--- a/browser/base/content/tabbrowser.js
+++ b/browser/base/content/tabbrowser.js
@@ -1333,17 +1333,17 @@ window._gBrowser = {
             title = title.substring(0, 500) + "\u2026";
           } else {
             var characterSet = browser.characterSet;
             title = Services.textToSubURI.unEscapeNonAsciiURI(characterSet, title);
           }
         } catch (ex) { /* Do nothing. */ }
       } else {
         // Still no title? Fall back to our untitled string.
-        title = gTabBrowserBundle.GetStringFromName("tabs.emptyTabTitle");
+        title = this.tabContainer.emptyTabTitle;
       }
     }
 
     return this._setTabLabel(aTab, title, { isContentTitle });
   },
 
   _setTabLabel(aTab, aLabel, aOptions) {
     if (!aLabel) {
@@ -2265,17 +2265,17 @@ window._gBrowser = {
       lazyBrowserURI = aURIObject;
       aURI = "about:blank";
     }
 
     var uriIsAboutBlank = aURI == "about:blank";
 
     if (!aNoInitialLabel) {
       if (isBlankPageURL(aURI)) {
-        t.setAttribute("label", gTabBrowserBundle.GetStringFromName("tabs.emptyTabTitle"));
+        t.setAttribute("label", this.tabContainer.emptyTabTitle);
       } else {
         // Set URL as label so that the tab isn't empty initially.
         this.setInitialTabTitle(t, aURI, { beforeTabOpen: true });
       }
     }
 
     // Related tab inherits current tab's user context unless a different
     // usercontextid is specified

--- a/browser/base/content/tabbrowser.xml
+++ b/browser/base/content/tabbrowser.xml
@@ -110,18 +110,22 @@
     <implementation implements="nsIDOMEventListener, nsIObserver">
       <constructor>
         <![CDATA[
           this._tabClipWidth = Services.prefs.getIntPref("browser.tabs.tabClipWidth");
 
           let { restoreTabsButton } = this;
           restoreTabsButton.setAttribute("label", gTabBrowserBundle.GetStringFromName("tabs.restoreLastTabs"));
 
+          let strId = PrivateBrowsingUtils.isWindowPrivate(window) ?
+              "emptyPrivateTabTitle" : "emptyTabTitle";
+          this.emptyTabTitle = gTabBrowserBundle.GetStringFromName("tabs." + strId);
+
           var tab = this.firstChild;
-          tab.label = gTabBrowserBundle.GetStringFromName("tabs.emptyTabTitle");
+          tab.label = this.emptyTabTitle;
           tab.setAttribute("onerror", "this.removeAttribute('image');");
 
           window.addEventListener("resize", this);
           window.addEventListener("DOMContentLoaded", this);
 
           Services.prefs.addObserver("privacy.userContext", this);
           this.observe(null, "nsPref:changed", "privacy.userContext.enabled");
 

--- a/browser/components/privatebrowsing/content/aboutPrivateBrowsing.js
+++ b/browser/components/privatebrowsing/content/aboutPrivateBrowsing.js
@@ -28,25 +28,24 @@ function updateTPInfo() {
   tpSubHeader.classList.toggle("tp-off", !trackingEnabled);
 }
 
 document.addEventListener("DOMContentLoaded", function() {
   let aboutCapabilities = document.aboutCapabilities;
   if (!aboutCapabilities.isWindowPrivate()) {
     document.documentElement.classList.remove("private");
     document.documentElement.classList.add("normal");
-    document.title = aboutCapabilities.getStringFromBundle(STRING_BUNDLE, "title.normal");
+    document.title = document.querySelector("title").getAttribute("notprivatetitle");
     document.getElementById("favicon").setAttribute("href", FAVICON_QUESTION);
     document.getElementById("startPrivateBrowsing").addEventListener("click", function() {
       aboutCapabilities.sendAsyncMessage("OpenPrivateWindow", null);
     });
     return;
   }
 
-  document.title = aboutCapabilities.getStringFromBundle(STRING_BUNDLE, "title.head");
   document.getElementById("startTour").addEventListener("click", function() {
     aboutCapabilities.sendAsyncMessage("DontShowIntroPanelAgain", null);
   });
   document.getElementById("startTour").setAttribute("href",
     aboutCapabilities.formatURLPref("privacy.trackingprotection.introURL"));
   document.getElementById("learnMore").setAttribute("href",
     aboutCapabilities.formatURLPref("app.support.baseURL") + "private-browsing");
 

--- a/browser/components/privatebrowsing/content/aboutPrivateBrowsing.xhtml
+++ b/browser/components/privatebrowsing/content/aboutPrivateBrowsing.xhtml
@@ -18,16 +18,17 @@
 ]>
 
 <html xmlns="http://www.w3.org/1999/xhtml" class="private">
   <head>
     <meta http-equiv="Content-Security-Policy" content="default-src chrome:"/>
     <link id="favicon" rel="icon" type="image/png" href="chrome://browser/skin/privatebrowsing/favicon.svg"/>
     <link rel="stylesheet" href="chrome://browser/content/aboutPrivateBrowsing.css" type="text/css" media="all"/>
     <link rel="stylesheet" href="chrome://browser/skin/privatebrowsing/aboutPrivateBrowsing.css" type="text/css" media="all"/>
+    <title notprivatetitle="&aboutPrivateBrowsing.notPrivate.title;">&aboutPrivateBrowsing.title;</title>
     <script type="application/javascript" src="chrome://browser/content/aboutPrivateBrowsing.js"></script>
   </head>
 
   <body dir="&locale.dir;">
     <p class="showNormal">&aboutPrivateBrowsing.notPrivate;</p>
     <button id="startPrivateBrowsing"
             class="showNormal"
             accesskey="&privatebrowsingpage.openPrivateWindow.accesskey;">&privatebrowsingpage.openPrivateWindow.label;</button>

--- a/browser/locales/en-US/chrome/browser/aboutPrivateBrowsing.dtd
+++ b/browser/locales/en-US/chrome/browser/aboutPrivateBrowsing.dtd
@@ -1,12 +1,17 @@
 <!-- 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/. -->
 
+<!-- LOCALIZATION NOTE (aboutPrivateBrowsing.title):
+     Please ensure this exactly matches tabs.emptyPrivateTabTitle in tabbrowser.properties -->
+<!ENTITY aboutPrivateBrowsing.title                      "Private Browsing">
+<!ENTITY aboutPrivateBrowsing.notPrivate.title           "Open a private window?">
+
 <!ENTITY aboutPrivateBrowsing.notPrivate                 "You are currently not in a private window.">
 <!ENTITY privatebrowsingpage.openPrivateWindow.label     "Open a Private Window">
 <!ENTITY privatebrowsingpage.openPrivateWindow.accesskey "P">
 
 <!ENTITY privateBrowsing.title                           "Private Browsing">
 <!ENTITY privateBrowsing.title.tracking                  "Private Browsing with Tracking Protection">
 <!ENTITY aboutPrivateBrowsing.info.notsaved.before       "When you browse in a Private Window, Firefox ">
 <!ENTITY aboutPrivateBrowsing.info.notsaved.emphasize    "does not save">

deleted file mode 100644
--- a/browser/locales/en-US/chrome/browser/aboutPrivateBrowsing.properties
+++ /dev/null
@@ -1,6 +0,0 @@
-# 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/.
-
-title.head=Private Browsing
-title.normal=Open a private window?

--- a/browser/locales/en-US/chrome/browser/tabbrowser.properties
+++ b/browser/locales/en-US/chrome/browser/tabbrowser.properties
@@ -1,14 +1,17 @@
 # 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/.
 
 tabs.restoreLastTabs=Restore Tabs From Last Time
 tabs.emptyTabTitle=New Tab
+# LOCALIZATION NOTE (tabs.emptyPrivateTabTitle)
+# Please ensure this exactly matches aboutPrivateBrowsing.dtd's window title (aboutPrivateBrowsing.title).
+tabs.emptyPrivateTabTitle=Private Browsing
 tabs.closeTab=Close Tab
 tabs.close=Close
 tabs.closeWarningTitle=Confirm close
 # LOCALIZATION NOTE (tabs.closeWarningMultiple):
 # Semicolon-separated list of plural forms. See:
 # http://developer.mozilla.org/en/docs/Localization_and_Plurals
 # The singular form is not considered since this string is used only for
 # multiple tabs.

--- a/browser/locales/jar.mn
+++ b/browser/locales/jar.mn
@@ -10,17 +10,16 @@
 [localization] @AB_CD@.jar:
   browser                                          (%browser/**/*.ftl)
 
 @AB_CD@.jar:
 % locale browser @AB_CD@ %locale/browser/
 *   locale/browser/bookmarks.html                  (generic/profile/bookmarks.html.in)
     locale/browser/aboutDialog.dtd                 (%chrome/browser/aboutDialog.dtd)
     locale/browser/aboutPrivateBrowsing.dtd        (%chrome/browser/aboutPrivateBrowsing.dtd)
-    locale/browser/aboutPrivateBrowsing.properties (%chrome/browser/aboutPrivateBrowsing.properties)
     locale/browser/aboutRobots.dtd                 (%chrome/browser/aboutRobots.dtd)
     locale/browser/aboutHome.dtd                   (%chrome/browser/aboutHome.dtd)
     locale/browser/accounts.properties             (%chrome/browser/accounts.properties)
     locale/browser/aboutSearchReset.dtd            (%chrome/browser/aboutSearchReset.dtd)
     locale/browser/aboutSessionRestore.dtd         (%chrome/browser/aboutSessionRestore.dtd)
     locale/browser/aboutTabCrashed.dtd             (%chrome/browser/aboutTabCrashed.dtd)
     locale/browser/browser.dtd                     (%chrome/browser/browser.dtd)
     locale/browser/baseMenuOverlay.dtd             (%chrome/browser/baseMenuOverlay.dtd)