--- a/toolkit/xre/nsAppRunner.cpp
+++ b/toolkit/xre/nsAppRunner.cpp
@@ -1879,17 +1879,57 @@ XRE_GetBinaryPath(nsIFile* *aResult)
   return mozilla::BinaryPath::GetFile(aResult);
 }
 
 #ifdef XP_WIN
 #include "nsWindowsRestart.cpp"
 #include <shellapi.h>
 
 typedef BOOL (WINAPI* SetProcessDEPPolicyFunc)(DWORD dwFlags);
-#endif
+
+static void
+RegisterApplicationRestartChanged(const char* aPref, void* aData) {
+  DWORD cchCmdLine = 0;
+  HRESULT rc =
+    ::GetApplicationRestartSettings(::GetCurrentProcess(), nullptr, &cchCmdLine, nullptr);
+  bool wasRegistered = false;
+  if (rc == S_OK) {
+    wasRegistered = true;
+  }
+
+  if (Preferences::GetBool(PREF_WIN_REGISTER_APPLICATION_RESTART, false) && !wasRegistered) {
+    // Make the command line to use when restarting
+    wchar_t* restartCommandLine = nullptr;
+    if (gRestartArgc > 1) {
+      // excludes argv[0] because RegisterApplicationRestart adds the
+      // executable name
+      wchar_t** restartArgvConverted =
+        AllocConvertUTF8toUTF16Strings(gRestartArgc - 1, gRestartArgv + 1);
+
+      if (restartArgvConverted) {
+        restartCommandLine = MakeCommandLine(gRestartArgc - 1, restartArgvConverted);
+        FreeAllocStrings(gRestartArgc - 1, restartArgvConverted);
+      }
+    } else {
+      restartCommandLine = (wchar_t*) malloc(sizeof(wchar_t));
+      restartCommandLine[0] = L'\0';
+    }
+
+    if (restartCommandLine) {
+      // Flags RESTART_NO_PATCH and RESTART_NO_REBOOT are not set, so we
+      // should be restarted if terminated by an update or restart.
+      ::RegisterApplicationRestart(restartCommandLine, RESTART_NO_CRASH |
+                                                       RESTART_NO_HANG);
+      free(restartCommandLine);
+    }
+  } else if (wasRegistered) {
+    ::UnregisterApplicationRestart();
+  }
+}
+#endif // XP_WIN
 
 // If aBlankCommandLine is true, then the application will be launched with a
 // blank command line instead of being launched with the same command line that
 // it was initially started with.
 static nsresult LaunchChild(nsINativeAppSupport* aNative,
                             bool aBlankCommandLine = false)
 {
   aNative->Quit(); // release DDE mutex, if we're holding it
@@ -4730,16 +4770,21 @@ XREMain::XRE_mainRun()
   SaveToEnv("NO_EM_RESTART=");
   SaveToEnv("XUL_APP_FILE=");
   SaveToEnv("XRE_BINARY_PATH=");
 
   if (!mShuttingDown) {
     rv = appStartup->CreateHiddenWindow();
     NS_ENSURE_SUCCESS(rv, NS_ERROR_FAILURE);
 
+#ifdef XP_WIN32
+    Preferences::RegisterCallbackAndCall(RegisterApplicationRestartChanged,
+                                         PREF_WIN_REGISTER_APPLICATION_RESTART);
+#endif
+
 #if defined(HAVE_DESKTOP_STARTUP_ID) && defined(MOZ_WIDGET_GTK)
     nsGTKToolkit* toolkit = nsGTKToolkit::GetToolkit();
     if (toolkit && !mDesktopStartupID.IsEmpty()) {
       toolkit->SetDesktopStartupID(mDesktopStartupID);
     }
     // Clear the environment variable so it won't be inherited by
     // child processes and confuse things.
     g_unsetenv ("DESKTOP_STARTUP_ID");

--- a/toolkit/xre/nsAppRunner.h
+++ b/toolkit/xre/nsAppRunner.h
@@ -105,16 +105,18 @@ MozExpectedExit();
 #ifdef XP_WIN
 void
 UseParentConsole();
 
 BOOL
 WinLaunchChild(const wchar_t *exePath, int argc,
                char **argv, HANDLE userToken = nullptr,
                HANDLE *hProcess = nullptr);
+
+#define PREF_WIN_REGISTER_APPLICATION_RESTART "toolkit.winRegisterApplicationRestart"
 #endif
 
 #define NS_NATIVEAPPSUPPORT_CONTRACTID "@mozilla.org/toolkit/native-app-support;1"
 
 namespace mozilla {
 namespace startup {
 Result<nsCOMPtr<nsIFile>, nsresult> GetIncompleteStartupFile(nsIFile* aProfLD);
 

--- a/toolkit/xre/nsWindowsRestart.cpp
+++ b/toolkit/xre/nsWindowsRestart.cpp
@@ -108,18 +108,16 @@ static wchar_t* ArgToString(wchar_t *d, 
   }
 
   return d;
 }
 
 /**
  * Creates a command line from a list of arguments. The returned
  * string is allocated with "malloc" and should be "free"d.
- *
- * argv is UTF8
  */
 wchar_t*
 MakeCommandLine(int argc, wchar_t **argv)
 {
   int i;
   int len = 0;
 
   // The + 1 of the last argument handles the allocation for null termination
@@ -173,16 +171,32 @@ FreeAllocStrings(int argc, wchar_t **arg
   while (argc) {
     --argc;
     delete [] argv[argc];
   }
 
   delete [] argv;
 }
 
+static wchar_t**
+AllocConvertUTF8toUTF16Strings(int argc, char **argv)
+{
+  wchar_t **argvConverted = new wchar_t*[argc];
+  if (!argvConverted)
+    return nullptr;
+
+  for (int i = 0; i < argc; ++i) {
+    argvConverted[i] = reinterpret_cast<wchar_t*>(AllocConvertUTF8toUTF16(argv[i]));
+    if (!argvConverted[i]) {
+      FreeAllocStrings(i, argvConverted);
+      return nullptr;
+    }
+  }
+  return argvConverted;
+}
 
 
 /**
  * Launch a child process with the specified arguments.
  * @note argv[0] is ignored
  * @note The form of this function that takes char **argv expects UTF-8
  */
 
@@ -193,28 +207,20 @@ WinLaunchChild(const wchar_t *exePath,
                HANDLE *hProcess = nullptr);
 
 BOOL
 WinLaunchChild(const wchar_t *exePath,
                int argc, char **argv,
                HANDLE userToken,
                HANDLE *hProcess)
 {
-  wchar_t** argvConverted = new wchar_t*[argc];
+  wchar_t **argvConverted = AllocConvertUTF8toUTF16Strings(argc, argv);
   if (!argvConverted)
     return FALSE;
 
-  for (int i = 0; i < argc; ++i) {
-      argvConverted[i] = reinterpret_cast<wchar_t*>(AllocConvertUTF8toUTF16(argv[i]));
-    if (!argvConverted[i]) {
-      FreeAllocStrings(i, argvConverted);
-      return FALSE;
-    }
-  }
-
   BOOL ok = WinLaunchChild(exePath, argc, argvConverted, userToken, hProcess);
   FreeAllocStrings(argc, argvConverted);
   return ok;
 }
 
 BOOL
 WinLaunchChild(const wchar_t *exePath,
                int argc,

--- a/widget/windows/ScreenHelperWin.cpp
+++ b/widget/windows/ScreenHelperWin.cpp
@@ -11,48 +11,57 @@
 #include "WinUtils.h"
 
 static mozilla::LazyLogModule sScreenLog("WidgetScreen");
 
 namespace mozilla {
 namespace widget {
 
 BOOL CALLBACK
-CollectMonitors(HMONITOR aMon, HDC hDCScreen, LPRECT, LPARAM ioParam)
+CollectMonitors(HMONITOR aMon, HDC, LPRECT, LPARAM ioParam)
 {
   auto screens = reinterpret_cast<nsTArray<RefPtr<Screen>>*>(ioParam);
   BOOL success = FALSE;
-  MONITORINFO info;
-  info.cbSize = sizeof(MONITORINFO);
+  MONITORINFOEX info;
+  info.cbSize = sizeof(MONITORINFOEX);
   success = ::GetMonitorInfoW(aMon, &info);
   if (!success) {
     MOZ_LOG(sScreenLog, LogLevel::Error, ("GetMonitorInfoW failed"));
     return TRUE; // continue the enumeration
   }
+
   double scale = WinUtils::LogToPhysFactor(aMon);
   DesktopToLayoutDeviceScale contentsScaleFactor;
   if (WinUtils::IsPerMonitorDPIAware()) {
     contentsScaleFactor.scale = 1.0;
   } else {
     contentsScaleFactor.scale = scale;
   }
   CSSToLayoutDeviceScale defaultCssScaleFactor(scale);
   LayoutDeviceIntRect rect(info.rcMonitor.left, info.rcMonitor.top,
                            info.rcMonitor.right - info.rcMonitor.left,
                            info.rcMonitor.bottom - info.rcMonitor.top);
   LayoutDeviceIntRect availRect(info.rcWork.left, info.rcWork.top,
                                 info.rcWork.right - info.rcWork.left,
                                 info.rcWork.bottom - info.rcWork.top);
-  uint32_t pixelDepth = ::GetDeviceCaps(hDCScreen, BITSPIXEL);
+
+  HDC hDC = CreateDC(nullptr, info.szDevice, nullptr, nullptr);
+  if (!hDC) {
+    MOZ_LOG(sScreenLog, LogLevel::Error, ("CollectMonitors CreateDC failed"));
+    return TRUE;
+  }
+  uint32_t pixelDepth = ::GetDeviceCaps(hDC, BITSPIXEL);
+  DeleteDC(hDC);
   if (pixelDepth == 32) {
     // If a device uses 32 bits per pixel, it's still only using 8 bits
     // per color component, which is what our callers want to know.
     // (Some devices report 32 and some devices report 24.)
     pixelDepth = 24;
   }
+
   float dpi = WinUtils::MonitorDPI(aMon);
   MOZ_LOG(sScreenLog, LogLevel::Debug,
            ("New screen [%d %d %d %d (%d %d %d %d) %d %f %f %f]",
             rect.X(), rect.Y(), rect.Width(), rect.Height(),
             availRect.X(), availRect.Y(), availRect.Width(), availRect.Height(),
             pixelDepth, contentsScaleFactor.scale, defaultCssScaleFactor.scale,
             dpi));
   auto screen = new Screen(rect, availRect,
@@ -69,22 +78,19 @@ CollectMonitors(HMONITOR aMon, HDC hDCSc
 }
 
 void
 ScreenHelperWin::RefreshScreens()
 {
   MOZ_LOG(sScreenLog, LogLevel::Debug, ("Refreshing screens"));
 
   AutoTArray<RefPtr<Screen>, 4> screens;
-  HDC hdc = ::CreateDC(L"DISPLAY", nullptr, nullptr, nullptr);
-  NS_ASSERTION(hdc,"CreateDC Failure");
-  BOOL result = ::EnumDisplayMonitors(hdc, nullptr,
+  BOOL result = ::EnumDisplayMonitors(nullptr, nullptr,
                                       (MONITORENUMPROC)CollectMonitors,
                                       (LPARAM)&screens);
-  ::DeleteDC(hdc);
   if (!result) {
     NS_WARNING("Unable to EnumDisplayMonitors");
   }
   ScreenManager& screenManager = ScreenManager::GetSingleton();
   screenManager.Refresh(Move(screens));
 }
 
 } // namespace widget

--- a/widget/windows/nsWindow.cpp
+++ b/widget/windows/nsWindow.cpp
@@ -65,16 +65,17 @@
 #include "mozilla/MouseEvents.h"
 #include "mozilla/TouchEvents.h"
 
 #include "mozilla/ipc/MessageChannel.h"
 #include <algorithm>
 #include <limits>
 
 #include "nsWindow.h"
+#include "nsAppRunner.h"
 
 #include <shellapi.h>
 #include <windows.h>
 #include <wtsapi32.h>
 #include <process.h>
 #include <commctrl.h>
 #include <unknwn.h>
 #include <psapi.h>
@@ -5152,16 +5153,33 @@ ExitThisProcessSafely()
   HANDLE process = GetCurrentProcess();
   if (TerminateProcess(GetCurrentProcess(), 0)) {
     // TerminateProcess is asynchronous, so we wait on our own process handle
     WaitForSingleObject(process, INFINITE);
   }
   MOZ_CRASH("Just in case extremis crash in ExitThisProcessSafely.");
 }
 
+const char16_t*
+GetQuitType()
+{
+  if (Preferences::GetBool(PREF_WIN_REGISTER_APPLICATION_RESTART, false)) {
+    DWORD cchCmdLine = 0;
+    HRESULT rc =
+      ::GetApplicationRestartSettings(::GetCurrentProcess(), nullptr, &cchCmdLine, nullptr);
+    if (rc == S_OK) {
+      return u"restart";
+    } else {
+      return nullptr;
+    }
+  } else {
+    return nullptr;
+  }
+}
+
 // The main windows message processing method.
 bool
 nsWindow::ProcessMessage(UINT msg, WPARAM& wParam, LPARAM& lParam,
                          LRESULT *aRetValue)
 {
 #if defined(EVENT_DEBUG_OUTPUT)
   // First param shows all events, second param indicates whether
   // to show mouse move events. See nsWindowDbg for details.
@@ -5197,17 +5215,19 @@ nsWindow::ProcessMessage(UINT msg, WPARA
       {
         // Ask if it's ok to quit, and store the answer until we
         // get WM_ENDSESSION signaling the round is complete.
         nsCOMPtr<nsIObserverService> obsServ =
           mozilla::services::GetObserverService();
         nsCOMPtr<nsISupportsPRBool> cancelQuit =
           do_CreateInstance(NS_SUPPORTS_PRBOOL_CONTRACTID);
         cancelQuit->SetData(false);
-        obsServ->NotifyObservers(cancelQuit, "quit-application-requested", nullptr);
+
+        const char16_t* quitType = GetQuitType();;
+        obsServ->NotifyObservers(cancelQuit, "quit-application-requested", quitType);
 
         bool abortQuit;
         cancelQuit->GetData(&abortQuit);
         sCanQuit = abortQuit ? TRI_FALSE : TRI_TRUE;
       }
       *aRetValue = sCanQuit ? TRUE : FALSE;
       result = true;
       break;
@@ -5228,19 +5248,21 @@ nsWindow::ProcessMessage(UINT msg, WPARA
         // Let's fake a shutdown sequence without actually closing windows etc.
         // to avoid Windows killing us in the middle. A proper shutdown would
         // require having a chance to pump some messages. Unfortunately
         // Windows won't let us do that. Bug 212316.
         nsCOMPtr<nsIObserverService> obsServ =
           mozilla::services::GetObserverService();
         const char16_t* context = u"shutdown-persist";
         const char16_t* syncShutdown = u"syncShutdown";
+        const char16_t* quitType = GetQuitType();
+
         obsServ->NotifyObservers(nullptr, "quit-application-granted", syncShutdown);
         obsServ->NotifyObservers(nullptr, "quit-application-forced", nullptr);
-        obsServ->NotifyObservers(nullptr, "quit-application", nullptr);
+        obsServ->NotifyObservers(nullptr, "quit-application", quitType);
         obsServ->NotifyObservers(nullptr, "profile-change-net-teardown", context);
         obsServ->NotifyObservers(nullptr, "profile-change-teardown", context);
         obsServ->NotifyObservers(nullptr, "profile-before-change", context);
         obsServ->NotifyObservers(nullptr, "profile-before-change-qm", context);
         obsServ->NotifyObservers(nullptr, "profile-before-change-telemetry", context);
         ExitThisProcessSafely();
       }
       sCanQuit = TRI_UNKNOWN;