: 1, TO_END: 2 });</field>
-
-      <field name="_visibleTabs">null</field>
-
-      <field name="mURIFixup" readonly="true">
-        Components.classes["@mozilla.org/docshell/urifixup;1"]
-                  .getService(Components.interfaces.nsIURIFixup);
-      </field>
-      <field name="mFaviconService" readonly="true">
-        Components.classes["@mozilla.org/browser/favicon-service;1"]
-                  .getService(Components.interfaces.nsIFaviconService);
-      </field>
-      <field name="_placesAutocomplete" readonly="true">
-         Components.classes["@mozilla.org/autocomplete/search;1?name=history"]
-                   .getService(Components.interfaces.mozIPlacesAutoComplete);
-      </field>
-      <field name="mTabBox" readonly="true">
-        document.getAnonymousElementByAttribute(this, "anonid", "tabbox");
-      </field>
-      <field name="mPanelContainer" readonly="true">
-        document.getAnonymousElementByAttribute(this, "anonid", "panelcontainer");
-      </field>
-      <field name="mStringBundle">
-        document.getAnonymousElementByAttribute(this, "anonid", "tbstringbundle");
-      </field>
-      <field name="mCurrentTab">
-        null
-      </field>
-      <field name="_lastRelatedTab">
-        null
-      </field>
-      <field name="mCurrentBrowser">
-        null
-      </field>
-      <field name="mProgressListeners">
-        []
-      </field>
-      <field name="mTabsProgressListeners">
-        []
-      </field>
-      <field name="mTabListeners">
-        []
-      </field>
-      <field name="mTabFilters">
-        []
-      </field>
-      <field name="mIsBusy">
-        false
-      </field>
-      <field name="_outerWindowIDBrowserMap">
-        new Map();
-      </field>
-      <field name="arrowKeysShouldWrap" readonly="true">
-#ifdef XP_MACOSX
-        true
-#else
-        false
-#endif
-      </field>
-
-      <field name="_autoScrollPopup">
-        null
-      </field>
-
-      <field name="_previewMode">
-        false
-      </field>
-
-      <property name="_numPinnedTabs" readonly="true">
-        <getter><![CDATA[
-          for (var i = 0; i < this.tabs.length; i++) {
-            if (!this.tabs[i].pinned)
-              break;
-          }
-          return i;
-        ]]></getter>
-      </property>
-
-      <property name="popupAnchor" readonly="true">
-        <getter><![CDATA[
-        if (this.mCurrentTab._popupAnchor) {
-          return this.mCurrentTab._popupAnchor;
-        }
-        let stack = this.mCurrentBrowser.parentNode;
-        // Create an anchor for the popup
-        const NS_XUL = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
-        let popupAnchor = document.createElementNS(NS_XUL, "hbox");
-        popupAnchor.className = "popup-anchor";
-        popupAnchor.hidden = true;
-        stack.appendChild(popupAnchor);
-        return this.mCurrentTab._popupAnchor = popupAnchor;
-        ]]></getter>
-      </property>
-
-      <method name="updateWindowResizers">
-        <body><![CDATA[
-          if (!window.gShowPageResizers)
-            return;
-
-          var show = document.getElementById("addon-bar").collapsed &&
-                     window.windowState == window.STATE_NORMAL;
-          for (let i = 0; i < this.browsers.length; i++) {
-            this.browsers[i].showWindowResizer = show;
-          }
-        ]]></body>
-      </method>
-
-      <method name="_setCloseKeyState">
-        <parameter name="aEnabled"/>
-        <body><![CDATA[
-          let keyClose = document.getElementById("key_close");
-          let closeKeyEnabled = keyClose.getAttribute("disabled") != "true";
-          if (closeKeyEnabled == aEnabled)
-            return;
-
-          if (aEnabled)
-            keyClose.removeAttribute("disabled");
-          else
-            keyClose.setAttribute("disabled", "true");
-
-          // We also want to remove the keyboard shortcut from the file menu
-          // when the shortcut is disabled, and bring it back when it's
-          // renabled.
-          //
-          // Fixing bug 630826 could make that happen automatically.
-          // Fixing bug 630830 could avoid the ugly hack below.
-
-          let closeMenuItem = document.getElementById("menu_close");
-          let parentPopup = closeMenuItem.parentNode;
-          let nextItem = closeMenuItem.nextSibling;
-          let clonedItem = closeMenuItem.cloneNode(true);
-
-          parentPopup.removeChild(closeMenuItem);
-
-          if (aEnabled)
-            clonedItem.setAttribute("key", "key_close");
-          else
-            clonedItem.removeAttribute("key");
-
-          parentPopup.insertBefore(clonedItem, nextItem);
-        ]]></body>
-      </method>
-
-      <method name="pinTab">
-        <parameter name="aTab"/>
-        <body><![CDATA[
-          if (aTab.pinned)
-            return;
-
-          if (aTab.hidden)
-            this.showTab(aTab);
-
-          this.moveTabTo(aTab, this._numPinnedTabs);
-          aTab.setAttribute("pinned", "true");
-          this.tabContainer._unlockTabSizing();
-          this.tabContainer._positionPinnedTabs();
-          this.tabContainer.adjustTabstrip();
-
-          this.getBrowserForTab(aTab).docShell.isAppTab = true;
-
-          if (aTab.selected)
-            this._setCloseKeyState(false);
-
-          let event = document.createEvent("Events");
-          event.initEvent("TabPinned", true, false);
-          aTab.dispatchEvent(event);
-        ]]></body>
-      </method>
-
-      <method name="unpinTab">
-        <parameter name="aTab"/>
-        <body><![CDATA[
-          if (!aTab.pinned)
-            return;
-
-          this.moveTabTo(aTab, this._numPinnedTabs - 1);
-          aTab.setAttribute("fadein", "true");
-          aTab.removeAttribute("pinned");
-          aTab.style.MozMarginStart = "";
-          this.tabContainer._unlockTabSizing();
-          this.tabContainer._positionPinnedTabs();
-          this.tabContainer.adjustTabstrip();
-
-          this.getBrowserForTab(aTab).docShell.isAppTab = false;
-
-          if (aTab.selected)
-            this._setCloseKeyState(true);
-
-          let event = document.createEvent("Events");
-          event.initEvent("TabUnpinned", true, false);
-          aTab.dispatchEvent(event);
-        ]]></body>
-      </method>
-
-      <method name="previewTab">
-        <parameter name="aTab"/>
-        <parameter name="aCallback"/>
-        <body>
-          <![CDATA[
-            let currentTab = this.selectedTab;
-            try {
-              // Suppress focus, ownership and selected tab changes
-              this._previewMode = true;
-              this.selectedTab = aTab;
-              aCallback();
-            } finally {
-              this.selectedTab = currentTab;
-              this._previewMode = false;
-            }
-          ]]>
-        </body>
-      </method>
-
-      <method name="getBrowserAtIndex">
-        <parameter name="aIndex"/>
-        <body>
-          <![CDATA[
-            return this.browsers[aIndex];
-          ]]>
-        </body>
-      </method>
-
-      <method name="getBrowserIndexForDocument">
-        <parameter name="aDocument"/>
-        <body>
-          <![CDATA[
-            var tab = this._getTabForContentWindow(aDocument.defaultView);
-            return tab ? tab._tPos : -1;
-          ]]>
-        </body>
-      </method>
-
-      <method name="getBrowserForDocument">
-        <parameter name="aDocument"/>
-        <body>
-          <![CDATA[
-            var tab = this._getTabForContentWindow(aDocument.defaultView);
-            return tab ? tab.linkedBrowser : null;
-          ]]>
-        </body>
-      </method>
-
-      <method name="getBrowserForContentWindow">
-        <parameter name="aWindow"/>
-        <body>
-          <![CDATA[
-            var tab = this._getTabForContentWindow(aWindow);
-            return tab ? tab.linkedBrowser : null;
-          ]]>
-        </body>
-      </method>
-
-      <method name="getBrowserForOuterWindowID">
-        <parameter name="aID"/>
-        <body>
-          <![CDATA[
-            return this._outerWindowIDBrowserMap.get(aID);
-          ]]>
-        </body>
-      </method>
-
-      <method name="_getTabForContentWindow">
-        <parameter name="aWindow"/>
-        <body>
-        <![CDATA[
-          for (let i = 0; i < this.browsers.length; i++) {
-            if (this.browsers[i].contentWindow == aWindow)
-              return this.tabs[i];
-          }
-          return null;
-        ]]>
-        </body>
-      </method>
-
-      <!-- Binding from browser to tab -->
-      <field name="_tabForBrowser" readonly="true">
-      <![CDATA[
-        new WeakMap();
-      ]]>
-      </field>
-
-      <method name="_getTabForBrowser">
-        <parameter name="aBrowser" />
-        <body>
-        <![CDATA[
-          let Deprecated = Components.utils.import("resource://gre/modules/Deprecated.jsm", {}).Deprecated;
-          let text = "_getTabForBrowser` is now deprecated, please use `getTabForBrowser";
-          let url = "https://developer.mozilla.org/docs/Mozilla/Tech/XUL/Method/getTabForBrowser";
-          Deprecated.warning(text, url);
-          return this.getTabForBrowser(aBrowser);
-        ]]>
-        </body>
-      </method>
-
-      <method name="getTabForBrowser">
-        <parameter name="aBrowser"/>
-        <body>
-        <![CDATA[
-          return this._tabForBrowser.get(aBrowser);
-        ]]>
-        </body>
-      </method>
-
-      <method name="getNotificationBox">
-        <parameter name="aBrowser"/>
-        <body>
-          <![CDATA[
-            return this.getSidebarContainer(aBrowser).parentNode;
-          ]]>
-        </body>
-      </method>
-
-      <method name="getSidebarContainer">
-        <parameter name="aBrowser"/>
-        <body>
-          <![CDATA[
-            return this.getBrowserContainer(aBrowser).parentNode;
-          ]]>
-        </body>
-      </method>
-
-      <method name="getBrowserContainer">
-        <parameter name="aBrowser"/>
-        <body>
-          <![CDATA[
-            return (aBrowser || this.mCurrentBrowser).parentNode.parentNode;
-          ]]>
-        </body>
-      </method>
-
-      <method name="getTabModalPromptBox">
-        <parameter name="aBrowser"/>
-        <body>
-          <![CDATA[
-            const XUL_NS = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
-            let browser = (aBrowser || this.mCurrentBrowser);
-            let stack = browser.parentNode;
-            let self = this;
-
-            let promptBox = {
-              appendPrompt : function(args, onCloseCallback) {
-                let newPrompt = document.createElementNS(XUL_NS, "tabmodalprompt");
-                // stack.appendChild(newPrompt);
-                stack.insertBefore(newPrompt, browser.nextSibling);
-                browser.setAttribute("tabmodalPromptShowing", true);
-
-                newPrompt.clientTop; // style flush to assure binding is attached
-
-                let prompts = this.listPrompts();
-                if (prompts.length > 1) {
-                  // Let's hide ourself behind the current prompt.
-                  newPrompt.hidden = true;
-                }
-
-                let tab = self._getTabForContentWindow(browser.contentWindow);
-                newPrompt.init(args, tab, onCloseCallback);
-                return newPrompt;
-              },
-
-              removePrompt : function(aPrompt) {
-                stack.removeChild(aPrompt);
-
-                let prompts = this.listPrompts();
-                if (prompts.length) {
-                  let prompt = prompts[prompts.length - 1];
-                  prompt.hidden = false;
-                  prompt.Dialog.setDefaultFocus();
-                } else {
-                  browser.removeAttribute("tabmodalPromptShowing");
-                  browser.focus();
-                }
-              },
-
-              listPrompts : function(aPrompt) {
-                let els = stack.getElementsByTagNameNS(XUL_NS, "tabmodalprompt");
-                // NodeList --> real JS array
-                let prompts = Array.slice(els);
-                return prompts;
-              },
-            };
-
-            return promptBox;
-          ]]>
-        </body>
-      </method>
-
-      <method name="getTabFromAudioEvent">
-        <parameter name="aEvent"/>
-        <body>
-        <![CDATA[
-          if (!Services.prefs.getBoolPref("browser.tabs.showAudioPlayingIcon") ||
-              !aEvent.isTrusted) {
-            return null;
-          }
-
-          var browser = aEvent.originalTarget;
-          var tab = this.getTabForBrowser(browser);
-          return tab;
-        ]]>
-        </body>
-      </method>
-
-      <method name="_callProgressListeners">
-        <parameter name="aBrowser"/>
-        <parameter name="aMethod"/>
-        <parameter name="aArguments"/>
-        <parameter name="aCallGlobalListeners"/>
-        <parameter name="aCallTabsListeners"/>
-        <body><![CDATA[
-          var rv = true;
-
-          if (!aBrowser)
-            aBrowser = this.mCurrentBrowser;
-
-          if (aCallGlobalListeners != false &&
-              aBrowser == this.mCurrentBrowser) {
-            this.mProgressListeners.forEach(function (p) {
-              if (aMethod in p) {
-                try {
-                  if (!p[aMethod].apply(p, aArguments))
-                    rv = false;
-                } catch (e) {
-                  // don't inhibit other listeners
-                  Components.utils.reportError(e);
-                }
-              }
-            });
-          }
-
-          if (aCallTabsListeners != false) {
-            aArguments.unshift(aBrowser);
-
-            this.mTabsProgressListeners.forEach(function (p) {
-              if (aMethod in p) {
-                try {
-                  if (!p[aMethod].apply(p, aArguments))
-                    rv = false;
-                } catch (e) {
-                  // don't inhibit other listeners
-                  Components.utils.reportError(e);
-                }
-              }
-            });
-          }
-
-          return rv;
-        ]]></body>
-      </method>
-
-      <!-- A web progress listener object definition for a given tab. -->
-      <method name="mTabProgressListener">
-        <parameter name="aTab"/>
-        <parameter name="aBrowser"/>
-        <parameter name="aStartsBlank"/>
-        <body>
-        <![CDATA[
-          return ({
-            mTabBrowser: this,
-            mTab: aTab,
-            mBrowser: aBrowser,
-            mBlank: aStartsBlank,
-
-            // cache flags for correct status UI update after tab switching
-            mStateFlags: 0,
-            mStatus: 0,
-            mMessage: "",
-            mTotalProgress: 0,
-
-            // count of open requests (should always be 0 or 1)
-            mRequestCount: 0,
-
-            destroy: function () {
-              delete this.mTab;
-              delete this.mBrowser;
-              delete this.mTabBrowser;
-            },
-
-            _callProgressListeners: function () {
-              Array.unshift(arguments, this.mBrowser);
-              return this.mTabBrowser._callProgressListeners.apply(this.mTabBrowser, arguments);
-            },
-
-            _shouldShowProgress: function (aRequest) {
-              if (this.mBlank)
-                return false;
-
-              if (gMultiProcessBrowser)
-                return true;
-
-              // Don't show progress indicators in tabs for about: URIs
-              // pointing to local resources.
-              try {
-                let channel = aRequest.QueryInterface(Ci.nsIChannel);
-                if (channel.originalURI.schemeIs("about") &&
-                    (channel.URI.schemeIs("jar") || channel.URI.schemeIs("file")))
-                  return false;
-              } catch (e) {}
-
-              return true;
-            },
-
-            onProgressChange: function (aWebProgress, aRequest,
-                                        aCurSelfProgress, aMaxSelfProgress,
-                                        aCurTotalProgress, aMaxTotalProgress) {
-              this.mTotalProgress = aMaxTotalProgress ? aCurTotalProgress / aMaxTotalProgress : 0;
-
-              if (!this._shouldShowProgress(aRequest))
-                return;
-
-              if (this.mTotalProgress)
-                this.mTab.setAttribute("progress", "true");
-
-              this._callProgressListeners("onProgressChange",
-                                          [aWebProgress, aRequest,
-                                           aCurSelfProgress, aMaxSelfProgress,
-                                           aCurTotalProgress, aMaxTotalProgress]);
-            },
-
-            onProgressChange64: function (aWebProgress, aRequest,
-                                          aCurSelfProgress, aMaxSelfProgress,
-                                          aCurTotalProgress, aMaxTotalProgress) {
-              return this.onProgressChange(aWebProgress, aRequest,
-                aCurSelfProgress, aMaxSelfProgress, aCurTotalProgress,
-                aMaxTotalProgress);
-            },
-
-            onStateChange: function (aWebProgress, aRequest, aStateFlags, aStatus) {
-              if (!aRequest)
-                return;
-
-              var oldBlank = this.mBlank;
-
-              const nsIWebProgressListener = Components.interfaces.nsIWebProgressListener;
-              const nsIChannel = Components.interfaces.nsIChannel;
-              let location, originalLocation;
-              try {
-                aRequest.QueryInterface(nsIChannel)
-                location = aRequest.URI;
-                originalLocation = aRequest.originalURI;
-              } catch (ex) {}
-
-              if (aStateFlags & nsIWebProgressListener.STATE_START) {
-                this.mRequestCount++;
-              }
-              else if (aStateFlags & nsIWebProgressListener.STATE_STOP) {
-                const NS_ERROR_UNKNOWN_HOST = 2152398878;
-                if (--this.mRequestCount > 0 && aStatus == NS_ERROR_UNKNOWN_HOST) {
-                  // to prevent bug 235825: wait for the request handled
-                  // by the automatic keyword resolver
-                  return;
-                }
-                // since we (try to) only handle STATE_STOP of the last request,
-                // the count of open requests should now be 0
-                this.mRequestCount = 0;
-              }
-
-              if (aStateFlags & nsIWebProgressListener.STATE_START &&
-                  aStateFlags & nsIWebProgressListener.STATE_IS_NETWORK) {
-                if (aWebProgress.isTopLevel)
-                  this.mBrowser.urlbarChangeTracker.startedLoad();
-
-                if (this._shouldShowProgress(aRequest)) {
-                  if (!(aStateFlags & nsIWebProgressListener.STATE_RESTORING)) {
-                    this.mTab.setAttribute("busy", "true");
-                    if (!gMultiProcessBrowser) {
-                      if (aWebProgress.isTopLevel &&
-                          !(this.mBrowser.docShell.loadType & Ci.nsIDocShell.LOAD_CMD_RELOAD))
-                        this.mTabBrowser.setTabTitleLoading(this.mTab);
-                    }
-                  }
-
-                  if (this.mTab.selected)
-                    this.mTabBrowser.mIsBusy = true;
-                }
-              }
-              else if (aStateFlags & nsIWebProgressListener.STATE_STOP &&
-                       aStateFlags & nsIWebProgressListener.STATE_IS_NETWORK) {
-
-                if (this.mTab.hasAttribute("busy")) {
-                  this.mTab.removeAttribute("busy");
-                  this.mTabBrowser._tabAttrModified(this.mTab, ["busy"]);
-                  if (!this.mTab.selected)
-                    this.mTab.setAttribute("unread", "true");
-                }
-                this.mTab.removeAttribute("progress");
-
-                if (aWebProgress.isTopLevel) {
-                  let isSuccessful = Components.isSuccessCode(aStatus);
-                  if (!isSuccessful && !isTabEmpty(this.mTab)) {
-                    // Restore the current document's location in case the
-                    // request was stopped (possibly from a content script)
-                    // before the location changed.
-
-                    this.mBrowser.userTypedValue = null;
-
-                    if (this.mTab.selected && gURLBar)
-                      URLBarSetURI();
-                  } else if (isSuccessful) {
-                    this.mBrowser.urlbarChangeTracker.finishedLoad();
-                  }
-
-                  if (!this.mBrowser.mIconURL)
-                    this.mTabBrowser.useDefaultIcon(this.mTab);
-                }
-
-                if (this.mBlank)
-                  this.mBlank = false;
-
-                // For keyword URIs clear the user typed value since they will be changed into real URIs
-                if (location.scheme == "keyword")
-                  this.mBrowser.userTypedValue = null;
-
-                if (this.mTab.label == this.mTabBrowser.mStringBundle.getString("tabs.connecting"))
-                  this.mTabBrowser.setTabTitle(this.mTab);
-
-                if (this.mTab.selected)
-                  this.mTabBrowser.mIsBusy = false;
-              }
-
-              if (oldBlank) {
-                this._callProgressListeners("onUpdateCurrentBrowser",
-                                            [aStateFlags, aStatus, "", 0],
-                                            true, false);
-              } else {
-                this._callProgressListeners("onStateChange",
-                                            [aWebProgress, aRequest, aStateFlags, aStatus],
-                                            true, false);
-              }
-
-              this._callProgressListeners("onStateChange",
-                                          [aWebProgress, aRequest, aStateFlags, aStatus],
-                                          false);
-
-              if (aStateFlags & (nsIWebProgressListener.STATE_START |
-                                 nsIWebProgressListener.STATE_STOP)) {
-                // reset cached temporary values at beginning and end
-                this.mMessage = "";
-                this.mTotalProgress = 0;
-              }
-              this.mStateFlags = aStateFlags;
-              this.mStatus = aStatus;
-            },
-
-            onLocationChange: function (aWebProgress, aRequest, aLocation,
-                                        aFlags) {
-              // OnLocationChange is called for both the top-level content
-              // and the subframes.
-              let topLevel = aWebProgress.isTopLevel;
-
-              if (topLevel) {
-                let isSameDocument =
-                  !!(aFlags & Ci.nsIWebProgressListener.LOCATION_CHANGE_SAME_DOCUMENT);
-                // We need to clear the typed value
-                // if the document failed to load, to make sure the urlbar reflects the
-                // failed URI (particularly for SSL errors). However, don't clear the value
-                // if the error page's URI is about:blank, because that causes complete
-                // loss of urlbar contents for invalid URI errors (see bug 867957).
-                if (this.mBrowser.didStartLoadSinceLastUserTyping() ||
-                    ((aFlags & Ci.nsIWebProgressListener.LOCATION_CHANGE_ERROR_PAGE) &&
-                     aLocation.spec != "about:blank"))
-                  this.mBrowser.userTypedValue = null;
-
-                // If the browser was playing audio, we should remove the playing state.
-                if (this.mTab.hasAttribute("soundplaying") && !isSameDocument) {
-                  clearTimeout(this.mTab._soundPlayingAttrRemovalTimer);
-                  this.mTab._soundPlayingAttrRemovalTimer = 0;
-                  this.mTab.removeAttribute("soundplaying");
-                  this.mTabBrowser._tabAttrModified(this.mTab, ["soundplaying"]);
-                }
-
-                // If the browser was previously muted, we should restore the muted state.
-                if (this.mTab.hasAttribute("muted")) {
-                  this.mTab.linkedBrowser.mute();
-                }
-
-                // Don't clear the favicon if this onLocationChange was
-                // triggered by a pushState or a replaceState.  See bug 550565.
-                if (!gMultiProcessBrowser) {
-                  if (aWebProgress.isLoadingDocument &&
-                      !(this.mBrowser.docShell.loadType & Ci.nsIDocShell.LOAD_CMD_PUSHSTATE))
-                    this.mBrowser.mIconURL = null;
-                }
-
-                let autocomplete = this.mTabBrowser._placesAutocomplete;
-                if (this.mBrowser.registeredOpenURI) {
-                  autocomplete.unregisterOpenPage(this.mBrowser.registeredOpenURI);
-                  delete this.mBrowser.registeredOpenURI;
-                }
-                // Tabs in private windows aren't registered as "Open" so
-                // that they don't appear as switch-to-tab candidates.
-                if (!isBlankPageURL(aLocation.spec) &&
-                    (!PrivateBrowsingUtils.isWindowPrivate(window) ||
-                    PrivateBrowsingUtils.permanentPrivateBrowsing)) {
-                  autocomplete.registerOpenPage(aLocation);
-                  this.mBrowser.registeredOpenURI = aLocation;
-                }
-              }
-
-              if (!this.mBlank) {
-                this._callProgressListeners("onLocationChange",
-                                            [aWebProgress, aRequest, aLocation,
-                                             aFlags]);
-              }
-
-              if (topLevel) {
-                this.mBrowser.lastURI = aLocation;
-                this.mBrowser.lastLocationChange = Date.now();
-              }
-            },
-
-            onStatusChange: function (aWebProgress, aRequest, aStatus, aMessage) {
-              if (this.mBlank)
-                return;
-
-              this._callProgressListeners("onStatusChange",
-                                          [aWebProgress, aRequest, aStatus, aMessage]);
-
-              this.mMessage = aMessage;
-            },
-
-            onSecurityChange: function (aWebProgress, aRequest, aState) {
-              this._callProgressListeners("onSecurityChange",
-                                          [aWebProgress, aRequest, aState]);
-            },
-
-            onRefreshAttempted: function (aWebProgress, aURI, aDelay, aSameURI) {
-              return this._callProgressListeners("onRefreshAttempted",
-                                                 [aWebProgress, aURI, aDelay, aSameURI]);
-            },
-
-            QueryInterface: function (aIID) {
-              if (aIID.equals(Components.interfaces.nsIWebProgressListener) ||
-                  aIID.equals(Components.interfaces.nsIWebProgressListener2) ||
-                  aIID.equals(Components.interfaces.nsISupportsWeakReference) ||
-                  aIID.equals(Components.interfaces.nsISupports))
-                return this;
-              throw Components.results.NS_NOINTERFACE;
-            }
-          });
-        ]]>
-        </body>
-      </method>
-
-      <method name="setIcon">
-        <parameter name="aTab"/>
-        <parameter name="aURI"/>
-        <parameter name="aLoadingPrincipal"/>
-        <body>
-          <![CDATA[
-            let browser = this.getBrowserForTab(aTab);
-            browser.mIconURL = aURI instanceof Ci.nsIURI ? aURI.spec : aURI;
-
-            if (aURI && this.mFaviconService) {
-              if (!(aURI instanceof Ci.nsIURI)) {
-                aURI = makeURI(aURI);
-              }
-              // We do not serialize the principal from within SessionStore.jsm,
-              // hence if aLoadingPrincipal is null we default to the
-              // systemPrincipal which will allow the favicon to load.
-              let loadingPrincipal = aLoadingPrincipal
-                ? aLoadingPrincipal
-                : Services.scriptSecurityManager.getSystemPrincipal();
-              let loadType = PrivateBrowsingUtils.isWindowPrivate(window)
-                ? this.mFaviconService.FAVICON_LOAD_PRIVATE
-                : this.mFaviconService.FAVICON_LOAD_NON_PRIVATE;
-
-              this.mFaviconService.setAndFetchFaviconForPage(
-                browser.currentURI, aURI, false, loadType, null, loadingPrincipal);
-            }
-
-            let sizedIconUrl = browser.mIconURL || "";
-            if (sizedIconUrl != aTab.getAttribute("image")) {
-              if (sizedIconUrl)
-                aTab.setAttribute("image", sizedIconUrl);
-              else
-                aTab.removeAttribute("image");
-              this._tabAttrModified(aTab, ["image"]);
-            }
-
-            if (Services.prefs.getBoolPref("browser.chrome.favicons.process")) {
-              let favImage = new Image;
-              favImage.src = browser.mIconURL;
-              var tabBrowser = this;
-              favImage.onload = function () {
-                try {
-                  // Draw the icon on a hidden canvas
-                  var canvas = document.createElementNS("http://www.w3.org/1999/xhtml", "canvas");
-                  var tabImg = document.getAnonymousElementByAttribute(aTab, "anonid", "tab-icon");
-                  var w = tabImg.boxObject.width;
-                  var h = tabImg.boxObject.height;
-                  canvas.width = w;
-                  canvas.height = h;
-                  var ctx = canvas.getContext('2d');
-                  ctx.drawImage(favImage, 0, 0, w, h);
-                  icon = canvas.toDataURL();
-                  browser.mIconURL = icon;
-                  aTab.setAttribute("image", icon);
-                }
-                catch (e) {
-                  console.warn("Processing of favicon failed.");
-                  // Canvas failed: icon remains as it was
-                }
-                tabBrowser._callProgressListeners(browser, "onLinkIconAvailable", [browser.mIconURL]);
-              }
-            }
-                
-            this._callProgressListeners(browser, "onLinkIconAvailable", [browser.mIconURL]);
-          ]]>
-        </body>
-      </method>
-
-      <method name="getIcon">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            let browser = aTab ? this.getBrowserForTab(aTab) : this.selectedBrowser;
-            return browser.mIconURL;
-          ]]>
-        </body>
-      </method>
-
-      <method name="shouldLoadFavIcon">
-        <parameter name="aURI"/>
-        <body>
-          <![CDATA[
-            return (aURI &&
-                    Services.prefs.getBoolPref("browser.chrome.site_icons") &&
-                    Services.prefs.getBoolPref("browser.chrome.favicons") &&
-                    ("schemeIs" in aURI) && (aURI.schemeIs("http") || aURI.schemeIs("https")));
-          ]]>
-        </body>
-      </method>
-
-      <method name="useDefaultIcon">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            // Bug 691610 - e10s support for useDefaultIcon
-            if (gMultiProcessBrowser)
-              return;
-
-            var browser = this.getBrowserForTab(aTab);
-            var docURIObject = browser.contentDocument.documentURIObject;
-            var icon = null;
-            <!-- Pale Moon: new image icon method, see bug #305986 -->
-            let req = browser.contentDocument.imageRequest;
-            let sz = Services.prefs.getIntPref("browser.chrome.image_icons.max_size");
-            if (browser.contentDocument instanceof ImageDocument && 
-                req && req.image) {
-              if (Services.prefs.getBoolPref("browser.chrome.site_icons") && sz) {
-                try {
-                  <!-- Main method: draw on a hidden canvas -->
-                  var canvas = document.createElementNS("http://www.w3.org/1999/xhtml", "canvas");
-                  var tabImg = document.getAnonymousElementByAttribute(aTab, "anonid", "tab-icon");
-                  var w = tabImg.boxObject.width;
-                  var h = tabImg.boxObject.height;
-                  canvas.width = w;
-                  canvas.height = h;
-                  var ctx = canvas.getContext('2d');
-                  ctx.drawImage(browser.contentDocument.body.firstChild, 0, 0, w, h);
-                  icon = canvas.toDataURL();
-                }
-                catch (e) { 
-                  <!-- Fallback method in case canvas method fails, restricted by sz -->
-                  try {
-                  
-                    if (req &&
-                        req.image &&
-                        req.image.width <= sz &&
-                        req.image.height <= sz)
-                      icon = browser.currentURI;
-                  } 
-                  catch (e) { 
-                    <!-- Both methods fail (very large or corrupt image): icon remains null -->
-                  }
-                }
-              }
-            }
-            // Use documentURIObject in the check for shouldLoadFavIcon so that we
-            // do the right thing with about:-style error pages.  Bug 453442
-            else if (this.shouldLoadFavIcon(docURIObject)) {
-              let url = docURIObject.prePath + "/favicon.ico";
-              if (!this.isFailedIcon(url))
-                icon = url;
-            }
-            this.setIcon(aTab, icon, browser.contentPrincipal);
-          ]]>
-        </body>
-      </method>
-
-      <method name="isFailedIcon">
-        <parameter name="aURI"/>
-        <body>
-          <![CDATA[
-            if (this.mFaviconService) {
-              if (!(aURI instanceof Ci.nsIURI))
-                aURI = makeURI(aURI);
-              return this.mFaviconService.isFailedFavicon(aURI);
-            }
-            return null;
-          ]]>
-        </body>
-      </method>
-
-      <method name="getWindowTitleForBrowser">
-        <parameter name="aBrowser"/>
-        <body>
-          <![CDATA[
-            var newTitle = "";
-            var docElement = this.ownerDocument.documentElement;
-            var sep = docElement.getAttribute("titlemenuseparator");
-
-            // Strip out any null bytes in the content title, since the
-            // underlying widget implementations of nsWindow::SetTitle pass
-            // null-terminated strings to system APIs.
-            var docTitle = aBrowser.contentTitle.replace("\0", "", "g");
-
-            if (!docTitle)
-              docTitle = docElement.getAttribute("titledefault");
-
-            var modifier = docElement.getAttribute("titlemodifier");
-            if (docTitle) {
-              newTitle += docElement.getAttribute("titlepreface");
-              newTitle += docTitle;
-              if (modifier)
-                newTitle += sep;
-            }
-            newTitle += modifier;
-
-            // If location bar is hidden and the URL type supports a host,
-            // add the scheme and host to the title to prevent spoofing.
-            // XXX https://bugzilla.mozilla.org/show_bug.cgi?id=22183#c239
-            try {
-              if (docElement.getAttribute("chromehidden").includes("location")) {
-                var uri = this.mURIFixup.createExposableURI(
-                            aBrowser.currentURI);
-                if (uri.scheme == "about")
-                  newTitle = uri.spec + sep + newTitle;
-                else
-                  newTitle = uri.prePath + sep + newTitle;
-              }
-            } catch (e) {}
-
-            return newTitle;
-          ]]>
-        </body>
-      </method>
-
-      <method name="freezeTitlebar">
-        <parameter name="aTitle"/>
-        <body>
-          <![CDATA[
-            this._frozenTitle = aTitle || "";
-            this.updateTitlebar();
-          ]]>
-        </body>
-      </method>
-
-      <method name="unfreezeTitlebar">
-        <body>
-          <![CDATA[
-            this._frozenTitle = "";
-            this.updateTitlebar();
-          ]]>
-        </body>
-      </method>
-
-      <method name="updateTitlebar">
-        <body>
-          <![CDATA[
-            this.ownerDocument.title = this._frozenTitle ||
-              this.getWindowTitleForBrowser(this.mCurrentBrowser);
-          ]]>
-        </body>
-      </method>
-
-      <method name="updateCurrentBrowser">
-        <parameter name="aForceUpdate"/>
-        <body>
-          <![CDATA[
-            var newBrowser = this.getBrowserAtIndex(this.tabContainer.selectedIndex);
-            if (this.mCurrentBrowser == newBrowser && !aForceUpdate)
-              return;
-
-            if (!aForceUpdate) {
-              window.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils)
-                                                             .beginTabSwitch();
-            }
-
-            var oldTab = this.mCurrentTab;
-
-            // Preview mode should not reset the owner
-            if (!this._previewMode && !oldTab.selected)
-              oldTab.owner = null;
-
-            if (this._lastRelatedTab) {
-              if (!this._lastRelatedTab.selected)
-                this._lastRelatedTab.owner = null;
-              this._lastRelatedTab = null;
-            }
-
-            var oldBrowser = this.mCurrentBrowser;
-            if (oldBrowser) {
-              oldBrowser.setAttribute("type", "content-targetable");
-              oldBrowser.docShellIsActive = false;
-              this.finder.mListeners.forEach(l => oldBrowser.finder.removeResultListener(l));
-            }
-
-            var updateBlockedPopups = false;
-            if (!oldBrowser ||
-                (oldBrowser.blockedPopups && !newBrowser.blockedPopups) ||
-                (!oldBrowser.blockedPopups && newBrowser.blockedPopups))
-              updateBlockedPopups = true;
-
-            newBrowser.setAttribute("type", "content-primary");
-            newBrowser.docShellIsActive =
-              (window.windowState != window.STATE_MINIMIZED);
-            this.mCurrentBrowser = newBrowser;
-            this.mCurrentTab = this.tabContainer.selectedItem;
-            this.finder.mListeners.forEach(l => this.mCurrentBrowser.finder.addResultListener(l));
-            this.showTab(this.mCurrentTab);
-
-            var backForwardContainer = document.getElementById("unified-back-forward-button");
-            if (backForwardContainer) {
-              backForwardContainer.setAttribute("switchingtabs", "true");
-              window.addEventListener("MozAfterPaint", function removeSwitchingtabsAttr() {
-                window.removeEventListener("MozAfterPaint", removeSwitchingtabsAttr);
-                backForwardContainer.removeAttribute("switchingtabs");
-              });
-            }
-
-            if (updateBlockedPopups)
-              this.mCurrentBrowser.updateBlockedPopups();
-
-            // Update the URL bar.
-            var loc = this.mCurrentBrowser.currentURI;
-
-            // Bug 666809 - SecurityUI support for e10s
-            var webProgress = this.mCurrentBrowser.webProgress;
-            var securityUI = this.mCurrentBrowser.securityUI;
-            
-            // Update global findbar with new content browser
-            if (gFindBarInitialized) {
-              gFindBar.browser = newBrowser;
-            }
-
-            this._callProgressListeners(null, "onLocationChange",
-                                        [webProgress, null, loc, 0], true,
-                                        false);
-
-            if (securityUI) {
-              this._callProgressListeners(null, "onSecurityChange",
-                                          [webProgress, null, securityUI.state], true, false);
-            }
-
-            var listener = this.mTabListeners[this.tabContainer.selectedIndex] || null;
-            if (listener && listener.mStateFlags) {
-              this._callProgressListeners(null, "onUpdateCurrentBrowser",
-                                          [listener.mStateFlags, listener.mStatus,
-                                           listener.mMessage, listener.mTotalProgress],
-                                          true, false);
-            }
-
-            if (!this._previewMode) {
-              this.mCurrentTab.removeAttribute("unread");
-              this.selectedTab.lastAccessed = Date.now();
-
-              // Bug 666816 - TypeAheadFind support for e10s
-              if (!gMultiProcessBrowser)
-                this._fastFind.setDocShell(this.mCurrentBrowser.docShell);
-
-              this.updateTitlebar();
-
-              this.mCurrentTab.removeAttribute("titlechanged");
-            }
-
-            // If the new tab is busy, and our current state is not busy, then
-            // we need to fire a start to all progress listeners.
-            const nsIWebProgressListener = Components.interfaces.nsIWebProgressListener;
-            if (this.mCurrentTab.hasAttribute("busy") && !this.mIsBusy) {
-              this.mIsBusy = true;
-              this._callProgressListeners(null, "onStateChange",
-                                          [webProgress, null,
-                                           nsIWebProgressListener.STATE_START |
-                                           nsIWebProgressListener.STATE_IS_NETWORK, 0],
-                                          true, false);
-            }
-
-            // If the new tab is not busy, and our current state is busy, then
-            // we need to fire a stop to all progress listeners.
-            if (!this.mCurrentTab.hasAttribute("busy") && this.mIsBusy) {
-              this.mIsBusy = false;
-              this._callProgressListeners(null, "onStateChange",
-                                          [webProgress, null,
-                                           nsIWebProgressListener.STATE_STOP |
-                                           nsIWebProgressListener.STATE_IS_NETWORK, 0],
-                                          true, false);
-            }
-
-            this._setCloseKeyState(!this.mCurrentTab.pinned);
-
-            // TabSelect events are suppressed during preview mode to avoid confusing extensions and other bits of code
-            // that might rely upon the other changes suppressed.
-            // Focus is suppressed in the event that the main browser window is minimized - focusing a tab would restore the window
-            if (!this._previewMode) {
-              // We've selected the new tab, so go ahead and notify listeners.
-              let event = new CustomEvent("TabSelect", {
-                bubbles: true,
-                cancelable: false,
-                detail: {
-                  previousTab: oldTab
-                }
-              });
-              this.mCurrentTab.dispatchEvent(event);
-
-              this._tabAttrModified(oldTab, ["selected"]);
-              this._tabAttrModified(this.mCurrentTab, ["selected"]);
-
-              // Adjust focus
-              oldBrowser._urlbarFocused = (gURLBar && gURLBar.focused);
-              do {
-                // When focus is in the tab bar, retain it there.
-                if (document.activeElement == oldTab) {
-                  // We need to explicitly focus the new tab, because
-                  // tabbox.xml does this only in some cases.
-                  this.mCurrentTab.focus();
-                  break;
-                }
-
-                // If there's a tabmodal prompt showing, focus it.
-                if (newBrowser.hasAttribute("tabmodalPromptShowing")) {
-                  let XUL_NS = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
-                  let prompts = newBrowser.parentNode.getElementsByTagNameNS(XUL_NS, "tabmodalprompt");
-                  let prompt = prompts[prompts.length - 1];
-                  prompt.Dialog.setDefaultFocus();
-                  break;
-                }
-
-                // Focus the location bar if it was previously focused for that tab.
-                // In full screen mode, only bother making the location bar visible
-                // if the tab is a blank one.
-                if (newBrowser._urlbarFocused && gURLBar) {
-
-                  // Explicitly close the popup if the URL bar retains focus
-                  gURLBar.closePopup();
-
-                  if (!window.fullScreen) {
-                    gURLBar.focus();
-                    break;
-                  } else if (isTabEmpty(this.mCurrentTab)) {
-                    focusAndSelectUrlBar();
-                    break;
-                  }
-                }
-
-                // If the find bar is focused, keep it focused.
-                if (gFindBarInitialized &&
-                    !gFindBar.hidden &&
-                    gFindBar.getElement("findbar-textbox").getAttribute("focused") == "true")
-                  break;
-
-                // Otherwise, focus the content area.
-                let fm = Cc["@mozilla.org/focus-manager;1"].getService(Ci.nsIFocusManager);
-                let focusFlags = fm.FLAG_NOSCROLL;
-
-                if (!gMultiProcessBrowser) {
-                  let newFocusedElement = fm.getFocusedElementForWindow(window.content, true, {});
-
-                  // for anchors, use FLAG_SHOWRING so that it is clear what link was
-                  // last clicked when switching back to that tab
-                  if (newFocusedElement &&
-                      (newFocusedElement instanceof HTMLAnchorElement ||
-                       newFocusedElement.getAttributeNS("http://www.w3.org/1999/xlink", "type") == "simple"))
-                    focusFlags |= fm.FLAG_SHOWRING;
-                }
-                fm.setFocus(newBrowser, focusFlags);
-              } while (false);
-            }
-
-            this.tabContainer._setPositionalAttributes();
-          ]]>
-        </body>
-      </method>
-
-      <method name="_tabAttrModified">
-        <parameter name="aTab"/>
-        <parameter name="aChanged"/>
-        <body><![CDATA[
-          if (aTab.closing)
-            return;
-
-          let event = new CustomEvent("TabAttrModified", {
-            bubbles: true,
-            cancelable: false,
-            detail: {
-              changed: aChanged,
-            }
-          });
-          aTab.dispatchEvent(event);
-        ]]></body>
-      </method>
-
-      <method name="setTabTitleLoading">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            aTab.label = this.mStringBundle.getString("tabs.connecting");
-            aTab.crop = "end";
-            this._tabAttrModified(aTab, ["label", "crop"]);
-          ]]>
-        </body>
-      </method>
-
-      <method name="setTabTitle">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            var browser = this.getBrowserForTab(aTab);
-            var crop = "end";
-            var title = browser.contentTitle;
-
-            if (!title) {
-              if (browser.currentURI.spec) {
-                try {
-                  title = this.mURIFixup.createExposableURI(browser.currentURI).spec;
-                } catch(ex) {
-                  title = browser.currentURI.spec;
-                }
-              }
-
-              if (title && !isBlankPageURL(title)) {
-                // At this point, we now have a URI.
-                // Let's try to unescape it using a character set
-                // in case the URI is not ASCII.
-                try {
-                  var characterSet = browser.characterSet;
-                  const textToSubURI = Components.classes["@mozilla.org/intl/texttosuburi;1"]
-                                                 .getService(Components.interfaces.nsITextToSubURI);
-                  title = textToSubURI.unEscapeNonAsciiURI(characterSet, title);
-                } catch(ex) { /* Do nothing. */ }
-
-                crop = "center";
-
-              } else // Still no title?  Fall back to our untitled string.
-                title = this.mStringBundle.getString("tabs.emptyTabTitle");
-            }
-
-            if (aTab.label == title &&
-                aTab.crop == crop)
-              return false;
-
-            aTab.label = title;
-            aTab.crop = crop;
-            this._tabAttrModified(aTab, ["label", "crop"]);
-
-            if (aTab.selected)
-              this.updateTitlebar();
-
-            return true;
-          ]]>
-        </body>
-      </method>
-
-      <method name="loadOneTab">
-        <parameter name="aURI"/>
-        <parameter name="aReferrerURI"/>
-        <parameter name="aCharset"/>
-        <parameter name="aPostData"/>
-        <parameter name="aLoadInBackground"/>
-        <parameter name="aAllowThirdPartyFixup"/>
-        <body>
-          <![CDATA[
-            var aTriggeringPrincipal;
-            var aReferrerPolicy;
-            var aFromExternal;
-            var aRelatedToCurrent;
-            var aOriginPrincipal;
-            var aOpener;
-            if (arguments.length == 2 &&
-                typeof arguments[1] == "object" &&
-                !(arguments[1] instanceof Ci.nsIURI)) {
-              let params = arguments[1];
-              aTriggeringPrincipal  = params.triggeringPrincipal;
-              aReferrerURI          = params.referrerURI;
-              aReferrerPolicy       = params.referrerPolicy;
-              aCharset              = params.charset;
-              aPostData             = params.postData;
-              aLoadInBackground     = params.inBackground;
-              aAllowThirdPartyFixup = params.allowThirdPartyFixup;
-              aFromExternal         = params.fromExternal;
-              aRelatedToCurrent     = params.relatedToCurrent;
-              aOriginPrincipal      = params.originPrincipal;
-              aOpener               = params.opener;
-            }
-
-            var bgLoad = (aLoadInBackground != null) ? aLoadInBackground :
-                         Services.prefs.getBoolPref("browser.tabs.loadInBackground");
-            var owner = bgLoad ? null : this.selectedTab;
-            var tab = this.addTab(aURI, {
-                                  triggeringPrincipal: aTriggeringPrincipal,
-                                  referrerURI: aReferrerURI,
-                                  referrerPolicy: aReferrerPolicy,
-                                  charset: aCharset,
-                                  postData: aPostData,
-                                  ownerTab: owner,
-                                  allowThirdPartyFixup: aAllowThirdPartyFixup,
-                                  fromExternal: aFromExternal,
-                                  originPrincipal: aOriginPrincipal,
-                                  relatedToCurrent: aRelatedToCurrent,
-                                  opener: aOpener });
-            if (!bgLoad)
-              this.selectedTab = tab;
-
-            return tab;
-         ]]>
-        </body>
-      </method>
-
-      <method name="loadTabs">
-        <parameter name="aURIs"/>
-        <parameter name="aLoadInBackground"/>
-        <parameter name="aReplace"/>
-        <body><![CDATA[
-          let aAllowThirdPartyFixup;
-          let aTargetTab;
-          let aNewIndex = -1;
-          let aPostDatas = [];
-          if (arguments.length == 2 &&
-              typeof arguments[1] == "object") {
-            let params = arguments[1];
-            aLoadInBackground     = params.inBackground;
-            aReplace              = params.replace;
-            aAllowThirdPartyFixup = params.allowThirdPartyFixup;
-            aTargetTab            = params.targetTab;
-            aNewIndex             = typeof params.newIndex === "number" ?
-                                    params.newIndex : aNewIndex;
-            aPostDatas            = params.postDatas || aPostDatas;
-          }
-
-          if (!aURIs.length)
-            return;
-
-          // The tab selected after this new tab is closed (i.e. the new tab's
-          // "owner") is the next adjacent tab (i.e. not the previously viewed tab)
-          // when several urls are opened here (i.e. closing the first should select
-          // the next of many URLs opened) or if the pref to have UI links opened in
-          // the background is set (i.e. the link is not being opened modally)
-          //
-          // i.e.
-          //    Number of URLs    Load UI Links in BG       Focus Last Viewed?
-          //    == 1              false                     YES
-          //    == 1              true                      NO
-          //    > 1               false/true                NO
-          var multiple = aURIs.length > 1;
-          var owner = multiple || aLoadInBackground ? null : this.selectedTab;
-          var firstTabAdded = null;
-          var targetTabIndex = -1;
-
-          if (aReplace) {
-            let browser;
-            if (aTargetTab) {
-              browser = this.getBrowserForTab(aTargetTab);
-              targetTabIndex = aTargetTab._tPos;
-            } else {
-              browser = this.mCurrentBrowser;
-              targetTabIndex = this.tabContainer.selectedIndex;
-            }
-            let flags = Ci.nsIWebNavigation.LOAD_FLAGS_NONE;
-            if (aAllowThirdPartyFixup) {
-              flags |= Ci.nsIWebNavigation.LOAD_FLAGS_ALLOW_THIRD_PARTY_FIXUP |
-                       Ci.nsIWebNavigation.LOAD_FLAGS_FIXUP_SCHEME_TYPOS;
-            }
-            try {
-              browser.loadURIWithFlags(aURIs[0], {
-                flags, postData: aPostDatas[0]
-              });
-            } catch (e) {
-              // Ignore failure in case a URI is wrong, so we can continue
-              // opening the next ones.
-            }
-          } else {
-            firstTabAdded = this.addTab(aURIs[0], {
-              ownerTab: owner,
-              skipAnimation: multiple,
-              allowThirdPartyFixup: aAllowThirdPartyFixup,
-              postData: aPostDatas[0]
-            });
-            if (aNewIndex !== -1) {
-              this.moveTabTo(firstTabAdded, aNewIndex);
-              targetTabIndex = firstTabAdded._tPos;
-            }
-          }
-
-          let tabNum = targetTabIndex;
-          for (let i = 1; i < aURIs.length; ++i) {
-            let tab = this.addTab(aURIs[i], {
-              skipAnimation: true,
-              allowThirdPartyFixup: aAllowThirdPartyFixup,
-              postData: aPostDatas[i]
-            });
-            if (targetTabIndex !== -1)
-              this.moveTabTo(tab, ++tabNum);
-          }
-
-          if (!aLoadInBackground) {
-            if (firstTabAdded) {
-              // .selectedTab setter focuses the content area
-              this.selectedTab = firstTabAdded;
-            }
-            else
-              this.selectedBrowser.focus();
-          }
-        ]]></body>
-      </method>
-
-      <method name="addTab">
-        <parameter name="aURI"/>
-        <parameter name="aReferrerURI"/>
-        <parameter name="aCharset"/>
-        <parameter name="aPostData"/>
-        <parameter name="aOwner"/>
-        <parameter name="aAllowThirdPartyFixup"/>
-        <body>
-          <![CDATA[
-            const NS_XUL = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
-            var aTriggeringPrincipal;
-            var aReferrerPolicy;
-            var aFromExternal;
-            var aRelatedToCurrent;
-            var aSkipAnimation;
-            var aOriginPrincipal;
-            var aSkipBackgroundNotify;
-            var aOpener;
-            if (arguments.length == 2 &&
-                typeof arguments[1] == "object" &&
-                !(arguments[1] instanceof Ci.nsIURI)) {
-              let params = arguments[1];
-              aTriggeringPrincipal  = params.triggeringPrincipal;
-              aReferrerURI          = params.referrerURI;
-              aReferrerPolicy       = params.referrerPolicy;
-              aCharset              = params.charset;
-              aPostData             = params.postData;
-              aOwner                = params.ownerTab;
-              aAllowThirdPartyFixup = params.allowThirdPartyFixup;
-              aFromExternal         = params.fromExternal;
-              aRelatedToCurrent     = params.relatedToCurrent;
-              aSkipAnimation        = params.skipAnimation;
-              aOriginPrincipal      = params.originPrincipal;
-              aOpener               = params.opener;
-              aSkipBackgroundNotify = params.skipBackgroundNotify;
-            }
-
-            // if we're adding tabs, we're past interrupt mode, ditch the owner
-            if (this.mCurrentTab.owner)
-              this.mCurrentTab.owner = null;
-
-            var t = document.createElementNS(NS_XUL, "tab");
-
-            let aURIObject = null;
-            try {
-              aURIObject = Services.io.newURI(aURI || "about:blank");
-            } catch (ex) { /* we'll try to fix up this URL later */ }
-
-            var uriIsAboutBlank = !aURI || aURI == "about:blank";
-
-            if (!aURI || isBlankPageURL(aURI))
-              t.setAttribute("label", this.mStringBundle.getString("tabs.emptyTabTitle"));
-            else
-              t.setAttribute("label", aURI);
-
-            t.setAttribute("crop", "end");
-            t.setAttribute("validate", "never"); //PMed
-            t.setAttribute("onerror", "this.removeAttribute('image');");
-
-            if (aSkipBackgroundNotify) {
-              t.setAttribute("skipbackgroundnotify", true);
-            }
-
-            t.className = "tabbrowser-tab";
-
-            this.tabContainer._unlockTabSizing();
-
-            // When overflowing, new tabs are scrolled into view smoothly, which
-            // doesn't go well together with the width transition. So we skip the
-            // transition in that case.
-            let animate = !aSkipAnimation &&
-                          this.tabContainer.getAttribute("overflow") != "true" &&
-                          Services.prefs.getBoolPref("browser.tabs.animate");
-            if (!animate) {
-              t.setAttribute("fadein", "true");
-              setTimeout(function (tabContainer) {
-                tabContainer._handleNewTab(t);
-              }, 0, this.tabContainer);
-            }
-
-            // invalidate caches
-            this._browsers = null;
-            this._visibleTabs = null;
-
-            this.tabContainer.appendChild(t);
-
-            // If this new tab is owned by another, assert that relationship
-            if (aOwner)
-              t.owner = aOwner;
-
-            var b = document.createElementNS(
-              "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul",
-                                             "browser");
-            b.setAttribute("type", "content-targetable");
-            b.setAttribute("message", "true");
-            b.setAttribute("contextmenu", this.getAttribute("contentcontextmenu"));
-            b.setAttribute("tooltip", this.getAttribute("contenttooltip"));
-
-            if (Services.prefs.getPrefType("browser.tabs.remote") == Services.prefs.PREF_BOOL &&
-                Services.prefs.getBoolPref("browser.tabs.remote")) {
-              b.setAttribute("remote", "true");
-            }
-
-            if (window.gShowPageResizers && document.getElementById("addon-bar").collapsed &&
-                window.windowState == window.STATE_NORMAL) {
-              b.setAttribute("showresizer", "true");
-            }
-
-            if (aOpener) {
-              b.QueryInterface(Ci.nsIFrameLoaderOwner).presetOpenerWindow(aOpener);
-            }
-
-            if (this.hasAttribute("autocompletepopup"))
-              b.setAttribute("autocompletepopup", this.getAttribute("autocompletepopup"));
-            b.setAttribute("autoscrollpopup", this._autoScrollPopup.id);
-
-            if (this.hasAttribute("datetimepicker")) {
-              b.setAttribute("datetimepicker", this.getAttribute("datetimepicker"));
-            }
-            
-            if (this.hasAttribute("authdosprotected")) {
-              b.setAttribute("authdosprotected", this.getAttribute("authdosprotected"));
-            }
-
-            // Create the browserStack container
-            var stack = document.createElementNS(NS_XUL, "stack");
-            stack.className = "browserStack";
-            stack.appendChild(b);
-            stack.setAttribute("flex", "1");
-
-            // Create the browserContainer
-            var browserContainer = document.createElementNS(NS_XUL, "vbox");
-            browserContainer.className = "browserContainer";
-            browserContainer.appendChild(stack);
-            browserContainer.setAttribute("flex", "1");
-
-            // Create the sidebar container
-            var browserSidebarContainer = document.createElementNS(NS_XUL,
-                                                                   "hbox");
-            browserSidebarContainer.className = "browserSidebarContainer";
-            browserSidebarContainer.appendChild(browserContainer);
-            browserSidebarContainer.setAttribute("flex", "1");
-
-            // Add the Message and the Browser to the box
-            var notificationbox = document.createElementNS(NS_XUL,
-                                                           "notificationbox");
-            notificationbox.setAttribute("flex", "1");
-            notificationbox.appendChild(browserSidebarContainer);
-
-            var position = this.tabs.length - 1;
-            var uniqueId = "panel" + Date.now() + position;
-            notificationbox.id = uniqueId;
-            t.linkedPanel = uniqueId;
-            t.linkedBrowser = b;
-            this._tabForBrowser.set(b, t);
-            t._tPos = position;
-            this.tabContainer._setPositionalAttributes();
-
-            // Prevent the superfluous initial load of a blank document
-            // if we're going to load something other than about:blank.
-            if (!uriIsAboutBlank) {
-              b.setAttribute("nodefaultsrc", "true");
-            }
-
-            // NB: this appendChild call causes us to run constructors for the
-            // browser element, which fires off a bunch of notifications. Some
-            // of those notifications can cause code to run that inspects our
-            // state, so it is important that the tab element is fully
-            // initialized by this point.
-            this.mPanelContainer.appendChild(notificationbox);
-
-            this.tabContainer.updateVisibility();
-
-            // wire up a progress listener for the new browser object.
-            var tabListener = this.mTabProgressListener(t, b, uriIsAboutBlank);
-            const filter = Components.classes["@mozilla.org/appshell/component/browser-status-filter;1"]
-                                     .createInstance(Components.interfaces.nsIWebProgress);
-            filter.addProgressListener(tabListener, Components.interfaces.nsIWebProgress.NOTIFY_ALL);
-            b.webProgress.addProgressListener(filter, Components.interfaces.nsIWebProgress.NOTIFY_ALL);
-            this.mTabListeners[position] = tabListener;
-            this.mTabFilters[position] = filter;
-
-            b._fastFind = this.fastFind;
-            b.droppedLinkHandler = handleDroppedLink;
-
-            // If we just created a new tab that loads the default
-            // newtab url, swap in a preloaded page if possible.
-            // Do nothing if we're a private window.
-            let docShellsSwapped = false;
-            if (aURI == BROWSER_NEW_TAB_URL &&
-                !PrivateBrowsingUtils.isWindowPrivate(window)) {
-              docShellsSwapped = gBrowserNewTabPreloader.newTab(t);
-            }
-
-            // Dispatch a new tab notification.  We do this once we're
-            // entirely done, so that things are in a consistent state
-            // even if the event listener opens or closes tabs.
-            var evt = document.createEvent("Events");
-            evt.initEvent("TabOpen", true, false);
-            t.dispatchEvent(evt);
-
-            if (aOriginPrincipal && aURI) {
-              let {URI_INHERITS_SECURITY_CONTEXT} = Ci.nsIProtocolHandler;
-              // Unless we know for sure we're not inheriting principals,
-              // force the about:blank viewer to have the right principal:
-              if (!aURIObject ||
-                  (Services.io.getProtocolFlags(aURIObject.scheme) & URI_INHERITS_SECURITY_CONTEXT)) {
-                b.createAboutBlankContentViewer(aOriginPrincipal);
-              }
-            }
-
-            // If we didn't swap docShells with a preloaded browser
-            // then let's just continue loading the page normally.
-            if (!docShellsSwapped && !uriIsAboutBlank) {
-              // pretend the user typed this so it'll be available till
-              // the document successfully loads
-              if (aURI && gInitialPages.indexOf(aURI) == -1)
-                b.userTypedValue = aURI;
-
-              let flags = Ci.nsIWebNavigation.LOAD_FLAGS_NONE;
-              if (aAllowThirdPartyFixup) {
-                flags |= Ci.nsIWebNavigation.LOAD_FLAGS_ALLOW_THIRD_PARTY_FIXUP;
-                flags |= Ci.nsIWebNavigation.LOAD_FLAGS_FIXUP_SCHEME_TYPOS;
-              }
-              if (aFromExternal)
-                flags |= Ci.nsIWebNavigation.LOAD_FLAGS_FROM_EXTERNAL;
-              try {
-                b.loadURIWithFlags(aURI, {
-                                   flags: flags,
-                                   triggeringPrincipal: aTriggeringPrincipal,
-                                   referrerURI: aReferrerURI,
-                                   referrerPolicy: aReferrerPolicy,
-                                   charset: aCharset,
-                                   postData: aPostData,
-                                   });
-              } catch (ex) {
-                Cu.reportError(ex);
-              }
-            }
-
-            // We start our browsers out as inactive, and then maintain
-            // activeness in the tab switcher.
-            b.docShellIsActive = false;
-
-            // When addTab() is called with an URL that is not "about:blank" we
-            // set the "nodefaultsrc" attribute that prevents a frameLoader
-            // from being created as soon as the linked <browser> is inserted
-            // into the DOM. We thus have to register the new outerWindowID
-            // for non-remote browsers after we have called browser.loadURI().
-            //
-            // Note: Only do this of we still have a docShell. The TabOpen
-            // event was dispatched above and a gBrowser.removeTab() call from
-            // one of its listeners could cause us to fail here.
-            if (Services.prefs.getPrefType("browser.tabs.remote") == Services.prefs.PREF_BOOL &&
-               !Services.prefs.getBoolPref("browser.tabs.remote")
-               && b.docShell) {
-              this._outerWindowIDBrowserMap.set(b.outerWindowID, b);
-            }
-
-            // Check if we're opening a tab related to the current tab and
-            // move it to after the current tab.
-            // aReferrerURI is null or undefined if the tab is opened from
-            // an external application or bookmark, i.e. somewhere other
-            // than the current tab.
-            if ((aRelatedToCurrent == null ? aReferrerURI : aRelatedToCurrent) &&
-                Services.prefs.getBoolPref("browser.tabs.insertRelatedAfterCurrent")) {
-              let newTabPos = (this._lastRelatedTab ||
-                               this.selectedTab)._tPos + 1;
-              if (this._lastRelatedTab)
-                this._lastRelatedTab.owner = null;
-              else
-                t.owner = this.selectedTab;
-              this.moveTabTo(t, newTabPos);
-              this._lastRelatedTab = t;
-            }
-
-            if (animate) {
-              requestAnimationFrame(function () {
-                this.tabContainer._handleTabTelemetryStart(t, aURI);
-
-                // kick the animation off
-                t.setAttribute("fadein", "true");
-
-                // This call to adjustTabstrip is redundant but needed so that
-                // when opening a second tab, the first tab's close buttons
-                // appears immediately rather than when the transition ends.
-                if (this.tabs.length - this._removingTabs.length == 2)
-                  this.tabContainer.adjustTabstrip();
-              }.bind(this));
-            }
-
-            return t;
-          ]]>
-        </body>
-      </method>
-
-      <method name="warnAboutClosingTabs">
-      <parameter name="aCloseTabs"/>
-      <parameter name="aTab"/>
-      <body>
-        <![CDATA[
-          var tabsToClose;
-          switch (aCloseTabs) {
-            case this.closingTabsEnum.ALL:
-              // If there are multiple windows, pinned tabs will be closed, so
-              // we warn about them, too; if there is just one window, pinned
-              // tabs should come back on restart, so exclude them from warning.
-              var numberOfWindows = 0;
-              var browserEnum = Services.wm.getEnumerator("navigator:browser");
-              while (browserEnum.hasMoreElements() && numberOfWindows < 2) {
-                numberOfWindows++;
-                browserEnum.getNext();
-              }
-              if (numberOfWindows > 1) {
-                tabsToClose = this.tabs.length - this._removingTabs.length
-              }
-              else {
-                tabsToClose = this.tabs.length - this._removingTabs.length -
-                              gBrowser._numPinnedTabs;
-              }
-              break;
-            case this.closingTabsEnum.OTHER:
-              tabsToClose = this.visibleTabs.length - 1 - gBrowser._numPinnedTabs;
-              break;
-            case this.closingTabsEnum.TO_END:
-              if (!aTab)
-                throw new Error("Required argument missing: aTab");
-
-              tabsToClose = this.getTabsToTheEndFrom(aTab).length;
-              break;
-            default:
-              throw new Error("Invalid argument: " + aCloseTabs);
-          }
-
-          if (tabsToClose <= 1)
-            return true;
-
-          const pref = aCloseTabs == this.closingTabsEnum.ALL ?
-                       "browser.tabs.warnOnClose" : "browser.tabs.warnOnCloseOtherTabs";
-          var shouldPrompt = Services.prefs.getBoolPref(pref);
-          if (!shouldPrompt)
-            return true;
-
-          var ps = Services.prompt;
-
-          // default to true: if it were false, we wouldn't get this far
-          var warnOnClose = { value: true };
-          var bundle = this.mStringBundle;
-
-          // focus the window before prompting.
-          // this will raise any minimized window, which will
-          // make it obvious which window the prompt is for and will
-          // solve the problem of windows "obscuring" the prompt.
-          // see bug #350299 for more details
-          window.focus();
-          var buttonPressed =
-            ps.confirmEx(window,
-                         bundle.getString("tabs.closeWarningTitle"),
-                         bundle.getFormattedString("tabs.closeWarningMultipleTabs",
-                                                   [tabsToClose]),
-                         (ps.BUTTON_TITLE_IS_STRING * ps.BUTTON_POS_0)
-                         + (ps.BUTTON_TITLE_CANCEL * ps.BUTTON_POS_1),
-                         bundle.getString("tabs.closeButtonMultiple"),
-                         null, null,
-                         aCloseTabs == this.closingTabsEnum.ALL ?
-                           bundle.getString("tabs.closeWarningPromptMe") : null,
-                         warnOnClose);
-          var reallyClose = (buttonPressed == 0);
-
-          // don't set the prefs unless they press OK and have unchecked the box
-          if (aCloseTabs == this.closingTabsEnum.ALL && reallyClose && !warnOnClose.value) {
-            Services.prefs.setBoolPref("browser.tabs.warnOnClose", false);
-				Services.prefs.setBoolPref("browser.tabs.warnOnCloseOtherTabs", false);
-				}
-          return reallyClose;
-        ]]>
-      </body>
-      </method>
-
-      <method name="getTabsToTheEndFrom">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            var tabsToEnd = [];
-            let tabs = this.visibleTabs;
-            for (let i = tabs.length - 1; tabs[i] != aTab && i >= 0; --i) {
-              tabsToEnd.push(tabs[i]);
-            }
-            return tabsToEnd.reverse();
-          ]]>
-        </body>
-      </method>
-
-      <method name="removeTabsToTheEndFrom">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            if (this.warnAboutClosingTabs(this.closingTabsEnum.TO_END, aTab)) {
-              let tabs = this.getTabsToTheEndFrom(aTab);
-              for (let i = tabs.length - 1; i >= 0; --i) {
-                this.removeTab(tabs[i], {animate: true});
-              }
-            }
-          ]]>
-        </body>
-      </method>
-
-      <method name="removeAllTabsBut">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            if (aTab.pinned)
-              return;
-
-            if (this.warnAboutClosingTabs(this.closingTabsEnum.OTHER)) {
-              let tabs = this.visibleTabs;
-              this.selectedTab = aTab;
-
-              for (let i = tabs.length - 1; i >= 0; --i) {
-                if (tabs[i] != aTab && !tabs[i].pinned)
-                  this.removeTab(tabs[i]);
-              }
-            }
-          ]]>
-        </body>
-      </method>
-
-      <method name="removeCurrentTab">
-        <parameter name="aParams"/>
-        <body>
-          <![CDATA[
-            this.removeTab(this.mCurrentTab, aParams);
-          ]]>
-        </body>
-      </method>
-
-      <field name="_removingTabs">
-        []
-      </field>
-
-      <method name="removeTab">
-        <parameter name="aTab"/>
-        <parameter name="aParams"/>
-        <body>
-          <![CDATA[
-            if (aParams) {
-              var animate = aParams.animate;
-              var byMouse = aParams.byMouse;
-            }
-
-            // Handle requests for synchronously removing an already
-            // asynchronously closing tab.
-            if (!animate &&
-                aTab.closing) {
-              this._endRemoveTab(aTab);
-              return;
-            }
-
-            var isLastTab = (this.tabs.length - this._removingTabs.length == 1);
-
-            if (!this._beginRemoveTab(aTab, false, null, true))
-              return;
-
-            if (!aTab.pinned && !aTab.hidden && aTab._fullyOpen && byMouse)
-              this.tabContainer._lockTabSizing(aTab);
-            else
-              this.tabContainer._unlockTabSizing();
-
-            if (!animate /* the caller didn't opt in */ ||
-                isLastTab ||
-                aTab.pinned ||
-                aTab.hidden ||
-                this._removingTabs.length > 3 /* don't want lots of concurrent animations */ ||
-                aTab.getAttribute("fadein") != "true" /* fade-in transition hasn't been triggered yet */ ||
-                window.getComputedStyle(aTab).maxWidth == "0.1px" /* fade-in transition hasn't moved yet */ ||
-                !Services.prefs.getBoolPref("browser.tabs.animate")) {
-              this._endRemoveTab(aTab);
-              return;
-            }
-
-            this.tabContainer._handleTabTelemetryStart(aTab);
-
-            this._blurTab(aTab);
-            aTab.style.maxWidth = ""; // ensure that fade-out transition happens
-            aTab.removeAttribute("fadein");
-
-            if (this.tabs.length - this._removingTabs.length == 1) {
-              // The second tab just got closed and we will end up with a single
-              // one. Remove the first tab's close button immediately (if needed)
-              // rather than after the tabclose animation ends.
-              this.tabContainer.adjustTabstrip();
-            }
-
-            setTimeout(function (tab, tabbrowser) {
-              if (tab.parentNode &&
-                  window.getComputedStyle(tab).maxWidth == "0.1px") {
-                NS_ASSERT(false, "Giving up waiting for the tab closing animation to finish (bug 608589)");
-                tabbrowser._endRemoveTab(tab);
-              }
-            }, 3000, aTab, this);
-          ]]>
-        </body>
-      </method>
-
-      <!-- Tab close requests are ignored if the window is closing anyway,
-           e.g. when holding Ctrl+W. -->
-      <field name="_windowIsClosing">
-        false
-      </field>
-
-      <method name="_beginRemoveTab">
-        <parameter name="aTab"/>
-        <parameter name="aTabWillBeMoved"/>
-        <parameter name="aCloseWindowWithLastTab"/>
-        <parameter name="aCloseWindowFastpath"/>
-        <body>
-          <![CDATA[
-            if (aTab.closing ||
-                aTab._pendingPermitUnload ||
-                this._windowIsClosing)
-              return false;
-
-            var browser = this.getBrowserForTab(aTab);
-
-            if (!aTabWillBeMoved) {
-              let ds = browser.docShell;
-              if (ds && ds.contentViewer) {
-                // We need to block while calling permitUnload() because it
-                // processes the event queue and may lead to another removeTab()
-                // call before permitUnload() even returned.
-                aTab._pendingPermitUnload = true;
-                let permitUnload = ds.contentViewer.permitUnload();
-                delete aTab._pendingPermitUnload;
-
-                if (!permitUnload)
-                  return false;
-              }
-            }
-
-            var closeWindow = false;
-            var newTab = false;
-            if (this.tabs.length - this._removingTabs.length == 1) {
-              closeWindow = aCloseWindowWithLastTab != null ? aCloseWindowWithLastTab :
-                            !window.toolbar.visible ||
-                              this.tabContainer._closeWindowWithLastTab;
-
-              // Closing the tab and replacing it with a blank one is notably slower
-              // than closing the window right away. If the caller opts in, take
-              // the fast path.
-              if (closeWindow &&
-                  aCloseWindowFastpath &&
-                  this._removingTabs.length == 0 &&
-                  (this._windowIsClosing = window.closeWindow(true, window.warnAboutClosingWindow)))
-                return null;
-
-              newTab = true;
-            }
-
-            aTab.closing = true;
-            this._removingTabs.push(aTab);
-            this._visibleTabs = null; // invalidate cache
-            if (newTab)
-              this.addTab(BROWSER_NEW_TAB_URL, {skipAnimation: true});
-            else
-              this.tabContainer.updateVisibility();
-
-            // We're committed to closing the tab now.
-            // Dispatch a notification.
-            // We dispatch it before any teardown so that event listeners can
-            // inspect the tab that's about to close.
-            var evt = document.createEvent("UIEvent");
-            evt.initUIEvent("TabClose", true, false, window, aTabWillBeMoved ? 1 : 0);
-            aTab.dispatchEvent(evt);
-
-            if (!gMultiProcessBrowser) {
-              // Prevent this tab from showing further dialogs, since we're closing it
-              var windowUtils = browser.contentWindow.QueryInterface(Ci.nsIInterfaceRequestor).
-                                getInterface(Ci.nsIDOMWindowUtils);
-              windowUtils.disableDialogs();
-            }
-
-            // Remove the tab's filter and progress listener.
-            const filter = this.mTabFilters[aTab._tPos];
-
-            browser.webProgress.removeProgressListener(filter);
-
-            filter.removeProgressListener(this.mTabListeners[aTab._tPos]);
-            this.mTabListeners[aTab._tPos].destroy();
-
-            if (browser.registeredOpenURI && !aTabWillBeMoved) {
-              this._placesAutocomplete.unregisterOpenPage(browser.registeredOpenURI);
-              delete browser.registeredOpenURI;
-            }
-
-            // We are no longer the primary content area.
-            browser.setAttribute("type", "content-targetable");
-
-            // Remove this tab as the owner of any other tabs, since it's going away.
-            Array.forEach(this.tabs, function (tab) {
-              if ("owner" in tab && tab.owner == aTab)
-                // |tab| is a child of the tab we're removing, make it an orphan
-                tab.owner = null;
-            });
-
-            aTab._endRemoveArgs = [closeWindow, newTab];
-            return true;
-          ]]>
-        </body>
-      </method>
-
-      <method name="_endRemoveTab">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            if (!aTab || !aTab._endRemoveArgs)
-              return;
-
-            var [aCloseWindow, aNewTab] = aTab._endRemoveArgs;
-            aTab._endRemoveArgs = null;
-
-            if (this._windowIsClosing) {
-              aCloseWindow = false;
-              aNewTab = false;
-            }
-
-            this._lastRelatedTab = null;
-
-            // update the UI early for responsiveness
-            aTab.collapsed = true;
-            this.tabContainer._fillTrailingGap();
-            this._blurTab(aTab);
-
-            this._removingTabs.splice(this._removingTabs.indexOf(aTab), 1);
-
-            if (aCloseWindow) {
-              this._windowIsClosing = true;
-              while (this._removingTabs.length)
-                this._endRemoveTab(this._removingTabs[0]);
-            } else if (!this._windowIsClosing) {
-              if (aNewTab)
-                focusAndSelectUrlBar();
-
-              // workaround for bug 345399
-              this.tabContainer.mTabstrip._updateScrollButtonsDisabledState();
-            }
-
-            // We're going to remove the tab and the browser now.
-            // Clean up mTabFilters and mTabListeners now rather than in
-            // _beginRemoveTab, so that their size is always in sync with the
-            // number of tabs and browsers (the xbl destructor depends on this).
-            this.mTabFilters.splice(aTab._tPos, 1);
-            this.mTabListeners.splice(aTab._tPos, 1);
-
-            var browser = this.getBrowserForTab(aTab);
-            this._outerWindowIDBrowserMap.delete(browser.outerWindowID);
-
-            // Because of the way XBL works (fields just set JS
-            // properties on the element) and the code we have in place
-            // to preserve the JS objects for any elements that have
-            // JS properties set on them, the browser element won't be
-            // destroyed until the document goes away.  So we force a
-            // cleanup ourselves.
-            // This has to happen before we remove the child so that the
-            // XBL implementation of nsIObserver still works.
-            browser.destroy();
-
-            if (browser == this.mCurrentBrowser)
-              this.mCurrentBrowser = null;
-
-            var wasPinned = aTab.pinned;
-
-            // Invalidate browsers cache, as the tab is removed from the
-            // tab container.
-            this._browsers = null;
-
-            // Remove the tab ...
-            this.tabContainer.removeChild(aTab);
-
-            // ... and fix up the _tPos properties immediately.
-            for (let i = aTab._tPos; i < this.tabs.length; i++)
-              this.tabs[i]._tPos = i;
-
-            if (!this._windowIsClosing) {
-              if (wasPinned)
-                this.tabContainer._positionPinnedTabs();
-
-              // update tab close buttons state
-              this.tabContainer.adjustTabstrip();
-
-              setTimeout(function(tabs) {
-                tabs._lastTabClosedByMouse = false;
-              }, 0, this.tabContainer);
-            }
-
-            // Pale Moon: if resizing immediately, select the tab immediately to the left
-            // instead of the right (if not leftmost) to prevent focus swap and
-            // "selected tab not under cursor"
-            // FIXME: Tabs must be sliding in from the left for this, or it'd unfocus
-            // in the other direction! Disabled for now. Is there an easier way? :hover?
-            // Is this even needed when resizing immediately?...
-            
-            //if (Services.prefs.getBoolPref("browser.tabs.resize_immediately")) {
-            //  if (this.selectedTab._tPos > 1) {
-            //    let newPos = this.selectedTab._tPos - 1;
-            //    this.selectedTab = this.tabs[newPos];
-            //  }
-            //}
-
-            // update tab positional properties and attributes
-            this.selectedTab._selected = true;
-            this.tabContainer._setPositionalAttributes();
-
-            // Removing the panel requires fixing up selectedPanel immediately
-            // (see below), which would be hindered by the potentially expensive
-            // browser removal. So we remove the browser and the panel in two
-            // steps.
-
-            var panel = this.getNotificationBox(browser);
-
-            // This will unload the document. An unload handler could remove
-            // dependant tabs, so it's important that the tabbrowser is now in
-            // a consistent state (tab removed, tab positions updated, etc.).
-            browser.parentNode.removeChild(browser);
-
-            // Release the browser in case something is erroneously holding a
-            // reference to the tab after its removal.
-            this._tabForBrowser.delete(aTab.linkedBrowser);
-            aTab.linkedBrowser = null;
-
-            // As the browser is removed, the removal of a dependent document can
-            // cause the whole window to close. So at this point, it's possible
-            // that the binding is destructed.
-            if (this.mTabBox) {
-              let selectedPanel = this.mTabBox.selectedPanel;
-
-              this.mPanelContainer.removeChild(panel);
-
-              // Under the hood, a selectedIndex attribute controls which panel
-              // is displayed. Removing a panel A which precedes the selected
-              // panel B makes selectedIndex point to the panel next to B. We
-              // need to explicitly preserve B as the selected panel.
-              this.mTabBox.selectedPanel = selectedPanel;
-            }
-
-            if (aCloseWindow)
-              this._windowIsClosing = closeWindow(true, window.warnAboutClosingWindow);
-          ]]>
-        </body>
-      </method>
-
-      <method name="_blurTab">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            if (!aTab.selected)
-              return;
-
-            if (aTab.owner &&
-                !aTab.owner.hidden &&
-                !aTab.owner.closing &&
-                Services.prefs.getBoolPref("browser.tabs.selectOwnerOnClose")) {
-              this.selectedTab = aTab.owner;
-              return;
-            }
-
-            // Switch to a visible tab unless there aren't any others remaining
-            let remainingTabs = this.visibleTabs;
-            let numTabs = remainingTabs.length;
-            if (numTabs == 0 || numTabs == 1 && remainingTabs[0] == aTab) {
-              remainingTabs = Array.filter(this.tabs, function(tab) {
-                return !tab.closing;
-              }, this);
-            }
-
-            // Try to find a remaining tab that comes after the given tab
-            var tab = aTab;
-            do {
-              tab = tab.nextSibling;
-            } while (tab && remainingTabs.indexOf(tab) == -1);
-
-            if (!tab) {
-              tab = aTab;
-
-              do {
-                tab = tab.previousSibling;
-              } while (tab && remainingTabs.indexOf(tab) == -1);
-            }
-
-            this.selectedTab = tab;
-          ]]>
-        </body>
-      </method>
-
-      <method name="swapNewTabWithBrowser">
-        <parameter name="aNewTab"/>
-        <parameter name="aBrowser"/>
-        <body>
-          <![CDATA[
-            // The browser must be standalone.
-            if (aBrowser.getTabBrowser())
-              throw Cr.NS_ERROR_INVALID_ARG;
-
-            // The tab is definitely not loading.
-            aNewTab.removeAttribute("busy");
-            if (aNewTab.selected) {
-              this.mIsBusy = false;
-            }
-
-            this._swapBrowserDocShells(aNewTab, aBrowser);
-
-            // Update the new tab's title.
-            this.setTabTitle(aNewTab);
-
-            if (aNewTab.selected) {
-              this.updateCurrentBrowser(true);
-            }
-          ]]>
-        </body>
-      </method>
-
-      <method name="swapBrowsersAndCloseOther">
-        <parameter name="aOurTab"/>
-        <parameter name="aOtherTab"/>
-        <body>
-          <![CDATA[
-            // Do not allow transfering a private tab to a non-private window
-            // and vice versa.
-            if (PrivateBrowsingUtils.isWindowPrivate(window) !=
-                PrivateBrowsingUtils.isWindowPrivate(aOtherTab.ownerDocument.defaultView))
-              return;
-
-            // That's gBrowser for the other window, not the tab's browser!
-            var remoteBrowser = aOtherTab.ownerDocument.defaultView.gBrowser;
-            var isPending = aOtherTab.hasAttribute("pending");
-
-            // Expedite the removal of the icon if it was already scheduled.
-            if (aOtherTab._soundPlayingAttrRemovalTimer) {
-              clearTimeout(aOtherTab._soundPlayingAttrRemovalTimer);
-              aOtherTab._soundPlayingAttrRemovalTimer = 0;
-              aOtherTab.removeAttribute("soundplaying");
-              remoteBrowser._tabAttrModified(aOtherTab, ["soundplaying"]);
-            }
-
-            // First, start teardown of the other browser.  Make sure to not
-            // fire the beforeunload event in the process.  Close the other
-            // window if this was its last tab.
-            if (!remoteBrowser._beginRemoveTab(aOtherTab, true, true))
-              return;
-
-            let ourBrowser = this.getBrowserForTab(aOurTab);
-            let otherBrowser = aOtherTab.linkedBrowser;
-
-            let modifiedAttrs = [];
-            if (aOtherTab.hasAttribute("muted")) {
-              aOurTab.setAttribute("muted", "true");
-              aOurTab.muteReason = aOtherTab.muteReason;
-              ourBrowser.mute();
-              modifiedAttrs.push("muted");
-            }
-            if (aOtherTab.hasAttribute("soundplaying")) {
-              aOurTab.setAttribute("soundplaying", "true");
-              modifiedAttrs.push("soundplaying");
-            }
-
-            // If the other tab is pending (i.e. has not been restored, yet)
-            // then do not switch docShells but retrieve the other tab's state
-            // and apply it to our tab.
-            if (isPending) {
-              let ss = Cc["@mozilla.org/browser/sessionstore;1"]
-                         .getService(Ci.nsISessionStore)
-              ss.setTabState(aOurTab, ss.getTabState(aOtherTab));
-
-              // Make sure to unregister any open URIs.
-              this._swapRegisteredOpenURIs(ourBrowser, otherBrowser);
-            } else {
-              // Workarounds for bug 458697
-              // Icon might have been set on DOMLinkAdded, don't override that.
-              if (!ourBrowser.mIconURL && otherBrowser.mIconURL)
-                this.setIcon(aOurTab, otherBrowser.mIconURL, otherBrowser.contentPrincipal);
-              var isBusy = aOtherTab.hasAttribute("busy");
-              if (isBusy) {
-                aOurTab.setAttribute("busy", "true");
-                modifiedAttrs.push("busy");
-                if (aOurTab.selected)
-                  this.mIsBusy = true;
-              }
-
-              this._swapBrowserDocShells(aOurTab, otherBrowser);
-            }
-
-            // Finish tearing down the tab that's going away.
-            remoteBrowser._endRemoveTab(aOtherTab);
-
-            if (isBusy)
-              this.setTabTitleLoading(aOurTab);
-            else
-              this.setTabTitle(aOurTab);
-
-            // If the tab was already selected (this happpens in the scenario
-            // of replaceTabWithWindow), notify onLocationChange, etc.
-            if (aOurTab.selected)
-              this.updateCurrentBrowser(true);
-
-            if (modifiedAttrs.length) {
-              this._tabAttrModified(aOurTab, modifiedAttrs);
-            }
-          ]]>
-        </body>
-      </method>
-
-      <method name="_swapBrowserDocShells">
-        <parameter name="aOurTab"/>
-        <parameter name="aOtherBrowser"/>
-        <body>
-          <![CDATA[
-            // Unhook our progress listener
-            let index = aOurTab._tPos;
-            const filter = this.mTabFilters[index];
-            let tabListener = this.mTabListeners[index];
-            let ourBrowser = this.getBrowserForTab(aOurTab);
-            ourBrowser.webProgress.removeProgressListener(filter);
-            filter.removeProgressListener(tabListener);
-
-            // Make sure to unregister any open URIs.
-            this._swapRegisteredOpenURIs(ourBrowser, aOtherBrowser);
-
-            // Unmap old outerWindowIDs.
-            this._outerWindowIDBrowserMap.delete(ourBrowser.outerWindowID);
-            let remoteBrowser = aOtherBrowser.ownerDocument.defaultView.gBrowser;
-            if (remoteBrowser) {
-              remoteBrowser._outerWindowIDBrowserMap.delete(aOtherBrowser.outerWindowID);
-            }
-            // Swap the docshells
-            ourBrowser.swapDocShells(aOtherBrowser);
-
-            // Register new outerWindowIDs.
-            this._outerWindowIDBrowserMap.set(ourBrowser.outerWindowID, ourBrowser);
-            if (remoteBrowser) {
-              remoteBrowser._outerWindowIDBrowserMap.set(aOtherBrowser.outerWindowID, aOtherBrowser);
-            }
-            // Restore the progress listener
-            this.mTabListeners[index] = tabListener =
-              this.mTabProgressListener(aOurTab, ourBrowser, false);
-
-            const notifyAll = Ci.nsIWebProgress.NOTIFY_ALL;
-            filter.addProgressListener(tabListener, notifyAll);
-            ourBrowser.webProgress.addProgressListener(filter, notifyAll);
-          ]]>
-        </body>
-      </method>
-
-      <method name="_swapRegisteredOpenURIs">
-        <parameter name="aOurBrowser"/>
-        <parameter name="aOtherBrowser"/>
-        <body>
-          <![CDATA[
-            // If the current URI is registered as open remove it from the list.
-            if (aOurBrowser.registeredOpenURI) {
-              this._placesAutocomplete.unregisterOpenPage(aOurBrowser.registeredOpenURI);
-              delete aOurBrowser.registeredOpenURI;
-            }
-
-            // If the other/new URI is registered as open then copy it over.
-            if (aOtherBrowser.registeredOpenURI) {
-              aOurBrowser.registeredOpenURI = aOtherBrowser.registeredOpenURI;
-              delete aOtherBrowser.registeredOpenURI;
-            }
-          ]]>
-        </body>
-      </method>
-
-      <method name="reloadAllTabs">
-        <body>
-          <![CDATA[
-            let tabs = this.visibleTabs;
-            let l = tabs.length;
-            for (var i = 0; i < l; i++) {
-              try {
-                this.getBrowserForTab(tabs[i]).reload();
-              } catch (e) {
-                // ignore failure to reload so others will be reloaded
-              }
-            }
-          ]]>
-        </body>
-      </method>
-
-      <method name="reloadTab">
-        <parameter name="aTab"/>
-        <body>
-          <![CDATA[
-            let browser = this.getBrowserForTab(aTab);
-            // Reset DOS mitigation for basic auth prompt
-            delete browser.authPromptCounter;
-            browser.reload();
-          ]]>
-        </body>
-      </method>
-
-      <method name="addProgressListener">
-        <parameter name="aListener"/>
-        <body>
-          <![CDATA[
-            if (arguments.length != 1) {
-              Components.utils.reportError("gBrowser.addProgressListener was " +
-                                           "called with a second argument, " +
-                                           "which is not supported. See bug " +
-                                           "608628.");
-            }
-
-            this.mProgressListeners.push(aListener);
-          ]]>
-        </body>
-      </method>
-
-      <method name="removeProgressListener">
-        <parameter name="aListener"/>
-        <body>
-          <![CDATA[
-            this.mProgressListeners =
-              this.mProgressListeners.filter(function (l) l != aListener);
-         ]]>
-        </body>
-      </method>
-
-      <method name="addTabsProgressListener">
-        <parameter name="aListener"/>
-        <body>
-          this.mTabsProgressListeners.push(aListener);
-        </body>
-      </method>
-
-      <method name="removeTabsProgressListener">
-        <parameter name="aListener"/>
-        <body>
-        <![CDATA[
-          this.mTabsProgressListeners =
-            this.mTabsProgressListeners.filter(function (l) l != aListener);
-        ]]>
-        </body>
-      </method>
-
-      <method name="getBrowserForTab">
-        <parameter name="aTab"/>
-        <body>
-        <![CDATA[
-          return aTab.linkedBrowser;
-        ]]>
-        </body>
-      </method>
-
-      <method name="showOnlyTheseTabs">
-        <parameter name="aTabs"/>
-        <body>
-        <![CDATA[
-          Array.forEach(this.tabs, function(tab) {
-            if (aTabs.indexOf(tab) == -1)
-              this.hideTab(tab);
-            else
-              this.showTab(tab);
-          }, this);
-
-          this.tabContainer._handleTabSelect(false);
-        ]]>
-        </body>
-      </method>
-
-      <method name="showTab">
-        <parameter name="aTab"/>
-        <body>
-        <![CDATA[
-          if (aTab.hidden) {
-            aTab.removeAttribute("hidden");
-            this._visibleTabs = null; // invalidate cache
-
-            this.tabContainer.adjustTabstrip();
-
-            this.tabContainer._setPositionalAttributes();
-
-            let event = document.createEvent("Events");
-            event.initEvent("TabShow", true, false);
-            aTab.dispatchEvent(event);
-          }
-        ]]>
-        </body>
-      </method>
-
-      <method name="hideTab">
-        <parameter name="aTab"/>
-        <body>
-        <![CDATA[
-          if (!aTab.hidden && !aTab.pinned && !aTab.selected &&
-              !aTab.closing) {
-            aTab.setAttribute("hidden", "true");
-            this._visibleTabs = null; // invalidate cache
-
-            this.tabContainer.adjustTabstrip();
-
-            this.tabContainer._setPositionalAttributes();
-
-            let event = document.createEvent("Events");
-            event.initEvent("TabHide", true, false);
-            aTab.dispatchEvent(event);
-          }
-        ]]>
-        </body>
-      </method>
-
-      <method name="selectTabAtIndex">
-        <parameter name="aIndex"/>
-        <parameter name="aEvent"/>
-        <body>
-        <![CDATA[
-          let tabs = this.visibleTabs;
-
-          // count backwards for aIndex < 0
-          if (aIndex < 0)
-            aIndex += tabs.length;
-
-          if (aIndex >= 0 && aIndex < tabs.length)
-            this.selectedTab = tabs[aIndex];
-
-          if (aEvent) {
-            aEvent.preventDefault();
-            aEvent.stopPropagation();
-          }
-        ]]>
-        </body>
-      </method>
-
-      <property name="selectedTab">
-        <getter>
-          return this.mCurrentTab;
-        </getter>
-        <setter>
-          <![CDATA[
-          if (gNavToolbox.collapsed) {
-            return this.mTabBox.selectedTab;
-          }         
-          // Update the tab
-          this.mTabBox.selectedTab = val;
-          return val;
-          ]]>
-        </setter>
-      </property>
-
-      <property name="selectedBrowser"
-                onget="return this.mCurrentBrowser;"
-                readonly="true"/>
-
-      <property name="browsers" readonly="true">
-       <getter>
-          <![CDATA[
-            return this._browsers ||
-                   (this._browsers = Array.map(this.tabs, function (tab) tab.linkedBrowser));
-          ]]>
-        </getter>
-      </property>
-      <field name="_browsers">null</field>
-
-      <!-- Moves a tab to a new browser window, unless it's already the only tab
-           in the current window, in which case this will do nothing. -->
-      <method name="replaceTabWithWindow">
-        <parameter name="aTab"/>
-        <parameter name="aOptions"/>
-        <body>
-          <![CDATA[
-            if (this.tabs.length == 1)
-              return null;
-
-            var options = "chrome,dialog=no,all";
-            for (var name in aOptions)
-              options += "," + name + "=" + aOptions[name];
-
-            // tell a new window to take the "dropped" tab
-            return window.openDialog(getBrowserURL(), "_blank", options, aTab);
-          ]]>
-        </body>
-      </method>
-
-      <method name="moveTabTo">
-        <parameter name="aTab"/>
-        <parameter name="aIndex"/>
-        <body>
-        <![CDATA[
-          var oldPosition = aTab._tPos;
-          if (oldPosition == aIndex)
-            return;
-
-          // Don't allow mixing pinned and unpinned tabs.
-          if (aTab.pinned)
-            aIndex = Math.min(aIndex, this._numPinnedTabs - 1);
-          else
-            aIndex = Math.max(aIndex, this._numPinnedTabs);
-          if (oldPosition == aIndex)
-            return;
-
-          this._lastRelatedTab = null;
-
-          this.mTabFilters.splice(aIndex, 0, this.mTabFilters.splice(aTab._tPos, 1)[0]);
-          this.mTabListeners.splice(aIndex, 0, this.mTabListeners.splice(aTab._tPos, 1)[0]);
-
-          let wasFocused = (document.activeElement == this.mCurrentTab);
-
-          aIndex = aIndex < aTab._tPos ? aIndex: aIndex+1;
-          this.mCurrentTab._selected = false;
-
-          // invalidate caches
-          this._browsers = null;
-          this._visibleTabs = null;
-
-          // use .item() instead of [] because dragging to the end of the strip goes out of
-          // bounds: .item() returns null (so it acts like appendChild), but [] throws
-          this.tabContainer.insertBefore(aTab, this.tabs.item(aIndex));
-
-          for (let i = 0; i < this.tabs.length; i++) {
-            this.tabs[i]._tPos = i;
-            this.tabs[i]._selected = false;
-          }
-          this.mCurrentTab._selected = true;
-
-          if (wasFocused)
-            this.mCurrentTab.focus();
-
-          this.tabContainer._handleTabSelect(false);
-
-          if (aTab.pinned)
-            this.tabContainer._positionPinnedTabs();
-
-          this.tabContainer._setPositionalAttributes();
-
-          var evt = document.createEvent("UIEvents");
-          evt.initUIEvent("TabMove", true, false, window, oldPosition);
-          aTab.dispatchEvent(evt);
-        ]]>
-        </body>
-      </method>
-
-      <method name="moveTabForward">
-        <body>
-          <![CDATA[
-            let nextTab = this.mCurrentTab.nextSibling;
-            while (nextTab && nextTab.hidden)
-              nextTab = nextTab.nextSibling;
-
-            if (nextTab)
-              this.moveTabTo(this.mCurrentTab, nextTab._tPos);
-            else if (this.arrowKeysShouldWrap)
-              this.moveTabToStart();
-          ]]>
-        </body>
-      </method>
-
-      <method name="moveTabBackward">
-        <body>
-          <![CDATA[
-            let previousTab = this.mCurrentTab.previousSibling;
-            while (previousTab && previousTab.hidden)
-              previousTab = previousTab.previousSibling;
-
-            if (previousTab)
-              this.moveTabTo(this.mCurrentTab, previousTab._tPos);
-            else if (this.arrowKeysShouldWrap)
-              this.moveTabToEnd();
-          ]]>
-        </body>
-      </method>
-
-      <method name="moveTabToStart">
-        <body>
-          <![CDATA[
-            var tabPos = this.mCurrentTab._tPos;
-            if (tabPos > 0)
-              this.moveTabTo(this.mCurrentTab, 0);
-          ]]>
-        </body>
-      </method>
-
-      <method name="moveTabToEnd">
-        <body>
-          <![CDATA[
-            var tabPos = this.mCurrentTab._tPos;
-            if (tabPos < this.browsers.length - 1)
-              this.moveTabTo(this.mCurrentTab, this.browsers.length - 1);
-          ]]>
-        </body>
-      </method>
-
-      <method name="moveTabOver">
-        <parameter name="aEvent"/>
-        <body>
-          <![CDATA[
-            var direction = window.getComputedStyle(this.parentNode, null).direction;
-            if ((direction == "ltr" && aEvent.keyCode == KeyEvent.DOM_VK_RIGHT) ||
-                (direction == "rtl" && aEvent.keyCode == KeyEvent.DOM_VK_LEFT))
-              this.moveTabForward();
-            else
-              this.moveTabBackward();
-          ]]>
-        </body>
-      </method>
-
-      <method name="duplicateTab">
-        <parameter name="aTab"/><!-- can be from a different window as well -->
-        <body>
-          <![CDATA[
-            return Cc["@mozilla.org/browser/sessionstore;1"]
-                     .getService(Ci.nsISessionStore)
-                     .duplicateTab(window, aTab);
-          ]]>
-        </body>
-      </method>
-
-      <!-- BEGIN FORWARDED BROWSER PROPERTIES.  IF YOU ADD A PROPERTY TO THE BROWSER ELEMENT
-           MAKE SURE TO ADD IT HERE AS WELL. -->
-      <property name="canGoBack"
-                onget="return this.mCurrentBrowser.canGoBack;"
-                readonly="true"/>
-
-      <property name="canGoForward"
-                onget="return this.mCurrentBrowser.canGoForward;"
-                readonly="true"/>
-
-      <method name="goBack">
-        <body>
-          <![CDATA[
-            return this.mCurrentBrowser.goBack();
-          ]]>
-        </body>
-      </method>
-
-      <method name="goForward">
-        <body>
-          <![CDATA[
-            return this.mCurrentBrowser.goForward();
-          ]]>
-        </body>
-      </method>
-
-      <method name="reload">
-        <body>
-          <![CDATA[
-            return this.mCurrentBrowser.reload();
-          ]]>
-        </body>
-      </method>
-
-      <method name="reloadWithFlags">
-        <parameter name="aFlags"/>
-        <body>
-          <![CDATA[
-            return this.mCurrentBrowser.reloadWithFlags(aFlags);
-          ]]>
-        </body>
-      </method>
-
-      <method name="stop">
-        <body>
-          <![CDATA[
-            return this.mCurrentBrowser.stop();
-          ]]>
-        </body>
-      </method>
-
-      <!-- throws exception for unknown schemes -->
-      <method name="loadURI">
-        <parameter name="aURI"/>
-        <parameter name="aReferrerURI"/>
-        <parameter name="aCharset"/>
-        <body>
-          <![CDATA[
-            return this.mCurrentBrowser.loadURI(aURI, aReferrerURI, aCharset);
-          ]]>
-        </body>
-      </method>
-
-      <!-- throws exception for unknown schemes -->
-      <method name="loadURIWithFlags">
-        <parameter name="aURI"/>
-        <parameter name="aFlags"/>
-        <parameter name="aReferrerURI"/>
-        <parameter name="aCharset"/>
-        <parameter name="aPostData"/>
-        <body>
-          <![CDATA[
-            // Note - the callee understands both:
-            // (a) loadURIWithFlags(aURI, aFlags, ...)
-            // (b) loadURIWithFlags(aURI, { flags: aFlags, ... })
-            // Forwarding it as (a) here actually supports both (a) and (b),
-            // so you can call us either way too.
-            return this.mCurrentBrowser.loadURIWithFlags(aURI, aFlags, aReferrerURI, aCharset, aPostData);
-          ]]>
-        </body>
-      </method>
-
-      <method name="goHome">
-        <body>
-          <![CDATA[
-            return this.mCurrentBrowser.goHome();
-          ]]>
-        </body>
-      </method>
-
-      <property name="homePage">
-        <getter>
-          <![CDATA[
-            return this.mCurrentBrowser.homePage;
-          ]]>
-        </getter>
-        <setter>
-          <![CDATA[
-            this.mCurrentBrowser.homePage = val;
-            return val;
-          ]]>
-        </setter>
-      </property>
-
-      <method name="gotoIndex">
-        <parameter name="aIndex"/>
-        <body>
-          <![CDATA[
-            return this.mCurrentBrowser.gotoIndex(aIndex);
-          ]]>
-        </body>
-      </method>
-
-      <method name="attachFormFill">
-        <body><![CDATA[
-          for (var i = 0; i < this.mPanelContainer.childNodes.length; ++i) {
-            var cb = this.getBrowserAtIndex(i);
-            cb.attachFormFill();
-          }
-        ]]></body>
-      </method>
-
-      <method name="detachFormFill">
-        <body><![CDATA[
-          for (var i = 0; i < this.mPanelContainer.childNodes.length; ++i) {
-            var cb = this.getBrowserAtIndex(i);
-            cb.detachFormFill();
-          }
-        ]]></body>
-      </method>
-
-      <property name="currentURI"
-                onget="return this.mCurrentBrowser.currentURI;"
-                readonly="true"/>
-
-      <field name="_fastFind">null</field>
-      <property name="fastFind"
-                readonly="true">
-        <getter>
-        <![CDATA[
-          if (!this._fastFind) {
-            this._fastFind = Components.classes["@mozilla.org/typeaheadfind;1"]
-                                       .createInstance(Components.interfaces.nsITypeAheadFind);
-            this._fastFind.init(this.docShell);
-          }
-          return this._fastFind;
-        ]]>
-        </getter>
-      </property>
-
-      <field name="_lastSearchString">null</field>
-      <field name="_lastSearchHighlight">false</field>
-
-      <field name="finder"><![CDATA[
-        ({
-          mTabBrowser: this,
-          mListeners: new Set(),
-          get finder() {
-            return this.mTabBrowser.mCurrentBrowser.finder;
-          },
-          destroy: function() {
-            this.finder.destroy();
-          },
-          addResultListener: function(aListener) {
-            this.mListeners.add(aListener);
-            this.finder.addResultListener(aListener);
-          },
-          removeResultListener: function(aListener) {
-            this.mListeners.delete(aListener);
-            this.finder.removeResultListener(aListener);
-          },
-          get searchString() {
-            return this.finder.searchString;
-          },
-          get clipboardSearchString() {
-            return this.finder.clipboardSearchString;
-          },
-          set clipboardSearchString(val) {
-            return this.finder.clipboardSearchString = val;
-          },
-          set caseSensitive(val) {
-            return this.finder.caseSensitive = val;
-          },
-          set entireWord(val) {
-            return this.finder.entireWord = val;
-          },
-          get highlighter() {
-            return this.finder.highlighter;
-          },
-          get matchesCountLimit() {
-            return this.finder.matchesCountLimit;
-          },
-          fastFind: function(...args) {
-            this.finder.fastFind(...args);
-          },
-          findAgain: function(...args) {
-            this.finder.findAgain(...args);
-          },
-          setSearchStringToSelection: function() {
-            return this.finder.setSearchStringToSelection();
-          },
-          highlight: function(...args) {
-            this.finder.highlight(...args);
-          },
-          getInitialSelection: function() {
-            this.finder.getInitialSelection();
-          },
-          getActiveSelectionText: function() {
-            return this.finder.getActiveSelectionText();
-          },
-          enableSelection: function() {
-            this.finder.enableSelection();
-          },
-          removeSelection: function() {
-            this.finder.removeSelection();
-          },
-          focusContent: function() {
-            this.finder.focusContent();
-          },
-          onFindbarClose: function() {
-            this.finder.onFindbarClose();
-          },
-          onFindbarOpen: function() {
-            this.finder.onFindbarOpen();
-          },
-          onModalHighlightChange: function(...args) {
-            return this.finder.onModalHighlightChange(...args);
-          },
-          onHighlightAllChange: function(...args) {
-            return this.finder.onHighlightAllChange(...args);
-          },
-          keyPress: function(aEvent) {
-            this.finder.keyPress(aEvent);
-          },
-          requestMatchesCount: function(...args) {
-            this.finder.requestMatchesCount(...args);
-          },
-          onIteratorRangeFound: function(...args) {
-            this.finder.onIteratorRangeFound(...args);
-          },
-          onIteratorReset: function() {
-            this.finder.onIteratorReset();
-          },
-          onIteratorRestart: function(...args) {
-            this.finder.onIteratorRestart(...args);
-          },
-          onIteratorStart: function(...args) {
-            this.finder.onIteratorStart(...args);
-          },
-          onLocationChange: function(...args) {
-            this.finder.onLocationChange(...args);
-          }
-        })
-      ]]></field>
-
-      <property name="docShell"
-                onget="return this.mCurrentBrowser.docShell"
-                readonly="true"/>
-
-      <property name="webNavigation"
-                onget="return this.mCurrentBrowser.webNavigation"
-                readonly="true"/>
-
-      <property name="webBrowserFind"
-                readonly="true"
-                onget="return this.mCurrentBrowser.webBrowserFind"/>
-
-      <property name="webProgress"
-                readonly="true"
-                onget="return this.mCurrentBrowser.webProgress"/>
-
-      <property name="contentWindow"
-                readonly="true"
-                onget="return this.mCurrentBrowser.contentWindow"/>
-
-      <property name="contentWindowAsCPOW"
-                readonly="true"
-                onget="return this.mCurrentBrowser.contentWindow;"/>
-
-      <property name="sessionHistory"
-                onget="return this.mCurrentBrowser.sessionHistory;"
-                readonly="true"/>
-
-      <property name="markupDocumentViewer"
-                onget="return this.mCurrentBrowser.markupDocumentViewer;"
-                readonly="true"/>
-
-      <property name="contentViewerEdit"
-                onget="return this.mCurrentBrowser.contentViewerEdit;"
-                readonly="true"/>
-
-      <property name="contentViewerFile"
-                onget="return this.mCurrentBrowser.contentViewerFile;"
-                readonly="true"/>
-
-      <property name="contentDocument"
-                onget="return this.mCurrentBrowser.contentDocument;"
-                readonly="true"/>
-
-      <property name="contentDocumentAsCPOW"
-                onget="return this.mCurrentBrowser.contentDocument;"
-                readonly="true"/>
-
-      <property name="contentTitle"
-                onget="return this.mCurrentBrowser.contentTitle;"
-                readonly="true"/>
-
-      <property name="contentPrincipal"
-                onget="return this.mCurrentBrowser.contentPrincipal;"
-                readonly="true"/>
-
-      <property name="securityUI"
-                onget="return this.mCurrentBrowser.securityUI;"
-                readonly="true"/>
-
-      <property name="fullZoom"
-                onget="return this.mCurrentBrowser.fullZoom;"
-                onset="this.mCurrentBrowser.fullZoom = val;"/>
-
-      <property name="textZoom"
-                onget="return this.mCurrentBrowser.textZoom;"
-                onset="this.mCurrentBrowser.textZoom = val;"/>
-
-      <property name="isSyntheticDocument"
-                onget="return this.mCurrentBrowser.isSyntheticDocument;"
-                readonly="true"/>
-
-      <method name="_handleKeyEvent">
-        <parameter name="aEvent"/>
-        <body><![CDATA[
-          if (!aEvent.isTrusted) {
-            // Don't let untrusted events mess with tabs.
-            return;
-          }
-
-          if (aEvent.altKey)
-            return;
-
-          if (aEvent.ctrlKey && aEvent.shiftKey && !aEvent.metaKey) {
-            switch (aEvent.keyCode) {
-              case aEvent.DOM_VK_PAGE_UP:
-                this.moveTabBackward();
-                aEvent.stopPropagation();
-                aEvent.preventDefault();
-                return;
-              case aEvent.DOM_VK_PAGE_DOWN:
-                this.moveTabForward();
-                aEvent.stopPropagation();
-                aEvent.preventDefault();
-                return;
-            }
-          }
-
-#ifdef XP_MACOSX
-          if (!aEvent.metaKey)
-            return;
-
-          var offset = 1;
-          switch (aEvent.charCode) {
-            case '}'.charCodeAt(0):
-              offset = -1;
-            case '{'.charCodeAt(0):
-              if (window.getComputedStyle(this, null).direction == "ltr")
-                offset *= -1;
-              this.tabContainer.advanceSelectedTab(offset, true);
-              aEvent.stopPropagation();
-              aEvent.preventDefault();
-          }
-#else
-          if (aEvent.ctrlKey && !aEvent.shiftKey && !aEvent.metaKey &&
-              aEvent.keyCode == KeyEvent.DOM_VK_F4 &&
-              !this.mCurrentTab.pinned) {
-            this.removeCurrentTab({animate: true});
-            aEvent.stopPropagation();
-            aEvent.preventDefault();
-          }
-#endif
-        ]]></body>
-      </method>
-
-      <property name="userTypedValue"
-                onget="return this.mCurrentBrowser.userTypedValue;"
-                onset="return this.mCurrentBrowser.userTypedValue = val;"/>
-
-      <method name="createTooltip">
-        <parameter name="event"/>
-        <body><![CDATA[
-          event.stopPropagation();
-          var tab = document.tooltipNode;
-          if (tab.localName != "tab") {
-            event.preventDefault();
-            return;
-          }
-
-          var stringID, label;
-          if (tab.mOverCloseButton) {
-            stringID = "tabs.closeTab";
-          } else if (tab._overPlayingIcon) {
-            if (tab.linkedBrowser.audioBlocked) {
-              stringID = "tabs.unblockAudio.tooltip";
-            } else {
-              stringID = tab.linkedBrowser.audioMuted ?
-                "tabs.unmuteAudio.tooltip" :
-                "tabs.muteAudio.tooltip";
-            }
-          } else {
-            label = tab.getAttribute("label");
-          }
-          if (stringID && !label) {
-            label = this.mStringBundle.getString(stringID);
-          }
-          event.target.setAttribute("label", label);
-        ]]></body>
-      </method>
-
-      <method name="handleEvent">
-        <parameter name="aEvent"/>
-        <body><![CDATA[
-          switch (aEvent.type) {
-            case "keypress":
-              this._handleKeyEvent(aEvent);
-              break;
-            case "sizemodechange":
-              if (aEvent.target == window) {
-                this.mCurrentBrowser.docShellIsActive =
-                  (window.windowState != window.STATE_MINIMIZED);
-              }
-              break;
-          }
-        ]]></body>
-      </method>
-
-      <method name="receiveMessage">
-        <parameter name="aMessage"/>
-        <body><![CDATA[
-          let json = aMessage.json;
-          let browser = aMessage.target;
-
-          switch (aMessage.name) {
-            case "DOMTitleChanged": {
-              let tab = this.getTabForBrowser(browser);
-              if (!tab)
-                return;
-              let titleChanged = this.setTabTitle(tab);
-              if (titleChanged && !tab.selected && !tab.hasAttribute("busy"))
-                tab.setAttribute("titlechanged", "true");
-              break;
-            }
-            case "DOMWebNotificationClicked": {
-              let tab = this.getTabForBrowser(browser);
-              if (!tab)
-                return;
-              this.selectedTab = tab;
-              window.focus();
-              break;
-            }
-          }
-        ]]></body>
-      </method>
-
-      <constructor>
-        <![CDATA[
-          let browserStack = document.getAnonymousElementByAttribute(this, "anonid", "browserStack");
-          this.mCurrentBrowser = document.getAnonymousElementByAttribute(this, "anonid", "initialBrowser");
-          if (Services.prefs.getBoolPref("browser.tabs.remote")) {
-            browserStack.removeChild(this.mCurrentBrowser);
-            this.mCurrentBrowser.setAttribute("remote", true);
-            browserStack.appendChild(this.mCurrentBrowser);
-          }
-
-          this.mCurrentTab = this.tabContainer.firstChild;
-          document.addEventListener("keypress", this, false);
-          window.addEventListener("sizemodechange", this, false);
-
-          var uniqueId = "panel" + Date.now();
-          this.mPanelContainer.childNodes[0].id = uniqueId;
-          this.mCurrentTab.linkedPanel = uniqueId;
-          this.mCurrentTab._tPos = 0;
-          this.mCurrentTab._fullyOpen = true;
-          this.mCurrentTab.linkedBrowser = this.mCurrentBrowser;
-          this._tabForBrowser.set(this.mCurrentBrowser, this.mCurrentTab);
-
-          // set up the shared autoscroll popup
-          this._autoScrollPopup = this.mCurrentBrowser._createAutoScrollPopup();
-          this._autoScrollPopup.id = "autoscroller";
-          this.appendChild(this._autoScrollPopup);
-          this.mCurrentBrowser.setAttribute("autoscrollpopup", this._autoScrollPopup.id);
-          this.mCurrentBrowser.droppedLinkHandler = handleDroppedLink;
-          this.updateWindowResizers();
-
-          // Hook up the event listeners to the first browser
-          var tabListener = this.mTabProgressListener(this.mCurrentTab, this.mCurrentBrowser, true);
-          const nsIWebProgress = Components.interfaces.nsIWebProgress;
-          const filter = Components.classes["@mozilla.org/appshell/component/browser-status-filter;1"]
-                                   .createInstance(nsIWebProgress);
-          filter.addProgressListener(tabListener, nsIWebProgress.NOTIFY_ALL);
-          this.mTabListeners[0] = tabListener;
-          this.mTabFilters[0] = filter;
-
-          try {
-            // We assume this can only fail because mCurrentBrowser's docShell
-            // hasn't been created, yet. This may be caused by code accessing
-            // gBrowser before the window has finished loading.
-            this._addProgressListenerForInitialTab();
-          } catch (e) {
-            // The binding was constructed too early, wait until the initial
-            // tab's document is ready, then add the progress listener.
-            this._waitForInitialContentDocument();
-          }
-
-          this.style.backgroundColor =
-            Services.prefs.getBoolPref("browser.display.use_system_colors") ?
-              "-moz-default-background-color" :
-              Services.prefs.getCharPref("browser.display.background_color");
-
-          if (Services.prefs.getBoolPref("browser.tabs.remote")) {
-            messageManager.addMessageListener("DOMTitleChanged", this);
-          } else {
-            this._outerWindowIDBrowserMap.set(this.mCurrentBrowser.outerWindowID,
-                                              this.mCurrentBrowser);
-          }
-          messageManager.addMessageListener("DOMWebNotificationClicked", this);
-        ]]>
-      </constructor>
-
-      <method name="_addProgressListenerForInitialTab">
-        <body><![CDATA[
-          this.webProgress.addProgressListener(this.mTabFilters[0], Ci.nsIWebProgress.NOTIFY_ALL);
-        ]]></body>
-      </method>
-
-      <method name="_waitForInitialContentDocument">
-        <body><![CDATA[
-          let obs = (subject, topic) => {
-            if (this.browsers[0].contentWindow == subject) {
-              Services.obs.removeObserver(obs, topic);
-              this._addProgressListenerForInitialTab();
-            }
-          };
-
-          // We use content-document-global-created as an approximation for
-          // "docShell is initialized". We can do this because in the
-          // mTabProgressListener we care most about the STATE_STOP notification
-          // that will reset mBlank. That means it's important to at least add
-          // the progress listener before the initial about:blank load stops
-          // if we can't do it before the load starts.
-          Services.obs.addObserver(obs, "content-document-global-created", false);
-        ]]></body>
-      </method>
-
-      <destructor>
-        <![CDATA[
-          for (var i = 0; i < this.mTabListeners.length; ++i) {
-            let browser = this.getBrowserAtIndex(i);
-            if (browser.registeredOpenURI) {
-              this._placesAutocomplete.unregisterOpenPage(browser.registeredOpenURI);
-              delete browser.registeredOpenURI;
-            }
-            browser.webProgress.removeProgressListener(this.mTabFilters[i]);
-            this.mTabFilters[i].removeProgressListener(this.mTabListeners[i]);
-            this.mTabFilters[i] = null;
-            this.mTabListeners[i].destroy();
-            this.mTabListeners[i] = null;
-          }
-          document.removeEventListener("keypress", this, false);
-          window.removeEventListener("sizemodechange", this, false);
-
-          if (Services.prefs.getBoolPref("browser.tabs.remote"))
-            messageManager.removeMessageListener("DOMTitleChanged", this);
-        ]]>
-      </destructor>
-
-      <!-- Deprecated stuff, implemented for backwards compatibility. -->
-      <method name="enterTabbedMode">
-        <body>
-          Application.console.log("enterTabbedMode is an obsolete method and " +
-                                  "will be removed in a future release.");
-        </body>
-      </method>
-      <field name="mTabbedMode" readonly="true">true</field>
-      <method name="setStripVisibilityTo">
-        <parameter name="aShow"/>
-        <body>
-          this.tabContainer.visible = aShow;
-        </body>
-      </method>
-      <method name="getStripVisibility">
-        <body>
-          return this.tabContainer.visible;
-        </body>
-      </method>
-      <property name="mContextTab" readonly="true"
-                onget="return TabContextMenu.contextTab;"/>
-      <property name="mPrefs" readonly="true"
-                onget="return Services.prefs;"/>
-      <property name="mTabContainer" readonly="true"
-                onget="return this.tabContainer;"/>
-      <property name="mTabs" readonly="true"
-                onget="return this.tabs;"/>
-      <!--
-        - Compatibility hack: several extensions depend on this property to
-        - access the tab context menu or tab container, so keep that working for
-        - now. Ideally we can remove this once extensions are using
-        - tabbrowser.tabContextMenu and tabbrowser.tabContainer directly.
-        -->
-      <property name="mStrip" readonly="true">
-        <getter>
-        <![CDATA[
-          return ({
-            self: this,
-            childNodes: [null, this.tabContextMenu, this.tabContainer],
-            firstChild: { nextSibling: this.tabContextMenu },
-            getElementsByAttribute: function (attr, attrValue) {
-              if (attr == "anonid" && attrValue == "tabContextMenu")
-                return [this.self.tabContextMenu];
-              return [];
-            },
-            // Also support adding event listeners (forward to the tab container)
-            addEventListener: function (a,b,c) { this.self.tabContainer.addEventListener(a,b,c); },
-            removeEventListener: function (a,b,c) { this.self.tabContainer.removeEventListener(a,b,c); }
-          });
-        ]]>
-        </getter>
-      </property>
-      <field name="_soundPlayingAttrRemovalTimer">0</field>
-    </implementation>
-
-    <handlers>
-      <handler event="DOMWindowClose" phase="capturing">
-        <![CDATA[
-          if (!event.isTrusted)
-            return;
-
-          if (this.tabs.length == 1)
-            return;
-
-          var tab = this._getTabForContentWindow(event.target);
-          if (tab) {
-            this.removeTab(tab);
-            event.preventDefault();
-          }
-        ]]>
-      </handler>
-      <handler event="DOMWillOpenModalDialog" phase="capturing">
-        <![CDATA[
-          if (!event.isTrusted)
-            return;
-
-          // We're about to open a modal dialog, make sure the opening
-          // tab is brought to the front.
-          this.selectedTab = this._getTabForContentWindow(event.target.top);
-        ]]>
-      </handler>
-      <handler event="DOMTitleChanged">
-        <![CDATA[
-          if (!event.isTrusted)
-            return;
-
-          var contentWin = event.target.defaultView;
-          if (contentWin != contentWin.top)
-            return;
-
-          var tab = this._getTabForContentWindow(contentWin);
-          if (!tab) {
-            return;
-          }
-
-          var titleChanged = this.setTabTitle(tab);
-          if (titleChanged && !tab.selected && !tab.hasAttribute("busy"))
-            tab.setAttribute("titlechanged", "true");
-        ]]>
-      </handler>
-      <handler event="DOMAudioPlaybackStarted">
-        <![CDATA[
-          var tab = getTabFromAudioEvent(event)
-          if (!tab) {
-            return;
-          }
-
-          clearTimeout(tab._soundPlayingAttrRemovalTimer);
-          tab._soundPlayingAttrRemovalTimer = 0;
-
-          let modifiedAttrs = [];
-          if (tab.hasAttribute("soundplaying-scheduledremoval")) {
-            tab.removeAttribute("soundplaying-scheduledremoval");
-            modifiedAttrs.push("soundplaying-scheduledremoval");
-          }
-
-          if (!tab.hasAttribute("soundplaying")) {
-            tab.setAttribute("soundplaying", true);
-            modifiedAttrs.push("soundplaying");
-          }
-
-          this._tabAttrModified(tab, modifiedAttrs);
-        ]]>
-      </handler>
-      <handler event="DOMAudioPlaybackStopped">
-        <![CDATA[
-          var tab = getTabFromAudioEvent(event)
-          if (!tab) {
-            return;
-          }
-
-          if (tab.hasAttribute("soundplaying")) {
-            let removalDelay = Services.prefs.getIntPref("browser.tabs.delayHidingAudioPlayingIconMS");
-
-            tab.style.setProperty("--soundplaying-removal-delay", `${removalDelay - 300}ms`);
-            tab.setAttribute("soundplaying-scheduledremoval", "true");
-            this._tabAttrModified(tab, ["soundplaying-scheduledremoval"]);
-
-            tab._soundPlayingAttrRemovalTimer = setTimeout(() => {
-              tab.removeAttribute("soundplaying-scheduledremoval");
-              tab.removeAttribute("soundplaying");
-              this._tabAttrModified(tab, ["soundplaying", "soundplaying-scheduledremoval"]);
-            }, removalDelay);
-          }
-        ]]>
-      </handler>
-      <handler event="DOMAudioPlaybackBlockStarted">
-        <![CDATA[
-          var tab = getTabFromAudioEvent(event)
-          if (!tab) {
-            return;
-          }
-
-          if (!tab.hasAttribute("blocked")) {
-            tab.setAttribute("blocked", true);
-            this._tabAttrModified(tab, ["blocked"]);
-          }
-        ]]>
-      </handler>
-      <handler event="DOMAudioPlaybackBlockStopped">
-        <![CDATA[
-          var tab = getTabFromAudioEvent(event)
-          if (!tab) {
-            return;
-          }
-
-          if (tab.hasAttribute("blocked")) {
-            tab.removeAttribute("blocked");
-            this._tabAttrModified(tab, ["blocked"]);
-          }
-        ]]>
-      </handler>
-    </handlers>
-  </binding>
-
-  <binding id="tabbrowser-tabbox"
-           extends="chrome://global/content/bindings/tabbox.xml#tabbox">
-    <implementation>
-      <property name="tabs" readonly="true"
-                onget="return document.getBindingParent(this).tabContainer;"/>
-    </implementation>
-  </binding>
-
-  <binding id="tabbrowser-arrowscrollbox" extends="chrome://global/content/bindings/scrollbox.xml#arrowscrollbox-clicktoscroll">
-    <implementation>
-      <!-- Override scrollbox.xml method, since our scrollbox's children are
-           inherited from the binding parent -->
-      <method name="_getScrollableElements">
-        <body><![CDATA[
-          return Array.filter(document.getBindingParent(this).childNodes,
-                              this._canScrollToElement, this);
-        ]]></body>
-      </method>
-      <method name="_canScrollToElement">
-        <parameter name="tab"/>
-        <body><![CDATA[
-          return !tab.pinned && !tab.hidden;
-        ]]></body>
-      </method>
-    </implementation>
-
-    <handlers>
-      <handler event="underflow" phase="capturing"><![CDATA[
-        if (event.detail == 0)
-          return; // Ignore vertical events
-
-        var tabs = document.getBindingParent(this);
-        tabs.removeAttribute("overflow");
-
-        if (tabs._lastTabClosedByMouse)
-          tabs._expandSpacerBy(this._scrollButtonDown.clientWidth);
-
-        tabs.tabbrowser._removingTabs.forEach(tabs.tabbrowser.removeTab,
-                                              tabs.tabbrowser);
-
-        tabs._positionPinnedTabs();
-      ]]></handler>
-      <handler event="overflow"><![CDATA[
-        if (event.detail == 0)
-          return; // Ignore vertical events
-
-        var tabs = document.getBindingParent(this);
-        tabs.setAttribute("overflow", "true");
-        tabs._positionPinnedTabs();
-        tabs._handleTabSelect(false);
-      ]]></handler>
-    </handlers>
-  </binding>
-
-  <binding id="tabbrowser-tabs"
-           extends="chrome://global/content/bindings/tabbox.xml#tabs">
-    <resources>
-      <stylesheet src="chrome://browser/content/tabbrowser.css"/>
-    </resources>
-
-    <content>
-      <xul:hbox align="end">
-        <xul:image class="tab-drop-indicator" anonid="tab-drop-indicator" collapsed="true"/>
-      </xul:hbox>
-      <xul:arrowscrollbox anonid="arrowscrollbox" orient="horizontal" flex="1"
-                          style="min-width: 1px;"
-#ifndef XP_MACOSX
-                          clicktoscroll="true"
-#endif
-                          class="tabbrowser-arrowscrollbox">
-# This is a hack to circumvent bug 472020, otherwise the tabs show up on the
-# right of the newtab button.
-        <children includes="tab"/>
-# This is to ensure anything extensions put here will go before the newtab
-# button, necessary due to the previous hack.
-        <children/>
-        <xul:toolbarbutton class="tabs-newtab-button"
-                           command="cmd_newNavigatorTab"
-                           onclick="checkForMiddleClick(this, event);"
-                           onmouseover="document.getBindingParent(this)._enterNewTab();"
-                           onmouseout="document.getBindingParent(this)._leaveNewTab();"
-                           tooltiptext="&newTabButton.tooltip;"/>
-        <xul:spacer class="closing-tabs-spacer" anonid="closing-tabs-spacer"
-                    style="width: 0;"/>
-      </xul:arrowscrollbox>
-    </content>
-
-    <implementation implements="nsIDOMEventListener">
-      <constructor>
-        <![CDATA[
-          this.mTabClipWidth = Services.prefs.getIntPref("browser.tabs.tabClipWidth");
-          this.mCloseButtons = Services.prefs.getIntPref("browser.tabs.closeButtons");
-          this._closeWindowWithLastTab = Services.prefs.getBoolPref("browser.tabs.closeWindowWithLastTab");
-
-          var tab = this.firstChild;
-          tab.setAttribute("label",
-                           this.tabbrowser.mStringBundle.getString("tabs.emptyTabTitle"));
-          tab.setAttribute("crop", "end");
-          tab.setAttribute("onerror", "this.removeAttribute('image');");
-          this.adjustTabstrip();
-
-          Services.prefs.addObserver("browser.tabs.", this._prefObserver, false);
-          window.addEventListener("resize", this, false);
-          window.addEventListener("load", this, false);
-
-          this._tabAnimationLoggingEnabled = Services.prefs.getBoolPref("browser.tabs.animationLogging.enabled", false);
-          this._browserNewtabpageEnabled = Services.prefs.getBoolPref("browser.newtabpage.enabled");
-        ]]>
-      </constructor>
-
-      <destructor>
-        <![CDATA[
-          Services.prefs.removeObserver("browser.tabs.", this._prefObserver);
-        ]]>
-      </destructor>
-
-      <field name="tabbrowser" readonly="true">
-        document.getElementById(this.getAttribute("tabbrowser"));
-      </field>
-
-      <field name="tabbox" readonly="true">
-        this.tabbrowser.mTabBox;
-      </field>
-
-      <field name="contextMenu" readonly="true">
-        document.getElementById("tabContextMenu");
-      </field>
-
-      <field name="mTabstripWidth">0</field>
-
-      <field name="mTabstrip">
-        document.getAnonymousElementByAttribute(this, "anonid", "arrowscrollbox");
-      </field>
-
-      <field name="_firstTab">null</field>
-      <field name="_lastTab">null</field>
-      <field name="_afterSelectedTab">null</field>
-      <field name="_beforeHoveredTab">null</field>
-      <field name="_afterHoveredTab">null</field>
-
-      <method name="_setPositionalAttributes">
-        <body><![CDATA[
-          let visibleTabs = this.tabbrowser.visibleTabs;
-
-          if (!visibleTabs.length)
-            return;
-
-          let selectedIndex = visibleTabs.indexOf(this.selectedItem);
-
-          let lastVisible = visibleTabs.length - 1;
-
-          if (this._afterSelectedTab)
-            this._afterSelectedTab.removeAttribute("afterselected-visible");
-          if (this.selectedItem.closing || selectedIndex == lastVisible) {
-            this._afterSelectedTab = null;
-          } else {
-            this._afterSelectedTab = visibleTabs[selectedIndex + 1];
-            this._afterSelectedTab.setAttribute("afterselected-visible",
-                                                "true");
-          }
-
-          if (this._firstTab)
-            this._firstTab.removeAttribute("first-visible-tab");
-          this._firstTab = visibleTabs[0];
-          this._firstTab.setAttribute("first-visible-tab", "true");
-          if (this._lastTab)
-            this._lastTab.removeAttribute("last-visible-tab");
-          this._lastTab = visibleTabs[lastVisible];
-          this._lastTab.setAttribute("last-visible-tab", "true");
-        ]]></body>
-      </method>
-
-      <field name="_prefObserver"><![CDATA[({
-        tabContainer: this,
-
-        observe: function (subject, topic, data) {
-          switch (data) {
-            case "browser.tabs.closeButtons":
-              this.tabContainer.mCloseButtons = Services.prefs.getIntPref(data);
-              this.tabContainer.adjustTabstrip();
-              break;
-            case "browser.tabs.autoHide":
-              this.tabContainer.updateVisibility();
-              break;
-            case "browser.tabs.closeWindowWithLastTab":
-              this.tabContainer._closeWindowWithLastTab = Services.prefs.getBoolPref(data);
-              this.tabContainer.adjustTabstrip();
-              break;
-          }
-        }
-      });]]></field>
-      <field name="_blockDblClick">false</field>
-
-      <field name="_tabDropIndicator">
-        document.getAnonymousElementByAttribute(this, "anonid", "tab-drop-indicator");
-      </field>
-
-      <field name="_dragOverDelay">350</field>
-      <field name="_dragTime">0</field>
-
-      <field name="_container" readonly="true"><![CDATA[
-        this.parentNode && this.parentNode.localName == "toolbar" ? this.parentNode : this;
-      ]]></field>
-
-      <field name="_propagatedVisibilityOnce">false</field>
-
-      <property name="visible"
-                onget="return !this._container.collapsed;">
-        <setter><![CDATA[
-          if (val == this.visible &&
-              this._propagatedVisibilityOnce)
-            return val;
-
-          this._container.collapsed = !val;
-
-          this._propagateVisibility();
-          this._propagatedVisibilityOnce = true;
-
-          return val;
-        ]]></setter>
-      </property>
-
-      <method name="_enterNewTab">
-        <body><![CDATA[
-          let visibleTabs = this.tabbrowser.visibleTabs;
-          let candidate = visibleTabs[visibleTabs.length - 1];
-          if (!candidate.selected) {
-            this._beforeHoveredTab = candidate;
-            candidate.setAttribute("beforehovered", "true");
-          }
-        ]]></body>
-      </method>
-
-      <method name="_leaveNewTab">
-        <body><![CDATA[
-          if (this._beforeHoveredTab) {
-            this._beforeHoveredTab.removeAttribute("beforehovered");
-            this._beforeHoveredTab = null;
-          }
-        ]]></body>
-      </method>
-
-      <method name="_propagateVisibility">
-        <body><![CDATA[
-          let visible = this.visible;
-
-          document.getElementById("menu_closeWindow").hidden = !visible;
-          document.getElementById("menu_close").setAttribute("label",
-            this.tabbrowser.mStringBundle.getString(visible ? "tabs.closeTab" : "tabs.close"));
-
-          goSetCommandEnabled("cmd_ToggleTabsOnTop", visible);
-
-          TabsOnTop.syncUI();
-
-          TabsInTitlebar.allowedBy("tabs-visible", visible);
-        ]]></body>
-      </method>
-
-      <method name="updateVisibility">
-        <body><![CDATA[
-          if (this.childNodes.length - this.tabbrowser._removingTabs.length == 1)
-            this.visible = window.toolbar.visible &&
-            !Services.prefs.getBoolPref("browser.tabs.autoHide");
-          else
-            this.visible = true;
-        ]]></body>
-      </method>
-
-      <method name="adjustTabstrip">
-        <body><![CDATA[
-          let numTabs = this.childNodes.length -
-                        this.tabbrowser._removingTabs.length;
-          // modes for tabstrip
-          // 0 - button on active tab only
-          // 1 - close buttons on all tabs, if available space allows
-          // 2 - no close buttons at all
-          // 3 - close button at the end of the tabstrip
-          switch (this.mCloseButtons) {
-          case 0:
-            // If we decide we want to hide the close tab button on the last tab
-            // when closing the window with the last tab, then we should check
-            // if (numTabs == 1 && this._closeWindowWithLastTab) here and set
-            // this.setAttribute("closebuttons", "hidden") appropriately
-            this.setAttribute("closebuttons", "activetab");
-            break;
-          case 1:
-            if (numTabs == 1) {
-              // See remark about potentially hiding the close tab button, above.
-              this.setAttribute("closebuttons", "alltabs");
-            } else if (numTabs == 2) {
-              // This is an optimization to avoid layout flushes by calling
-              // getBoundingClientRect() when we just opened a second tab. In
-              // this case it's highly unlikely that the tab width is smaller
-              // than mTabClipWidth and the tab close button obscures too much
-              // of the tab's label. In the edge case of the window being too
-              // narrow (or if tabClipWidth has been set to a way higher value),
-              // we'll correct the 'closebuttons' attribute after the tabopen
-              // animation has finished.
-              this.setAttribute("closebuttons", "alltabs");
-            } else {
-              let tab = this.tabbrowser.visibleTabs[this.tabbrowser._numPinnedTabs];
-              if (tab && tab.getBoundingClientRect().width > this.mTabClipWidth)
-                this.setAttribute("closebuttons", "alltabs");
-              else
-                this.setAttribute("closebuttons", "activetab");
-            }
-            break;
-          case 2:
-          case 3:
-            this.setAttribute("closebuttons", "never");
-            break;
-          }
-          var tabstripClosebutton = document.getElementById("tabs-closebutton");
-          if (tabstripClosebutton && tabstripClosebutton.parentNode == this._container)
-            tabstripClosebutton.collapsed = this.mCloseButtons != 3;
-        ]]></body>
-      </method>
-
-      <method name="_handleTabSelect">
-        <parameter name="aSmoothScroll"/>
-        <body><![CDATA[
-          if (this.getAttribute("overflow") == "true")
-            this.mTabstrip.ensureElementIsVisible(this.selectedItem, aSmoothScroll);
-        ]]></body>
-      </method>
-
-      <method name="_fillTrailingGap">
-        <body><![CDATA[
-          try {
-            // if we're at the right side (and not the logical end,
-            // which is why this works for both LTR and RTL)
-            // of the tabstrip, we need to ensure that we stay
-            // completely scrolled to the right side
-            var tabStrip = this.mTabstrip;
-            if (tabStrip.scrollPosition + tabStrip.scrollClientSize >
-                tabStrip.scrollSize)
-              tabStrip.scrollByPixels(-1);
-          } catch (e) {}
-        ]]></body>
-      </method>
-
-      <field name="_closingTabsSpacer">
-        document.getAnonymousElementByAttribute(this, "anonid", "closing-tabs-spacer");
-      </field>
-
-      <field name="_tabDefaultMaxWidth">NaN</field>
-      <field name="_lastTabClosedByMouse">false</field>
-      <field name="_hasTabTempMaxWidth">false</field>
-
-      <!-- Try to keep the active tab's close button under the mouse cursor -->
-      <method name="_lockTabSizing">
-        <parameter name="aTab"/>
-        <body><![CDATA[
-          var tabs = this.tabbrowser.visibleTabs;
-          if (!tabs.length)
-            return;
-
-          var isEndTab = (aTab._tPos > tabs[tabs.length-1]._tPos);
-          var tabWidth = aTab.getBoundingClientRect().width;
-
-          if (!this._tabDefaultMaxWidth)
-            this._tabDefaultMaxWidth =
-              parseFloat(window.getComputedStyle(aTab).maxWidth);
-          this._lastTabClosedByMouse = true;
-
-          if (this.getAttribute("overflow") == "true") {
-#ifdef XP_WIN
-            // Don't need to do anything if we're in overflow mode and we're closing
-            // the last tab.
-            if (isEndTab)
-#else
-            // Don't need to do anything if we're in overflow mode and aren't scrolled
-            // all the way to the right, or if we're closing the last tab.
-            if (isEndTab || !this.mTabstrip._scrollButtonDown.disabled)
-#endif
-              return;
-
-            // If the tab has an owner that will become the active tab, the owner will
-            // be to the left of it, so we actually want the left tab to slide over.
-            // This can't be done as easily in non-overflow mode, so we don't bother.
-            if (aTab.owner)
-              return;
-
-            // Resize immediately if preffed
-            // XXX: we may want to make this a three-state pref to disable this early
-            // exit if people prefer a mix of behavior (don't resize in overflow,
-            // but resize if not overflowing)
-            if (Services.prefs.getBoolPref("browser.tabs.resize_immediately"))
-              return;
-
-            this._expandSpacerBy(tabWidth);
-          } else { // non-overflow mode
-            // Locking is neither in effect nor needed, so let tabs expand normally.
-            if (isEndTab && !this._hasTabTempMaxWidth)
-              return;
-              
-            // Resize immediately if preffed
-            // XXX: we may want to make this a three-state pref to disable this early
-            // exit if people prefer a mix of behavior (don't resize in overflow,
-            // but resize if not overflowing)
-            if (Services.prefs.getBoolPref("browser.tabs.resize_immediately"))
-              return;
-
-            let numPinned = this.tabbrowser._numPinnedTabs;
-            // Force tabs to stay the same width, unless we're closing the last tab,
-            // which case we need to let them expand just enough so that the overall
-            // tabbar width is the same.
-            if (isEndTab) {
-              let numNormalTabs = tabs.length - numPinned;
-              tabWidth = tabWidth * (numNormalTabs + 1) / numNormalTabs;
-              if (tabWidth > this._tabDefaultMaxWidth)
-                tabWidth = this._tabDefaultMaxWidth;
-            }
-            tabWidth += "px";
-            for (let i = numPinned; i < tabs.length; i++) {
-              let tab = tabs[i];
-              tab.style.setProperty("max-width", tabWidth, "important");
-              if (!isEndTab) { // keep tabs the same width
-                tab.style.transition = "none";
-                tab.clientTop; // flush styles to skip animation; see bug 649247
-                tab.style.transition = "";
-              }
-            }
-            this._hasTabTempMaxWidth = true;
-            this.tabbrowser.addEventListener("mousemove", this, false);
-            window.addEventListener("mouseout", this, false);
-          }
-        ]]></body>
-      </method>
-
-      <method name="_expandSpacerBy">
-        <parameter name="pixels"/>
-        <body><![CDATA[
-          let spacer = this._closingTabsSpacer;
-          spacer.style.width = parseFloat(spacer.style.width) + pixels + "px";
-          this.setAttribute("using-closing-tabs-spacer", "true");
-          this.tabbrowser.addEventListener("mousemove", this, false);
-          window.addEventListener("mouseout", this, false);
-        ]]></body>
-      </method>
-
-      <method name="_unlockTabSizing">
-        <body><![CDATA[
-          this.tabbrowser.removeEventListener("mousemove", this, false);
-          window.removeEventListener("mouseout", this, false);
-
-          if (this._hasTabTempMaxWidth) {
-            this._hasTabTempMaxWidth = false;
-            let tabs = this.tabbrowser.visibleTabs;
-            for (let i = 0; i < tabs.length; i++)
-              tabs[i].style.maxWidth = "";
-          }
-
-          if (this.hasAttribute("using-closing-tabs-spacer")) {
-            this.removeAttribute("using-closing-tabs-spacer");
-            this._closingTabsSpacer.style.width = 0;
-          }
-        ]]></body>
-      </method>
-
-      <field name="_lastNumPinned">0</field>
-      <method name="_positionPinnedTabs">
-        <body><![CDATA[
-          var numPinned = this.tabbrowser._numPinnedTabs;
-          var doPosition = this.getAttribute("overflow") == "true" &&
-                           numPinned > 0;
-
-          if (doPosition) {
-            this.setAttribute("positionpinnedtabs", "true");
-
-            let scrollButtonWidth = this.mTabstrip._scrollButtonDown.getBoundingClientRect().width;
-            let paddingStart = this.mTabstrip.scrollboxPaddingStart;
-            let width = 0;
-
-            for (let i = numPinned - 1; i >= 0; i--) {
-              let tab = this.childNodes[i];
-              width += tab.getBoundingClientRect().width;
-              tab.style.MozMarginStart = - (width + scrollButtonWidth + paddingStart) + "px";
-            }
-
-            this.style.MozPaddingStart = width + paddingStart + "px";
-
-          } else {
-            this.removeAttribute("positionpinnedtabs");
-
-            for (let i = 0; i < numPinned; i++) {
-              let tab = this.childNodes[i];
-              tab.style.MozMarginStart = "";
-            }
-
-            this.style.MozPaddingStart = "";
-          }
-
-          if (this._lastNumPinned != numPinned) {
-            this._lastNumPinned = numPinned;
-            this._handleTabSelect(false);
-          }
-        ]]></body>
-      </method>
-
-      <method name="_animateTabMove">
-        <parameter name="event"/>
-        <body><![CDATA[
-          let draggedTab = event.dataTransfer.mozGetDataAt(TAB_DROP_TYPE, 0);
-
-          if (this.getAttribute("movingtab") != "true") {
-            this.setAttribute("movingtab", "true");
-            this.selectedItem = draggedTab;
-          }
-
-          if (!("animLastScreenX" in draggedTab._dragData))
-            draggedTab._dragData.animLastScreenX = draggedTab._dragData.screenX;
-
-          let screenX = event.screenX;
-          if (screenX == draggedTab._dragData.animLastScreenX)
-            return;
-
-          let draggingRight = screenX > draggedTab._dragData.animLastScreenX;
-          draggedTab._dragData.animLastScreenX = screenX;
-
-          let rtl = (window.getComputedStyle(this).direction == "rtl");
-          let pinned = draggedTab.pinned;
-          let numPinned = this.tabbrowser._numPinnedTabs;
-          let tabs = this.tabbrowser.visibleTabs
-                                    .slice(pinned ? 0 : numPinned,
-                                           pinned ? numPinned : undefined);
-          if (rtl)
-            tabs.reverse();
-          let tabWidth = draggedTab.getBoundingClientRect().width;
-
-          // Move the dragged tab based on the mouse position.
-
-          let leftTab = tabs[0];
-          let rightTab = tabs[tabs.length - 1];
-          let tabScreenX = draggedTab.boxObject.screenX;
-          let translateX = screenX - draggedTab._dragData.screenX;
-          if (!pinned)
-            translateX += this.mTabstrip.scrollPosition - draggedTab._dragData.scrollX;
-          let leftBound = leftTab.boxObject.screenX - tabScreenX;
-          let rightBound = (rightTab.boxObject.screenX + rightTab.boxObject.width) -
-                           (tabScreenX + tabWidth);
-          translateX = Math.max(translateX, leftBound);
-          translateX = Math.min(translateX, rightBound);
-          draggedTab.style.transform = "translateX(" + translateX + "px)";
-
-          // Determine what tab we're dragging over.
-          // * Point of reference is the center of the dragged tab. If that
-          //   point touches a background tab, the dragged tab would take that
-          //   tab's position when dropped.
-          // * We're doing a binary search in order to reduce the amount of
-          //   tabs we need to check.
-
-          let tabCenter = tabScreenX + translateX + tabWidth / 2;
-          let newIndex = -1;
-          let oldIndex = "animDropIndex" in draggedTab._dragData ?
-                         draggedTab._dragData.animDropIndex : draggedTab._tPos;
-          let low = 0;
-          let high = tabs.length - 1;
-          while (low <= high) {
-            let mid = Math.floor((low + high) / 2);
-            if (tabs[mid] == draggedTab &&
-                ++mid > high)
-              break;
-            let boxObject = tabs[mid].boxObject;
-            let screenX = boxObject.screenX + getTabShift(tabs[mid], oldIndex);
-            if (screenX > tabCenter) {
-              high = mid - 1;
-            } else if (screenX + boxObject.width < tabCenter) {
-              low = mid + 1;
-            } else {
-              newIndex = tabs[mid]._tPos;
-              break;
-            }
-          }
-          if (newIndex >= oldIndex)
-            newIndex++;
-          if (newIndex < 0 || newIndex == oldIndex)
-            return;
-          draggedTab._dragData.animDropIndex = newIndex;
-
-          // Shift background tabs to leave a gap where the dragged tab
-          // would currently be dropped.
-
-          for (let tab of tabs) {
-            if (tab != draggedTab) {
-              let shift = getTabShift(tab, newIndex);
-              tab.style.transform = shift ? "translateX(" + shift + "px)" : "";
-            }
-          }
-
-          function getTabShift(tab, dropIndex) {
-            if (tab._tPos < draggedTab._tPos && tab._tPos >= dropIndex)
-              return rtl ? -tabWidth : tabWidth;
-            if (tab._tPos > draggedTab._tPos && tab._tPos < dropIndex)
-              return rtl ? tabWidth : -tabWidth;
-            return 0;
-          }
-        ]]></body>
-      </method>
-
-      <method name="_finishAnimateTabMove">
-        <body><![CDATA[
-          if (this.getAttribute("movingtab") != "true")
-            return;
-
-          for (let tab of this.tabbrowser.visibleTabs)
-            tab.style.transform = "";
-
-          this.removeAttribute("movingtab");
-
-          this._handleTabSelect();
-        ]]></body>
-      </method>
-
-      <method name="handleEvent">
-        <parameter name="aEvent"/>
-        <body><![CDATA[
-          switch (aEvent.type) {
-            case "load":
-              this.updateVisibility();
-              break;
-            case "resize":
-              if (aEvent.target != window)
-                break;
-
-              let sizemode = document.documentElement.getAttribute("sizemode");
-              TabsInTitlebar.allowedBy("sizemode",
-                                       sizemode == "maximized" || sizemode == "fullscreen");
-
-              var width = this.mTabstrip.boxObject.width;
-              if (width != this.mTabstripWidth) {
-                this.adjustTabstrip();
-                this._fillTrailingGap();
-                this._handleTabSelect();
-                this.mTabstripWidth = width;
-              }
-
-              this.tabbrowser.updateWindowResizers();
-              break;
-            case "mouseout":
-              // If the "related target" (the node to which the pointer went) is not
-              // a child of the current document, the mouse just left the window.
-              let relatedTarget = aEvent.relatedTarget;
-              if (relatedTarget && relatedTarget.ownerDocument == document)
-                break;
-            case "mousemove":
-              if (document.getElementById("tabContextMenu").state != "open")
-                this._unlockTabSizing();
-              break;
-          }
-        ]]></body>
-      </method>
-
-      <field name="_animateElement">
-        this.mTabstrip._scrollButtonDown;
-      </field>
-
-      <method name="_notifyBackgroundTab">
-        <parameter name="aTab"/>
-        <body><![CDATA[
-          if (aTab.pinned)
-            return;
-
-          var scrollRect = this.mTabstrip.scrollClientRect;
-          var tab = aTab.getBoundingClientRect();
-
-          // Is the new tab already completely visible?
-          if (scrollRect.left <= tab.left && tab.right <= scrollRect.right)
-            return;
-
-          if (this.mTabstrip.smoothScroll) {
-            let selected = !this.selectedItem.pinned &&
-                           this.selectedItem.getBoundingClientRect();
-
-            // Can we make both the new tab and the selected tab completely visible?
-            if (!selected ||
-                Math.max(tab.right - selected.left, selected.right - tab.left) <=
-                  scrollRect.width) {
-              this.mTabstrip.ensureElementIsVisible(aTab);
-              return;
-            }
-
-            this.mTabstrip._smoothScrollByPixels(this.mTabstrip._isRTLScrollbox ?
-                                                 selected.right - scrollRect.right :
-                                                 selected.left - scrollRect.left);
-          }
-
-          if (!this._animateElement.hasAttribute("notifybgtab")) {
-            this._animateElement.setAttribute("notifybgtab", "true");
-            setTimeout(function (ele) {
-              ele.removeAttribute("notifybgtab");
-            }, 150, this._animateElement);
-          }
-        ]]></body>
-      </method>
-
-      <method name="_getDragTargetTab">
-        <parameter name="event"/>
-        <body><![CDATA[
-          let tab = event.target.localName == "tab" ? event.target : null;
-          if (tab &&
-              (event.type == "drop" || event.type == "dragover") &&
-              event.dataTransfer.dropEffect == "link") {
-            let boxObject = tab.boxObject;
-            if (event.screenX < boxObject.screenX + boxObject.width * .25 ||
-                event.screenX > boxObject.screenX + boxObject.width * .75)
-              return null;
-          }
-          return tab;
-        ]]></body>
-      </method>
-
-      <method name="_getDropIndex">
-        <parameter name="event"/>
-        <body><![CDATA[
-          var tabs = this.childNodes;
-          var tab = this._getDragTargetTab(event);
-          if (window.getComputedStyle(this, null).direction == "ltr") {
-            for (let i = tab ? tab._tPos : 0; i < tabs.length; i++)
-              if (event.screenX < tabs[i].boxObject.screenX + tabs[i].boxObject.width / 2)
-                return i;
-          } else {
-            for (let i = tab ? tab._tPos : 0; i < tabs.length; i++)
-              if (event.screenX > tabs[i].boxObject.screenX + tabs[i].boxObject.width / 2)
-                return i;
-          }
-          return tabs.length;
-        ]]></body>
-      </method>
-
-      <method name="_setEffectAllowedForDataTransfer">
-        <parameter name="event"/>
-        <body><![CDATA[
-          var dt = event.dataTransfer;
-          // Disallow dropping multiple items
-          if (dt.mozItemCount > 1)
-            return dt.effectAllowed = "none";
-
-          var types = dt.mozTypesAt(0);
-          var sourceNode = null;
-          // tabs are always added as the first type
-          if (types[0] == TAB_DROP_TYPE) {
-            var sourceNode = dt.mozGetDataAt(TAB_DROP_TYPE, 0);
-            if (sourceNode instanceof XULElement &&
-                sourceNode.localName == "tab" &&
-                sourceNode.ownerDocument.defaultView instanceof ChromeWindow &&
-                sourceNode.ownerDocument.documentElement.getAttribute("windowtype") == "navigator:browser" &&
-                sourceNode.ownerDocument.defaultView.gBrowser.tabContainer == sourceNode.parentNode) {
-              // Do not allow transfering a private tab to a non-private window
-              // and vice versa.
-              if (PrivateBrowsingUtils.isWindowPrivate(window) !=
-                  PrivateBrowsingUtils.isWindowPrivate(sourceNode.ownerDocument.defaultView))
-                return dt.effectAllowed = "none";
-
-#ifdef XP_MACOSX
-              return dt.effectAllowed = event.altKey ? "copy" : "move";
-#else
-              return dt.effectAllowed = event.ctrlKey ? "copy" : "move";
-#endif
-            }
-          }
-
-          if (browserDragAndDrop.canDropLink(event)) {
-            // Here we need to do this manually
-            return dt.effectAllowed = dt.dropEffect = "link";
-          }
-          return dt.effectAllowed = "none";
-        ]]></body>
-      </method>
-
-      <method name="_handleNewTab">
-        <parameter name="tab"/>
-        <body><![CDATA[
-          if (tab.parentNode != this)
-            return;
-          tab._fullyOpen = true;
-
-          this.adjustTabstrip();
-
-          if (tab.getAttribute("selected") == "true") {
-            this._fillTrailingGap();
-            this._handleTabSelect();
-          } else {
-            if (tab.hasAttribute("skipbackgroundnotify")) {
-              tab.removeAttribute("skipbackgroundnotify");
-            } else {
-              this._notifyBackgroundTab(tab);
-            }
-          }
-
-          // XXXmano: this is a temporary workaround for bug 345399
-          // We need to manually update the scroll buttons disabled state
-          // if a tab was inserted to the overflow area or removed from it
-          // without any scrolling and when the tabbar has already
-          // overflowed.
-          this.mTabstrip._updateScrollButtonsDisabledState();
-        ]]></body>
-      </method>
-
-      <method name="_canAdvanceToTab">
-        <parameter name="aTab"/>
-        <body>
-        <![CDATA[
-          return !aTab.closing;
-        ]]>
-        </body>
-      </method>
-
-      <method name="_handleTabTelemetryStart">
-        <parameter name="aTab"/>
-        <parameter name="aURI"/>
-        <body>
-        <![CDATA[
-          // Animation-smoothness telemetry/logging
-          if (this._tabAnimationLoggingEnabled) {
-            if (aURI == "about:newtab" && (aTab._tPos == 1 || aTab._tPos == 2)) {
-              // Indicate newtab page animation where other tabs are unaffected
-              // (for which case, the 2nd or 3rd tabs are good representatives, even if not absolute)
-              aTab._recordingTabOpenPlain = true;
-            }
-            aTab._recordingHandle = window.QueryInterface(Ci.nsIInterfaceRequestor)
-                                          .getInterface(Ci.nsIDOMWindowUtils)
-                                          .startFrameTimeRecording();
-          }
-
-          // Overall animation duration
-          aTab._animStartTime = Date.now();
-        ]]>
-        </body>
-      </method>
-
-      <method name="_handleTabTelemetryEnd">
-        <parameter name="aTab"/>
-        <body>
-        <![CDATA[
-          if (!aTab._animStartTime) {
-            return;
-          }
-
-          aTab._animStartTime = 0;
-
-          // Handle tab animation smoothness telemetry/logging of frame intervals and paint times
-          if (!("_recordingHandle" in aTab)) {
-            return;
-          }
-
-          let paints = {};
-          let intervals = window.QueryInterface(Ci.nsIInterfaceRequestor)
-                                .getInterface(Ci.nsIDOMWindowUtils)
-                                .stopFrameTimeRecording(aTab._recordingHandle, paints);
-          delete aTab._recordingHandle;
-          paints = paints.value; // The result array itself.
-          let frameCount = intervals.length;
-
-          if (this._tabAnimationLoggingEnabled) {
-            let msg = "Tab " + (aTab.closing ? "close" : "open") + " (Frame-interval / paint-processing):\n";
-            for (let i = 0; i < frameCount; i++) {
-              msg += Math.round(intervals[i]) + " / " + Math.round(paints[i]) + "\n";
-            }
-            Services.console.logStringMessage(msg);
-          }
-
-          // For telemetry, the first frame interval is not useful since it may represent an interval
-          // to a relatively old frame (prior to recording start). So we'll ignore it for the average.
-          // But if we recorded only 1 frame (very rare), then the first paint duration is a good
-          // representative of the first frame interval for our cause (indicates very bad animation).
-          // First paint duration is always useful for us.
-          if (frameCount > 0) {
-            let averageInterval = 0;
-            let averagePaint = paints[0];
-            for (let i = 1; i < frameCount; i++) {
-              averageInterval += intervals[i];
-              averagePaint    += paints[i];
-            };
-            averagePaint /= frameCount;
-            averageInterval = (frameCount == 1)
-                              ? averagePaint
-                              : averageInterval / (frameCount - 1);
-
-            if (aTab._recordingTabOpenPlain) {
-              delete aTab._recordingTabOpenPlain;
-            }
-          }
-        ]]>
-        </body>
-      </method>
-
-      <!-- Deprecated stuff, implemented for backwards compatibility. -->
-      <property name="mTabstripClosebutton" readonly="true"
-                onget="return document.getElementById('tabs-closebutton');"/>
-      <property name="mAllTabsPopup" readonly="true"
-                onget="return document.getElementById('alltabs-popup');"/>
-    </implementation>
-
-    <handlers>
-      <handler event="TabSelect" action="this._handleTabSelect();"/>
-
-      <handler event="transitionend"><![CDATA[
-        if (event.propertyName != "max-width")
-          return;
-
-        var tab = event.target;
-
-        this._handleTabTelemetryEnd(tab);
-
-        if (tab.getAttribute("fadein") == "true") {
-          if (tab._fullyOpen)
-            this.adjustTabstrip();
-          else
-            this._handleNewTab(tab);
-        } else if (tab.closing) {
-          this.tabbrowser._endRemoveTab(tab);
-        }
-      ]]></handler>
-
-      <handler event="dblclick"><![CDATA[
-#ifndef XP_MACOSX
-        // When the tabbar has an unified appearance with the titlebar
-        // and menubar, a double-click in it should have the same behavior
-        // as double-clicking the titlebar
-        if (TabsInTitlebar.enabled ||
-            (TabsOnTop.enabled && this.parentNode._dragBindingAlive))
-          return;
-#endif
-
-        if (event.button != 0 ||
-            event.originalTarget.localName != "box")
-          return;
-
-        // See comments in the "mousedown" and "click" event handlers of the
-        // tabbrowser-tabs binding.
-        if (!this._blockDblClick)
-          BrowserOpenTab();
-
-        event.preventDefault();
-      ]]></handler>
-
-      <!-- Consider that the in-tab close button is only shown on the active
-           tab. When clicking on an inactive tab at the position where the
-           close button will appear during the click, no "click" event will be
-           dispatched, because the mousedown and mouseup events don't have the
-           same event target. For that reason use "mousedown" instead of "click"
-           to implement in-tab close button behavior. (Pale Moon UXP issue #775)
-      -->
-      <handler event="mousedown" button="0" phase="capturing"><![CDATA[
-        /* The only sequence in which a second click event (i.e. dblclik)
-         * can be dispatched on an in-tab close button is when it is shown
-         * after the first click (i.e. the first click event was dispatched
-         * on the tab). This happens when we show the close button only on
-         * the active tab. (bug 352021)
-         * The only sequence in which a third click event can be dispatched
-         * on an in-tab close button is when the tab was opened with a
-         * double click on the tabbar. (bug 378344)
-         * In both cases, it is most likely that the close button area has
-         * been accidentally clicked, therefore we do not close the tab.
-         *
-         * We don't want to ignore processing of more than one click event,
-         * though, since the user might actually be repeatedly clicking to
-         * close many tabs at once.
-         *
-         * Also prevent errant doubleclick on the close button from opening
-         * a new tab (bug 343628):
-         * Since we're removing the event target, if the user double-clicks
-         * the button, the dblclick event will be dispatched with the tabbar
-         * as its event target (and explicit/originalTarget), which treats
-         * that as a mouse gesture for opening a new tab.
-         * In this context, we're manually blocking the dblclick event.
-         */
-
-        // Reset flags at the beginning of a series of clicks:
-        if (event.detail == 1) {
-          this.flagClickOnCloseButton = false;
-          this.flagActivateTabOrClickOnTabbar = false;
-        }
-
-        this.blockCloseButtonOnDblclick = this.flagActivateTabOrClickOnTabbar;
-        this._blockDblClick = this.flagClickOnCloseButton;
-
-        // Set flags:
-        let eventTargetIsCloseButton =
-            event.originalTarget.classList.contains("tab-close-button");
-        this.flagClickOnCloseButton = eventTargetIsCloseButton;
-        this.flagActivateTabOrClickOnTabbar =
-            ((!eventTargetIsCloseButton && event.detail == 1) ||
-             event.originalTarget.localName == "box");
-      ]]></handler>
-
-      <handler event="click" button="0"><![CDATA[
-        // See comment in the "mousedown" event handler of the
-        // tabbrowser-tabs binding.
-        if (event.originalTarget.classList.contains("tab-close-button") &&
-            !this.blockCloseButtonOnDblclick) {
-          gBrowser.removeTab(document.getBindingParent(event.originalTarget),
-                             {animate: true, byMouse: true,});
-          this._blockDblClick = true;
-        }
-      ]]></handler>
-
-      <handler event="click" button="1"><![CDATA[
-        if (event.target.localName == "tab") {
-          if (this.childNodes.length > 1 || !this._closeWindowWithLastTab)
-            this.tabbrowser.removeTab(event.target, {animate: true, byMouse: true});
-        } else if (event.originalTarget.localName == "box") {
-          BrowserOpenTab();
-        } else {
-          return;
-        }
-
-        event.stopPropagation();
-      ]]></handler>
-
-      <handler event="keypress"><![CDATA[
-        if (event.altKey || event.shiftKey ||
-#ifdef XP_MACOSX
-            !event.metaKey)
-#else
-            !event.ctrlKey || event.metaKey)
-#endif
-          return;
-
-        switch (event.keyCode) {
-          case KeyEvent.DOM_VK_UP:
-            this.tabbrowser.moveTabBackward();
-            break;
-          case KeyEvent.DOM_VK_DOWN:
-            this.tabbrowser.moveTabForward();
-            break;
-          case KeyEvent.DOM_VK_RIGHT:
-          case KeyEvent.DOM_VK_LEFT:
-            this.tabbrowser.moveTabOver(event);
-            break;
-          case KeyEvent.DOM_VK_HOME:
-            this.tabbrowser.moveTabToStart();
-            break;
-          case KeyEvent.DOM_VK_END:
-            this.tabbrowser.moveTabToEnd();
-            break;
-          default:
-            // Stop the keypress event for the above keyboard
-            // shortcuts only.
-            return;
-        }
-        event.stopPropagation();
-        event.preventDefault();
-      ]]></handler>
-
-      <handler event="dragstart"><![CDATA[
-        var tab = this._getDragTargetTab(event);
-        if (!tab)
-          return;
-
-        let dt = event.dataTransfer;
-        dt.mozSetDataAt(TAB_DROP_TYPE, tab, 0);
-        let browser = tab.linkedBrowser;
-
-        // We must not set text/x-moz-url or text/plain data here,
-        // otherwise trying to deatch the tab by dropping it on the desktop
-        // may result in an "internet shortcut"
-        dt.mozSetDataAt("text/x-moz-text-internal", browser.currentURI.spec, 0);
-
-        // Set the cursor to an arrow during tab drags.
-        dt.mozCursor = "default";
-
-        // Create a canvas to which we capture the current tab.
-        // Until canvas is HiDPI-aware (bug 780362), we need to scale the desired
-        // canvas size (in CSS pixels) to the window's backing resolution in order
-        // to get a full-resolution drag image for use on HiDPI displays.
-        let windowUtils = window.getInterface(Ci.nsIDOMWindowUtils);
-        let scale = windowUtils.screenPixelsPerCSSPixel / windowUtils.fullZoom;
-        let canvas = document.createElementNS("http://www.w3.org/1999/xhtml", "canvas");
-        canvas.mozOpaque = true;
-        canvas.width = 160 * scale;
-        canvas.height = 90 * scale;
-        PageThumbs.captureToCanvas(browser, canvas);
-        dt.setDragImage(canvas, -16 * scale, -16 * scale);
-
-        // _dragData.offsetX/Y give the coordinates that the mouse should be
-        // positioned relative to the corner of the new window created upon
-        // dragend such that the mouse appears to have the same position
-        // relative to the corner of the dragged tab.
-        function clientX(ele) ele.getBoundingClientRect().left;
-        let tabOffsetX = clientX(tab) - clientX(this);
-        tab._dragData = {
-          offsetX: event.screenX - window.screenX - tabOffsetX,
-          offsetY: event.screenY - window.screenY,
-          scrollX: this.mTabstrip.scrollPosition,
-          screenX: event.screenX
-        };
-
-        event.stopPropagation();
-      ]]></handler>
-
-      <handler event="dragover"><![CDATA[
-        var effects = this._setEffectAllowedForDataTransfer(event);
-
-        var ind = this._tabDropIndicator;
-        if (effects == "" || effects == "none") {
-          ind.collapsed = true;
-          return;
-        }
-        event.preventDefault();
-        event.stopPropagation();
-
-        var tabStrip = this.mTabstrip;
-        var ltr = (window.getComputedStyle(this, null).direction == "ltr");
-
-        // autoscroll the tab strip if we drag over the scroll
-        // buttons, even if we aren't dragging a tab, but then
-        // return to avoid drawing the drop indicator
-        var pixelsToScroll = 0;
-        if (this.getAttribute("overflow") == "true") {
-          var targetAnonid = event.originalTarget.getAttribute("anonid");
-          switch (targetAnonid) {
-            case "scrollbutton-up":
-              pixelsToScroll = tabStrip.scrollIncrement * -1;
-              break;
-            case "scrollbutton-down":
-              pixelsToScroll = tabStrip.scrollIncrement;
-              break;
-          }
-          if (pixelsToScroll)
-            tabStrip.scrollByPixels((ltr ? 1 : -1) * pixelsToScroll);
-        }
-
-        if (effects == "move" &&
-            this == event.dataTransfer.mozGetDataAt(TAB_DROP_TYPE, 0).parentNode) {
-          ind.collapsed = true;
-          this._animateTabMove(event);
-          return;
-        }
-
-        this._finishAnimateTabMove();
-
-        if (effects == "link") {
-          let tab = this._getDragTargetTab(event);
-          if (tab) {
-            if (!this._dragTime)
-              this._dragTime = Date.now();
-            if (Date.now() >= this._dragTime + this._dragOverDelay)
-              this.selectedItem = tab;
-            ind.collapsed = true;
-            return;
-          }
-        }
-
-        var rect = tabStrip.getBoundingClientRect();
-        var newMargin;
-        if (pixelsToScroll) {
-          // if we are scrolling, put the drop indicator at the edge
-          // so that it doesn't jump while scrolling
-          let scrollRect = tabStrip.scrollClientRect;
-          let minMargin = scrollRect.left - rect.left;
-          let maxMargin = Math.min(minMargin + scrollRect.width,
-                                   scrollRect.right);
-          if (!ltr)
-            [minMargin, maxMargin] = [this.clientWidth - maxMargin,
-                                      this.clientWidth - minMargin];
-          newMargin = (pixelsToScroll > 0) ? maxMargin : minMargin;
-        }
-        else {
-          let newIndex = this._getDropIndex(event);
-          if (newIndex == this.childNodes.length) {
-            let tabRect = this.childNodes[newIndex-1].getBoundingClientRect();
-            if (ltr)
-              newMargin = tabRect.right - rect.left;
-            else
-              newMargin = rect.right - tabRect.left;
-          }
-          else {
-            let tabRect = this.childNodes[newIndex].getBoundingClientRect();
-            if (ltr)
-              newMargin = tabRect.left - rect.left;
-            else
-              newMargin = rect.right - tabRect.right;
-          }
-        }
-
-        ind.collapsed = false;
-
-        newMargin += ind.clientWidth / 2;
-        if (!ltr)
-          newMargin *= -1;
-
-        ind.style.transform = "translate(" + Math.round(newMargin) + "px)";
-        ind.style.MozMarginStart = (-ind.clientWidth) + "px";
-      ]]></handler>
-
-      <handler event="drop"><![CDATA[
-        var dt = event.dataTransfer;
-        var dropEffect = dt.dropEffect;
-        var draggedTab;
-        if (dropEffect != "link") { // copy or move
-          draggedTab = dt.mozGetDataAt(TAB_DROP_TYPE, 0);
-          // not our drop then
-          if (!draggedTab)
-            return;
-        }
-
-        this._tabDropIndicator.collapsed = true;
-        event.stopPropagation();
-        if (draggedTab && dropEffect == "copy") {
-          // copy the dropped tab (wherever it's from)
-          let newIndex = this._getDropIndex(event);
-          let newTab = this.tabbrowser.duplicateTab(draggedTab);
-          this.tabbrowser.moveTabTo(newTab, newIndex);
-          if (draggedTab.parentNode != this || event.shiftKey)
-            this.selectedItem = newTab;
-        } else if (draggedTab && draggedTab.parentNode == this) {
-          this._finishAnimateTabMove();
-
-          // actually move the dragged tab
-          if ("animDropIndex" in draggedTab._dragData) {
-            let newIndex = draggedTab._dragData.animDropIndex;
-            if (newIndex > draggedTab._tPos)
-              newIndex--;
-            this.tabbrowser.moveTabTo(draggedTab, newIndex);
-          }
-        } else if (draggedTab) {
-          // swap the dropped tab with a new one we create and then close
-          // it in the other window (making it seem to have moved between
-          // windows)
-          let newIndex = this._getDropIndex(event);
-          let newTab = this.tabbrowser.addTab("about:blank");
-          let newBrowser = this.tabbrowser.getBrowserForTab(newTab);
-          // Stop the about:blank load
-          newBrowser.stop();
-          // make sure it has a docshell
-          newBrowser.docShell;
-
-          let numPinned = this.tabbrowser._numPinnedTabs;
-          if (newIndex < numPinned || draggedTab.pinned && newIndex == numPinned)
-            this.tabbrowser.pinTab(newTab);
-          this.tabbrowser.moveTabTo(newTab, newIndex);
-
-          // We need to select the tab before calling swapBrowsersAndCloseOther
-          // so that window.content in chrome windows points to the right tab
-          // when pagehide/show events are fired.
-          this.tabbrowser.selectedTab = newTab;
-
-          draggedTab.parentNode._finishAnimateTabMove();
-          this.tabbrowser.swapBrowsersAndCloseOther(newTab, draggedTab);
-
-          // Call updateCurrentBrowser to make sure the URL bar is up to date
-          // for our new tab after we've done swapBrowsersAndCloseOther.
-          this.tabbrowser.updateCurrentBrowser(true);
-        } else {
-          // Pass true to disallow dropping javascript: or data: urls
-          let links;
-          try {
-            links = browserDragAndDrop.dropLinks(event, true);
-          } catch (ex) {}
-
-//          // valid urls don't contain spaces ' '; if we have a space it isn't a valid url.
-//          if (!url || url.includes(" ")) //PMed
-          if (!links || links.length === 0) //FF
-            return;
-
-          let inBackground = Services.prefs.getBoolPref("browser.tabs.loadInBackground");
-
-          if (event.shiftKey)
-            inBackground = !inBackground;
-
-          let targetTab = this._getDragTargetTab(event);
-          let replace = !(!targetTab || dropEffect == "copy");
-          let newIndex = this._getDropIndex(event);
-          let urls = links.map(link => link.url);
-          this.tabbrowser.loadTabs(urls, {
-            inBackground,
-            replace,
-            allowThirdPartyFixup: true,
-            targetTab,
-            newIndex,
-          });
-        }
-
-        if (draggedTab) {
-          delete draggedTab._dragData;
-        }
-      ]]></handler>
-
-      <handler event="dragend"><![CDATA[
-        // Note: while this case is correctly handled here, this event
-        // isn't dispatched when the tab is moved within the tabstrip,
-        // see bug 460801.
-
-        this._finishAnimateTabMove();
-
-        var dt = event.dataTransfer;
-        var draggedTab = dt.mozGetDataAt(TAB_DROP_TYPE, 0);
-        if (dt.mozUserCancelled || dt.dropEffect != "none") {
-          delete draggedTab._dragData;
-          return;
-        }
-
-        // Disable detach within the browser toolbox
-        var eX = event.screenX;
-        var eY = event.screenY;
-        var wX = window.screenX;
-        // check if the drop point is horizontally within the window
-        if (eX > wX && eX < (wX + window.outerWidth)) {
-          let bo = this.mTabstrip.boxObject;
-          // also avoid detaching if the the tab was dropped too close to
-          // the tabbar (half a tab)
-          let endScreenY = bo.screenY + 1.5 * bo.height;
-          if (eY < endScreenY && eY > window.screenY)
-            return;
-        }
-
-        // screen.availLeft et. al. only check the screen that this window is on,
-        // but we want to look at the screen the tab is being dropped onto.
-        var sX = {}, sY = {}, sWidth = {}, sHeight = {};
-        Cc["@mozilla.org/gfx/screenmanager;1"]
-          .getService(Ci.nsIScreenManager)
-          .screenForRect(eX, eY, 1, 1)
-          .GetAvailRect(sX, sY, sWidth, sHeight);
-        // ensure new window entirely within screen
-        var winWidth = Math.min(window.outerWidth, sWidth.value);
-        var winHeight = Math.min(window.outerHeight, sHeight.value);
-        var left = Math.min(Math.max(eX - draggedTab._dragData.offsetX, sX.value),
-                            sX.value + sWidth.value - winWidth);
-        var top = Math.min(Math.max(eY - draggedTab._dragData.offsetY, sY.value),
-                           sY.value + sHeight.value - winHeight);
-
-        delete draggedTab._dragData;
-
-        if (this.tabbrowser.tabs.length == 1) {
-          // resize _before_ move to ensure the window fits the new screen.  if
-          // the window is too large for its screen, the window manager may do
-          // automatic repositioning.
-          window.resizeTo(winWidth, winHeight);
-          window.moveTo(left, top);
-          window.focus();
-        } else {
-          this.tabbrowser.replaceTabWithWindow(draggedTab, { screenX: left,
-                                                             screenY: top,
-#ifndef XP_WIN
-                                                             outerWidth: winWidth,
-                                                             outerHeight: winHeight
-#endif
-                                                             });
-        }
-        event.stopPropagation();
-      ]]></handler>
-
-      <handler event="dragexit"><![CDATA[
-        this._dragTime = 0;
-
-        // This does not work at all (see bug 458613)
-        var target = event.relatedTarget;
-        while (target && target != this)
-          target = target.parentNode;
-        if (target)
-          return;
-
-        this._tabDropIndicator.collapsed = true;
-        event.stopPropagation();
-      ]]></handler>
-    </handlers>
-  </binding>
-
-  <!-- close-tab-button binding
-       This binding relies on the structure of the tabbrowser binding.
-       Therefore it should only be used as a child of the tab or the tabs
-       element (in both cases, when they are anonymous nodes of <tabbrowser>).
-  -->
-  <binding id="tabbrowser-close-tab-button"
-           extends="chrome://global/content/bindings/toolbarbutton.xml#toolbarbutton-image">
-    <handlers>
-      <handler event="dragstart">
-        event.stopPropagation();
-      </handler>
-    </handlers>
-  </binding>
-
-  <binding id="tabbrowser-tab" display="xul:hbox"
-           extends="chrome://global/content/bindings/tabbox.xml#tab">
-    <resources>
-      <stylesheet src="chrome://browser/content/tabbrowser.css"/>
-    </resources>
-
-    <content context="tabContextMenu" closetabtext="&closeTab.label;">
-      <xul:stack class="tab-stack" flex="1">
-        <xul:hbox xbl:inherits="pinned,selected,titlechanged"
-                  class="tab-background">
-          <xul:hbox xbl:inherits="pinned,selected,titlechanged"
-                    class="tab-background-start"/>
-          <xul:hbox xbl:inherits="pinned,selected,titlechanged"
-                    class="tab-background-middle"/>
-          <xul:hbox xbl:inherits="pinned,selected,titlechanged"
-                    class="tab-background-end"/>
-        </xul:hbox>
-        <xul:hbox xbl:inherits="pinned,selected,titlechanged"
-                  class="tab-content" align="center">
-          <xul:image xbl:inherits="fadein,pinned,busy,progress,selected"
-                     class="tab-throbber"
-                     role="presentation"
-                     layer="true" />
-          <xul:image xbl:inherits="validate,src=image,fadein,pinned,selected"
-                     class="tab-icon-image"
-                     role="presentation"
-                     anonid="tab-icon"/>
-          <xul:image xbl:inherits="busy,soundplaying,soundplaying-scheduledremoval,pinned,muted,blocked,selected"
-                     anonid="overlay-icon"
-                     class="tab-icon-overlay"
-                     role="presentation"/>
-          <xul:label flex="1"
-                     xbl:inherits="value=label,crop,accesskey,fadein,pinned,selected"
-                     class="tab-text tab-label"
-                     role="presentation"/>
-          <xul:image xbl:inherits="soundplaying,soundplaying-scheduledremoval,pinned,muted,blocked,selected"
-                     anonid="soundplaying-icon"
-                     class="tab-icon-sound"
-                     role="presentation"/>
-          <xul:toolbarbutton anonid="close-button"
-                             xbl:inherits="fadein,pinned,selected"
-                             class="tab-close-button close-icon"/>
-        </xul:hbox>
-      </xul:stack>
-    </content>
-
-    <implementation>
-      <property name="pinned" readonly="true">
-        <getter>
-          return this.getAttribute("pinned") == "true";
-        </getter>
-      </property>
-      <property name="hidden" readonly="true">
-        <getter>
-          return this.getAttribute("hidden") == "true";
-        </getter>
-      </property>
-
-      <field name="mOverCloseButton">false</field>
-      <property name="_overPlayingIcon" readonly="true">
-        <getter><![CDATA[
-          let iconVisible = this.hasAttribute("soundplaying") ||
-                            this.hasAttribute("muted") ||
-                            this.hasAttribute("blocked");
-          let soundPlayingIcon =
-            document.getAnonymousElementByAttribute(this, "anonid", "soundplaying-icon");
-          let overlayIcon =
-            document.getAnonymousElementByAttribute(this, "anonid", "overlay-icon");
-
-          return soundPlayingIcon && soundPlayingIcon.matches(":hover") ||
-                 (overlayIcon && overlayIcon.matches(":hover") && iconVisible);
-        ]]></getter>
-      </property>
-      <field name="mCorrespondingMenuitem">null</field>
-      <field name="closing">false</field>
-      <field name="lastAccessed">0</field>
-      
-      <method name="toggleMuteAudio">
-        <parameter name="aMuteReason"/>
-        <body>
-        <![CDATA[
-          let tabContainer = this.parentNode;
-          let browser = this.linkedBrowser;
-          let modifiedAttrs = [];
-          if (browser.audioBlocked) {
-            this.removeAttribute("blocked");
-            modifiedAttrs.push("blocked");
-
-            // We don't want sound icon flickering between "blocked", "none" and
-            // "sound-playing", here adding the "soundplaying" is to keep the
-            // transition smoothly.
-            if (!this.hasAttribute("soundplaying")) {
-              this.setAttribute("soundplaying", true);
-              modifiedAttrs.push("soundplaying");
-            }
-
-            browser.resumeMedia();
-          } else {
-            if (browser.audioMuted) {
-              browser.unmute();
-              this.removeAttribute("muted");
-            } else {
-              browser.mute();
-              this.setAttribute("muted", "true");
-            }
-            this.muteReason = aMuteReason || null;
-            modifiedAttrs.push("muted");
-          }
-          tabContainer.tabbrowser._tabAttrModified(this, modifiedAttrs);
-        ]]>
-        </body>
-      </method>
-    </implementation>
-
-    <handlers>
-      <handler event="mouseover"><![CDATA[
-        let anonid = event.originalTarget.getAttribute("anonid");
-        if (anonid == "close-button")
-          this.mOverCloseButton = true;
-
-        let tab = event.target;
-        if (tab.closing)
-          return;
-
-        let tabContainer = this.parentNode;
-        let visibleTabs = tabContainer.tabbrowser.visibleTabs;
-        let tabIndex = visibleTabs.indexOf(tab);
-        if (tabIndex == 0) {
-          tabContainer._beforeHoveredTab = null;
-        } else {
-          let candidate = visibleTabs[tabIndex - 1];
-          if (!candidate.selected) {
-            tabContainer._beforeHoveredTab = candidate;
-            candidate.setAttribute("beforehovered", "true");
-          }
-        }
-
-        if (tabIndex == visibleTabs.length - 1) {
-          tabContainer._afterHoveredTab = null;
-        } else {
-          let candidate = visibleTabs[tabIndex + 1];
-          if (!candidate.selected) {
-            tabContainer._afterHoveredTab = candidate;
-            candidate.setAttribute("afterhovered", "true");
-          }
-        }
-      ]]></handler>
-      <handler event="mouseout"><![CDATA[
-        let anonid = event.originalTarget.getAttribute("anonid");
-        if (anonid == "close-button")
-          this.mOverCloseButton = false;
-
-        let tabContainer = this.parentNode;
-        if (tabContainer._beforeHoveredTab) {
-          tabContainer._beforeHoveredTab.removeAttribute("beforehovered");
-          tabContainer._beforeHoveredTab = null;
-        }
-        if (tabContainer._afterHoveredTab) {
-          tabContainer._afterHoveredTab.removeAttribute("afterhovered");
-          tabContainer._afterHoveredTab = null;
-        }
-      ]]></handler>
-      <handler event="dragstart" phase="capturing">
-        this.style.MozUserFocus = '';
-      </handler>
-      <handler event="mousedown" phase="capturing">
-      <![CDATA[
-        if (this.selected) {
-          this.style.MozUserFocus = 'ignore';
-          this.clientTop; // just using this to flush style updates
-        } else if (this.mOverCloseButton ||
-                   this._overPlayingIcon) {
-          // Prevent tabbox.xml from selecting the tab.
-          event.stopPropagation();
-        }
-      ]]>
-      </handler>
-      <handler event="mouseup">
-        this.style.MozUserFocus = '';
-      </handler>
-      <handler event="click">
-      <![CDATA[
-        if (event.button != 0) {
-          return;
-        }
-
-        if (this._overPlayingIcon) {
-          this.toggleMuteAudio();
-        }
-      ]]>
-      </handler>
-    </handlers>
-  </binding>
-
-  <binding id="tabbrowser-alltabs-popup"
-           extends="chrome://global/content/bindings/popup.xml#popup">
-    <implementation implements="nsIDOMEventListener">
-      <method name="_tabOnAttrModified">
-        <parameter name="aEvent"/>
-        <body><![CDATA[
-          var tab = aEvent.target;
-          if (tab.mCorrespondingMenuitem)
-            this._setMenuitemAttributes(tab.mCorrespondingMenuitem, tab);
-        ]]></body>
-      </method>
-
-      <method name="_tabOnTabClose">
-        <parameter name="aEvent"/>
-        <body><![CDATA[
-          var tab = aEvent.target;
-          if (tab.mCorrespondingMenuitem)
-            this.removeChild(tab.mCorrespondingMenuitem);
-        ]]></body>
-      </method>
-
-      <method name="handleEvent">
-        <parameter name="aEvent"/>
-        <body><![CDATA[
-          switch (aEvent.type) {
-            case "TabAttrModified":
-              this._tabOnAttrModified(aEvent);
-              break;
-            case "TabClose":
-              this._tabOnTabClose(aEvent);
-              break;
-            case "scroll":
-              this._updateTabsVisibilityStatus();
-              break;
-          }
-        ]]></body>
-      </method>
-
-      <method name="_updateTabsVisibilityStatus">
-        <body><![CDATA[
-          var tabContainer = gBrowser.tabContainer;
-          // We don't want menu item decoration unless there is overflow.
-          if (tabContainer.getAttribute("overflow") != "true")
-            return;
-
-          var tabstripBO = tabContainer.mTabstrip.scrollBoxObject;
-          for (var i = 0; i < this.childNodes.length; i++) {
-            let curTab = this.childNodes[i].tab;
-            let curTabBO = curTab.boxObject;
-            if (curTabBO.screenX >= tabstripBO.screenX &&
-                curTabBO.screenX + curTabBO.width <= tabstripBO.screenX + tabstripBO.width)
-              this.childNodes[i].setAttribute("tabIsVisible", "true");
-            else
-              this.childNodes[i].removeAttribute("tabIsVisible");
-          }
-        ]]></body>
-      </method>
-
-      <method name="_createTabMenuItem">
-        <parameter name="aTab"/>
-        <body><![CDATA[
-          var menuItem = document.createElementNS(
-            "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul",
-            "menuitem");
-
-          menuItem.setAttribute("class", "menuitem-iconic alltabs-item menuitem-with-favicon");
-
-          this._setMenuitemAttributes(menuItem, aTab);
-
-          if (!aTab.mCorrespondingMenuitem) {
-            aTab.mCorrespondingMenuitem = menuItem;
-            menuItem.tab = aTab;
-
-            this.appendChild(menuItem);
-          }
-        ]]></body>
-      </method>
-
-      <method name="_setMenuitemAttributes">
-        <parameter name="aMenuitem"/>
-        <parameter name="aTab"/>
-        <body><![CDATA[
-          aMenuitem.setAttribute("label", aTab.label);
-          aMenuitem.setAttribute("crop", aTab.getAttribute("crop"));
-
-          if (aTab.hasAttribute("busy")) {
-            aMenuitem.setAttribute("busy", aTab.getAttribute("busy"));
-            aMenuitem.removeAttribute("image");
-          } else {
-            aMenuitem.setAttribute("image", aTab.getAttribute("image"));
-            aMenuitem.removeAttribute("busy");
-          }
-
-          if (aTab.hasAttribute("pending"))
-            aMenuitem.setAttribute("pending", aTab.getAttribute("pending"));
-          else
-            aMenuitem.removeAttribute("pending");
-
-          if (aTab.selected)
-            aMenuitem.setAttribute("selected", "true");
-          else
-            aMenuitem.removeAttribute("selected");
-
-          function addEndImage() {
-            let endImage = document.createElement("image");
-            endImage.setAttribute("class", "allTabs-endimage");
-            let endImageContainer = document.createElement("hbox");
-            endImageContainer.setAttribute("align", "center");
-            endImageContainer.setAttribute("pack", "center");
-            endImageContainer.appendChild(endImage);
-            aMenuitem.appendChild(endImageContainer);
-            return endImage;
-          }
-
-          if (aMenuitem.firstChild)
-            aMenuitem.firstChild.remove();
-          if (aTab.hasAttribute("muted"))
-            addEndImage().setAttribute("muted", "true");
-          else if (aTab.hasAttribute("soundplaying"))
-            addEndImage().setAttribute("soundplaying", "true");
-        ]]></body>
-      </method>
-    </implementation>
-
-    <handlers>
-      <handler event="popupshowing">
-      <![CDATA[
-        var tabcontainer = gBrowser.tabContainer;
-
-        // Listen for changes in the tab bar.
-        tabcontainer.addEventListener("TabAttrModified", this, false);
-        tabcontainer.addEventListener("TabClose", this, false);
-        tabcontainer.mTabstrip.addEventListener("scroll", this, false);
-
-        let tabs = gBrowser.visibleTabs;
-        for (var i = 0; i < tabs.length; i++) {
-          if (!tabs[i].pinned)
-            this._createTabMenuItem(tabs[i]);
-        }
-        this._updateTabsVisibilityStatus();
-      ]]></handler>
-
-      <handler event="popuphidden">
-      <![CDATA[
-        // clear out the menu popup and remove the listeners
-        for (let i = this.childNodes.length - 1; i >= 0; i--) {
-          let menuItem = this.childNodes[i];
-          if (menuItem.tab) {
-            menuItem.tab.mCorrespondingMenuitem = null;
-            this.removeChild(menuItem);
-          }
-        }
-        var tabcontainer = gBrowser.tabContainer;
-        tabcontainer.mTabstrip.removeEventListener("scroll", this, false);
-        tabcontainer.removeEventListener("TabAttrModified", this, false);
-        tabcontainer.removeEventListener("TabClose", this, false);
-      ]]></handler>
-
-      <handler event="DOMMenuItemActive">
-      <![CDATA[
-        var tab = event.target.tab;
-        if (tab) {
-          let overLink = tab.linkedBrowser.currentURI.spec;
-          if (overLink == "about:blank")
-            overLink = "";
-          XULBrowserWindow.setOverLink(overLink, null);
-        }
-      ]]></handler>
-
-      <handler event="DOMMenuItemInactive">
-      <![CDATA[
-        XULBrowserWindow.setOverLink("", null);
-      ]]></handler>
-
-      <handler event="command"><![CDATA[
-        if (event.target.tab)
-          gBrowser.selectedTab = event.target.tab;
-      ]]></handler>
-
-    </handlers>
-  </binding>
-
-  <binding id="statuspanel" display="xul:hbox">
-    <content>
-      <xul:hbox class="statuspanel-inner">
-        <xul:label class="statuspanel-label"
-                   role="status"
-                   aria-live="off"
-                   xbl:inherits="value=label,crop,mirror"
-                   flex="1"
-                   crop="end"/>
-      </xul:hbox>
-    </content>
-
-    <implementation implements="nsIDOMEventListener">
-      <constructor><![CDATA[
-        window.addEventListener("resize", this, false);
-      ]]></constructor>
-
-      <destructor><![CDATA[
-        window.removeEventListener("resize", this, false);
-        MousePosTracker.removeListener(this);
-      ]]></destructor>
-
-      <property name="label">
-        <setter><![CDATA[
-          if (!this.label) {
-            this.removeAttribute("mirror");
-            this.removeAttribute("sizelimit");
-          }
-
-          this.style.minWidth = this.getAttribute("type") == "status" &&
-                                this.getAttribute("previoustype") == "status"
-                                  ? getComputedStyle(this).width : "";
-
-          if (val) {
-            this.setAttribute("label", val);
-            this.removeAttribute("inactive");
-            this._calcMouseTargetRect();
-            MousePosTracker.addListener(this);
-          } else {
-            this.setAttribute("inactive", "true");
-            MousePosTracker.removeListener(this);
-          }
-
-          return val;
-        ]]></setter>
-        <getter>
-          return this.hasAttribute("inactive") ? "" : this.getAttribute("label");
-        </getter>
-      </property>
-
-      <method name="getMouseTargetRect">
-        <body><![CDATA[
-          return this._mouseTargetRect;
-        ]]></body>
-      </method>
-
-      <method name="onMouseEnter">
-        <body>
-          this._mirror();
-        </body>
-      </method>
-
-      <method name="onMouseLeave">
-        <body>
-          this._mirror();
-        </body>
-      </method>
-
-      <method name="handleEvent">
-        <parameter name="event"/>
-        <body><![CDATA[
-          if (!this.label)
-            return;
-
-          switch (event.type) {
-            case "resize":
-              this._calcMouseTargetRect();
-              break;
-          }
-        ]]></body>
-      </method>
-
-      <method name="_calcMouseTargetRect">
-        <body><![CDATA[
-          let alignRight = false;
-
-          if (getComputedStyle(document.documentElement).direction == "rtl")
-            alignRight = !alignRight;
-
-          let rect = this.getBoundingClientRect();
-          this._mouseTargetRect = {
-            top:    rect.top,
-            bottom: rect.bottom,
-            left:   alignRight ? window.innerWidth - rect.width : 0,
-            right:  alignRight ? window.innerWidth : rect.width
-          };
-        ]]></body>
-      </method>
-
-      <method name="_mirror">
-        <body>
-          if (this.hasAttribute("mirror"))
-            this.removeAttribute("mirror");
-          else
-            this.setAttribute("mirror", "true");
-
-          if (!this.hasAttribute("sizelimit")) {
-            this.setAttribute("sizelimit", "true");
-            this._calcMouseTargetRect();
-          }
-        </body>
-      </method>
-    </implementation>
-  </binding>
-
-</bindings>