Add Pale Moon

1 files changed, 607 insertions, 0 deletions

diff --git a/application/palemoon/base/content/browser-fullScreen.js b/application/palemoon/base/content/browser-fullScreen.js
new file mode 100644
index 000000000..b8a29199e
--- /dev/null
+++ b/application/palemoon/base/content/browser-fullScreen.js
@@ -0,0 +1,607 @@
+# -*- Mode: javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+var FullScreen = {
+  _XULNS: "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul",
+  get _fullScrToggler() {
+    delete this._fullScrToggler;
+    return this._fullScrToggler = document.getElementById("fullscr-toggler");
+  },
+  toggle: function (event) {
+    var enterFS = window.fullScreen;
+
+    // We get the fullscreen event _before_ the window transitions into or out of FS mode.
+    if (event && event.type == "fullscreen")
+      enterFS = !enterFS;
+
+    // Toggle the View:FullScreen command, which controls elements like the
+    // fullscreen menuitem, menubars, and the appmenu.
+    let fullscreenCommand = document.getElementById("View:FullScreen");
+    if (enterFS) {
+      fullscreenCommand.setAttribute("checked", enterFS);
+    } else {
+      fullscreenCommand.removeAttribute("checked");
+    }
+
+#ifdef XP_MACOSX
+    // Make sure the menu items are adjusted.
+    document.getElementById("enterFullScreenItem").hidden = enterFS;
+    document.getElementById("exitFullScreenItem").hidden = !enterFS;
+#endif
+
+    // On OS X Lion we don't want to hide toolbars when entering fullscreen, unless
+    // we're entering DOM fullscreen, in which case we should hide the toolbars.
+    // If we're leaving fullscreen, then we'll go through the exit code below to
+    // make sure toolbars are made visible in the case of DOM fullscreen.
+    if (enterFS && this.useLionFullScreen) {
+      if (document.mozFullScreen) {
+        this.showXULChrome("toolbar", false);
+      }
+      else {
+        gNavToolbox.setAttribute("inFullscreen", true);
+        document.documentElement.setAttribute("inFullscreen", true);
+      }
+      return;
+    }
+
+    // show/hide menubars, toolbars (except the full screen toolbar)
+    this.showXULChrome("toolbar", !enterFS);
+
+    if (enterFS) {
+      // Add a tiny toolbar to receive mouseover and dragenter events, and provide affordance.
+      // This will help simulate the "collapse" metaphor while also requiring less code and
+      // events than raw listening of mouse coords. We don't add the toolbar in DOM full-screen
+      // mode, only browser full-screen mode.
+      if (!document.mozFullScreen) {
+        this._fullScrToggler.addEventListener("mouseover", this._expandCallback, false);
+        this._fullScrToggler.addEventListener("dragenter", this._expandCallback, false);
+      }
+      if (gPrefService.getBoolPref("browser.fullscreen.autohide"))
+        gBrowser.mPanelContainer.addEventListener("mousemove",
+                                                  this._collapseCallback, false);
+
+      document.addEventListener("keypress", this._keyToggleCallback, false);
+      document.addEventListener("popupshown", this._setPopupOpen, false);
+      document.addEventListener("popuphidden", this._setPopupOpen, false);
+      // We don't animate the toolbar collapse if in DOM full-screen mode,
+      // as the size of the content area would still be changing after the
+      // mozfullscreenchange event fired, which could confuse content script.
+      this._shouldAnimate = !document.mozFullScreen;
+      this.mouseoverToggle(false);
+
+      // Autohide prefs
+      gPrefService.addObserver("browser.fullscreen", this, false);
+    }
+    else {
+      // The user may quit fullscreen during an animation
+      this._cancelAnimation();
+      gNavToolbox.style.marginTop = "";
+      if (this._isChromeCollapsed)
+        this.mouseoverToggle(true);
+      // This is needed if they use the context menu to quit fullscreen
+      this._isPopupOpen = false;
+
+      document.documentElement.removeAttribute("inDOMFullscreen");
+
+      this.cleanup();
+    }
+  },
+
+  exitDomFullScreen : function() {
+    document.mozCancelFullScreen();
+  },
+
+  handleEvent: function (event) {
+    switch (event.type) {
+      case "activate":
+        if (document.mozFullScreen) {
+          this.showWarning(this.fullscreenDoc);
+        }
+        break;
+      case "transitionend":
+        if (event.propertyName == "opacity")
+          this.cancelWarning();
+        break;
+    }
+  },
+
+  enterDomFullscreen : function(event) {
+    if (!document.mozFullScreen)
+      return;
+
+    // However, if we receive a "MozEnteredDomFullScreen" event for a document
+    // which is not a subdocument of a currently active (ie. visible) browser
+    // or iframe, we know that we've switched to a different frame since the
+    // request to enter full-screen was made, so we should exit full-screen
+    // since the "full-screen document" isn't acutally visible.
+    if (!event.target.defaultView.QueryInterface(Ci.nsIInterfaceRequestor)
+                                 .getInterface(Ci.nsIWebNavigation)
+                                 .QueryInterface(Ci.nsIDocShell).isActive) {
+      document.mozCancelFullScreen();
+      return;
+    }
+
+    let focusManager = Cc["@mozilla.org/focus-manager;1"].getService(Ci.nsIFocusManager);
+    if (focusManager.activeWindow != window) {
+      // The top-level window has lost focus since the request to enter
+      // full-screen was made. Cancel full-screen.
+      document.mozCancelFullScreen();
+      return;
+    }
+
+    document.documentElement.setAttribute("inDOMFullscreen", true);
+
+    if (gFindBarInitialized)
+      gFindBar.close();
+
+    this.showWarning(event.target);
+
+    // Exit DOM full-screen mode upon open, close, or change tab.
+    gBrowser.tabContainer.addEventListener("TabOpen", this.exitDomFullScreen);
+    gBrowser.tabContainer.addEventListener("TabClose", this.exitDomFullScreen);
+    gBrowser.tabContainer.addEventListener("TabSelect", this.exitDomFullScreen);
+
+    // Add listener to detect when the fullscreen window is re-focused.
+    // If a fullscreen window loses focus, we show a warning when the
+    // fullscreen window is refocused.
+    if (!this.useLionFullScreen) {
+      window.addEventListener("activate", this);
+    }
+
+    // Cancel any "hide the toolbar" animation which is in progress, and make
+    // the toolbar hide immediately.
+    this._cancelAnimation();
+    this.mouseoverToggle(false);
+
+    // Remove listeners on the full-screen toggler, so that mouseover
+    // the top of the screen will not cause the toolbar to re-appear.
+    this._fullScrToggler.removeEventListener("mouseover", this._expandCallback, false);
+    this._fullScrToggler.removeEventListener("dragenter", this._expandCallback, false);
+  },
+
+  cleanup: function () {
+    if (window.fullScreen) {
+      gBrowser.mPanelContainer.removeEventListener("mousemove",
+                                                   this._collapseCallback, false);
+      document.removeEventListener("keypress", this._keyToggleCallback, false);
+      document.removeEventListener("popupshown", this._setPopupOpen, false);
+      document.removeEventListener("popuphidden", this._setPopupOpen, false);
+      gPrefService.removeObserver("browser.fullscreen", this);
+
+      this._fullScrToggler.removeEventListener("mouseover", this._expandCallback, false);
+      this._fullScrToggler.removeEventListener("dragenter", this._expandCallback, false);
+      this.cancelWarning();
+      gBrowser.tabContainer.removeEventListener("TabOpen", this.exitDomFullScreen);
+      gBrowser.tabContainer.removeEventListener("TabClose", this.exitDomFullScreen);
+      gBrowser.tabContainer.removeEventListener("TabSelect", this.exitDomFullScreen);
+      if (!this.useLionFullScreen)
+        window.removeEventListener("activate", this);
+      this.fullscreenDoc = null;
+    }
+  },
+
+  observe: function(aSubject, aTopic, aData)
+  {
+    if (aData == "browser.fullscreen.autohide") {
+      if (gPrefService.getBoolPref("browser.fullscreen.autohide")) {
+        gBrowser.mPanelContainer.addEventListener("mousemove",
+                                                  this._collapseCallback, false);
+      }
+      else {
+        gBrowser.mPanelContainer.removeEventListener("mousemove",
+                                                     this._collapseCallback, false);
+      }
+    }
+  },
+
+  // Event callbacks
+  _expandCallback: function()
+  {
+    FullScreen.mouseoverToggle(true);
+  },
+  _collapseCallback: function()
+  {
+    FullScreen.mouseoverToggle(false);
+  },
+  _keyToggleCallback: function(aEvent)
+  {
+    // if we can use the keyboard (eg Ctrl+L or Ctrl+E) to open the toolbars, we
+    // should provide a way to collapse them too.
+    if (aEvent.keyCode == aEvent.DOM_VK_ESCAPE) {
+      FullScreen._shouldAnimate = false;
+      FullScreen.mouseoverToggle(false, true);
+    }
+    // F6 is another shortcut to the address bar, but its not covered in OpenLocation()
+    else if (aEvent.keyCode == aEvent.DOM_VK_F6)
+      FullScreen.mouseoverToggle(true);
+  },
+
+  // Checks whether we are allowed to collapse the chrome
+  _isPopupOpen: false,
+  _isChromeCollapsed: false,
+  _safeToCollapse: function(forceHide)
+  {
+    if (!gPrefService.getBoolPref("browser.fullscreen.autohide"))
+      return false;
+
+    // a popup menu is open in chrome: don't collapse chrome
+    if (!forceHide && this._isPopupOpen)
+      return false;
+
+    // a textbox in chrome is focused (location bar anyone?): don't collapse chrome
+    if (document.commandDispatcher.focusedElement &&
+        document.commandDispatcher.focusedElement.ownerDocument == document &&
+        document.commandDispatcher.focusedElement.localName == "input") {
+      if (forceHide)
+        // hidden textboxes that still have focus are bad bad bad
+        document.commandDispatcher.focusedElement.blur();
+      else
+        return false;
+    }
+    return true;
+  },
+
+  _setPopupOpen: function(aEvent)
+  {
+    // Popups should only veto chrome collapsing if they were opened when the chrome was not collapsed.
+    // Otherwise, they would not affect chrome and the user would expect the chrome to go away.
+    // e.g. we wouldn't want the autoscroll icon firing this event, so when the user
+    // toggles chrome when moving mouse to the top, it doesn't go away again.
+    if (aEvent.type == "popupshown" && !FullScreen._isChromeCollapsed &&
+        aEvent.target.localName != "tooltip" && aEvent.target.localName != "window")
+      FullScreen._isPopupOpen = true;
+    else if (aEvent.type == "popuphidden" && aEvent.target.localName != "tooltip" &&
+             aEvent.target.localName != "window")
+      FullScreen._isPopupOpen = false;
+  },
+
+  // Autohide helpers for the context menu item
+  getAutohide: function(aItem)
+  {
+    aItem.setAttribute("checked", gPrefService.getBoolPref("browser.fullscreen.autohide"));
+  },
+  setAutohide: function()
+  {
+    gPrefService.setBoolPref("browser.fullscreen.autohide", !gPrefService.getBoolPref("browser.fullscreen.autohide"));
+  },
+
+  // Animate the toolbars disappearing
+  _shouldAnimate: true,
+  _isAnimating: false,
+  _animationTimeout: 0,
+  _animationHandle: 0,
+  _animateUp: function() {
+    // check again, the user may have done something before the animation was due to start
+    if (!window.fullScreen || !this._safeToCollapse(false)) {
+      this._isAnimating = false;
+      this._shouldAnimate = true;
+      return;
+    }
+
+    this._animateStartTime = window.mozAnimationStartTime;
+    if (!this._animationHandle)
+      this._animationHandle = window.mozRequestAnimationFrame(this);
+  },
+
+  sample: function (timeStamp) {
+    const duration = 1500;
+    const timePassed = timeStamp - this._animateStartTime;
+    const pos = timePassed >= duration ? 1 :
+                1 - Math.pow(1 - timePassed / duration, 4);
+
+    if (pos >= 1) {
+      // We've animated enough
+      this._cancelAnimation();
+      gNavToolbox.style.marginTop = "";
+      this.mouseoverToggle(false);
+      return;
+    }
+
+    gNavToolbox.style.marginTop = (gNavToolbox.boxObject.height * pos * -1) + "px";
+    this._animationHandle = window.mozRequestAnimationFrame(this);
+  },
+
+  _cancelAnimation: function() {
+    window.mozCancelAnimationFrame(this._animationHandle);
+    this._animationHandle = 0;
+    clearTimeout(this._animationTimeout);
+    this._isAnimating = false;
+    this._shouldAnimate = false;
+  },
+
+  cancelWarning: function(event) {
+    if (!this.warningBox)
+      return;
+    this.warningBox.removeEventListener("transitionend", this);
+    if (this.warningFadeOutTimeout) {
+      clearTimeout(this.warningFadeOutTimeout);
+      this.warningFadeOutTimeout = null;
+    }
+
+    // Ensure focus switches away from the (now hidden) warning box. If the user
+    // clicked buttons in the fullscreen key authorization UI, it would have been
+    // focused, and any key events would be directed at the (now hidden) chrome
+    // document instead of the target document.
+    gBrowser.selectedBrowser.focus();
+
+    this.warningBox.setAttribute("hidden", true);
+    this.warningBox.removeAttribute("fade-warning-out");
+    this.warningBox.removeAttribute("obscure-browser");
+    this.warningBox = null;
+  },
+
+  setFullscreenAllowed: function(isApproved) {
+    // The "remember decision" checkbox is hidden when showing for documents that
+    // the permission manager can't handle (documents with URIs without a host).
+    // We simply require those to be approved every time instead.
+    let rememberCheckbox = document.getElementById("full-screen-remember-decision");
+    let uri = this.fullscreenDoc.nodePrincipal.URI;
+    if (!rememberCheckbox.hidden) {
+      if (rememberCheckbox.checked)
+        Services.perms.add(uri,
+                           "fullscreen",
+                           isApproved ? Services.perms.ALLOW_ACTION : Services.perms.DENY_ACTION,
+                           Services.perms.EXPIRE_NEVER);
+      else if (isApproved) {
+        // The user has only temporarily approved fullscren for this fullscreen
+        // session only. Add the permission (so Goanna knows to approve any further
+        // fullscreen requests for this host in this fullscreen session) but add
+        // a listener to revoke the permission when the chrome document exits
+        // fullscreen.
+        Services.perms.add(uri,
+                           "fullscreen",
+                           Services.perms.ALLOW_ACTION,
+                           Services.perms.EXPIRE_SESSION);
+        let host = uri.host;
+        var onFullscreenchange = function onFullscreenchange(event) {
+          if (event.target == document && document.mozFullScreenElement == null) {
+            // The chrome document has left fullscreen. Remove the temporary permission grant.
+            Services.perms.remove(host, "fullscreen");
+            document.removeEventListener("mozfullscreenchange", onFullscreenchange);
+          }
+        }
+        document.addEventListener("mozfullscreenchange", onFullscreenchange);
+      }
+    }
+    if (this.warningBox)
+      this.warningBox.setAttribute("fade-warning-out", "true");
+    // If the document has been granted fullscreen, notify Goanna so it can resume
+    // any pending pointer lock requests, otherwise exit fullscreen; the user denied
+    // the fullscreen request.
+    if (isApproved)
+      Services.obs.notifyObservers(this.fullscreenDoc, "fullscreen-approved", "");
+    else
+      document.mozCancelFullScreen();
+  },
+
+  warningBox: null,
+  warningFadeOutTimeout: null,
+  fullscreenDoc: null,
+
+  // Shows the fullscreen approval UI, or if the domain has already been approved
+  // for fullscreen, shows a warning that the site has entered fullscreen for a short
+  // duration.
+  showWarning: function(targetDoc) {
+    if (!document.mozFullScreen ||
+        !gPrefService.getBoolPref("full-screen-api.approval-required"))
+      return;
+
+    // Set the strings on the fullscreen approval UI.
+    this.fullscreenDoc = targetDoc;
+    let uri = this.fullscreenDoc.nodePrincipal.URI;
+    let host = null;
+    try {
+      host = uri.host;
+    } catch (e) { }
+    let hostLabel = document.getElementById("full-screen-domain-text");
+    let rememberCheckbox = document.getElementById("full-screen-remember-decision");
+    let isApproved = false;
+    if (host) {
+      // Document's principal's URI has a host. Display a warning including the hostname and
+      // show UI to enable the user to permanently grant this host permission to enter fullscreen.
+      let utils = {};
+      Cu.import("resource://gre/modules/DownloadUtils.jsm", utils);
+      let displayHost = utils.DownloadUtils.getURIHost(uri.spec)[0];
+      let bundle = Services.strings.createBundle("chrome://browser/locale/browser.properties");
+
+      hostLabel.textContent = bundle.formatStringFromName("fullscreen.entered", [displayHost], 1);
+      hostLabel.removeAttribute("hidden");
+
+      rememberCheckbox.label = bundle.formatStringFromName("fullscreen.rememberDecision", [displayHost], 1);
+      rememberCheckbox.checked = false;
+      rememberCheckbox.removeAttribute("hidden");
+
+      // Note we only allow documents whose principal's URI has a host to
+      // store permission grants.
+      isApproved = Services.perms.testPermission(uri, "fullscreen") == Services.perms.ALLOW_ACTION;
+    } else {
+      hostLabel.setAttribute("hidden", "true");
+      rememberCheckbox.setAttribute("hidden", "true");
+    }
+
+    // Note: the warning box can be non-null if the warning box from the previous request
+    // wasn't hidden before another request was made.
+    if (!this.warningBox) {
+      this.warningBox = document.getElementById("full-screen-warning-container");
+      // Add a listener to clean up state after the warning is hidden.
+      this.warningBox.addEventListener("transitionend", this);
+      this.warningBox.removeAttribute("hidden");
+    } else {
+      if (this.warningFadeOutTimeout) {
+        clearTimeout(this.warningFadeOutTimeout);
+        this.warningFadeOutTimeout = null;
+      }
+      this.warningBox.removeAttribute("fade-warning-out");
+    }
+
+    // If fullscreen mode has not yet been approved for the fullscreen
+    // document's domain, show the approval UI and don't auto fade out the
+    // fullscreen warning box. Otherwise, we're just notifying of entry into
+    // fullscreen mode. Note if the resource's host is null, we must be
+    // showing a local file or a local data URI, and we require explicit
+    // approval every time.
+    let authUI = document.getElementById("full-screen-approval-pane");
+    if (isApproved) {
+      authUI.setAttribute("hidden", "true");
+      this.warningBox.removeAttribute("obscure-browser");
+    } else {
+      // Partially obscure the <browser> element underneath the approval UI.
+      this.warningBox.setAttribute("obscure-browser", "true");
+      authUI.removeAttribute("hidden");
+    }
+
+    // If we're not showing the fullscreen approval UI, we're just notifying the user
+    // of the transition, so set a timeout to fade the warning out after a few moments.
+    if (isApproved)
+      this.warningFadeOutTimeout =
+        setTimeout(
+          function() {
+            if (this.warningBox)
+              this.warningBox.setAttribute("fade-warning-out", "true");
+          }.bind(this),
+          3000);
+  },
+
+  mouseoverToggle: function(aShow, forceHide)
+  {
+    // Don't do anything if:
+    // a) we're already in the state we want,
+    // b) we're animating and will become collapsed soon, or
+    // c) we can't collapse because it would be undesirable right now
+    if (aShow != this._isChromeCollapsed || (!aShow && this._isAnimating) ||
+        (!aShow && !this._safeToCollapse(forceHide)))
+      return;
+
+    // browser.fullscreen.animateUp
+    // 0 - never animate up
+    // 1 - animate only for first collapse after entering fullscreen (default for perf's sake)
+    // 2 - animate every time it collapses
+    if (gPrefService.getIntPref("browser.fullscreen.animateUp") == 0)
+      this._shouldAnimate = false;
+
+    if (!aShow && this._shouldAnimate) {
+      this._isAnimating = true;
+      this._shouldAnimate = false;
+      this._animationTimeout = setTimeout(this._animateUp.bind(this), 800);
+      return;
+    }
+
+    // The chrome is collapsed so don't spam needless mousemove events
+    if (aShow) {
+      gBrowser.mPanelContainer.addEventListener("mousemove",
+                                                this._collapseCallback, false);
+    }
+    else {
+      gBrowser.mPanelContainer.removeEventListener("mousemove",
+                                                   this._collapseCallback, false);
+    }
+
+    // Hiding/collapsing the toolbox interferes with the tab bar's scrollbox,
+    // so we just move it off-screen instead. See bug 430687.
+    gNavToolbox.style.marginTop =
+      aShow ? "" : -gNavToolbox.getBoundingClientRect().height + "px";
+
+    this._fullScrToggler.collapsed = aShow;
+    this._isChromeCollapsed = !aShow;
+    if (gPrefService.getIntPref("browser.fullscreen.animateUp") == 2)
+      this._shouldAnimate = true;
+  },
+
+  showXULChrome: function(aTag, aShow)
+  {
+    var els = document.getElementsByTagNameNS(this._XULNS, aTag);
+
+    for (let el of els) {
+      // XXX don't interfere with previously collapsed toolbars
+      if (el.getAttribute("fullscreentoolbar") == "true") {
+        if (!aShow) {
+
+          var toolbarMode = el.getAttribute("mode");
+          if (toolbarMode != "text") {
+            el.setAttribute("saved-mode", toolbarMode);
+            el.setAttribute("saved-iconsize", el.getAttribute("iconsize"));
+            el.setAttribute("mode", "icons");
+            el.setAttribute("iconsize", "small");
+          }
+
+          // Give the main nav bar and the tab bar the fullscreen context menu,
+          // otherwise remove context menu to prevent breakage
+          el.setAttribute("saved-context", el.getAttribute("context"));
+          if (el.id == "nav-bar" || el.id == "TabsToolbar")
+            el.setAttribute("context", "autohide-context");
+          else
+            el.removeAttribute("context");
+
+          // Set the inFullscreen attribute to allow specific styling
+          // in fullscreen mode
+          el.setAttribute("inFullscreen", true);
+        }
+        else {
+          var restoreAttr = function restoreAttr(attrName) {
+            var savedAttr = "saved-" + attrName;
+            if (el.hasAttribute(savedAttr)) {
+              el.setAttribute(attrName, el.getAttribute(savedAttr));
+              el.removeAttribute(savedAttr);
+            }
+          }
+
+          restoreAttr("mode");
+          restoreAttr("iconsize");
+          restoreAttr("context");
+
+          el.removeAttribute("inFullscreen");
+        }
+      } else {
+        // use moz-collapsed so it doesn't persist hidden/collapsed,
+        // so that new windows don't have missing toolbars
+        if (aShow)
+          el.removeAttribute("moz-collapsed");
+        else
+          el.setAttribute("moz-collapsed", "true");
+      }
+    }
+
+    if (aShow) {
+      gNavToolbox.removeAttribute("inFullscreen");
+      document.documentElement.removeAttribute("inFullscreen");
+    } else {
+      gNavToolbox.setAttribute("inFullscreen", true);
+      document.documentElement.setAttribute("inFullscreen", true);
+    }
+
+    // In tabs-on-top mode, move window controls to the tab bar,
+    // and in tabs-on-bottom mode, move them back to the navigation toolbar.
+    // When there is a chance the tab bar may be collapsed, put window
+    // controls on nav bar.
+    var fullscreenctls = document.getElementById("window-controls");
+    var navbar = document.getElementById("nav-bar");
+    var ctlsOnTabbar = window.toolbar.visible &&
+                        (navbar.collapsed || (TabsOnTop.enabled &&
+                        !gPrefService.getBoolPref("browser.tabs.autoHide")));
+    if (fullscreenctls.parentNode == navbar && ctlsOnTabbar) {
+      fullscreenctls.removeAttribute("flex");
+      document.getElementById("TabsToolbar").appendChild(fullscreenctls);
+    }
+    else if (fullscreenctls.parentNode.id == "TabsToolbar" && !ctlsOnTabbar) {
+      fullscreenctls.setAttribute("flex", "1");
+      navbar.appendChild(fullscreenctls);
+    }
+    fullscreenctls.hidden = aShow;
+    
+    ToolbarIconColor.inferFromText();
+  }
+};
+XPCOMUtils.defineLazyGetter(FullScreen, "useLionFullScreen", function() {
+  // We'll only use OS X Lion full screen if we're
+  // * on OS X
+  // * on Lion or higher (Darwin 11+)
+  // * have fullscreenbutton="true"
+#ifdef XP_MACOSX
+  return parseFloat(Services.sysinfo.getProperty("version")) >= 11 &&
+         document.documentElement.getAttribute("fullscreenbutton") == "true";
+#else
+  return false;
+#endif
+});