[PALEMOON] Wholesale steal Basilisk's shell component

17 files changed, 553 insertions, 424 deletions

diff --git a/application/palemoon/components/shell/Makefile.in b/application/palemoon/components/shell/Makefile.in
deleted file mode 100644
index df084b709..000000000
--- a/application/palemoon/components/shell/Makefile.in
+++ /dev/null
@@ -1,11 +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/.
-
-include $(topsrcdir)/config/rules.mk
-
-CXXFLAGS += $(TK_CFLAGS)
-
-clobber::
-	rm -f $(DIST)/lib/$(LIBRARY_NAME).lib
diff --git a/application/palemoon/components/shell/ShellService.jsm b/application/palemoon/components/shell/ShellService.jsm
new file mode 100644
index 000000000..12e275bdb
--- /dev/null
+++ b/application/palemoon/components/shell/ShellService.jsm
@@ -0,0 +1,114 @@
+/* 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/. */
+
+"use strict";
+
+this.EXPORTED_SYMBOLS = ["ShellService"];
+
+const { classes: Cc, interfaces: Ci, utils: Cu, results: Cr } = Components;
+
+Cu.import("resource://gre/modules/AppConstants.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "WindowsRegistry",
+                                  "resource://gre/modules/WindowsRegistry.jsm");
+
+/**
+ * Internal functionality to save and restore the docShell.allow* properties.
+ */
+let ShellServiceInternal = {
+  /**
+   * Used to determine whether or not to offer "Set as desktop background"
+   * functionality. Even if shell service is available it is not
+   * guaranteed that it is able to set the background for every desktop
+   * which is especially true for Linux with its many different desktop
+   * environments.
+   */
+  get canSetDesktopBackground() {
+    if (AppConstants.platform == "win" ||
+        AppConstants.platform == "macosx") {
+      return true;
+    }
+
+    if (AppConstants.platform == "linux") {
+      if (this.shellService) {
+        let linuxShellService = this.shellService
+                                    .QueryInterface(Ci.nsIGNOMEShellService);
+        return linuxShellService.canSetDesktopBackground;
+      }
+    }
+
+    return false;
+  },
+
+  /**
+   * Used to determine whether or not to show a "Set Default Browser"
+   * query dialog. This attribute is true if the application is starting
+   * up and "browser.shell.checkDefaultBrowser" is true, otherwise it
+   * is false.
+   */
+  _checkedThisSession: false,
+  get shouldCheckDefaultBrowser() {
+    // If we've already checked, the browser has been started and this is a
+    // new window open, and we don't want to check again.
+    if (this._checkedThisSession) {
+      return false;
+    }
+
+    if (!Services.prefs.getBoolPref("browser.shell.checkDefaultBrowser")) {
+      return false;
+    }
+
+    if (AppConstants.platform == "win") {
+      let optOutValue = WindowsRegistry.readRegKey(Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER,
+                                                   "Software\\Mozilla\\PaleMoon",
+                                                   "DefaultBrowserOptOut");
+      WindowsRegistry.removeRegKey(Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER,
+                                   "Software\\Mozilla\\PaleMoon",
+                                   "DefaultBrowserOptOut");
+      if (optOutValue == "True") {
+        Services.prefs.setBoolPref("browser.shell.checkDefaultBrowser", false);
+        return false;
+      }
+    }
+
+    return true;
+  },
+
+  set shouldCheckDefaultBrowser(shouldCheck) {
+    Services.prefs.setBoolPref("browser.shell.checkDefaultBrowser", !!shouldCheck);
+  },
+
+  isDefaultBrowser(startupCheck, forAllTypes) {
+    // If this is the first browser window, maintain internal state that we've
+    // checked this session (so that subsequent window opens don't show the
+    // default browser dialog).
+    if (startupCheck) {
+      this._checkedThisSession = true;
+    }
+    if (this.shellService) {
+      return this.shellService.isDefaultBrowser(startupCheck, forAllTypes);
+    }
+    return false;
+  }
+};
+
+XPCOMUtils.defineLazyServiceGetter(ShellServiceInternal, "shellService",
+  "@mozilla.org/browser/shell-service;1", Ci.nsIShellService);
+
+/**
+ * The external API exported by this module.
+ */
+this.ShellService = new Proxy(ShellServiceInternal, {
+  get(target, name) {
+    if (name in target) {
+      return target[name];
+    }
+    if (target.shellService) {
+      return target.shellService[name];
+    }
+    Services.console.logStringMessage(`${name} not found in ShellService: ${target.shellService}`);
+    return undefined;
+  }
+});
diff --git a/application/palemoon/components/shell/content/setDesktopBackground.js b/application/palemoon/components/shell/content/setDesktopBackground.js
index e90a32d03..53cc70db0 100644
--- a/application/palemoon/components/shell/content/setDesktopBackground.js
+++ b/application/palemoon/components/shell/content/setDesktopBackground.js
@@ -1,16 +1,14 @@
-# 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/.
+/* 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/. */
+
+Components.utils.import("resource://gre/modules/AppConstants.jsm");
 
 var Ci = Components.interfaces;
 
 var gSetBackground = {
-#ifndef XP_MACOSX
-  _position        : "",
-  _backgroundColor : 0,
-#else
-  _position        : "STRETCH",
-#endif
+  _position        : AppConstants.platform == "macosx" ? "STRETCH" : "",
+  _backgroundColor : AppConstants.platform != "macosx" ? 0 : undefined,
   _screenWidth     : 0,
   _screenHeight    : 0,
   _image           : null,
@@ -27,23 +25,23 @@ var gSetBackground = {
     this._canvas = document.getElementById("screen");
     this._screenWidth = screen.width;
     this._screenHeight = screen.height;
-#ifdef XP_MACOSX
-    document.documentElement.getButton("accept").hidden = true;
-#endif
+    if (AppConstants.platform == "macosx") {
+      document.documentElement.getButton("accept").hidden = true;
+    }
     if (this._screenWidth / this._screenHeight >= 1.6)
       document.getElementById("monitor").setAttribute("aspectratio", "16:10");
 
-#ifdef XP_WIN
-    // hide fill + fit options if <win7 since don't work 
-    var version = Components.classes["@mozilla.org/system-info;1"]
-                  .getService(Ci.nsIPropertyBag2)
-                  .getProperty("version");
-    var isWindows7OrHigher = (parseFloat(version) >= 6.1);
-    if (!isWindows7OrHigher) {
-      document.getElementById("fillPosition").hidden = true;
-      document.getElementById("fitPosition").hidden = true;
+    if (AppConstants.platform == "win") {
+      // Hide fill + fit options if < Win7 since they don't work.
+      var version = Components.classes["@mozilla.org/system-info;1"]
+                    .getService(Ci.nsIPropertyBag2)
+                    .getProperty("version");
+      var isWindows7OrHigher = (parseFloat(version) >= 6.1);
+      if (!isWindows7OrHigher) {
+        document.getElementById("fillPosition").hidden = true;
+        document.getElementById("fitPosition").hidden = true;
+      }
     }
-#endif
 
     // make sure that the correct dimensions will be used
     setTimeout(function(self) {
@@ -62,92 +60,37 @@ var gSetBackground = {
     var ctx = this._canvas.getContext("2d");
     ctx.scale(this._canvas.clientWidth / this._screenWidth, this._canvas.clientHeight / this._screenHeight);
 
-#ifndef XP_MACOSX
-    this._initColor();
-#else
-    // Make sure to reset the button state in case the user has already
-    // set an image as their desktop background.
-    var setDesktopBackground = document.getElementById("setDesktopBackground");
-    setDesktopBackground.hidden = false;
-    var bundle = document.getElementById("backgroundBundle");
-    setDesktopBackground.label = bundle.getString("DesktopBackgroundSet");
-    setDesktopBackground.disabled = false;
-
-    document.getElementById("showDesktopPreferences").hidden = true;
-#endif
+    if (AppConstants.platform != "macosx") {
+      this._initColor();
+    } else {
+      // Make sure to reset the button state in case the user has already
+      // set an image as their desktop background.
+      var setDesktopBackground = document.getElementById("setDesktopBackground");
+      setDesktopBackground.hidden = false;
+      var bundle = document.getElementById("backgroundBundle");
+      setDesktopBackground.label = bundle.getString("DesktopBackgroundSet");
+      setDesktopBackground.disabled = false;
+
+      document.getElementById("showDesktopPreferences").hidden = true;
+    }
     this.updatePosition();
   },
 
-#ifndef XP_MACOSX
-  _initColor: function ()
-  {
-    var color = this._shell.desktopBackgroundColor;
-
-    const rMask = 4294901760;
-    const gMask = 65280;
-    const bMask = 255;
-    var r = (color & rMask) >> 16;
-    var g = (color & gMask) >> 8;
-    var b = (color & bMask);
-    this.updateColor(this._rgbToHex(r, g, b));
-
-    var colorpicker = document.getElementById("desktopColor");
-    colorpicker.color = this._backgroundColor;
-  },
-
-  updateColor: function (aColor)
-  {
-    this._backgroundColor = aColor;
-    this._canvas.style.backgroundColor = aColor;
-  },
-
-  // Converts a color string in the format "#RRGGBB" to an integer.
-  _hexStringToLong: function (aString)
-  {
-    return parseInt(aString.substring(1,3), 16) << 16 |
-           parseInt(aString.substring(3,5), 16) << 8 |
-           parseInt(aString.substring(5,7), 16);
-  },
-
-  _rgbToHex: function (aR, aG, aB)
-  {
-    return "#" + [aR, aG, aB].map(function(aInt) aInt.toString(16).replace(/^(.)$/, "0$1"))
-                             .join("").toUpperCase();
-  },
-#else
-  observe: function (aSubject, aTopic, aData)
+  setDesktopBackground: function ()
   {
-    if (aTopic == "shell:desktop-background-changed") {
-      document.getElementById("setDesktopBackground").hidden = true;
-      document.getElementById("showDesktopPreferences").hidden = false;
-
+    if (AppConstants.platform != "macosx") {
+      document.persist("menuPosition", "value");
+      this._shell.desktopBackgroundColor = this._hexStringToLong(this._backgroundColor);
+    } else {
       Components.classes["@mozilla.org/observer-service;1"]
                 .getService(Ci.nsIObserverService)
-                .removeObserver(this, "shell:desktop-background-changed");
-    }
-  },
-
-  showDesktopPrefs: function()
-  {
-    this._shell.openApplication(Ci.nsIMacShellService.APPLICATION_DESKTOP);
-  },
-#endif
+                .addObserver(this, "shell:desktop-background-changed", false);
 
-  setDesktopBackground: function ()
-  {
-#ifndef XP_MACOSX
-    document.persist("menuPosition", "value");
-    this._shell.desktopBackgroundColor = this._hexStringToLong(this._backgroundColor);
-#else
-    Components.classes["@mozilla.org/observer-service;1"]
-              .getService(Ci.nsIObserverService)
-              .addObserver(this, "shell:desktop-background-changed", false);
-
-    var bundle = document.getElementById("backgroundBundle");
-    var setDesktopBackground = document.getElementById("setDesktopBackground");
-    setDesktopBackground.disabled = true;
-    setDesktopBackground.label = bundle.getString("DesktopBackgroundDownloading");
-#endif
+      var bundle = document.getElementById("backgroundBundle");
+      var setDesktopBackground = document.getElementById("setDesktopBackground");
+      setDesktopBackground.disabled = true;
+      setDesktopBackground.label = bundle.getString("DesktopBackgroundDownloading");
+    }
     this._shell.setDesktopBackground(this._image,
                                      Ci.nsIShellService["BACKGROUND_" + this._position]);
   },
@@ -157,9 +100,9 @@ var gSetBackground = {
     var ctx = this._canvas.getContext("2d");
     ctx.clearRect(0, 0, this._screenWidth, this._screenHeight);
 
-#ifndef XP_MACOSX
-    this._position = document.getElementById("menuPosition").value;
-#endif
+    if (AppConstants.platform != "macosx") {
+      this._position = document.getElementById("menuPosition").value;
+    }
 
     switch (this._position) {
       case "TILE":
@@ -171,43 +114,101 @@ var gSetBackground = {
       case "STRETCH":
         ctx.drawImage(this._image, 0, 0, this._screenWidth, this._screenHeight);
         break;
-      case "CENTER":
-        var x = (this._screenWidth - this._image.naturalWidth) / 2;
-        var y = (this._screenHeight - this._image.naturalHeight) / 2;
+      case "CENTER": {
+        let x = (this._screenWidth - this._image.naturalWidth) / 2;
+        let y = (this._screenHeight - this._image.naturalHeight) / 2;
         ctx.drawImage(this._image, x, y);
         break;
-      case "FILL":
-        //Try maxing width first, overflow height
-        var widthRatio = this._screenWidth / this._image.naturalWidth;
-        var width = this._image.naturalWidth * widthRatio;
-        var height = this._image.naturalHeight * widthRatio;
+      }
+      case "FILL": {
+        // Try maxing width first, overflow height.
+        let widthRatio = this._screenWidth / this._image.naturalWidth;
+        let width = this._image.naturalWidth * widthRatio;
+        let height = this._image.naturalHeight * widthRatio;
         if (height < this._screenHeight) {
-          //height less than screen, max height and overflow width
-          var heightRatio = this._screenHeight / this._image.naturalHeight;
+          // Height less than screen, max height and overflow width.
+          let heightRatio = this._screenHeight / this._image.naturalHeight;
           width = this._image.naturalWidth * heightRatio;
           height = this._image.naturalHeight * heightRatio;
         }
-        var x = (this._screenWidth - width) / 2;
-        var y = (this._screenHeight - height) / 2;
+        let x = (this._screenWidth - width) / 2;
+        let y = (this._screenHeight - height) / 2;
         ctx.drawImage(this._image, x, y, width, height);
         break;
-      case "FIT":
-        //Try maxing width first, top and bottom borders
-        var widthRatio = this._screenWidth / this._image.naturalWidth;
-        var width = this._image.naturalWidth * widthRatio;
-        var height = this._image.naturalHeight * widthRatio;
-        var x = 0;
-        var y = (this._screenHeight - height) / 2;
+      }
+      case "FIT": {
+        // Try maxing width first, top and bottom borders.
+        let widthRatio = this._screenWidth / this._image.naturalWidth;
+        let width = this._image.naturalWidth * widthRatio;
+        let height = this._image.naturalHeight * widthRatio;
+        let x = 0;
+        let y = (this._screenHeight - height) / 2;
         if (height > this._screenHeight) {
-          //height overflow, maximise height, side borders
-          var heightRatio = this._screenHeight / this._image.naturalHeight;
+          // Height overflow, maximise height, side borders.
+          let heightRatio = this._screenHeight / this._image.naturalHeight;
           width = this._image.naturalWidth * heightRatio;
           height = this._image.naturalHeight * heightRatio;
           x = (this._screenWidth - width) / 2;
           y = 0;
         }
         ctx.drawImage(this._image, x, y, width, height);
-        break;      
+        break;
+      }
     }
   }
 };
+
+if (AppConstants.platform != "macosx") {
+  gSetBackground["_initColor"] = function ()
+  {
+    var color = this._shell.desktopBackgroundColor;
+
+    const rMask = 4294901760;
+    const gMask = 65280;
+    const bMask = 255;
+    var r = (color & rMask) >> 16;
+    var g = (color & gMask) >> 8;
+    var b = (color & bMask);
+    this.updateColor(this._rgbToHex(r, g, b));
+
+    var colorpicker = document.getElementById("desktopColor");
+    colorpicker.color = this._backgroundColor;
+  };
+
+  gSetBackground["updateColor"] = function (aColor)
+  {
+    this._backgroundColor = aColor;
+    this._canvas.style.backgroundColor = aColor;
+  };
+
+  // Converts a color string in the format "#RRGGBB" to an integer.
+  gSetBackground["_hexStringToLong"] = function (aString)
+  {
+    return parseInt(aString.substring(1, 3), 16) << 16 |
+           parseInt(aString.substring(3, 5), 16) << 8 |
+           parseInt(aString.substring(5, 7), 16);
+  };
+
+  gSetBackground["_rgbToHex"] = function (aR, aG, aB)
+  {
+    return "#" + [aR, aG, aB].map(aInt => aInt.toString(16).replace(/^(.)$/, "0$1"))
+                             .join("").toUpperCase();
+  };
+} else {
+  gSetBackground["observe"] = function (aSubject, aTopic, aData)
+  {
+    if (aTopic == "shell:desktop-background-changed") {
+      document.getElementById("setDesktopBackground").hidden = true;
+      document.getElementById("showDesktopPreferences").hidden = false;
+
+      Components.classes["@mozilla.org/observer-service;1"]
+                .getService(Ci.nsIObserverService)
+                .removeObserver(this, "shell:desktop-background-changed");
+    }
+  };
+
+  gSetBackground["showDesktopPrefs"] = function()
+  {
+    this._shell.openApplication(Ci.nsIMacShellService.APPLICATION_DESKTOP);
+  };
+}
diff --git a/application/palemoon/components/shell/jar.mn b/application/palemoon/components/shell/jar.mn
index eed15c397..1f33b5d56 100644
--- a/application/palemoon/components/shell/jar.mn
+++ b/application/palemoon/components/shell/jar.mn
@@ -4,4 +4,4 @@
 
 browser.jar:
 *       content/browser/setDesktopBackground.xul              (content/setDesktopBackground.xul)
-*       content/browser/setDesktopBackground.js               (content/setDesktopBackground.js)
+        content/browser/setDesktopBackground.js               (content/setDesktopBackground.js)
diff --git a/application/palemoon/components/shell/moz.build b/application/palemoon/components/shell/moz.build
index 38965c5d7..94ec88571 100644
--- a/application/palemoon/components/shell/moz.build
+++ b/application/palemoon/components/shell/moz.build
@@ -1,4 +1,4 @@
-# -*- Mode: python; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*-
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
 # vim: set filetype=python:
 # 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
@@ -18,6 +18,10 @@ elif CONFIG['MOZ_WIDGET_TOOLKIT'] == 'cocoa':
     XPIDL_SOURCES += [
         'nsIMacShellService.idl',
     ]
+elif 'gtk' in CONFIG['MOZ_WIDGET_TOOLKIT']:
+    XPIDL_SOURCES += [
+        'nsIGNOMEShellService.idl',
+    ]
 
 XPIDL_MODULE = 'shellservice'
 
@@ -29,7 +33,7 @@ elif CONFIG['MOZ_WIDGET_TOOLKIT'] == 'cocoa':
     SOURCES += [
         'nsMacShellService.cpp',
     ]
-elif CONFIG['MOZ_WIDGET_GTK']:
+elif 'gtk' in CONFIG['MOZ_WIDGET_TOOLKIT']:
     SOURCES += [
         'nsGNOMEShellService.cpp',
     ]
@@ -42,6 +46,10 @@ EXTRA_COMPONENTS += [
     'nsSetDefaultBrowser.manifest',
 ]
 
+EXTRA_JS_MODULES += [
+    'ShellService.jsm',
+]
+
 for var in ('MOZ_APP_NAME', 'MOZ_APP_VERSION'):
     DEFINES[var] = '"%s"' % CONFIG[var]
 
diff --git a/application/palemoon/components/shell/nsGNOMEShellService.cpp b/application/palemoon/components/shell/nsGNOMEShellService.cpp
index 14510d111..9bc5f5913 100644
--- a/application/palemoon/components/shell/nsGNOMEShellService.cpp
+++ b/application/palemoon/components/shell/nsGNOMEShellService.cpp
@@ -21,12 +21,13 @@
 #include "nsIStringBundle.h"
 #include "nsIOutputStream.h"
 #include "nsIProcess.h"
-#include "nsNetUtil.h"
+#include "nsServiceManagerUtils.h"
+#include "nsComponentManagerUtils.h"
 #include "nsIDOMHTMLImageElement.h"
 #include "nsIImageLoadingContent.h"
 #include "imgIRequest.h"
 #include "imgIContainer.h"
-#include "prprf.h"
+#include "mozilla/Sprintf.h"
 #if defined(MOZ_WIDGET_GTK)
 #include "nsIImageToPixbuf.h"
 #endif
@@ -116,7 +117,7 @@ nsGNOMEShellService::Init()
   return appPath->GetNativePath(mAppPath);
 }
 
-NS_IMPL_ISUPPORTS(nsGNOMEShellService, nsIShellService)
+NS_IMPL_ISUPPORTS(nsGNOMEShellService, nsIGNOMEShellService, nsIShellService)
 
 bool
 nsGNOMEShellService::GetAppPathFromLauncher()
@@ -152,7 +153,8 @@ nsGNOMEShellService::KeyMatchesAppName(const char *aKeyValue) const
 
   gchar *commandPath;
   if (mUseLocaleFilenames) {
-    gchar *nativePath = g_filename_from_utf8(aKeyValue, -1, nullptr, nullptr, nullptr);
+    gchar *nativePath = g_filename_from_utf8(aKeyValue, -1,
+                                             nullptr, nullptr, nullptr);
     if (!nativePath) {
       NS_ERROR("Error converting path to filesystem encoding");
       return false;
@@ -199,8 +201,6 @@ nsGNOMEShellService::IsDefaultBrowser(bool aStartupCheck,
                                       bool* aIsDefaultBrowser)
 {
   *aIsDefaultBrowser = false;
-  if (aStartupCheck)
-    mCheckedThisSession = true;
 
   nsCOMPtr<nsIGConfService> gconf = do_GetService(NS_GCONFSERVICE_CONTRACTID);
   nsCOMPtr<nsIGIOService> giovfs = do_GetService(NS_GIOSERVICE_CONTRACTID);
@@ -284,7 +284,7 @@ nsGNOMEShellService::SetDefaultBrowser(bool aClaimAllTypes,
     NS_ENSURE_SUCCESS(rv, rv);
 
     nsString brandShortName;
-    brandBundle->GetStringFromName(MOZ_UTF16("brandShortName"),
+    brandBundle->GetStringFromName(u"brandShortName",
                                    getter_Copies(brandShortName));
 
     // use brandShortName as the application id.
@@ -312,41 +312,14 @@ nsGNOMEShellService::SetDefaultBrowser(bool aClaimAllTypes,
     }
   }
 
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsGNOMEShellService::GetShouldCheckDefaultBrowser(bool* aResult)
-{
-  // If we've already checked, the browser has been started and this is a 
-  // new window open, and we don't want to check again.
-  if (mCheckedThisSession) {
-    *aResult = false;
-    return NS_OK;
+  nsCOMPtr<nsIPrefBranch> prefs(do_GetService(NS_PREFSERVICE_CONTRACTID));
+  if (prefs) {
+    (void) prefs->SetBoolPref(PREF_CHECKDEFAULTBROWSER, true);
+    // Reset the number of times the dialog should be shown
+    // before it is silenced.
+    (void) prefs->SetIntPref(PREF_DEFAULTBROWSERCHECKCOUNT, 0);
   }
 
-  nsCOMPtr<nsIPrefBranch> prefs;
-  nsCOMPtr<nsIPrefService> pserve(do_GetService(NS_PREFSERVICE_CONTRACTID));
-  if (pserve)
-    pserve->GetBranch("", getter_AddRefs(prefs));
-
-  if (prefs)
-    prefs->GetBoolPref(PREF_CHECKDEFAULTBROWSER, aResult);
-
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsGNOMEShellService::SetShouldCheckDefaultBrowser(bool aShouldCheck)
-{
-  nsCOMPtr<nsIPrefBranch> prefs;
-  nsCOMPtr<nsIPrefService> pserve(do_GetService(NS_PREFSERVICE_CONTRACTID));
-  if (pserve)
-    pserve->GetBranch("", getter_AddRefs(prefs));
-
-  if (prefs)
-    prefs->SetBoolPref(PREF_CHECKDEFAULTBROWSER, aShouldCheck);
-
   return NS_OK;
 }
 
@@ -386,7 +359,7 @@ WriteImage(const nsCString& aPath, imgIContainer* aImage)
   return res ? NS_OK : NS_ERROR_FAILURE;
 #endif
 }
-                 
+
 NS_IMETHODIMP
 nsGNOMEShellService::SetDesktopBackground(nsIDOMElement* aElement, 
                                           int32_t aPosition)
@@ -407,15 +380,15 @@ nsGNOMEShellService::SetDesktopBackground(nsIDOMElement* aElement,
   // Set desktop wallpaper filling style
   nsAutoCString options;
   if (aPosition == BACKGROUND_TILE)
-    options.Assign("wallpaper");
+    options.AssignLiteral("wallpaper");
   else if (aPosition == BACKGROUND_STRETCH)
-    options.Assign("stretched");
+    options.AssignLiteral("stretched");
   else if (aPosition == BACKGROUND_FILL)
-    options.Assign("zoom");
+    options.AssignLiteral("zoom");
   else if (aPosition == BACKGROUND_FIT)
-    options.Assign("scaled");
+    options.AssignLiteral("scaled");
   else
-    options.Assign("centered");
+    options.AssignLiteral("centered");
 
   // Write the background file to the home directory.
   nsAutoCString filePath(PR_GetEnv("HOME"));
@@ -429,7 +402,7 @@ nsGNOMEShellService::SetDesktopBackground(nsIDOMElement* aElement,
     rv = bundleService->CreateBundle(BRAND_PROPERTIES,
                                      getter_AddRefs(brandBundle));
     if (NS_SUCCEEDED(rv) && brandBundle) {
-      rv = brandBundle->GetStringFromName(MOZ_UTF16("brandShortName"),
+      rv = brandBundle->GetStringFromName(u"brandShortName",
                                           getter_Copies(brandName));
       NS_ENSURE_SUCCESS(rv, rv);
     }
@@ -438,7 +411,7 @@ nsGNOMEShellService::SetDesktopBackground(nsIDOMElement* aElement,
   // build the file name
   filePath.Append('/');
   filePath.Append(NS_ConvertUTF16toUTF8(brandName));
-  filePath.Append("_wallpaper.png");
+  filePath.AppendLiteral("_wallpaper.png");
 
   // write the image to a file in the home dir
   rv = WriteImage(filePath, container);
@@ -478,7 +451,7 @@ nsGNOMEShellService::SetDesktopBackground(nsIDOMElement* aElement,
 
     // Set the image to an empty string first to force a refresh
     // (since we could be writing a new image on top of an existing
-    // Firefox_wallpaper.png and nautilus doesn't monitor the file for changes)
+    // PaleMoon_wallpaper.png and nautilus doesn't monitor the file for changes)
     gconf->SetString(NS_LITERAL_CSTRING(kDesktopImageKey),
                      EmptyCString());
 
@@ -543,7 +516,7 @@ ColorToCString(uint32_t aColor, nsCString& aResult)
   uint16_t green = COLOR_8_TO_16_BIT((aColor >> 8) & 0xff);
   uint16_t blue = COLOR_8_TO_16_BIT(aColor & 0xff);
 
-  PR_snprintf(buf, 14, "#%04x%04x%04x", red, green, blue);
+  snprintf(buf, 14, "#%04x%04x%04x", red, green, blue);
 }
 
 NS_IMETHODIMP
@@ -580,9 +553,9 @@ nsGNOMEShellService::OpenApplication(int32_t aApplication)
 {
   nsAutoCString scheme;
   if (aApplication == APPLICATION_MAIL)
-    scheme.Assign("mailto");
+    scheme.AssignLiteral("mailto");
   else if (aApplication == APPLICATION_NEWS)
-    scheme.Assign("news");
+    scheme.AssignLiteral("news");
   else
     return NS_ERROR_NOT_AVAILABLE;
 
diff --git a/application/palemoon/components/shell/nsGNOMEShellService.h b/application/palemoon/components/shell/nsGNOMEShellService.h
index 36a4a0c42..a7b003802 100644
--- a/application/palemoon/components/shell/nsGNOMEShellService.h
+++ b/application/palemoon/components/shell/nsGNOMEShellService.h
@@ -6,28 +6,28 @@
 #ifndef nsgnomeshellservice_h____
 #define nsgnomeshellservice_h____
 
-#include "nsIShellService.h"
+#include "nsIGNOMEShellService.h"
 #include "nsStringAPI.h"
 #include "mozilla/Attributes.h"
 
-class nsGNOMEShellService final : public nsIShellService
+class nsGNOMEShellService final : public nsIGNOMEShellService
 {
 public:
-  nsGNOMEShellService() : mCheckedThisSession(false), mAppIsInPath(false) { }
+  nsGNOMEShellService() : mAppIsInPath(false) { }
 
   NS_DECL_ISUPPORTS
   NS_DECL_NSISHELLSERVICE
+  NS_DECL_NSIGNOMESHELLSERVICE
 
-  nsresult Init() NS_HIDDEN;
+  nsresult Init();
 
 private:
   ~nsGNOMEShellService() {}
 
-  NS_HIDDEN_(bool) KeyMatchesAppName(const char *aKeyValue) const;
-  NS_HIDDEN_(bool) CheckHandlerMatchesAppName(const nsACString& handler) const;
+  bool KeyMatchesAppName(const char *aKeyValue) const;
+  bool CheckHandlerMatchesAppName(const nsACString& handler) const;
 
-  NS_HIDDEN_(bool) GetAppPathFromLauncher();
-  bool mCheckedThisSession;
+  bool GetAppPathFromLauncher();
   bool mUseLocaleFilenames;
   nsCString    mAppPath;
   bool mAppIsInPath;
diff --git a/application/palemoon/components/shell/nsIGNOMEShellService.idl b/application/palemoon/components/shell/nsIGNOMEShellService.idl
new file mode 100644
index 000000000..842ce5e8a
--- /dev/null
+++ b/application/palemoon/components/shell/nsIGNOMEShellService.idl
@@ -0,0 +1,19 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsIShellService.idl"
+
+[scriptable, uuid(2ce5c803-edcd-443d-98eb-ceba86d02d13)]
+interface nsIGNOMEShellService : nsIShellService
+{
+  /**
+   * Used to determine whether or not to offer "Set as desktop background"
+   * functionality. Even if shell service is available it is not
+   * guaranteed that it is able to set the background for every desktop
+   * which is especially true for Linux with its many different desktop
+   * environments.
+   */
+  readonly attribute boolean canSetDesktopBackground;
+};
+
diff --git a/application/palemoon/components/shell/nsIMacShellService.idl b/application/palemoon/components/shell/nsIMacShellService.idl
index 3c2f42315..6a532bbd0 100644
--- a/application/palemoon/components/shell/nsIMacShellService.idl
+++ b/application/palemoon/components/shell/nsIMacShellService.idl
@@ -5,7 +5,7 @@
 
 #include "nsIShellService.idl"
 
-[scriptable, uuid(7f8ca08e-1df4-4735-86e9-50dedb48e5e8)]
+[scriptable, uuid(387fdc80-0077-4b60-a0d9-d9e80a83ba64)]
 interface nsIMacShellService : nsIShellService
 {
   const long APPLICATION_KEYCHAIN_ACCESS  = 2;
diff --git a/application/palemoon/components/shell/nsIShellService.idl b/application/palemoon/components/shell/nsIShellService.idl
index 4825741b3..3e7e94b00 100644
--- a/application/palemoon/components/shell/nsIShellService.idl
+++ b/application/palemoon/components/shell/nsIShellService.idl
@@ -8,7 +8,7 @@
 interface nsIDOMElement;
 interface nsIFile;
 
-[scriptable, uuid(99d2e9f1-3c86-40f7-81fd-3060c18489f0)]
+[scriptable, uuid(2d1a95e4-5bd8-4eeb-b0a8-c1455fd2a357)]
 interface nsIShellService : nsISupports
 {
   /**
@@ -39,23 +39,6 @@ interface nsIShellService : nsISupports
   void setDefaultBrowser(in boolean aClaimAllTypes, in boolean aForAllUsers);
 
   /** 
-   * Used to determine whether or not to show a "Set Default Browser"
-   * query dialog. This attribute is true if the application is starting
-   * up and "browser.shell.checkDefaultBrowser" is true, otherwise it
-   * is false.
-   */
-  attribute boolean shouldCheckDefaultBrowser;
-
-  /**
-   * Used to determine whether or not to offer "Set as desktop background"
-   * functionality. Even if shell service is available it is not
-   * guaranteed that it is able to set the background for every desktop
-   * which is especially true for Linux with its many different desktop
-   * environments.
-   */
-  readonly attribute boolean canSetDesktopBackground;
-
-  /** 
    * Flags for positioning/sizing of the Desktop Background image.
    */
   const long BACKGROUND_TILE      = 1;
diff --git a/application/palemoon/components/shell/nsIWindowsShellService.idl b/application/palemoon/components/shell/nsIWindowsShellService.idl
index 913eb4292..57ed37055 100644
--- a/application/palemoon/components/shell/nsIWindowsShellService.idl
+++ b/application/palemoon/components/shell/nsIWindowsShellService.idl
@@ -5,7 +5,7 @@
 
 #include "nsIShellService.idl"
 
-[scriptable, uuid(89b0a761-d9a0-4c39-ab83-d81566459a31)]
+[scriptable, uuid(f8a26b94-49e5-4441-8fbc-315e0b4f22ef)]
 interface nsIWindowsShellService : nsIShellService
 {
     /**
diff --git a/application/palemoon/components/shell/nsMacShellService.cpp b/application/palemoon/components/shell/nsMacShellService.cpp
index 914b9ae65..d8d64039d 100644
--- a/application/palemoon/components/shell/nsMacShellService.cpp
+++ b/application/palemoon/components/shell/nsMacShellService.cpp
@@ -17,13 +17,13 @@
 #include "nsIURL.h"
 #include "nsIWebBrowserPersist.h"
 #include "nsMacShellService.h"
-#include "nsNetUtil.h"
+#include "nsIProperties.h"
+#include "nsServiceManagerUtils.h"
 #include "nsShellService.h"
 #include "nsStringAPI.h"
 #include "nsIDocShell.h"
 #include "nsILoadContext.h"
 
-
 #include <CoreFoundation/CoreFoundation.h>
 #include <ApplicationServices/ApplicationServices.h>
 
@@ -49,19 +49,14 @@ nsMacShellService::IsDefaultBrowser(bool aStartupCheck,
     return NS_ERROR_FAILURE;
   }
 
-  // Get the default http handler's bundle ID (or nullptr if it has not been explicitly set)
+  // Get the default http handler's bundle ID (or nullptr if it has not been
+  // explicitly set)
   CFStringRef defaultBrowserID = ::LSCopyDefaultHandlerForURLScheme(CFSTR("http"));
   if (defaultBrowserID) {
     *aIsDefaultBrowser = ::CFStringCompare(firefoxID, defaultBrowserID, 0) == kCFCompareEqualTo;
     ::CFRelease(defaultBrowserID);
   }
 
-  // If this is the first browser window, maintain internal state that we've
-  // checked this session (so that subsequent window opens don't show the 
-  // default browser dialog).
-  if (aStartupCheck)
-    mCheckedThisSession = true;
-
   return NS_OK;
 }
 
@@ -90,47 +85,15 @@ nsMacShellService::SetDefaultBrowser(bool aClaimAllTypes, bool aForAllUsers)
       return NS_ERROR_FAILURE;
     }
   }
-  
-  return NS_OK;
-}
 
-NS_IMETHODIMP
-nsMacShellService::GetShouldCheckDefaultBrowser(bool* aResult)
-{
-  // If we've already checked, the browser has been started and this is a 
-  // new window open, and we don't want to check again.
-  if (mCheckedThisSession) {
-    *aResult = false;
-    return NS_OK;
+  nsCOMPtr<nsIPrefBranch> prefs(do_GetService(NS_PREFSERVICE_CONTRACTID));
+  if (prefs) {
+    (void) prefs->SetBoolPref(PREF_CHECKDEFAULTBROWSER, true);
+    // Reset the number of times the dialog should be shown
+    // before it is silenced.
+    (void) prefs->SetIntPref(PREF_DEFAULTBROWSERCHECKCOUNT, 0);
   }
 
-  nsCOMPtr<nsIPrefBranch> prefs;
-  nsCOMPtr<nsIPrefService> pserve(do_GetService(NS_PREFSERVICE_CONTRACTID));
-  if (pserve)
-    pserve->GetBranch("", getter_AddRefs(prefs));
-
-  prefs->GetBoolPref(PREF_CHECKDEFAULTBROWSER, aResult);
-
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsMacShellService::SetShouldCheckDefaultBrowser(bool aShouldCheck)
-{
-  nsCOMPtr<nsIPrefBranch> prefs;
-  nsCOMPtr<nsIPrefService> pserve(do_GetService(NS_PREFSERVICE_CONTRACTID));
-  if (pserve)
-    pserve->GetBranch("", getter_AddRefs(prefs));
-
-  prefs->SetBoolPref(PREF_CHECKDEFAULTBROWSER, aShouldCheck);
-
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsMacShellService::GetCanSetDesktopBackground(bool* aResult)
-{
-  *aResult = true;
   return NS_OK;
 }
 
@@ -202,8 +165,10 @@ nsMacShellService::SetDesktopBackground(nsIDOMElement* aElement,
     loadContext = do_QueryInterface(docShell);
   }
 
-  return wbp->SaveURI(imageURI, nullptr, docURI, content->OwnerDoc()->GetReferrerPolicy(),
-                      nullptr, nullptr, mBackgroundFile, loadContext);
+  return wbp->SaveURI(imageURI, nullptr,
+                      docURI, content->OwnerDoc()->GetReferrerPolicy(),
+                      nullptr, nullptr,
+                      mBackgroundFile, loadContext);
 }
 
 NS_IMETHODIMP
@@ -269,7 +234,8 @@ nsMacShellService::OnStateChange(nsIWebProgress* aWebProgress,
     OSStatus status;
 
     // Convert the path into a FSRef
-    status = ::FSPathMakeRef((const UInt8*)nativePath.get(), &pictureRef, nullptr);
+    status = ::FSPathMakeRef((const UInt8*)nativePath.get(), &pictureRef,
+                             nullptr);
     if (status == noErr) {
       err = ::FSNewAlias(nil, &pictureRef, &aliasHandle);
       if (err == noErr && aliasHandle == nil)
@@ -336,8 +302,8 @@ nsMacShellService::OpenApplication(int32_t aApplication)
     }
     break;
   case nsIMacShellService::APPLICATION_KEYCHAIN_ACCESS:
-    err = ::LSGetApplicationForInfo('APPL', 'kcmr', nullptr, kLSRolesAll, nullptr,
-                                    &appURL);
+    err = ::LSGetApplicationForInfo('APPL', 'kcmr', nullptr, kLSRolesAll,
+                                    nullptr, &appURL);
     break;
   case nsIMacShellService::APPLICATION_NETWORK:
     {
@@ -349,8 +315,7 @@ nsMacShellService::OpenApplication(int32_t aApplication)
       if (!exists)
         return NS_ERROR_FILE_NOT_FOUND;
       return lf->Launch();
-    }  
-    break;
+    }
   case nsIMacShellService::APPLICATION_DESKTOP:
     {
       nsCOMPtr<nsIFile> lf;
@@ -361,8 +326,7 @@ nsMacShellService::OpenApplication(int32_t aApplication)
       if (!exists)
         return NS_ERROR_FILE_NOT_FOUND;
       return lf->Launch();
-    }  
-    break;
+    }
   }
 
   if (appURL && err == noErr) {
diff --git a/application/palemoon/components/shell/nsMacShellService.h b/application/palemoon/components/shell/nsMacShellService.h
index 7ca1c71ac..db9527809 100644
--- a/application/palemoon/components/shell/nsMacShellService.h
+++ b/application/palemoon/components/shell/nsMacShellService.h
@@ -15,7 +15,7 @@ class nsMacShellService : public nsIMacShellService,
                           public nsIWebProgressListener
 {
 public:
-  nsMacShellService() : mCheckedThisSession(false) {};
+  nsMacShellService() {};
 
   NS_DECL_ISUPPORTS
   NS_DECL_NSISHELLSERVICE
@@ -27,8 +27,6 @@ protected:
 
 private:
   nsCOMPtr<nsIFile> mBackgroundFile;
-
-  bool      mCheckedThisSession;
 };
 
 #endif // nsmacshellservice_h____
diff --git a/application/palemoon/components/shell/nsSetDefaultBrowser.js b/application/palemoon/components/shell/nsSetDefaultBrowser.js
index d1d1e72cb..c7a78c538 100644
--- a/application/palemoon/components/shell/nsSetDefaultBrowser.js
+++ b/application/palemoon/components/shell/nsSetDefaultBrowser.js
@@ -2,13 +2,14 @@
  * 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/. */
 
-/* 
- * -setDefaultBrowser commandline handler
+/*
+ * --setDefaultBrowser commandline handler
  * Makes the current executable the "default browser".
  */
 
 const Cc = Components.classes;
 const Ci = Components.interfaces;
+Components.utils.import("resource:///modules/ShellService.jsm");
 Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
 
 function nsSetDefaultBrowser() {}
@@ -16,13 +17,11 @@ function nsSetDefaultBrowser() {}
 nsSetDefaultBrowser.prototype = {
   handle: function nsSetDefault_handle(aCmdline) {
     if (aCmdline.handleFlag("setDefaultBrowser", false)) {
-      var shell = Cc["@mozilla.org/browser/shell-service;1"].
-                  getService(Ci.nsIShellService);
-      shell.setDefaultBrowser(true, true);
+      ShellService.setDefaultBrowser(true, true);
     }
   },
 
-  helpInfo: "  -setDefaultBrowser                  Set this app as the default browser.\n",
+  helpInfo: "  --setDefaultBrowser                          Set this app as the default browser.\n",
 
   classID: Components.ID("{F57899D0-4E2C-4ac6-9E29-50C736103B0C}"),
   QueryInterface: XPCOMUtils.generateQI([Ci.nsICommandLineHandler]),
diff --git a/application/palemoon/components/shell/nsShellService.h b/application/palemoon/components/shell/nsShellService.h
index d5fade37b..516a8423a 100644
--- a/application/palemoon/components/shell/nsShellService.h
+++ b/application/palemoon/components/shell/nsShellService.h
@@ -4,6 +4,8 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #define PREF_CHECKDEFAULTBROWSER "browser.shell.checkDefaultBrowser"
+#define PREF_SKIPDEFAULTBROWSERCHECK "browser.shell.skipDefaultBrowserCheck"
+#define PREF_DEFAULTBROWSERCHECKCOUNT "browser.shell.defaultBrowserCheckCount"
 
 #define SHELLSERVICE_PROPERTIES "chrome://browser/locale/shellservice.properties"
 #define BRAND_PROPERTIES "chrome://branding/locale/brand.properties"
diff --git a/application/palemoon/components/shell/nsWindowsShellService.cpp b/application/palemoon/components/shell/nsWindowsShellService.cpp
index 813ec4fe1..c4039b95a 100644
--- a/application/palemoon/components/shell/nsWindowsShellService.cpp
+++ b/application/palemoon/components/shell/nsWindowsShellService.cpp
@@ -3,6 +3,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+#include "nsWindowsShellService.h"
+
 #include "imgIContainer.h"
 #include "imgIRequest.h"
 #include "mozilla/gfx/2D.h"
@@ -15,8 +17,8 @@
 #include "nsIServiceManager.h"
 #include "nsIStringBundle.h"
 #include "nsNetUtil.h"
+#include "nsServiceManagerUtils.h"
 #include "nsShellService.h"
-#include "nsWindowsShellService.h"
 #include "nsIProcess.h"
 #include "nsICategoryManager.h"
 #include "nsBrowserCompsCID.h"
@@ -27,6 +29,7 @@
 #include "nsUnicharUtils.h"
 #include "nsIWinTaskbar.h"
 #include "nsISupportsPrimitives.h"
+#include "nsIURLFormatter.h"
 #include "nsThreadUtils.h"
 #include "nsXULAppAPI.h"
 #include "mozilla/WindowsVersion.h"
@@ -47,6 +50,9 @@
 #include <mbstring.h>
 #include <shlwapi.h>
 
+#include <lm.h>
+#undef ACCESS_READ
+
 #ifndef MAX_BUF
 #define MAX_BUF 4096
 #endif
@@ -129,7 +135,7 @@ OpenKeyForReading(HKEY aKeyRoot, const nsAString& aKeyName, HKEY* aKey)
 //   The following keys are set to make PaleMoon appear in the Start Menu as the
 //   browser:
 //   
-//   HKCU\SOFTWARE\Clients\StartMenuInternet\FIREFOX.EXE\
+//   HKCU\SOFTWARE\Clients\StartMenuInternet\PaleMoon.EXE\
 //                                      (default)         REG_SZ     <appname>
 //     DefaultIcon                      (default)         REG_SZ     <apppath>,0
 //     InstallInfo                      HideIconsCommand  REG_SZ     <uninstpath> /HideShortcuts
@@ -278,20 +284,15 @@ nsWindowsShellService::ShortcutMaintenance()
     return NS_ERROR_UNEXPECTED;
 
   NS_NAMED_LITERAL_CSTRING(prefName, "browser.taskbar.lastgroupid");
-  nsCOMPtr<nsIPrefService> prefs =
+  nsCOMPtr<nsIPrefBranch> prefs =
     do_GetService(NS_PREFSERVICE_CONTRACTID);
   if (!prefs)
     return NS_ERROR_UNEXPECTED;
 
-  nsCOMPtr<nsIPrefBranch> prefBranch;
-  prefs->GetBranch(nullptr, getter_AddRefs(prefBranch));
-  if (!prefBranch)
-    return NS_ERROR_UNEXPECTED;
-
   nsCOMPtr<nsISupportsString> prefString;
-  rv = prefBranch->GetComplexValue(prefName.get(),
-                                   NS_GET_IID(nsISupportsString),
-                                   getter_AddRefs(prefString));
+  rv = prefs->GetComplexValue(prefName.get(),
+                              NS_GET_IID(nsISupportsString),
+                              getter_AddRefs(prefString));
   if (NS_SUCCEEDED(rv)) {
     nsAutoString version;
     prefString->GetData(version);
@@ -307,9 +308,9 @@ nsWindowsShellService::ShortcutMaintenance()
     return rv;
 
   prefString->SetData(appId);
-  rv = prefBranch->SetComplexValue(prefName.get(),
-                                   NS_GET_IID(nsISupportsString),
-                                   prefString);
+  rv = prefs->SetComplexValue(prefName.get(),
+                              NS_GET_IID(nsISupportsString),
+                              prefString);
   if (NS_FAILED(rv)) {
     NS_WARNING("Couldn't set last user model id!");
     return NS_ERROR_UNEXPECTED;
@@ -325,38 +326,47 @@ nsWindowsShellService::ShortcutMaintenance()
 }
 
 static bool
-IsAARDefaultHTTP(IApplicationAssociationRegistration* pAAR,
-                 bool* aIsDefaultBrowser)
+IsAARDefault(const RefPtr<IApplicationAssociationRegistration>& pAAR,
+             LPCWSTR aClassName)
 {
   // Make sure the Prog ID matches what we have
   LPWSTR registeredApp;
-  HRESULT hr = pAAR->QueryCurrentDefault(L"http", AT_URLPROTOCOL, AL_EFFECTIVE,
+  bool isProtocol = *aClassName != L'.';
+  ASSOCIATIONTYPE queryType = isProtocol ? AT_URLPROTOCOL : AT_FILEEXTENSION;
+  HRESULT hr = pAAR->QueryCurrentDefault(aClassName, queryType, AL_EFFECTIVE,
                                          &registeredApp);
-  if (SUCCEEDED(hr)) {
-    LPCWSTR firefoxHTTPProgID = L"PaleMoonURL";
-    *aIsDefaultBrowser = !wcsicmp(registeredApp, firefoxHTTPProgID);
-    CoTaskMemFree(registeredApp);
-  } else {
-    *aIsDefaultBrowser = false;
+  if (FAILED(hr)) {
+    return false;
   }
-  return SUCCEEDED(hr);
+
+  LPCWSTR progID = isProtocol ? L"PaleMoonURL" : L"PaleMoonHTML";
+  bool isDefault = !wcsicmp(registeredApp, progID);
+  CoTaskMemFree(registeredApp);
+
+  return isDefault;
 }
 
-static bool
-IsAARDefaultHTML(IApplicationAssociationRegistration* pAAR,
-                 bool* aIsDefaultBrowser)
+static void
+IsDefaultBrowserWin8(bool aCheckAllTypes, bool* aIsDefaultBrowser)
 {
-  LPWSTR registeredApp;
-  HRESULT hr = pAAR->QueryCurrentDefault(L".html", AT_FILEEXTENSION, AL_EFFECTIVE,
-                                         &registeredApp);
-  if (SUCCEEDED(hr)) {
-    LPCWSTR firefoxHTMLProgID = L"PaleMoonHTML";
-    *aIsDefaultBrowser = !wcsicmp(registeredApp, firefoxHTMLProgID);
-    CoTaskMemFree(registeredApp);
-  } else {
-    *aIsDefaultBrowser = false;
+  RefPtr<IApplicationAssociationRegistration> pAAR;
+  HRESULT hr = CoCreateInstance(CLSID_ApplicationAssociationRegistration,
+                                nullptr,
+                                CLSCTX_INPROC,
+                                IID_IApplicationAssociationRegistration,
+                                getter_AddRefs(pAAR));
+  if (FAILED(hr)) {
+    return;
+  }
+
+  bool res = IsAARDefault(pAAR, L"http");
+  if (*aIsDefaultBrowser) {
+    *aIsDefaultBrowser = res;
+  }
+  res = IsAARDefault(pAAR, L".html");
+  if (*aIsDefaultBrowser && aCheckAllTypes) {
+    *aIsDefaultBrowser = res;
   }
-  return SUCCEEDED(hr);
 }
 
 /*
@@ -369,37 +379,27 @@ bool
 nsWindowsShellService::IsDefaultBrowserVista(bool aCheckAllTypes,
                                              bool* aIsDefaultBrowser)
 {
-  IApplicationAssociationRegistration* pAAR;
+  RefPtr<IApplicationAssociationRegistration> pAAR;
   HRESULT hr = CoCreateInstance(CLSID_ApplicationAssociationRegistration,
                                 nullptr,
                                 CLSCTX_INPROC,
                                 IID_IApplicationAssociationRegistration,
-                                (void**)&pAAR);
-
-  if (SUCCEEDED(hr)) {
-    if (aCheckAllTypes) {
-      BOOL res;
-      hr = pAAR->QueryAppIsDefaultAll(AL_EFFECTIVE,
-                                      APP_REG_NAME,
-                                      &res);
-      *aIsDefaultBrowser = res;
-
-      // If we have all defaults, let's make sure that our ProgID
-      // is explicitly returned as well. Needed only for Windows 8.
-      if (*aIsDefaultBrowser && IsWin8OrLater()) {
-        IsAARDefaultHTTP(pAAR, aIsDefaultBrowser);
-        if (*aIsDefaultBrowser) {
-          IsAARDefaultHTML(pAAR, aIsDefaultBrowser);
-        }
-      }
-    } else {
-      IsAARDefaultHTTP(pAAR, aIsDefaultBrowser);
-    }
+                                getter_AddRefs(pAAR));
+  if (FAILED(hr)) {
+    return false;
+  }
 
-    pAAR->Release();
-    return true;
+  if (aCheckAllTypes) {
+    BOOL res;
+    hr = pAAR->QueryAppIsDefaultAll(AL_EFFECTIVE,
+                                    APP_REG_NAME,
+                                    &res);
+    *aIsDefaultBrowser = res;
+  } else if (!IsWin8OrLater()) {
+    *aIsDefaultBrowser = IsAARDefault(pAAR, L"http");
   }
-  return false;
+
+  return true;
 }
 
 NS_IMETHODIMP
@@ -407,12 +407,6 @@ nsWindowsShellService::IsDefaultBrowser(bool aStartupCheck,
                                         bool aForAllTypes,
                                         bool* aIsDefaultBrowser)
 {
-  // If this is the first browser window, maintain internal state that we've
-  // checked this session (so that subsequent window opens don't show the
-  // default browser dialog).
-  if (aStartupCheck)
-    mCheckedThisSession = true;
-
   // Assume we're the default unless one of the several checks below tell us
   // otherwise.
   *aIsDefaultBrowser = true;
@@ -499,6 +493,9 @@ nsWindowsShellService::IsDefaultBrowser(bool aStartupCheck,
   // previous checks show that PaleMoon is the default browser.
   if (*aIsDefaultBrowser) {
     IsDefaultBrowserVista(aForAllTypes, aIsDefaultBrowser);
+    if (IsWin8OrLater()) {
+      IsDefaultBrowserWin8(aForAllTypes, aIsDefaultBrowser);
+    }
   }
 
   // To handle the case where DDE isn't disabled due for a user because there
@@ -603,13 +600,6 @@ nsWindowsShellService::IsDefaultBrowser(bool aStartupCheck,
   return NS_OK;
 }
 
-NS_IMETHODIMP
-nsWindowsShellService::GetCanSetDesktopBackground(bool* aResult)
-{
-  *aResult = true;
-  return NS_OK;
-}
-
 static nsresult
 DynSHOpenWithDialog(HWND hwndParent, const OPENASINFO *poainfo)
 {
@@ -628,14 +618,34 @@ DynSHOpenWithDialog(HWND hwndParent, const OPENASINFO *poainfo)
     return NS_ERROR_FAILURE;
   }
 
-  nsresult rv = 
-    SUCCEEDED(SHOpenWithDialogFn(hwndParent, poainfo)) ? NS_OK :
-                                                         NS_ERROR_FAILURE;
+  nsresult rv;
+  HRESULT hr = SHOpenWithDialogFn(hwndParent, poainfo);
+  if (SUCCEEDED(hr) || (hr == HRESULT_FROM_WIN32(ERROR_CANCELLED))) {
+    rv = NS_OK;
+  } else {
+    rv = NS_ERROR_FAILURE;
+  }
   FreeLibrary(shellDLL);
   return rv;
 }
 
 nsresult
+nsWindowsShellService::LaunchControlPanelDefaultsSelectionUI()
+{
+  IApplicationAssociationRegistrationUI* pAARUI;
+  HRESULT hr = CoCreateInstance(CLSID_ApplicationAssociationRegistrationUI,
+                                NULL,
+                                CLSCTX_INPROC,
+                                IID_IApplicationAssociationRegistrationUI,
+                                (void**)&pAARUI);
+  if (SUCCEEDED(hr)) {
+    hr = pAARUI->LaunchAdvancedAssociationUI(APP_REG_NAME);
+    pAARUI->Release();
+  }
+  return SUCCEEDED(hr) ? NS_OK : NS_ERROR_FAILURE;
+}
+
+nsresult
 nsWindowsShellService::LaunchControlPanelDefaultPrograms()
 {
   // Build the path control.exe path safely
@@ -651,7 +661,8 @@ nsWindowsShellService::LaunchControlPanelDefaultPrograms()
     return NS_ERROR_FAILURE;
   }
 
-  WCHAR params[] = L"control.exe /name Microsoft.DefaultPrograms /page pageDefaultProgram";
+  WCHAR params[] = L"control.exe /name Microsoft.DefaultPrograms /page "
+    "pageDefaultProgram\\pageAdvancedSettings?pszAppName=" APP_REG_NAME;
   STARTUPINFOW si = {sizeof(si), 0};
   si.dwFlags = STARTF_USESHOWWINDOW;
   si.wShowWindow = SW_SHOWDEFAULT;
@@ -666,9 +677,62 @@ nsWindowsShellService::LaunchControlPanelDefaultPrograms()
   return NS_OK;
 }
 
+static bool
+IsWindowsLogonConnected()
+{
+  WCHAR userName[UNLEN + 1];
+  DWORD size = ArrayLength(userName);
+  if (!GetUserNameW(userName, &size)) {
+    return false;
+  }
+
+  LPUSER_INFO_24 info;
+  if (NetUserGetInfo(nullptr, userName, 24, (LPBYTE *)&info)
+      != NERR_Success) {
+    return false;
+  }
+  bool connected = info->usri24_internet_identity;
+  NetApiBufferFree(info);
+
+  return connected;
+}
+
+static bool
+SettingsAppBelievesConnected()
+{
+  nsresult rv;
+  nsCOMPtr<nsIWindowsRegKey> regKey =
+    do_CreateInstance("@mozilla.org/windows-registry-key;1", &rv);
+  if (NS_FAILED(rv)) {
+    return false;
+  }
+
+  rv = regKey->Open(nsIWindowsRegKey::ROOT_KEY_CURRENT_USER,
+                    NS_LITERAL_STRING("SOFTWARE\\Microsoft\\Windows\\Shell\\Associations"),
+                    nsIWindowsRegKey::ACCESS_READ);
+  if (NS_FAILED(rv)) {
+    return false;
+  }
+
+  uint32_t value;
+  rv = regKey->ReadIntValue(NS_LITERAL_STRING("IsConnectedAtLogon"), &value);
+  if (NS_FAILED(rv)) {
+    return false;
+  }
+
+  return !!value;
+}
+
 nsresult
 nsWindowsShellService::LaunchModernSettingsDialogDefaultApps()
 {
+  if (!IsWindowsBuildOrLater(14965) &&
+      !IsWindowsLogonConnected() && SettingsAppBelievesConnected()) {
+    // Use the classic Control Panel to work around a bug of older
+    // builds of Windows 10.
+    return LaunchControlPanelDefaultPrograms();
+  }
+
   IApplicationActivationManager* pActivator;
   HRESULT hr = CoCreateInstance(CLSID_ApplicationActivationManager,
                                 nullptr,
@@ -682,6 +746,15 @@ nsWindowsShellService::LaunchModernSettingsDialogDefaultApps()
            L"windows.immersivecontrolpanel_cw5n1h2txyewy"
            L"!microsoft.windows.immersivecontrolpanel",
            L"page=SettingsPageAppsDefaults", AO_NONE, &pid);
+    if (SUCCEEDED(hr)) {
+      // Do not check error because we could at least open
+      // the "Default apps" setting.
+      pActivator->ActivateApplication(
+             L"windows.immersivecontrolpanel_cw5n1h2txyewy"
+             L"!microsoft.windows.immersivecontrolpanel",
+             L"page=SettingsPageAppsDefaults"
+             L"&target=SystemSettings_DefaultApps_Browser", AO_NONE, &pid);
+    }
     pActivator->Release();
     return SUCCEEDED(hr) ? NS_OK : NS_ERROR_FAILURE;
   }
@@ -689,6 +762,36 @@ nsWindowsShellService::LaunchModernSettingsDialogDefaultApps()
 }
 
 nsresult
+nsWindowsShellService::InvokeHTTPOpenAsVerb()
+{
+  nsCOMPtr<nsIURLFormatter> formatter(
+    do_GetService("@mozilla.org/toolkit/URLFormatterService;1"));
+  if (!formatter) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  nsString urlStr;
+  nsresult rv = formatter->FormatURLPref(
+    NS_LITERAL_STRING("app.support.baseURL"), urlStr);
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+  if (!StringBeginsWith(urlStr, NS_LITERAL_STRING("https://"))) {
+    return NS_ERROR_FAILURE;
+  }
+  urlStr.AppendLiteral("win10-default-browser");
+
+  SHELLEXECUTEINFOW seinfo = { sizeof(SHELLEXECUTEINFOW) };
+  seinfo.lpVerb = L"openas";
+  seinfo.lpFile = urlStr.get();
+  seinfo.nShow = SW_SHOWNORMAL;
+  if (!ShellExecuteExW(&seinfo)) {
+    return NS_ERROR_FAILURE;
+  }
+  return NS_OK;
+}
+
+nsresult
 nsWindowsShellService::LaunchHTTPHandlerPane()
 {
   OPENASINFO info;
@@ -716,16 +819,23 @@ nsWindowsShellService::SetDefaultBrowser(bool aClaimAllTypes, bool aForAllUsers)
   nsresult rv = LaunchHelper(appHelperPath);
   if (NS_SUCCEEDED(rv) && IsWin8OrLater()) {
     if (aClaimAllTypes) {
-      rv = LaunchControlPanelDefaultPrograms();
+      if (IsWin10OrLater()) {
+        rv = LaunchModernSettingsDialogDefaultApps();
+      } else {
+        rv = LaunchControlPanelDefaultsSelectionUI();
+      }
       // The above call should never really fail, but just in case
       // fall back to showing the HTTP association screen only.
       if (NS_FAILED(rv)) {
-        rv = LaunchHTTPHandlerPane();
+        if (IsWin10OrLater()) {
+          rv = InvokeHTTPOpenAsVerb();
+        } else {
+          rv = LaunchHTTPHandlerPane();
+        }
       }
     } else {
-      // Windows 10 blocks attempts to load the HTTP Handler
-      // association dialog, so the modern Settings dialog
-      // is opened with the Default Apps view loaded.
+      // Windows 10 blocks attempts to load the
+      // HTTP Handler association dialog.
       if (IsWin10OrLater()) {
         rv = LaunchModernSettingsDialogDefaultApps();
       } else {
@@ -735,50 +845,20 @@ nsWindowsShellService::SetDefaultBrowser(bool aClaimAllTypes, bool aForAllUsers)
       // The above call should never really fail, but just in case
       // fall back to showing control panel for all defaults
       if (NS_FAILED(rv)) {
-        rv = LaunchControlPanelDefaultPrograms();
+        rv = LaunchControlPanelDefaultsSelectionUI();
       }
     }
   }
 
-  return rv;
-}
-
-NS_IMETHODIMP
-nsWindowsShellService::GetShouldCheckDefaultBrowser(bool* aResult)
-{
-  NS_ENSURE_ARG_POINTER(aResult);
-
-  // If we've already checked, the browser has been started and this is a 
-  // new window open, and we don't want to check again.
-  if (mCheckedThisSession) {
-    *aResult = false;
-    return NS_OK;
+  nsCOMPtr<nsIPrefBranch> prefs(do_GetService(NS_PREFSERVICE_CONTRACTID));
+  if (prefs) {
+    (void) prefs->SetBoolPref(PREF_CHECKDEFAULTBROWSER, true);
+    // Reset the number of times the dialog should be shown
+    // before it is silenced.
+    (void) prefs->SetIntPref(PREF_DEFAULTBROWSERCHECKCOUNT, 0);
   }
 
-  nsCOMPtr<nsIPrefBranch> prefs;
-  nsresult rv;
-  nsCOMPtr<nsIPrefService> pserve(do_GetService(NS_PREFSERVICE_CONTRACTID, &rv));
-  NS_ENSURE_SUCCESS(rv, rv);
-
-  rv = pserve->GetBranch("", getter_AddRefs(prefs));
-  NS_ENSURE_SUCCESS(rv, rv);
-
-  return prefs->GetBoolPref(PREF_CHECKDEFAULTBROWSER, aResult);
-}
-
-NS_IMETHODIMP
-nsWindowsShellService::SetShouldCheckDefaultBrowser(bool aShouldCheck)
-{
-  nsCOMPtr<nsIPrefBranch> prefs;
-  nsresult rv;
-
-  nsCOMPtr<nsIPrefService> pserve(do_GetService(NS_PREFSERVICE_CONTRACTID, &rv));
-  NS_ENSURE_SUCCESS(rv, rv);
-  
-  rv = pserve->GetBranch("", getter_AddRefs(prefs));
-  NS_ENSURE_SUCCESS(rv, rv);
-
-  return prefs->SetBoolPref(PREF_CHECKDEFAULTBROWSER, aShouldCheck);
+  return rv;
 }
 
 static nsresult
@@ -912,7 +992,7 @@ nsWindowsShellService::SetDesktopBackground(nsIDOMElement* aElement,
   // e.g. "Desktop Background.bmp"
   nsString fileLeafName;
   rv = shellBundle->GetStringFromName
-                      (MOZ_UTF16("desktopBackgroundLeafNameWin"),
+                      (u"desktopBackgroundLeafNameWin",
                        getter_Copies(fileLeafName));
   NS_ENSURE_SUCCESS(rv, rv);
 
@@ -948,24 +1028,24 @@ nsWindowsShellService::SetDesktopBackground(nsIDOMElement* aElement,
     nsAutoString style;
     switch (aPosition) {
       case BACKGROUND_TILE:
-        style.AssignLiteral("0");
-        tile.AssignLiteral("1");
+        style.Assign('0');
+        tile.Assign('1');
         break;
       case BACKGROUND_CENTER:
-        style.AssignLiteral("0");
-        tile.AssignLiteral("0");
+        style.Assign('0');
+        tile.Assign('0');
         break;
       case BACKGROUND_STRETCH:
-        style.AssignLiteral("2");
-        tile.AssignLiteral("0");
+        style.Assign('2');
+        tile.Assign('0');
         break;
       case BACKGROUND_FILL:
         style.AssignLiteral("10");
-        tile.AssignLiteral("0");
+        tile.Assign('0');
         break;
       case BACKGROUND_FIT:
-        style.AssignLiteral("6");
-        tile.AssignLiteral("0");
+        style.Assign('6');
+        tile.Assign('0');
         break;
     }
 
@@ -1023,7 +1103,7 @@ nsWindowsShellService::OpenApplication(int32_t aApplication)
   ::RegCloseKey(theKey);
 
   // Find the "open" command
-  application.AppendLiteral("\\");
+  application.Append('\\');
   application.Append(buf);
   application.AppendLiteral("\\shell\\open\\command");
 
@@ -1122,8 +1202,7 @@ nsWindowsShellService::SetDesktopBackgroundColor(uint32_t aColor)
   return regKey->Close();
 }
 
-nsWindowsShellService::nsWindowsShellService() : 
-  mCheckedThisSession(false) 
+nsWindowsShellService::nsWindowsShellService()
 {
 }
 
diff --git a/application/palemoon/components/shell/nsWindowsShellService.h b/application/palemoon/components/shell/nsWindowsShellService.h
index f856ffd35..06c6c3c9b 100644
--- a/application/palemoon/components/shell/nsWindowsShellService.h
+++ b/application/palemoon/components/shell/nsWindowsShellService.h
@@ -16,9 +16,10 @@
 
 class nsWindowsShellService : public nsIWindowsShellService
 {
+  virtual ~nsWindowsShellService();
+
 public:
   nsWindowsShellService();
-  virtual ~nsWindowsShellService();
 
   NS_DECL_ISUPPORTS
   NS_DECL_NSISHELLSERVICE
@@ -26,12 +27,11 @@ public:
 
 protected:
   bool IsDefaultBrowserVista(bool aCheckAllTypes, bool* aIsDefaultBrowser);
+  nsresult LaunchControlPanelDefaultsSelectionUI();
   nsresult LaunchControlPanelDefaultPrograms();
   nsresult LaunchModernSettingsDialogDefaultApps();
+  nsresult InvokeHTTPOpenAsVerb();
   nsresult LaunchHTTPHandlerPane();
-
-private:
-  bool      mCheckedThisSession;
 };
 
 #endif // nswindowsshellservice_h____