Fix PDF generation – reset stream position

## Summary of the Pull Request

Theme aware cropped windows.

## PR Checklist
- [x] **Closes:** #28348
- [ ] **Communication:** I've discussed this with core contributors
already. If work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end user facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

## Detailed Description of the Pull Request / Additional comments

Added a Theme aware implementation that was already found on other
components, the only difference is that we are dealing with multiple
windows.
It will follow the Power Toys application theme, (windows too in case
PowerToys follows the System).
I decided to change the scope of a variable to not create a second
control of croppedWindows, this may need to be taken into consideration.

## Validation Steps Performed

Using Crop (Win + Ctrl + Shift +R)
Crop one or multiple windows.
All of them have the same theme as the application.
Went to windows theme settings, change to light theme, the app changes
accordingly.

Same behavior was tested with Thumbnail (Win  + Ctrl + Shift + T)

Closing windows and changing the theme again.

.github/actions/spell-check/expect.txt

@@ -1716,6 +1716,7 @@ trx
 tsa
 TSender
 TServer
+tskill
 tstoi
 TStr
 tweakme

src/modules/CropAndLock/CropAndLock/CropAndLock.vcxproj

@@ -154,6 +154,9 @@
     <ProjectReference Include="..\..\..\common\Telemetry\EtwTrace\EtwTrace.vcxproj">
       <Project>{8f021b46-362b-485c-bfba-ccf83e820cbd}</Project>
     </ProjectReference>
+    <ProjectReference Include="..\..\..\common\Themes\Themes.vcxproj">
+      <Project>{98537082-0fdb-40de-abd8-0dc5a4269bab}</Project>
+    </ProjectReference>
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <Import Project="..\..\..\..\deps\spdlog.props" />

src/modules/CropAndLock/CropAndLock/main.cpp

@@ -17,6 +17,9 @@
 
 #include <common/Telemetry/EtwTrace/EtwTrace.h>
 
+#include <common/Themes/theme_helpers.h>
+#include <common/Themes/theme_listener.h>
+
 #pragma comment(linker, "/manifestdependency:\"type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='*' publicKeyToken='6595b64144ccf1df' language='*'\"")
 
 namespace winrt
@@ -35,6 +38,23 @@ namespace util
 const std::wstring instanceMutexName = L"Local\\PowerToys_CropAndLock_InstanceMutex";
 bool m_running = true;
 
+// Theming
+ThemeListener theme_listener{};
+// Keep a list of our cropped windows
+std::vector<std::shared_ptr<CropAndLockWindow>> croppedWindows;
+
+void handleTheme()
+{
+    auto theme = theme_listener.AppTheme;
+    auto isDark = theme == Theme::Dark;
+    Logger::info(L"Theme is now {}", isDark ? L"Dark" : L"Light");
+    for (auto&& croppedWindow : croppedWindows)
+    {
+        ThemeHelpers::SetImmersiveDarkMode(croppedWindow->Handle(), isDark);
+    }
+}
+
+
 int WINAPI wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ PWSTR lpCmdLine, _In_ int)
 {
     // Initialize COM
@@ -42,6 +62,8 @@ int WINAPI wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ PWSTR lpCmdLine, _I
 
     Trace::CropAndLock::RegisterProvider();
 
+    theme_listener.AddChangedHandler(handleTheme);
+
     Shared::Trace::ETWTrace trace;
     trace.UpdateState(true);
 
@@ -107,8 +129,6 @@ int WINAPI wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ PWSTR lpCmdLine, _I
     // Create our overlay window
     std::unique_ptr<OverlayWindow> overlayWindow;
 
-    // Keep a list of our cropped windows
-    std::vector<std::shared_ptr<CropAndLockWindow>> croppedWindows;
 
     // Handles and thread for the events sent from runner
     HANDLE m_reparent_event_handle;
@@ -167,6 +187,7 @@ int WINAPI wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ PWSTR lpCmdLine, _I
             croppedWindow->CropAndLock(targetWindow, cropRect);
             croppedWindow->OnClosed(removeWindowCallback);
             croppedWindows.push_back(croppedWindow);
+            handleTheme();
         };
 
         overlayWindow.reset();

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.System/Helpers/Commands.cs

@@ -110,6 +110,13 @@ internal static class Commands
                 });
         }
 
+        results.Add(new ListItem(new ExecuteCommandConfirmation(Resources.Microsoft_plugin_sys_RestartShell_name!, confirmCommands, Resources.Microsoft_plugin_sys_RestartShell_confirmation!, static () => OpenInShellHelper.OpenInShell("cmd", "/C tskill explorer && start explorer", runWithHiddenWindow: true)))
+        {
+            Title = Resources.Microsoft_plugin_sys_RestartShell!,
+            Subtitle = Resources.Microsoft_plugin_sys_RestartShell_description!,
+            Icon = Icons.RestartShellIcon,
+        });
+
         // UEFI command/result. It is only available on systems booted in UEFI mode.
         if (isUefi)
         {

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.System/Helpers/Icons.cs

@@ -20,6 +20,8 @@ public static partial class Icons
 
     public static IconInfo RestartIcon { get; } = new IconInfo("\uE777");
 
+    public static IconInfo RestartShellIcon { get; } = new IconInfo("\uEC50");
+
     public static IconInfo ShutdownIcon { get; } = new IconInfo("\uE7E8");
 
     public static IconInfo SleepIcon { get; } = new IconInfo("\uE708");

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.System/Properties/Resources.Designer.cs

@@ -645,6 +645,42 @@ namespace Microsoft.CmdPal.Ext.System {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Restart Windows Explorer.
+        /// </summary>
+        public static string Microsoft_plugin_sys_RestartShell {
+            get {
+                return ResourceManager.GetString("Microsoft_plugin_sys_RestartShell", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to You are about to restart Windows Explorer, are you sure?.
+        /// </summary>
+        public static string Microsoft_plugin_sys_RestartShell_confirmation {
+            get {
+                return ResourceManager.GetString("Microsoft_plugin_sys_RestartShell_confirmation", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to End and restart the Windows Explorer shell process.
+        /// </summary>
+        public static string Microsoft_plugin_sys_RestartShell_description {
+            get {
+                return ResourceManager.GetString("Microsoft_plugin_sys_RestartShell_description", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Restart.
+        /// </summary>
+        public static string Microsoft_plugin_sys_RestartShell_name {
+            get {
+                return ResourceManager.GetString("Microsoft_plugin_sys_RestartShell_name", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to ip; mac; address.
         /// </summary>

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.System/Properties/Resources.resx

@@ -417,4 +417,16 @@
   <data name="Microsoft_plugin_ext_fallback_display_title" xml:space="preserve">
     <value>Open System Command</value>
   </data>
+  <data name="Microsoft_plugin_sys_RestartShell" xml:space="preserve">
+    <value>Restart Windows Explorer</value>
+  </data>
+  <data name="Microsoft_plugin_sys_RestartShell_description" xml:space="preserve">
+    <value>End and restart the Windows Explorer shell process</value>
+  </data>
+  <data name="Microsoft_plugin_sys_RestartShell_name" xml:space="preserve">
+    <value>Restart</value>
+  </data>
+  <data name="Microsoft_plugin_sys_RestartShell_confirmation" xml:space="preserve">
+    <value>You are about to restart Windows Explorer, are you sure?</value>
+  </data>
 </root>

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.TimeDate/FallbackTimeDateItem.cs

@@ -68,6 +68,7 @@ internal sealed partial class FallbackTimeDateItem : FallbackCommandItem
             Title = result.Title;
             Subtitle = result.Subtitle;
             Icon = result.Icon;
+            Command = result.Command;
         }
         else
         {

src/modules/previewpane/PdfPreviewHandler/PdfPreviewHandlerControl.cs

@@ -228,6 +228,8 @@ namespace Microsoft.PowerToys.PreviewHandler.Pdf
                     DestinationWidth = (uint)this.ClientSize.Width,
                 }).GetAwaiter().GetResult();
 
+                stream.Seek(0); // Reset the stream position to the beginning before reading.
+
                 imageOfPage = Image.FromStream(stream.AsStream());
             }
 

src/modules/registrypreview/RegistryPreviewUILib/RegistryPreviewMainPage.Events.cs

@@ -22,6 +22,10 @@ namespace RegistryPreviewUILib
     {
         private readonly DispatcherQueue _dispatcherQueue = DispatcherQueue.GetForCurrentThread();
 
+        // Indicator if we loaded/reloaded/saved a file and need to skip TextChanged event one time.
+        // (Solves the problem that enabling the event handler fires it one time.)
+        private static bool editorContentChangedScripted;
+
         /// <summary>
         /// Event that is will prevent the app from closing if the "save file" flag is active
         /// </summary>
@@ -76,6 +80,67 @@ namespace RegistryPreviewUILib
             MonacoEditor.Focus(FocusState.Programmatic);
         }
 
+        /// <summary>
+        /// New button action: Ask to save last changes and reset editor content to reg header only
+        /// </summary>
+        private async void NewButton_Click(object sender, RoutedEventArgs e)
+        {
+            // Check to see if the current file has been saved
+            if (saveButton.IsEnabled)
+            {
+                ContentDialog contentDialog = new ContentDialog()
+                {
+                    Title = resourceLoader.GetString("YesNoCancelDialogTitle"),
+                    Content = resourceLoader.GetString("YesNoCancelDialogContent"),
+                    PrimaryButtonText = resourceLoader.GetString("YesNoCancelDialogPrimaryButtonText"),
+                    SecondaryButtonText = resourceLoader.GetString("YesNoCancelDialogSecondaryButtonText"),
+                    CloseButtonText = resourceLoader.GetString("YesNoCancelDialogCloseButtonText"),
+                    DefaultButton = ContentDialogButton.Primary,
+                };
+
+                // Use this code to associate the dialog to the appropriate AppWindow by setting
+                // the dialog's XamlRoot to the same XamlRoot as an element that is already present in the AppWindow.
+                if (ApiInformation.IsApiContractPresent("Windows.Foundation.UniversalApiContract", 8))
+                {
+                    contentDialog.XamlRoot = this.Content.XamlRoot;
+                }
+
+                ContentDialogResult contentDialogResult = await contentDialog.ShowAsync();
+                switch (contentDialogResult)
+                {
+                    case ContentDialogResult.Primary:
+                        // Save, then continue the new action
+                        if (!AskFileName(string.Empty) ||
+                            !SaveFile())
+                        {
+                            return;
+                        }
+
+                        break;
+                    case ContentDialogResult.Secondary:
+                        // Don't save and continue the new action!
+                        break;
+                    default:
+                        // Don't open the new action!
+                        return;
+                }
+            }
+
+            // mute the TextChanged handler to make for clean UI
+            MonacoEditor.TextChanged -= MonacoEditor_TextChanged;
+
+            // reset editor, file info and ui.
+            _appFileName = string.Empty;
+            ResetEditorAndFile();
+
+            // disable buttons that do not make sense
+            UpdateUnsavedFileState(false);
+            refreshButton.IsEnabled = false;
+
+            // restore the TextChanged handler
+            ButtonAction_RestoreTextChangedEvent();
+        }
+
         /// <summary>
         /// Uses a picker to select a new file to open
         /// </summary>
@@ -106,11 +171,15 @@ namespace RegistryPreviewUILib
                 {
                     case ContentDialogResult.Primary:
                         // Save, then continue the file open
-                        SaveFile();
+                        if (!AskFileName(string.Empty) ||
+                            !SaveFile())
+                        {
+                            return;
+                        }
+
                         break;
                     case ContentDialogResult.Secondary:
                         // Don't save and continue the file open!
-                        saveButton.IsEnabled = false;
                         break;
                     default:
                         // Don't open the new file!
@@ -137,14 +206,16 @@ namespace RegistryPreviewUILib
             {
                 // mute the TextChanged handler to make for clean UI
                 MonacoEditor.TextChanged -= MonacoEditor_TextChanged;
+
+                // update file name
                 _appFileName = storageFile.Path;
                 UpdateToolBarAndUI(await OpenRegistryFile(_appFileName));
 
                 // disable the Save button as it's a new file
-                saveButton.IsEnabled = false;
+                UpdateUnsavedFileState(false);
 
                 // Restore the event handler as we're loaded
-                MonacoEditor.TextChanged += MonacoEditor_TextChanged;
+                ButtonAction_RestoreTextChangedEvent();
             }
         }
 
@@ -153,7 +224,14 @@ namespace RegistryPreviewUILib
         /// </summary>
         private void SaveButton_Click(object sender, RoutedEventArgs e)
         {
-            SaveFile();
+            if (!AskFileName(string.Empty))
+            {
+                return;
+            }
+
+            // save and update window title
+            // error handling and ui update happens in SaveFile() method
+            _ = SaveFile();
         }
 
         /// <summary>
@@ -161,47 +239,24 @@ namespace RegistryPreviewUILib
         /// </summary>
         private async void SaveAsButton_Click(object sender, RoutedEventArgs e)
         {
-            // Save out a new REG file and then open it - we have to use the direct Win32 method because FileOpenPicker crashes when it's
-            // called while running as admin
-            IntPtr windowHandle = WinRT.Interop.WindowNative.GetWindowHandle(_mainWindow);
-            string filename = SaveFilePicker.ShowDialog(
-                windowHandle,
-                resourceLoader.GetString("SuggestFileName"),
-                resourceLoader.GetString("FilterRegistryName") + '\0' + "*.reg" + '\0' + resourceLoader.GetString("FilterAllFiles") + '\0' + "*.*" + '\0' + '\0',
-                resourceLoader.GetString("SaveDialogTitle"));
+            // mute the TextChanged handler to make for clean UI
+            MonacoEditor.TextChanged -= MonacoEditor_TextChanged;
 
-            if (filename == string.Empty)
+            if (!AskFileName(_appFileName) || !SaveFile())
             {
                 return;
             }
 
-            _appFileName = filename;
-            SaveFile();
             UpdateToolBarAndUI(await OpenRegistryFile(_appFileName));
+
+            // restore the TextChanged handler
+            ButtonAction_RestoreTextChangedEvent();
         }
 
         /// <summary>
         /// Reloads the current REG file from storage
         /// </summary>
         private async void RefreshButton_Click(object sender, RoutedEventArgs e)
-        {
-            // mute the TextChanged handler to make for clean UI
-            MonacoEditor.TextChanged -= MonacoEditor_TextChanged;
-
-            // reload the current Registry file and update the toolbar accordingly.
-            UpdateToolBarAndUI(await OpenRegistryFile(_appFileName), true, true);
-
-            // disable the Save button as it's a new file
-            saveButton.IsEnabled = false;
-
-            // restore the TextChanged handler
-            MonacoEditor.TextChanged += MonacoEditor_TextChanged;
-        }
-
-        /// <summary>
-        /// Resets the editor content
-        /// </summary>
-        private async void NewButton_Click(object sender, RoutedEventArgs e)
         {
             // Check to see if the current file has been saved
             if (saveButton.IsEnabled)
@@ -209,10 +264,9 @@ namespace RegistryPreviewUILib
                 ContentDialog contentDialog = new ContentDialog()
                 {
                     Title = resourceLoader.GetString("YesNoCancelDialogTitle"),
-                    Content = resourceLoader.GetString("YesNoCancelDialogContent"),
-                    PrimaryButtonText = resourceLoader.GetString("YesNoCancelDialogPrimaryButtonText"),
-                    SecondaryButtonText = resourceLoader.GetString("YesNoCancelDialogSecondaryButtonText"),
-                    CloseButtonText = resourceLoader.GetString("YesNoCancelDialogCloseButtonText"),
+                    Content = resourceLoader.GetString("ReloadDialogContent"),
+                    PrimaryButtonText = resourceLoader.GetString("ReloadDialogPrimaryButtonText"),
+                    CloseButtonText = resourceLoader.GetString("ReloadDialogCloseButtonText"),
                     DefaultButton = ContentDialogButton.Primary,
                 };
 
@@ -227,15 +281,10 @@ namespace RegistryPreviewUILib
                 switch (contentDialogResult)
                 {
                     case ContentDialogResult.Primary:
-                        // Save, then continue the file open
-                        SaveFile();
-                        break;
-                    case ContentDialogResult.Secondary:
-                        // Don't save and continue the file open!
-                        saveButton.IsEnabled = false;
+                        // Don't save and continue the reload action!
                         break;
                     default:
-                        // Don't open the new file!
+                        // Don't continue the reload action!
                         return;
                 }
             }
@@ -243,16 +292,14 @@ namespace RegistryPreviewUILib
             // mute the TextChanged handler to make for clean UI
             MonacoEditor.TextChanged -= MonacoEditor_TextChanged;
 
-            // reset editor, file info and ui.
-            _appFileName = string.Empty;
-            ResetEditorAndFile();
+            // reload the current Registry file and update the toolbar accordingly.
+            UpdateToolBarAndUI(await OpenRegistryFile(_appFileName), true, true);
+
+            // disable the Save button as it's a new file
+            UpdateUnsavedFileState(false);
 
             // restore the TextChanged handler
-            MonacoEditor.TextChanged += MonacoEditor_TextChanged;
-
-            // disable buttons that do not make sense
-            saveButton.IsEnabled = false;
-            refreshButton.IsEnabled = false;
+            ButtonAction_RestoreTextChangedEvent();
         }
 
         /// <summary>
@@ -313,15 +360,20 @@ namespace RegistryPreviewUILib
                 switch (contentDialogResult)
                 {
                     case ContentDialogResult.Primary:
-                        // Save, then continue the file open
-                        SaveFile();
+                        // Save, then continue the merge action
+                        if (!AskFileName(string.Empty) ||
+                            !SaveFile())
+                        {
+                            return;
+                        }
+
                         break;
                     case ContentDialogResult.Secondary:
-                        // Don't save and continue the file open!
-                        saveButton.IsEnabled = false;
+                        // Don't save and continue the merge action!
+                        UpdateUnsavedFileState(false);
                         break;
                     default:
-                        // Don't open the new file!
+                        // Don't merge the file!
                         return;
                 }
             }
@@ -411,10 +463,29 @@ namespace RegistryPreviewUILib
             _dispatcherQueue.TryEnqueue(() =>
             {
                 RefreshRegistryFile();
-                saveButton.IsEnabled = true;
+                if (!editorContentChangedScripted)
+                {
+                    UpdateUnsavedFileState(true);
+                }
+
+                editorContentChangedScripted = false;
             });
         }
 
+        /// <summary>
+        /// Sets indicator for programatic text change and adds text changed handler
+        /// </summary>
+        /// <remarks>
+        /// Use this always, if button actions temporary disable the text changed event
+        /// </remarks>
+        private void ButtonAction_RestoreTextChangedEvent()
+        {
+            // Solves the problem that enabling the event handler fires it one time.
+            // These one time fired event would causes wrong unsaved changes state.
+            editorContentChangedScripted = true;
+            MonacoEditor.TextChanged += MonacoEditor_TextChanged;
+        }
+
         // Commands to show data preview
         public void ButtonExtendedPreview_Click(object sender, RoutedEventArgs e)
         {

src/modules/registrypreview/RegistryPreviewUILib/RegistryPreviewMainPage.Utilities.cs

@@ -11,6 +11,7 @@ using System.IO;
 using System.Linq;
 using System.Reflection;
 using System.Text;
+using System.Text.RegularExpressions;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.UI.Input;
@@ -24,7 +25,10 @@ namespace RegistryPreviewUILib
     {
         private const string NEWFILEHEADER = "Windows Registry Editor Version 5.00\r\n\r\n";
 
+        private static readonly string _unsavedFileIndicator = "* ";
+        private static readonly char[] _unsavedFileIndicatorChars = [' ', '*'];
         private static SemaphoreSlim _dialogSemaphore = new(1);
+
         private string lastKeyPath;
 
         public delegate void UpdateWindowTitleFunction(string title);
@@ -832,42 +836,66 @@ namespace RegistryPreviewUILib
         /// </summary>
         private async void HandleDirtyClosing(string title, string content, string primaryButtonText, string secondaryButtonText, string closeButtonText)
         {
-            ContentDialog contentDialog = new ContentDialog()
+            if (_dialogSemaphore.CurrentCount == 0)
             {
-                Title = title,
-                Content = content,
-                PrimaryButtonText = primaryButtonText,
-                SecondaryButtonText = secondaryButtonText,
-                CloseButtonText = closeButtonText,
-                DefaultButton = ContentDialogButton.Primary,
-            };
-
-            // Use this code to associate the dialog to the appropriate AppWindow by setting
-            // the dialog's XamlRoot to the same XamlRoot as an element that is already present in the AppWindow.
-            if (ApiInformation.IsApiContractPresent("Windows.Foundation.UniversalApiContract", 8))
-            {
-                contentDialog.XamlRoot = this.Content.XamlRoot;
+                return;
             }
 
-            ContentDialogResult contentDialogResult = await contentDialog.ShowAsync();
-
-            switch (contentDialogResult)
+            try
             {
-                case ContentDialogResult.Primary:
-                    // Save, then close
-                    SaveFile();
-                    break;
-                case ContentDialogResult.Secondary:
-                    // Don't save, and then close!
-                    saveButton.IsEnabled = false;
-                    break;
-                default:
-                    // Cancel closing!
-                    return;
-            }
+                await _dialogSemaphore.WaitAsync();
 
-            // if we got here, we should try to close again
-            Application.Current.Exit();
+                ContentDialog contentDialog = new ContentDialog()
+                {
+                    Title = title,
+                    Content = content,
+                    PrimaryButtonText = primaryButtonText,
+                    SecondaryButtonText = secondaryButtonText,
+                    CloseButtonText = closeButtonText,
+                    DefaultButton = ContentDialogButton.Primary,
+                };
+
+                // Use this code to associate the dialog to the appropriate AppWindow by setting
+                // the dialog's XamlRoot to the same XamlRoot as an element that is already present in the AppWindow.
+                if (ApiInformation.IsApiContractPresent("Windows.Foundation.UniversalApiContract", 8))
+                {
+                    contentDialog.XamlRoot = this.Content.XamlRoot;
+                }
+
+                ContentDialogResult contentDialogResult = await contentDialog.ShowAsync();
+
+                switch (contentDialogResult)
+                {
+                    case ContentDialogResult.Primary:
+                        // Save, then close
+                        if (!AskFileName(string.Empty) ||
+                            !SaveFile())
+                        {
+                            return;
+                        }
+
+                        break;
+                    case ContentDialogResult.Secondary:
+                        // Don't save, and then close!
+                        UpdateUnsavedFileState(false);
+                        break;
+                    default:
+                        // Cancel closing!
+                        return;
+                }
+
+                // if we got here, we should try to close again
+                Application.Current.Exit();
+            }
+            catch
+            {
+                // Normally nothing to catch here.
+                // But for safety the try-catch ensures that we always release the content dialog lock and exit correctly.
+            }
+            finally
+            {
+                _dialogSemaphore.Release();
+            }
         }
 
         /// <summary>
@@ -927,11 +955,71 @@ namespace RegistryPreviewUILib
             type.InvokeMember("ProtectedCursor", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.SetProperty | BindingFlags.Instance, null, uiElement, new object[] { cursor }, CultureInfo.InvariantCulture);
         }
 
+        public void UpdateUnsavedFileState(bool unsavedChanges)
+        {
+            // get, cut and analyze the current title
+            string currentTitle = Regex.Replace(_mainWindow.Title, APPNAME + @"$|\s-\s" + APPNAME + @"$", string.Empty);
+            bool titleContainsIndicator = currentTitle.StartsWith(_unsavedFileIndicator, StringComparison.CurrentCultureIgnoreCase);
+
+            // update window title and save button state
+            if (unsavedChanges)
+            {
+                saveButton.IsEnabled = true;
+
+                if (!titleContainsIndicator)
+                {
+                    _updateWindowTitleFunction(_unsavedFileIndicator + currentTitle);
+                }
+            }
+            else
+            {
+                saveButton.IsEnabled = false;
+
+                if (titleContainsIndicator)
+                {
+                    _updateWindowTitleFunction(currentTitle.TrimStart(_unsavedFileIndicatorChars));
+                }
+            }
+        }
+
+        /// <summary>
+        /// Ask the user for the file path if it is unknown because of an unsaved file
+        /// </summary>
+        /// <param name="fileName">If not empty always ask for a file path and use the value as name.</param>
+        /// <returns>Returns true if user selected a path, otherwise false</returns>
+        public bool AskFileName(string fileName)
+        {
+            if (string.IsNullOrEmpty(_appFileName) || !string.IsNullOrEmpty(fileName) )
+            {
+                string fName = string.IsNullOrEmpty(fileName) ? resourceLoader.GetString("SuggestFileName") : fileName;
+
+                // Save out a new REG file and then open it - we have to use the direct Win32 method because FileOpenPicker crashes when it's
+                // called while running as admin
+                IntPtr windowHandle = WinRT.Interop.WindowNative.GetWindowHandle(_mainWindow);
+                string filename = SaveFilePicker.ShowDialog(
+                    windowHandle,
+                    fName,
+                    resourceLoader.GetString("FilterRegistryName") + '\0' + "*.reg" + '\0' + resourceLoader.GetString("FilterAllFiles") + '\0' + "*.*" + '\0' + '\0',
+                    resourceLoader.GetString("SaveDialogTitle"));
+
+                if (filename == string.Empty)
+                {
+                    return false;
+                }
+
+                _appFileName = filename;
+            }
+
+            return true;
+        }
+
         /// <summary>
         /// Wrapper method that saves the current file in place, using the current text in editor.
         /// </summary>
-        private void SaveFile()
+        private bool SaveFile()
         {
+            bool saveSuccess = true;
+
             ChangeCursor(gridPreview, true);
 
             // set up the FileStream for all writing
@@ -955,10 +1043,13 @@ namespace RegistryPreviewUILib
                 streamWriter.Close();
 
                 // only change when the save is successful
-                saveButton.IsEnabled = false;
+                UpdateUnsavedFileState(false);
+                _updateWindowTitleFunction(_appFileName);
             }
             catch (UnauthorizedAccessException ex)
             {
+                saveSuccess = false;
+
                 // this exception is thrown if the file is there but marked as read only
                 ShowMessageBox(
                     resourceLoader.GetString("ErrorDialogTitle"),
@@ -967,6 +1058,8 @@ namespace RegistryPreviewUILib
             }
             catch
             {
+                saveSuccess = false;
+
                 // this catch handles all other exceptions thrown when trying to write the file out
                 ShowMessageBox(
                     resourceLoader.GetString("ErrorDialogTitle"),
@@ -984,6 +1077,8 @@ namespace RegistryPreviewUILib
 
             // restore the cursor
             ChangeCursor(gridPreview, false);
+
+            return saveSuccess;
         }
 
         /// <summary>

src/modules/registrypreview/RegistryPreviewUILib/Strings/en-US/Resources.resw

@@ -258,12 +258,18 @@
   <data name="YesNoCancelDialogCloseButtonText" xml:space="preserve">
     <value>Cancel</value>
   </data>
+  <data name="ReloadDialogCloseButtonText" xml:space="preserve">
+    <value>No</value>
+  </data>
   <data name="YesNoCancelDialogContent" xml:space="preserve">
     <value>Save changes?</value>
   </data>
   <data name="YesNoCancelDialogPrimaryButtonText" xml:space="preserve">
     <value>Save</value>
   </data>
+  <data name="ReloadDialogPrimaryButtonText" xml:space="preserve">
+    <value>Yes</value>
+  </data>
   <data name="YesNoCancelDialogSecondaryButtonText" xml:space="preserve">
     <value>Don't save</value>
   </data>
@@ -363,4 +369,7 @@
   <data name="NewButton.Label" xml:space="preserve">
     <value>New</value>
   </data>
+  <data name="ReloadDialogContent" xml:space="preserve">
+    <value>You lose any unsaved changes. Reload anyway?</value>
+  </data>
 </root>