diff --git a/browser/base/content/browser.js b/browser/base/content/browser.js
index 3b3b3937010..be24637649c 100644
--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -7198,7 +7198,6 @@ let gPrivateBrowsingUI = {
     // temporary fix until bug 463607 is fixed
     document.getElementById("Tools:Sanitize").setAttribute("disabled", "true");
 
-    // Adjust the window's title
     if (window.location.href == getBrowserURL()) {
 #ifdef XP_MACOSX
       if (!PrivateBrowsingUtils.permanentPrivateBrowsing) {
@@ -7206,6 +7205,7 @@ let gPrivateBrowsingUI = {
       }
 #endif
 
+      // Adjust the window's title
       let docElement = document.documentElement;
       docElement.setAttribute("title",
         docElement.getAttribute("title_privatebrowsing"));
@@ -7214,6 +7214,23 @@ let gPrivateBrowsingUI = {
       docElement.setAttribute("privatebrowsingmode",
         PrivateBrowsingUtils.permanentPrivateBrowsing ? "permanent" : "temporary");
       gBrowser.updateTitlebar();
+
+      if (PrivateBrowsingUtils.permanentPrivateBrowsing) {
+        // Adjust the New Window menu entries
+        [
+          { normal: "menu_newNavigator", private: "menu_newPrivateWindow" },
+          { normal: "appmenu_newNavigator", private: "appmenu_newPrivateWindow" },
+        ].forEach(function(menu) {
+          let newWindow = document.getElementById(menu.normal);
+          let newPrivateWindow = document.getElementById(menu.private);
+          if (newWindow && newPrivateWindow) {
+            newPrivateWindow.hidden = true;
+            newWindow.label = newPrivateWindow.label;
+            newWindow.accessKey = newPrivateWindow.accessKey;
+            newWindow.command = newPrivateWindow.command;
+          }
+        });
+      }
     }
 
     if (gURLBar) {
diff --git a/browser/base/content/test/browser_private_browsing_window.js b/browser/base/content/test/browser_private_browsing_window.js
index d71f98e27f5..49b030a660d 100644
--- a/browser/base/content/test/browser_private_browsing_window.js
+++ b/browser/base/content/test/browser_private_browsing_window.js
@@ -16,9 +16,46 @@ function test() {
   whenDelayedStartupFinished(privateWin, function() {
     nonPrivateWin = privateWin.OpenBrowserWindow({private: false});
     ok(!PrivateBrowsingUtils.isWindowPrivate(nonPrivateWin), "privateWin.OpenBrowserWindow({private: false}) should open a normal window");
+
     nonPrivateWin.close();
+
+    [
+      { normal: "menu_newNavigator", private: "menu_newPrivateWindow" },
+      { normal: "appmenu_newNavigator", private: "appmenu_newPrivateWindow" },
+    ].forEach(function(menu) {
+      let newWindow = privateWin.document.getElementById(menu.normal);
+      let newPrivateWindow = privateWin.document.getElementById(menu.private);
+      if (newWindow && newPrivateWindow) {
+        ok(!newPrivateWindow.hidden, "New Private Window menu item should be hidden");
+        isnot(newWindow.label, newPrivateWindow.label, "New Window's label shouldn't be overwritten");
+        isnot(newWindow.accessKey, newPrivateWindow.accessKey, "New Window's accessKey shouldn't be overwritten");
+        isnot(newWindow.command, newPrivateWindow.command, "New Window's command shouldn't be overwritten");
+      }
+    });
+
     privateWin.close();
-    finish();
+
+    Services.prefs.setBoolPref("browser.privatebrowsing.autostart", true);
+    privateWin = OpenBrowserWindow({private: true});
+    whenDelayedStartupFinished(privateWin, function() {
+      [
+        { normal: "menu_newNavigator", private: "menu_newPrivateWindow" },
+        { normal: "appmenu_newNavigator", private: "appmenu_newPrivateWindow" },
+      ].forEach(function(menu) {
+        let newWindow = privateWin.document.getElementById(menu.normal);
+        let newPrivateWindow = privateWin.document.getElementById(menu.private);
+        if (newWindow && newPrivateWindow) {
+          ok(newPrivateWindow.hidden, "New Private Window menu item should be hidden");
+          is(newWindow.label, newPrivateWindow.label, "New Window's label should be overwritten");
+          is(newWindow.accessKey, newPrivateWindow.accessKey, "New Window's accessKey should be overwritten");
+          is(newWindow.command, newPrivateWindow.command, "New Window's command should be overwritten");
+        }
+      });
+
+      privateWin.close();
+      Services.prefs.clearUserPref("browser.privatebrowsing.autostart");
+      finish();
+    });
   });
 }