fix bug

This avoids the few frames of "flicker in" that XAML does when the window is SW_SHOW'n

closes #38384
closes #38404
closes #38438

.pipelines/v2/templates/job-build-project.yml

@@ -344,6 +344,11 @@ jobs:
       flattenFolders: True
       OverWrite: True
 
+  # Check if all projects (located in src sub-folder) import common props
+  - pwsh: |-
+      & '.pipelines/verifyCommonProps.ps1' -sourceDir '$(build.sourcesdirectory)\src'
+    displayName: Audit shared common props for CSharp projects in src sub-folder
+
   # Check if deps.json files don't reference different dll versions.
   - pwsh: |-
       & '.pipelines/verifyDepsJsonLibraryVersions.ps1' -targetDir '$(build.sourcesdirectory)\$(BuildPlatform)\$(BuildConfiguration)'

.pipelines/verifyCommonProps.ps1

@@ -0,0 +1,54 @@
+[CmdletBinding()]
+Param(
+    [Parameter(Mandatory = $True, Position = 1)]
+    [string]$sourceDir
+)
+
+# scan all csharp project in the source directory
+function Get-CSharpProjects {
+    param (
+        [string]$path
+    )
+
+    # Get all .csproj files under the specified path
+    return Get-ChildItem -Path $path -Recurse -Filter *.csproj | Select-Object -ExpandProperty FullName
+}
+
+# Check if the project file imports 'Common.Dotnet.CsWinRT.props'
+function Test-ImportSharedCsWinRTProps {
+    param (
+        [string]$filePath
+    )
+
+    # Load the XML content of the .csproj file
+    [xml]$csprojContent = Get-Content -Path $filePath
+
+    
+    # Check if the Import element with Project attribute containing 'Common.Dotnet.CsWinRT.props' exists
+    return $csprojContent.Project.Import | Where-Object { $null -ne $_.Project -and $_.Project.EndsWith('Common.Dotnet.CsWinRT.props') }
+}
+
+# Call the function with the provided source directory
+$csprojFilesArray = Get-CSharpProjects -path $sourceDir
+
+$hasInvalidCsProj = $false
+
+# Enumerate the array of file paths and call Validate-ImportSharedCsWinRTProps for each file
+foreach ($csprojFile in $csprojFilesArray) {
+    # Skip if the file ends with 'TemplateCmdPalExtension.csproj'
+    if ($csprojFile -like '*TemplateCmdPalExtension.csproj') {
+        continue
+    }
+
+    $importExists = Test-ImportSharedCsWinRTProps -filePath $csprojFile
+    if (!$importExists) {
+        Write-Output "$csprojFile need to import 'Common.Dotnet.CsWinRT.props'."
+        $hasInvalidCsProj = $true
+    }
+}
+
+if ($hasInvalidCsProj) {
+    exit 1
+}
+
+exit 0

src/Common.Dotnet.FuzzTest.props

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Some items may be set in Directory.Build.props in root -->
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <!-- OneFuzz does not currently support testing with .NET 9.
+       As a temporary workaround, create a .NET 8 project and use file links 
+       to include the code that needs testing. -->
+  <PropertyGroup>
+    <TargetFramework>net8.0-windows10.0.19041.0</TargetFramework>
+  </PropertyGroup>
+</Project>

src/modules/AdvancedPaste/AdvancedPaste.FuzzTests/AdvancedPaste.FuzzTests.csproj

@@ -1,6 +1,8 @@
 <Project Sdk="Microsoft.NET.Sdk">
+	<!-- Look at Directory.Build.props in root for common stuff as well -->
+	<Import Project="..\..\..\Common.Dotnet.CsWinRT.props" />
+	<Import Project="..\..\..\Common.Dotnet.FuzzTest.props" />
 	<PropertyGroup>
-		<TargetFramework>net8.0-windows10.0.19041.0</TargetFramework>
 		<LangVersion>latest</LangVersion>
 		<ImplicitUsings>enable</ImplicitUsings>
 		<Nullable>enable</Nullable>

src/modules/Hosts/Hosts.FuzzTests/Hosts.FuzzTests.csproj

@@ -1,6 +1,9 @@
 <Project Sdk="Microsoft.NET.Sdk">
+	<!-- Look at Directory.Build.props in root for common stuff as well -->
+	<Import Project="..\..\..\Common.Dotnet.CsWinRT.props" />
+	<Import Project="..\..\..\Common.Dotnet.FuzzTest.props" />
+
 	<PropertyGroup>
-		<TargetFramework>net8.0-windows10.0.19041.0</TargetFramework>
 		<LangVersion>latest</LangVersion>
 		<ImplicitUsings>enable</ImplicitUsings>
 	</PropertyGroup>

src/modules/cmdpal/ExtensionTemplate/TemplateCmdPalExtension/TemplateCmdPalExtension/Program.cs

@@ -14,11 +14,12 @@ namespace TemplateCmdPalExtension;
 public class Program
 {
     [MTAThread]
-    public static async Task Main(string[] args)
+    public static void Main(string[] args)
     {
         if (args.Length > 0 && args[0] == "-RegisterProcessAsComServer")
         {
-            await using global::Shmuelie.WinRTServer.ComServer server = new();
+            global::Shmuelie.WinRTServer.ComServer server = new();
+
             ManualResetEvent extensionDisposedEvent = new(false);
             
             // We are instantiating an extension instance once above, and returning it every time the callback in RegisterExtension below is called.
@@ -31,6 +32,8 @@ public class Program
             // This will make the main thread wait until the event is signalled by the extension class.
             // Since we have single instance of the extension object, we exit as soon as it is disposed.
             extensionDisposedEvent.WaitOne();
+            server.Stop();
+            server.UnsafeDispose();
         }
         else
         {

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/CommandItemViewModel.cs

@@ -190,7 +190,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
             contextItem.SlowInitializeProperties();
         });
 
-        if (!string.IsNullOrEmpty(model.Command.Name))
+        if (!string.IsNullOrEmpty(model.Command?.Name))
         {
             _defaultCommandContextItem = new(new CommandContextItem(model.Command!), PageContext)
             {

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/ListViewModel.cs

@@ -328,7 +328,19 @@ public partial class ListViewModel : PageViewModel, IDisposable
     }
 
     [RelayCommand]
-    private void UpdateSelectedItem(ListItemViewModel item)
+    private void UpdateSelectedItem(ListItemViewModel? item)
+    {
+        if (item != null)
+        {
+            SetSelectedItem(item);
+        }
+        else
+        {
+            ClearSelectedItem();
+        }
+    }
+
+    private void SetSelectedItem(ListItemViewModel item)
     {
         if (!item.SafeSlowInit())
         {
@@ -357,6 +369,23 @@ public partial class ListViewModel : PageViewModel, IDisposable
            });
     }
 
+    private void ClearSelectedItem()
+    {
+        // GH #322:
+        // For inexplicable reasons, if you try updating the command bar and
+        // the details on the same UI thread tick as updating the list, we'll
+        // explode
+        DoOnUiThread(
+           () =>
+           {
+               WeakReferenceMessenger.Default.Send<UpdateCommandBarMessage>(new(null));
+
+               WeakReferenceMessenger.Default.Send<HideDetailsMessage>();
+
+               TextToSuggest = string.Empty;
+           });
+    }
+
     public override void InitializeProperties()
     {
         base.InitializeProperties();

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/TopLevelCommandManager.cs

@@ -4,6 +4,7 @@
 
 using System.Collections.Immutable;
 using System.Collections.ObjectModel;
+using System.Diagnostics;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using CommunityToolkit.Mvvm.Messaging;
@@ -53,53 +54,44 @@ public partial class TopLevelCommandManager : ObservableObject,
         {
             CommandProviderWrapper wrapper = new(provider, _taskScheduler);
             _builtInCommands.Add(wrapper);
-            await LoadTopLevelCommandsFromProvider(wrapper);
+            var commands = await LoadTopLevelCommandsFromProvider(wrapper);
+            lock (TopLevelCommands)
+            {
+                foreach (var c in commands)
+                {
+                    TopLevelCommands.Add(c);
+                }
+            }
         }
 
         return true;
     }
 
     // May be called from a background thread
-    private async Task LoadTopLevelCommandsFromProvider(CommandProviderWrapper commandProvider)
+    private async Task<IEnumerable<TopLevelViewModel>> LoadTopLevelCommandsFromProvider(CommandProviderWrapper commandProvider)
     {
         WeakReference<IPageContext> weakSelf = new(this);
 
         await commandProvider.LoadTopLevelCommands(_serviceProvider, weakSelf);
 
         var settings = _serviceProvider.GetService<SettingsModel>()!;
-        var makeAndAdd = (ICommandItem? i, bool fallback) =>
+
+        List<TopLevelViewModel> commands = [];
+
+        foreach (var item in commandProvider.TopLevelItems)
         {
-            var commandItemViewModel = new CommandItemViewModel(new(i), weakSelf);
-            var topLevelViewModel = new TopLevelViewModel(commandItemViewModel, fallback, commandProvider.ExtensionHost, commandProvider.ProviderId, settings, _serviceProvider);
+            commands.Add(item);
+        }
 
-            lock (TopLevelCommands)
-            {
-                TopLevelCommands.Add(topLevelViewModel);
-            }
-        };
-
-        await Task.Factory.StartNew(
-            () =>
-            {
-                lock (TopLevelCommands)
-                {
-                    foreach (var item in commandProvider.TopLevelItems)
-                    {
-                        TopLevelCommands.Add(item);
-                    }
-
-                    foreach (var item in commandProvider.FallbackItems)
-                    {
-                        TopLevelCommands.Add(item);
-                    }
-                }
-            },
-            CancellationToken.None,
-            TaskCreationOptions.None,
-            _taskScheduler);
+        foreach (var item in commandProvider.FallbackItems)
+        {
+            commands.Add(item);
+        }
 
         commandProvider.CommandsChanged -= CommandProvider_CommandsChanged;
         commandProvider.CommandsChanged += CommandProvider_CommandsChanged;
+
+        return commands;
     }
 
     // By all accounts, we're already on a background thread (the COM call
@@ -239,25 +231,71 @@ public partial class TopLevelCommandManager : ObservableObject,
 
     private async Task StartExtensionsAndGetCommands(IEnumerable<IExtensionWrapper> extensions)
     {
-        // TODO This most definitely needs a lock
-        foreach (var extension in extensions)
-        {
-            Logger.LogDebug($"Starting {extension.PackageFullName}");
-            try
-            {
-                // start it ...
-                await extension.StartExtensionAsync();
+        var timer = new Stopwatch();
+        timer.Start();
 
-                // ... and fetch the command provider from it.
-                CommandProviderWrapper wrapper = new(extension, _taskScheduler);
-                _extensionCommandProviders.Add(wrapper);
-                await LoadTopLevelCommandsFromProvider(wrapper);
-            }
-            catch (Exception ex)
+        // Start all extensions in parallel
+        var startTasks = extensions.Select(StartExtensionWithTimeoutAsync);
+
+        // Wait for all extensions to start
+        var wrappers = (await Task.WhenAll(startTasks)).Where(wrapper => wrapper != null).Select(w => w!).ToList();
+
+        foreach (var wrapper in wrappers)
+        {
+            _extensionCommandProviders.Add(wrapper!);
+        }
+
+        // Load the commands from the providers in parallel
+        var loadTasks = wrappers.Select(LoadCommandsWithTimeoutAsync);
+
+        var commandSets = (await Task.WhenAll(loadTasks)).Where(results => results != null).Select(r => r!).ToList();
+
+        lock (TopLevelCommands)
+        {
+            foreach (var commands in commandSets)
             {
-                Logger.LogError(ex.ToString());
+                foreach (var c in commands)
+                {
+                    TopLevelCommands.Add(c);
+                }
             }
         }
+
+        timer.Stop();
+        Logger.LogDebug($"Loading extensions took {timer.ElapsedMilliseconds} ms");
+    }
+
+    private async Task<CommandProviderWrapper?> StartExtensionWithTimeoutAsync(IExtensionWrapper extension)
+    {
+        Logger.LogDebug($"Starting {extension.PackageFullName}");
+        try
+        {
+            await extension.StartExtensionAsync().WaitAsync(TimeSpan.FromSeconds(10));
+            return new CommandProviderWrapper(extension, _taskScheduler);
+        }
+        catch (Exception ex)
+        {
+            Logger.LogError($"Failed to start extension {extension.PackageFullName}: {ex}");
+            return null; // Return null for failed extensions
+        }
+    }
+
+    private async Task<IEnumerable<TopLevelViewModel>?> LoadCommandsWithTimeoutAsync(CommandProviderWrapper wrapper)
+    {
+        try
+        {
+            return await LoadTopLevelCommandsFromProvider(wrapper!).WaitAsync(TimeSpan.FromSeconds(10));
+        }
+        catch (TimeoutException)
+        {
+            Logger.LogError($"Loading commands from {wrapper!.ExtensionHost?.Extension?.PackageFullName} timed out");
+        }
+        catch (Exception ex)
+        {
+            Logger.LogError($"Failed to load commands for extension {wrapper!.ExtensionHost?.Extension?.PackageFullName}: {ex}");
+        }
+
+        return null;
     }
 
     private void ExtensionService_OnExtensionRemoved(IExtensionService sender, IEnumerable<IExtensionWrapper> extensions)

src/modules/cmdpal/Microsoft.CmdPal.UI/ExtViews/ListPage.xaml.cs

@@ -124,14 +124,12 @@ public sealed partial class ListPage : Page,
     [System.Diagnostics.CodeAnalysis.SuppressMessage("CodeQuality", "IDE0051:Remove unused private members", Justification = "VS is too aggressive at pruning methods bound in XAML")]
     private void ItemsList_SelectionChanged(object sender, SelectionChangedEventArgs e)
     {
-        if (ItemsList.SelectedItem is ListItemViewModel item)
+        var vm = ViewModel;
+        var li = ItemsList.SelectedItem as ListItemViewModel;
+        _ = Task.Run(() =>
         {
-            var vm = ViewModel;
-            _ = Task.Run(() =>
-            {
-                vm?.UpdateSelectedItemCommand.Execute(item);
-            });
-        }
+            vm?.UpdateSelectedItemCommand.Execute(li);
+        });
 
         // There's mysterious behavior here, where the selection seemingly
         // changes to _nothing_ when we're backspacing to a single character.

src/modules/cmdpal/Microsoft.CmdPal.UI/MainWindow.xaml

@@ -1,4 +1,4 @@
-<Window
+<winuiex:WindowEx
     x:Class="Microsoft.CmdPal.UI.MainWindow"
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
@@ -6,8 +6,13 @@
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
     xmlns:pages="using:Microsoft.CmdPal.UI.Pages"
     xmlns:viewmodels="using:Microsoft.CmdPal.UI.ViewModels"
+    xmlns:winuiex="using:WinUIEx"
+    Width="800"
+    Height="480"
+    MinWidth="320"
+    MinHeight="240"
     Activated="MainWindow_Activated"
     Closed="MainWindow_Closed"
     mc:Ignorable="d">
     <pages:ShellPage x:Name="RootShellPage" />
-</Window>
+</winuiex:WindowEx>

src/modules/cmdpal/Microsoft.CmdPal.UI/MainWindow.xaml.cs

@@ -25,15 +25,17 @@ using Windows.UI;
 using Windows.UI.WindowManagement;
 using Windows.Win32;
 using Windows.Win32.Foundation;
+using Windows.Win32.Graphics.Dwm;
 using Windows.Win32.UI.Input.KeyboardAndMouse;
 using Windows.Win32.UI.Shell;
 using Windows.Win32.UI.WindowsAndMessaging;
 using WinRT;
+using WinUIEx;
 using RS_ = Microsoft.CmdPal.UI.Helpers.ResourceLoaderInstance;
 
 namespace Microsoft.CmdPal.UI;
 
-public sealed partial class MainWindow : Window,
+public sealed partial class MainWindow : WindowEx,
     IRecipient<DismissMessage>,
     IRecipient<ShowWindowMessage>,
     IRecipient<HideWindowMessage>,
@@ -82,7 +84,6 @@ public sealed partial class MainWindow : Window,
 
         this.SetIcon();
         AppWindow.Title = RS_.GetString("AppName");
-        AppWindow.Resize(new SizeInt32 { Width = 1000, Height = 620 });
         PositionCentered();
         SetAcrylic();
 
@@ -232,6 +233,16 @@ public sealed partial class MainWindow : Window,
         PositionCentered(display);
 
         PInvoke.ShowWindow(hwnd, SHOW_WINDOW_CMD.SW_SHOW);
+
+        // instead of showing the window, uncloak it from DWM
+        // This will make it visible to the user, without the animation or frames for
+        // loading XAML with composition
+        unsafe
+        {
+            BOOL value = false;
+            PInvoke.DwmSetWindowAttribute(_hwnd, DWMWINDOWATTRIBUTE.DWMWA_CLOAK, (void*)&value, (uint)sizeof(BOOL));
+        }
+
         PInvoke.SetForegroundWindow(hwnd);
         PInvoke.SetActiveWindow(hwnd);
     }
@@ -289,7 +300,7 @@ public sealed partial class MainWindow : Window,
         ShowHwnd(message.Hwnd, settings.SummonOn);
     }
 
-    public void Receive(HideWindowMessage message) => PInvoke.ShowWindow(_hwnd, SHOW_WINDOW_CMD.SW_HIDE);
+    public void Receive(HideWindowMessage message) => HideWindow();
 
     public void Receive(QuitMessage message) =>
 
@@ -297,7 +308,21 @@ public sealed partial class MainWindow : Window,
         DispatcherQueue.TryEnqueue(() => Close());
 
     public void Receive(DismissMessage message) =>
-        PInvoke.ShowWindow(_hwnd, SHOW_WINDOW_CMD.SW_HIDE);
+        HideWindow();
+
+    private void HideWindow()
+    {
+        // Hide our window
+
+        // Instead of hiding the window, cloak it from DWM
+        // This will make it invisible to the user, such that we can show it again
+        // by uncloaking it, which avoids an unnecessary "flicker in" that XAML does
+        unsafe
+        {
+            BOOL value = true;
+            PInvoke.DwmSetWindowAttribute(_hwnd, DWMWINDOWATTRIBUTE.DWMWA_CLOAK, (void*)&value, (uint)sizeof(BOOL));
+        }
+    }
 
     internal void MainWindow_Closed(object sender, WindowEventArgs args)
     {
@@ -386,7 +411,9 @@ public sealed partial class MainWindow : Window,
                 return;
             }
 
-            PInvoke.ShowWindow(_hwnd, SHOW_WINDOW_CMD.SW_HIDE);
+            // This will DWM cloak our window:
+            HideWindow();
+
             PowerToysTelemetry.Log.WriteEvent(new CmdPalDismissedOnLostFocus());
         }
 
@@ -404,11 +431,6 @@ public sealed partial class MainWindow : Window,
         // know till the message is being handled.
         WeakReferenceMessenger.Default.Send<HotkeySummonMessage>(new(commandId, _hwnd));
 
-#pragma warning disable SA1310 // Field names should not contain underscore
-    private const uint DOT_KEY = 0xBE;
-    private const uint WM_HOTKEY = 0x0312;
-#pragma warning restore SA1310 // Field names should not contain underscore
-
     private void UnregisterHotkeys()
     {
         _keyboardListener.ClearHotkeys();
@@ -479,10 +501,24 @@ public sealed partial class MainWindow : Window,
         var isRootHotkey = string.IsNullOrEmpty(commandId);
         PowerToysTelemetry.Log.WriteEvent(new CmdPalHotkeySummoned(isRootHotkey));
 
+        var isVisible = this.Visible;
+        unsafe
+        {
+            // We need to check if our window is cloaked or not. A cloaked window is still
+            // technically visible, because SHOW/HIDE != iconic (minimized) != cloaked
+            // (these are all separate states)
+            long attr = 0;
+            PInvoke.DwmGetWindowAttribute(_hwnd, DWMWINDOWATTRIBUTE.DWMWA_CLOAKED, &attr, sizeof(long));
+            if (attr == 1 /* DWM_CLOAKED_APP */)
+            {
+                isVisible = false;
+            }
+        }
+
         // Note to future us: the wParam will have the index of the hotkey we registered.
         // We can use that in the future to differentiate the hotkeys we've pressed
         // so that we can bind hotkeys to individual commands
-        if (!this.Visible || !isRootHotkey)
+        if (!isVisible || !isRootHotkey)
         {
             Activate();
 
@@ -490,7 +526,16 @@ public sealed partial class MainWindow : Window,
         }
         else if (isRootHotkey)
         {
-            PInvoke.ShowWindow(_hwnd, SHOW_WINDOW_CMD.SW_HIDE);
+            // If there's a debugger attached...
+            if (System.Diagnostics.Debugger.IsAttached)
+            {
+                // ... then manually hide our window. When debugged, we won't get the cool cloaking,
+                // but that's the price to pay for having the HWND not light-dismiss while we're debugging.
+                PInvoke.ShowWindow(_hwnd, SHOW_WINDOW_CMD.SW_HIDE);
+                return;
+            }
+
+            HideWindow();
         }
     }
 
@@ -502,7 +547,10 @@ public sealed partial class MainWindow : Window,
     {
         switch (uMsg)
         {
-            case WM_HOTKEY:
+            // Prevent the window from maximizing when double-clicking the title bar area
+            case PInvoke.WM_NCLBUTTONDBLCLK:
+                return (LRESULT)IntPtr.Zero;
+            case PInvoke.WM_HOTKEY:
                 {
                     var hotkeyIndex = (int)wParam.Value;
                     if (hotkeyIndex < _hotkeys.Count)
@@ -518,22 +566,6 @@ public sealed partial class MainWindow : Window,
 
                         var hotkey = _hotkeys[hotkeyIndex];
                         HandleSummon(hotkey.CommandId);
-
-                        // var isRootHotkey = string.IsNullOrEmpty(hotkey.CommandId);
-
-                        // // Note to future us: the wParam will have the index of the hotkey we registered.
-                        // // We can use that in the future to differentiate the hotkeys we've pressed
-                        // // so that we can bind hotkeys to individual commands
-                        // if (!this.Visible || !isRootHotkey)
-                        // {
-                        //     Activate();
-
-                        // Summon(hotkey.CommandId);
-                        // }
-                        // else if (isRootHotkey)
-                        // {
-                        //     PInvoke.ShowWindow(hwnd, SHOW_WINDOW_CMD.SW_HIDE);
-                        // }
                     }
 
                     return (LRESULT)IntPtr.Zero;

src/modules/cmdpal/Microsoft.CmdPal.UI/Microsoft.CmdPal.UI.csproj

@@ -66,7 +66,7 @@
     <PackageReference Include="Microsoft.Windows.SDK.BuildTools" />
     <PackageReference Include="Microsoft.WindowsAppSDK" />
     <PackageReference Include="Microsoft.Xaml.Behaviors.WinUI.Managed" />
-
+	<PackageReference Include="WinUIEx" />
     <PackageReference Include="Microsoft.Windows.CsWin32">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>

src/modules/cmdpal/Microsoft.CmdPal.UI/NativeMethods.txt

@@ -25,6 +25,8 @@ SHCreateStreamOnFileEx
 CoAllowSetForegroundWindow
 SHCreateStreamOnFileEx
 SHLoadIndirectString
+WM_HOTKEY
+WM_NCLBUTTONDBLCLK
 
 Shell_NotifyIcon
 LoadIcon
@@ -36,3 +38,7 @@ ExtractIconEx
 WM_RBUTTONUP
 WM_LBUTTONUP
 WM_LBUTTONDBLCLK
+
+DwmGetWindowAttribute
+DwmSetWindowAttribute
+DWM_CLOAKED_APP

src/modules/cmdpal/Microsoft.CmdPal.UI/Pages/ShellPage.xaml.cs

@@ -418,9 +418,6 @@ public sealed partial class ShellPage : Microsoft.UI.Xaml.Controls.Page,
     {
         _ = DispatcherQueue.TryEnqueue(() =>
         {
-            // Also hide our details pane about here, if we had one
-            HideDetails();
-
             if (_settingsWindow == null)
             {
                 _settingsWindow = new SettingsWindow();

src/modules/cmdpal/Microsoft.CmdPal.UI/Settings/SettingsWindow.xaml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8" ?>
-<Window
+<winuiex:WindowEx
     x:Class="Microsoft.CmdPal.UI.Settings.SettingsWindow"
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
@@ -7,13 +7,18 @@
     xmlns:local="using:Microsoft.CmdPal.UI.Settings"
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
     xmlns:ui="using:CommunityToolkit.WinUI"
+    xmlns:winuiex="using:WinUIEx"
     Title="SettingsWindow"
+    Width="1280"
+    Height="720"
+    MinWidth="480"
+    MinHeight="480"
     Activated="Window_Activated"
     Closed="Window_Closed"
     mc:Ignorable="d">
-    <Window.SystemBackdrop>
+    <winuiex:WindowEx.SystemBackdrop>
         <MicaBackdrop />
-    </Window.SystemBackdrop>
+    </winuiex:WindowEx.SystemBackdrop>
     <Grid>
         <Grid.RowDefinitions>
             <RowDefinition Height="Auto" />
@@ -37,10 +42,10 @@
                 Height="16"
                 Source="ms-appx:///Assets/icon.svg" />
             <TextBlock
+                x:Uid="CmdPalSettingsHeader"
                 Margin="12,0,0,0"
                 VerticalAlignment="Center"
-                Style="{StaticResource CaptionTextBlockStyle}"
-                Text="Command Palette Settings" />
+                Style="{StaticResource CaptionTextBlockStyle}" />
         </StackPanel>
         <NavigationView
             x:Name="NavView"
@@ -100,4 +105,4 @@
             </Grid>
         </NavigationView>
     </Grid>
-</Window>
+</winuiex:WindowEx>

src/modules/cmdpal/Microsoft.CmdPal.UI/Settings/SettingsWindow.xaml.cs

@@ -11,11 +11,12 @@ using Microsoft.UI.Windowing;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
 using Windows.Graphics;
+using WinUIEx;
 using RS_ = Microsoft.CmdPal.UI.Helpers.ResourceLoaderInstance;
 
 namespace Microsoft.CmdPal.UI.Settings;
 
-public sealed partial class SettingsWindow : Window,
+public sealed partial class SettingsWindow : WindowEx,
     IRecipient<NavigateToExtensionSettingsMessage>,
     IRecipient<QuitMessage>
 {
@@ -70,7 +71,6 @@ public sealed partial class SettingsWindow : Window,
 
     private void PositionCentered()
     {
-        AppWindow.Resize(new SizeInt32 { Width = 1280, Height = 720 });
         var displayArea = DisplayArea.GetFromWindowId(AppWindow.Id, DisplayAreaFallback.Nearest);
         if (displayArea is not null)
         {

src/modules/cmdpal/Microsoft.CmdPal.UI/ToastWindow.xaml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8" ?>
-<Window
+<winuiex:WindowEx
     x:Class="Microsoft.CmdPal.UI.ToastWindow"
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
@@ -7,17 +7,18 @@
     xmlns:local="using:Microsoft.CmdPal.UI"
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
     xmlns:ui="using:CommunityToolkit.WinUI"
+    xmlns:winuiex="using:WinUIEx"
     Title="Command Palette Toast"
     mc:Ignorable="d">
-    <Window.SystemBackdrop>
+    <winuiex:WindowEx.SystemBackdrop>
         <DesktopAcrylicBackdrop />
-    </Window.SystemBackdrop>
+    </winuiex:WindowEx.SystemBackdrop>
     <Grid x:Name="ToastGrid">
         <!--  This padding is used to calculate the dimensions of the ToastWindow  -->
         <TextBlock
             x:Name="ToastText"
-            Padding="16,16,36,24"
+            Padding="12,12,24,20"
             Text="{x:Bind ViewModel.ToastMessage, Mode=OneWay}"
             TextAlignment="Center" />
     </Grid>
-</Window>
+</winuiex:WindowEx>

src/modules/cmdpal/Microsoft.CmdPal.UI/ToastWindow.xaml.cs

@@ -17,11 +17,12 @@ using Windows.Win32.Foundation;
 using Windows.Win32.Graphics.Gdi;
 using Windows.Win32.UI.HiDpi;
 using Windows.Win32.UI.WindowsAndMessaging;
+using WinUIEx;
 using RS_ = Microsoft.CmdPal.UI.Helpers.ResourceLoaderInstance;
 
 namespace Microsoft.CmdPal.UI;
 
-public sealed partial class ToastWindow : Window,
+public sealed partial class ToastWindow : WindowEx,
     IRecipient<QuitMessage>
 {
     private readonly HWND _hwnd;
@@ -64,19 +65,7 @@ public sealed partial class ToastWindow : Window,
 
     private void PositionCentered()
     {
-        var intSize = new SizeInt32
-        {
-            Width = Convert.ToInt32(ToastText.ActualWidth),
-            Height = Convert.ToInt32(ToastText.ActualHeight),
-        };
-
-        var scaleAdjustment = GetScaleFactor(_hwnd);
-        var scaled = new SizeInt32
-        {
-            Width = (int)Math.Round(intSize.Width * scaleAdjustment),
-            Height = (int)Math.Round(intSize.Height * scaleAdjustment),
-        };
-        AppWindow.Resize(scaled);
+        this.SetWindowSize(ToastText.ActualWidth, ToastText.ActualHeight);
 
         var displayArea = DisplayArea.GetFromWindowId(AppWindow.Id, DisplayAreaFallback.Nearest);
         if (displayArea is not null)
@@ -86,7 +75,7 @@ public sealed partial class ToastWindow : Window,
 
             var monitorHeight = displayArea.WorkArea.Height;
             var windowHeight = AppWindow.Size.Height;
-            centeredPosition.Y = monitorHeight - (windowHeight * 2);
+            centeredPosition.Y = monitorHeight - (windowHeight + 8); // Align with other shell toasts, like the volume indicator.
             AppWindow.Move(centeredPosition);
         }
     }

src/modules/cmdpal/README.md

@@ -9,7 +9,7 @@ By default, CmdPal is bound to <kbd>Win+Alt+Space</kbd>.
 
 The fastest way to get started is just to run the "Create extension" command in the palette itself. That'll prompt you for a project name and a Display Name, and where you want to place your project. Then just open the `sln` it produces. You should be ready to go 🙂. 
 
-The official API documentation can be found [on this docs site](TODO! Add docs link when we have one)
+The official API documentation can be found [on this docs site](https://learn.microsoft.com/windows/powertoys/command-palette/extensibility-overview).
 
 We've also got samples, so that you can see how the APIs in-action. 
 

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/AppCache.cs

@@ -12,7 +12,7 @@ using Microsoft.CmdPal.Ext.Apps.Utils;
 
 namespace Microsoft.CmdPal.Ext.Apps;
 
-public sealed class AppCache : IDisposable
+public sealed partial class AppCache : IDisposable
 {
     private Win32ProgramFileSystemWatchers _win32ProgramRepositoryHelper;
 

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Microsoft.CmdPal.Ext.Apps.csproj

@@ -1,11 +1,13 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <Import Project="..\..\..\..\Common.Dotnet.CsWinRT.props" />
+	<Import Project="..\..\..\..\Common.Dotnet.AotCompatibility.props" />
   <PropertyGroup>
     <RootNamespace>Microsoft.CmdPal.Ext.Apps</RootNamespace>
     <Nullable>enable</Nullable>
     <OutputPath>$(SolutionDir)$(Platform)\$(Configuration)\WinUI3Apps\CmdPal</OutputPath>
     <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
     <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
+	<AllowUnsafeBlocks>true</AllowUnsafeBlocks>
   </PropertyGroup>
 
   <ItemGroup>

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/NativeMethods.txt

@@ -1,7 +1,6 @@
 GetPhysicallyInstalledSystemMemory
 GlobalMemoryStatusEx
 GetSystemInfo
-CoCreateInstance
 SetForegroundWindow
 IsIconic
 RegisterHotKey
@@ -13,7 +12,6 @@ SetFocus
 SetActiveWindow
 MonitorFromWindow
 GetMonitorInfo
-SHCreateStreamOnFileEx
 CoAllowSetForegroundWindow
-SHCreateStreamOnFileEx
-SHLoadIndirectString
+SHLoadIndirectString
+IStream

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Programs/ReparsePoint.cs

@@ -319,7 +319,7 @@ public static class ReparsePoint
 
         public static AppExecutionAliasMetadata FromPersistedRepresentationIntPtr(IntPtr reparseDataBufferPtr, AppExecutionAliasReparseTagBufferLayoutVersion version)
         {
-            var dataOffset = Marshal.SizeOf(typeof(AppExecutionAliasReparseTagHeader));
+            var dataOffset = Marshal.SizeOf<AppExecutionAliasReparseTagHeader>();
             var dataBufferPtr = reparseDataBufferPtr + dataOffset;
 
             string? packageFullName = null;

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Programs/UWP.cs

@@ -6,6 +6,7 @@ using System;
 using System.Collections.Generic;
 using System.IO.Abstractions;
 using System.Linq;
+using System.Runtime.InteropServices;
 using System.Xml.Linq;
 using Microsoft.CmdPal.Ext.Apps.Utils;
 using Windows.Win32;
@@ -65,11 +66,18 @@ public partial class UWP
         const uint noAttribute = 0x80;
 
         var access = (uint)STGM.READ;
-        var hResult = PInvoke.SHCreateStreamOnFileEx(path, access, noAttribute, false, null, out IStream stream);
+        var hResult = Native.SHCreateStreamOnFileEx(path, access, noAttribute, false, IntPtr.Zero, out var streamPtr);
 
         // S_OK
         if (hResult == 0)
         {
+            // create IStream from streamPtr
+            var stream = Marshal.GetTypedObjectForIUnknown(streamPtr, typeof(IStream)) as IStream;
+            if (stream == null)
+            {
+                return;
+            }
+
             Apps = AppxPackageHelper.GetAppsFromManifest(stream).Select(appInManifest => new UWPApplication(appInManifest, this)).Where(a =>
             {
                 var valid =

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Programs/UWPApplication.cs

@@ -197,9 +197,10 @@ public class UWPApplication : IProgram
                 parsedFallback = prefix + "///" + key;
             }
 
-            var outBuffer = new StringBuilder(128);
+            var outBuffer = new char[1024];
+
             var source = $"@{{{packageFullName}? {parsed}}}";
-            var capacity = (uint)outBuffer.Capacity;
+            var capacity = (uint)outBuffer.Length;
             var hResult = SHLoadIndirectString(source, outBuffer, capacity, IntPtr.Zero);
             if (hResult != HRESULT.S_OK)
             {

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Storage/FileSystemWatcherWrapper.cs

@@ -8,7 +8,7 @@ using System.IO;
 namespace Microsoft.CmdPal.Ext.Apps.Storage;
 
 // File System Watcher Wrapper class which implements the IFileSystemWatcherWrapper interface
-public sealed class FileSystemWatcherWrapper : FileSystemWatcher, IFileSystemWatcherWrapper
+public sealed partial class FileSystemWatcherWrapper : FileSystemWatcher, IFileSystemWatcherWrapper
 {
     public FileSystemWatcherWrapper()
     {

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Storage/PackageRepository.cs

@@ -15,7 +15,7 @@ namespace Microsoft.CmdPal.Ext.Apps.Storage;
 /// A repository for storing packaged applications such as UWP apps or appx packaged desktop apps.
 /// This repository will also monitor for changes to the PackageCatalog and update the repository accordingly
 /// </summary>
-internal sealed class PackageRepository : ListRepository<UWPApplication>, IProgramRepository
+internal sealed partial class PackageRepository : ListRepository<UWPApplication>, IProgramRepository
 {
     private readonly IPackageCatalog _packageCatalog;
 

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Storage/Win32ProgramFileSystemWatchers.cs

@@ -9,7 +9,7 @@ using System.Linq;
 
 namespace Microsoft.CmdPal.Ext.Apps.Storage;
 
-internal sealed class Win32ProgramFileSystemWatchers : IDisposable
+internal sealed partial class Win32ProgramFileSystemWatchers : IDisposable
 {
     public string[] PathsToWatch { get; set; }
 

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Storage/Win32ProgramRepository.cs

@@ -14,7 +14,7 @@ using Win32Program = Microsoft.CmdPal.Ext.Apps.Programs.Win32Program;
 
 namespace Microsoft.CmdPal.Ext.Apps.Storage;
 
-internal sealed class Win32ProgramRepository : ListRepository<Programs.Win32Program>, IProgramRepository
+internal sealed partial class Win32ProgramRepository : ListRepository<Programs.Win32Program>, IProgramRepository
 {
     private static readonly IFileSystem FileSystem = new FileSystem();
     private static readonly IPath Path = FileSystem.Path;

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Utils/Native.cs

@@ -5,24 +5,28 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
 using System.Runtime.InteropServices;
-using System.Text;
+using System.Runtime.InteropServices.Marshalling;
+using Dia2Lib;
 
 namespace Microsoft.CmdPal.Ext.Apps.Utils;
 
 [SuppressMessage("Interoperability", "CA1401:P/Invokes should not be visible", Justification = "We want plugins to share this NativeMethods class, instead of each one creating its own.")]
-public sealed class Native
+public sealed partial class Native
 {
-    [DllImport("shlwapi.dll", CharSet = CharSet.Unicode)]
-    public static extern int SHLoadIndirectString(string pszSource, StringBuilder pszOutBuf, int cchOutBuf, nint ppvReserved);
+    [LibraryImport("shell32.dll", SetLastError = true, StringMarshalling = StringMarshalling.Utf16)]
+    public static partial int SHCreateItemFromParsingName([MarshalAs(UnmanagedType.LPWStr)] string path, nint pbc, ref Guid riid, [MarshalUsing(typeof(IShellItemMarshallerOut))] out IShellItem? shellItem);
 
-    [DllImport("shell32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
-    public static extern int SHCreateItemFromParsingName([MarshalAs(UnmanagedType.LPWStr)] string path, nint pbc, ref Guid riid, [MarshalAs(UnmanagedType.Interface)] out IShellItem shellItem);
+    [LibraryImport("shlwapi.dll", StringMarshalling = StringMarshalling.Utf16)]
+    public static partial HRESULT SHLoadIndirectString(string pszSource, Span<char> pszOutBuf, uint cchOutBuf, nint ppvReserved);
 
-    [DllImport("shlwapi.dll", CharSet = CharSet.Unicode)]
-    public static extern HRESULT SHCreateStreamOnFileEx(string fileName, STGM grfMode, uint attributes, bool create, System.Runtime.InteropServices.ComTypes.IStream reserved, out System.Runtime.InteropServices.ComTypes.IStream stream);
-
-    [DllImport("shlwapi.dll", CharSet = CharSet.Unicode)]
-    public static extern HRESULT SHLoadIndirectString(string pszSource, StringBuilder pszOutBuf, uint cchOutBuf, nint ppvReserved);
+    [LibraryImport("shlwapi.dll", StringMarshalling = StringMarshalling.Utf16)]
+    public static partial int SHCreateStreamOnFileEx(
+        string pszFile,
+        uint grfMode,
+        uint dwAttributes,
+        [MarshalAs(UnmanagedType.Bool)] bool fCreate,
+        IntPtr pstmTemplate,
+        out IntPtr ppstm);
 
     public enum HRESULT : uint
     {
@@ -129,14 +133,14 @@ public sealed class Native
     public interface IShellItem
     {
         void BindToHandler(
-            nint pbc,
-            [MarshalAs(UnmanagedType.LPStruct)] Guid bhid,
-            [MarshalAs(UnmanagedType.LPStruct)] Guid riid,
-            out nint ppv);
+            IntPtr pbc,
+            ref Guid bhid,
+            ref Guid riid,
+            out IntPtr ppv);
 
         void GetParent(out IShellItem ppsi);
 
-        void GetDisplayName(SIGDN sigdnName, [MarshalAs(UnmanagedType.LPWStr)] out string ppszName);
+        void GetDisplayName(SIGDN sigdnName, out IntPtr ppszName);
 
         void GetAttributes(uint sfgaoMask, out uint psfgaoAttribs);
 
@@ -154,4 +158,24 @@ public sealed class Native
         READWRITE = 0x00000002L,
         CREATE = 0x00001000L,
     }
+
+    [CustomMarshaller(typeof(IShellItem), MarshalMode.ManagedToUnmanagedOut, typeof(IShellItemMarshallerOut))]
+    public static partial class IShellItemMarshallerOut
+    {
+        public static IShellItem? ConvertToManaged(IntPtr unmanaged)
+        {
+            if (unmanaged == IntPtr.Zero)
+            {
+                return null;
+            }
+
+            var obj = Marshal.GetObjectForIUnknown(unmanaged);
+            return (IShellItem)obj;
+        }
+
+        public static void Free(IntPtr managed)
+        {
+            Marshal.FreeCoTaskMem(managed);
+        }
+    }
 }

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Utils/ShellLocalization.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Concurrent;
 using System.IO;
+using System.Runtime.InteropServices;
 using static Microsoft.CmdPal.Ext.Apps.Utils.Native;
 
 namespace Microsoft.CmdPal.Ext.Apps.Utils;
@@ -40,7 +41,20 @@ public class ShellLocalization
             return string.Empty;
         }
 
-        shellItem.GetDisplayName(SIGDN.NORMALDISPLAY, out var filename);
+        if (shellItem == null)
+        {
+            return string.Empty;
+        }
+
+        shellItem.GetDisplayName(SIGDN.NORMALDISPLAY, out var filenamePtr);
+
+        // get filename from ptr
+        var filename = Marshal.PtrToStringUni(filenamePtr);
+        Marshal.FreeCoTaskMem(filenamePtr);
+        if (filename == null)
+        {
+            return string.Empty;
+        }
 
         _ = _localizationCache.TryAdd(lowerInvariantPath, filename);
 

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/FallbackOpenFileItem.cs

@@ -2,7 +2,10 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
+using System.Globalization;
 using System.IO;
+using System.Text;
 using Microsoft.CmdPal.Ext.Indexer.Data;
 using Microsoft.CmdPal.Ext.Indexer.Properties;
 using Microsoft.CommandPalette.Extensions.Toolkit;
@@ -10,8 +13,14 @@ using Windows.Storage.Streams;
 
 namespace Microsoft.CmdPal.Ext.Indexer;
 
-internal sealed partial class FallbackOpenFileItem : FallbackCommandItem
+internal sealed partial class FallbackOpenFileItem : FallbackCommandItem, System.IDisposable
 {
+    private readonly CompositeFormat fallbackItemSearchPageTitleCompositeFormat = CompositeFormat.Parse(Resources.Indexer_fallback_searchPage_title);
+
+    private readonly SearchEngine _searchEngine = new();
+
+    private uint _queryCookie = 10;
+
     public FallbackOpenFileItem()
         : base(new NoOpCommand(), Resources.Indexer_Find_Path_fallback_display_title)
     {
@@ -21,8 +30,20 @@ internal sealed partial class FallbackOpenFileItem : FallbackCommandItem
 
     public override void UpdateQuery(string query)
     {
+        if (string.IsNullOrWhiteSpace(query))
+        {
+            Command = new NoOpCommand();
+            Title = string.Empty;
+            Subtitle = string.Empty;
+            Icon = null;
+            MoreCommands = null;
+
+            return;
+        }
+
         if (Path.Exists(query))
         {
+            // Exit 1: The query is a direct path to a file. Great! Return it.
             var item = new IndexerItem() { FullPath = query, FileName = Path.GetFileName(query) };
             var listItemForUs = new IndexerListItem(item, IncludeBrowseCommand.AsDefault);
             Command = listItemForUs.Command;
@@ -43,12 +64,65 @@ internal sealed partial class FallbackOpenFileItem : FallbackCommandItem
             catch
             {
             }
+
+            return;
         }
         else
         {
-            Title = string.Empty;
-            Subtitle = string.Empty;
-            Command = new NoOpCommand();
+            _queryCookie++;
+
+            try
+            {
+                _searchEngine.Query(query, _queryCookie);
+                var results = _searchEngine.FetchItems(0, 20, _queryCookie, out var _);
+
+                if (results.Count == 0 || ((results[0] as IndexerListItem) == null))
+                {
+                    // Exit 2: We searched for the file, and found nothing. Oh well.
+                    // Hide ourselves.
+                    Title = string.Empty;
+                    Subtitle = string.Empty;
+                    Command = new NoOpCommand();
+                    return;
+                }
+
+                if (results.Count == 1)
+                {
+                    // Exit 3: We searched for the file, and found exactly one thing. Awesome!
+                    // Return it.
+                    Title = results[0].Title;
+                    Subtitle = results[0].Subtitle;
+                    Icon = results[0].Icon;
+                    Command = results[0].Command;
+                    MoreCommands = results[0].MoreCommands;
+
+                    return;
+                }
+
+                // Exit 4: We found more than one result. Make our command take
+                // us to the file search page, prepopulated with this search.
+                var indexerPage = new IndexerPage(query, _searchEngine, _queryCookie, results);
+                Title = string.Format(CultureInfo.CurrentCulture, fallbackItemSearchPageTitleCompositeFormat, query);
+                Icon = Icons.FileExplorer;
+                Subtitle = Resources.Indexer_Subtitle;
+                Command = indexerPage;
+
+                return;
+            }
+            catch
+            {
+                Title = string.Empty;
+                Subtitle = string.Empty;
+                Icon = null;
+                Command = new NoOpCommand();
+                MoreCommands = null;
+            }
         }
     }
+
+    public void Dispose()
+    {
+        _searchEngine.Dispose();
+        GC.SuppressFinalize(this);
+    }
 }

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/Pages/IndexerPage.cs

@@ -4,25 +4,22 @@
 
 using System;
 using System.Collections.Generic;
-using System.Diagnostics;
 using System.Threading.Tasks;
-using ManagedCommon;
-using Microsoft.CmdPal.Ext.Indexer.Data;
-using Microsoft.CmdPal.Ext.Indexer.Indexer;
 using Microsoft.CmdPal.Ext.Indexer.Properties;
 using Microsoft.CommandPalette.Extensions;
 using Microsoft.CommandPalette.Extensions.Toolkit;
-using Windows.Storage.Streams;
 
 namespace Microsoft.CmdPal.Ext.Indexer;
 
 internal sealed partial class IndexerPage : DynamicListPage, IDisposable
 {
     private readonly List<IListItem> _indexerListItems = [];
+    private readonly SearchEngine _searchEngine;
+    private readonly bool disposeSearchEngine = true;
 
-    private SearchQuery _searchQuery = new();
+    private uint _queryCookie;
 
-    private uint _queryCookie = 10;
+    private string initialQuery = string.Empty;
 
     public IndexerPage()
     {
@@ -30,16 +27,31 @@ internal sealed partial class IndexerPage : DynamicListPage, IDisposable
         Icon = Icons.FileExplorer;
         Name = Resources.Indexer_Title;
         PlaceholderText = Resources.Indexer_PlaceholderText;
+        _searchEngine = new();
+        _queryCookie = 10;
+    }
+
+    public IndexerPage(string query, SearchEngine searchEngine, uint queryCookie, IList<IListItem> firstPageData)
+    {
+        Icon = Icons.FileExplorer;
+        Name = Resources.Indexer_Title;
+        _searchEngine = searchEngine;
+        _queryCookie = queryCookie;
+        _indexerListItems.AddRange(firstPageData);
+        initialQuery = query;
+        SearchText = query;
+        disposeSearchEngine = false;
     }
 
     public override void UpdateSearchText(string oldSearch, string newSearch)
     {
-        if (oldSearch != newSearch)
+        if (oldSearch != newSearch && newSearch != initialQuery)
         {
             _ = Task.Run(() =>
             {
                 Query(newSearch);
                 LoadMore();
+                initialQuery = string.Empty;
             });
         }
     }
@@ -49,7 +61,9 @@ internal sealed partial class IndexerPage : DynamicListPage, IDisposable
     public override void LoadMore()
     {
         IsLoading = true;
-        FetchItems(20);
+        var results = _searchEngine.FetchItems(_indexerListItems.Count, 20, _queryCookie, out var hasMore);
+        _indexerListItems.AddRange(results);
+        HasMoreItems = hasMore;
         IsLoading = false;
         RaiseItemsChanged(_indexerListItems.Count);
     }
@@ -58,70 +72,16 @@ internal sealed partial class IndexerPage : DynamicListPage, IDisposable
     {
         ++_queryCookie;
         _indexerListItems.Clear();
-        _searchQuery.SearchResults.Clear();
-        _searchQuery.CancelOutstandingQueries();
 
-        if (query == string.Empty)
-        {
-            return;
-        }
-
-        Stopwatch stopwatch = new();
-        stopwatch.Start();
-
-        _searchQuery.Execute(query, _queryCookie);
-
-        stopwatch.Stop();
-        Logger.LogDebug($"Query time: {stopwatch.ElapsedMilliseconds} ms, query: \"{query}\"");
-    }
-
-    private void FetchItems(int limit)
-    {
-        if (_searchQuery != null)
-        {
-            var cookie = _searchQuery.Cookie;
-            if (cookie == _queryCookie)
-            {
-                var index = 0;
-                SearchResult result;
-
-                var hasMoreItems = _searchQuery.FetchRows(_indexerListItems.Count, limit);
-
-                while (!_searchQuery.SearchResults.IsEmpty && _searchQuery.SearchResults.TryDequeue(out result) && ++index <= limit)
-                {
-                    IconInfo icon = null;
-                    try
-                    {
-                        var stream = ThumbnailHelper.GetThumbnail(result.LaunchUri).Result;
-                        if (stream != null)
-                        {
-                            var data = new IconData(RandomAccessStreamReference.CreateFromStream(stream));
-                            icon = new IconInfo(data, data);
-                        }
-                    }
-                    catch (Exception ex)
-                    {
-                        Logger.LogError("Failed to get the icon.", ex);
-                    }
-
-                    _indexerListItems.Add(new IndexerListItem(new IndexerItem
-                    {
-                        FileName = result.ItemDisplayName,
-                        FullPath = result.LaunchUri,
-                    })
-                    {
-                        Icon = icon,
-                    });
-                }
-
-                HasMoreItems = hasMoreItems;
-            }
-        }
+        _searchEngine.Query(query, _queryCookie);
     }
 
     public void Dispose()
     {
-        _searchQuery = null;
-        GC.SuppressFinalize(this);
+        if (disposeSearchEngine)
+        {
+            _searchEngine.Dispose();
+            GC.SuppressFinalize(this);
+        }
     }
 }

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

@@ -123,6 +123,15 @@ namespace Microsoft.CmdPal.Ext.Indexer.Properties {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Search for &quot;{0}&quot; in files.
+        /// </summary>
+        internal static string Indexer_fallback_searchPage_title {
+            get {
+                return ResourceManager.GetString("Indexer_fallback_searchPage_title", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to This file doesn&apos;t exist.
         /// </summary>
@@ -168,6 +177,42 @@ namespace Microsoft.CmdPal.Ext.Indexer.Properties {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Always on.
+        /// </summary>
+        internal static string Indexer_Settings_FallbackCommand_AlwaysOn {
+            get {
+                return ResourceManager.GetString("Indexer_Settings_FallbackCommand_AlwaysOn", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Only when file path exist.
+        /// </summary>
+        internal static string Indexer_Settings_FallbackCommand_FilePathExist {
+            get {
+                return ResourceManager.GetString("Indexer_Settings_FallbackCommand_FilePathExist", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Shows file search results on the top-level search results.
+        /// </summary>
+        internal static string Indexer_Settings_FallbackCommand_Mode {
+            get {
+                return ResourceManager.GetString("Indexer_Settings_FallbackCommand_Mode", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Always off.
+        /// </summary>
+        internal static string Indexer_Settings_FallbackCommand_Off {
+            get {
+                return ResourceManager.GetString("Indexer_Settings_FallbackCommand_Off", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Search files on this device.
         /// </summary>

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

@@ -156,10 +156,25 @@
   <data name="Indexer_PlaceholderText" xml:space="preserve">
     <value>Search for files and folders...</value>
   </data>
+  <data name="Indexer_Settings_FallbackCommand_AlwaysOn" xml:space="preserve">
+    <value>Always on</value>
+  </data>
+  <data name="Indexer_Settings_FallbackCommand_Mode" xml:space="preserve">
+    <value>Shows file search results on the top-level search results</value>
+  </data>
+  <data name="Indexer_Settings_FallbackCommand_Off" xml:space="preserve">
+    <value>Always off</value>
+  </data>
+  <data name="Indexer_Settings_FallbackCommand_FilePathExist" xml:space="preserve">
+    <value>Only when file path exist</value>
+  </data>
   <data name="Indexer_Subtitle" xml:space="preserve">
     <value>Search files on this device</value>
   </data>
   <data name="Indexer_Title" xml:space="preserve">
     <value>Search files</value>
   </data>
+  <data name="Indexer_fallback_searchPage_title" xml:space="preserve">
+    <value>Search for "{0}" in files</value>
+  </data>
 </root>

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/SearchEngine.cs

@@ -0,0 +1,95 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using ManagedCommon;
+using Microsoft.CmdPal.Ext.Indexer.Data;
+using Microsoft.CmdPal.Ext.Indexer.Indexer;
+using Microsoft.CommandPalette.Extensions;
+using Microsoft.CommandPalette.Extensions.Toolkit;
+using Windows.Storage.Streams;
+
+namespace Microsoft.CmdPal.Ext.Indexer;
+
+public sealed partial class SearchEngine : IDisposable
+{
+    private SearchQuery _searchQuery = new();
+
+    public void Query(string query, uint queryCookie)
+    {
+        // _indexerListItems.Clear();
+        _searchQuery.SearchResults.Clear();
+        _searchQuery.CancelOutstandingQueries();
+
+        if (query == string.Empty)
+        {
+            return;
+        }
+
+        Stopwatch stopwatch = new();
+        stopwatch.Start();
+
+        _searchQuery.Execute(query, queryCookie);
+
+        stopwatch.Stop();
+        Logger.LogDebug($"Query time: {stopwatch.ElapsedMilliseconds} ms, query: \"{query}\"");
+    }
+
+    public IList<IListItem> FetchItems(int offset, int limit, uint queryCookie, out bool hasMore)
+    {
+        hasMore = false;
+        var results = new List<IListItem>();
+        if (_searchQuery != null)
+        {
+            var cookie = _searchQuery.Cookie;
+            if (cookie == queryCookie)
+            {
+                var index = 0;
+                SearchResult result;
+
+                // var hasMoreItems = _searchQuery.FetchRows(_indexerListItems.Count, limit);
+                var hasMoreItems = _searchQuery.FetchRows(offset, limit);
+
+                while (!_searchQuery.SearchResults.IsEmpty && _searchQuery.SearchResults.TryDequeue(out result) && ++index <= limit)
+                {
+                    IconInfo icon = null;
+                    try
+                    {
+                        var stream = ThumbnailHelper.GetThumbnail(result.LaunchUri).Result;
+                        if (stream != null)
+                        {
+                            var data = new IconData(RandomAccessStreamReference.CreateFromStream(stream));
+                            icon = new IconInfo(data, data);
+                        }
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogError("Failed to get the icon.", ex);
+                    }
+
+                    results.Add(new IndexerListItem(new IndexerItem
+                    {
+                        FileName = result.ItemDisplayName,
+                        FullPath = result.LaunchUri,
+                    })
+                    {
+                        Icon = icon,
+                    });
+                }
+
+                hasMore = hasMoreItems;
+            }
+        }
+
+        return results;
+    }
+
+    public void Dispose()
+    {
+        _searchQuery = null;
+        GC.SuppressFinalize(this);
+    }
+}

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.System/FallbackSystemCommandItem.cs

@@ -32,6 +32,7 @@ internal sealed partial class FallbackSystemCommandItem : FallbackCommandItem
     {
         if (string.IsNullOrWhiteSpace(query))
         {
+            Command = null;
             Title = string.Empty;
             Subtitle = string.Empty;
             return;
@@ -58,6 +59,7 @@ internal sealed partial class FallbackSystemCommandItem : FallbackCommandItem
 
         if (result == null)
         {
+            Command = null;
             Title = string.Empty;
             Subtitle = string.Empty;
 

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.System/Pages/SystemCommandPage.cs

@@ -10,12 +10,12 @@ namespace Microsoft.CmdPal.Ext.System.Pages;
 
 public sealed partial class SystemCommandPage : ListPage
 {
-    private SettingsManager _settingsManager;
+    private readonly SettingsManager _settingsManager;
 
     public SystemCommandPage(SettingsManager settingsManager)
     {
-        Title = Resources.Microsoft_plugin_ext_system_page_name;
-        Name = Resources.Microsoft_plugin_ext_system_page_name;
+        Title = Resources.Microsoft_plugin_ext_system_page_title;
+        Name = Resources.Microsoft_plugin_command_name_open;
         Icon = IconHelpers.FromRelativePath("Assets\\SystemCommand.svg");
         _settingsManager = settingsManager;
         ShowDetails = true;

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

@@ -205,7 +205,7 @@ namespace Microsoft.CmdPal.Ext.System {
         }
         
         /// <summary>
-        ///   Looks up a localized string similar to Windows System Command.
+        ///   Looks up a localized string similar to System Commands.
         /// </summary>
         public static string Microsoft_plugin_ext_system_page_name {
             get {
@@ -213,6 +213,15 @@ namespace Microsoft.CmdPal.Ext.System {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Windows System Commands.
+        /// </summary>
+        public static string Microsoft_plugin_ext_system_page_title {
+            get {
+                return ResourceManager.GetString("Microsoft_plugin_ext_system_page_title", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Adapter name.
         /// </summary>

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

@@ -160,8 +160,11 @@
   <data name="Microsoft_plugin_ext_settings_hideDisconnectedNetworkInfo" xml:space="preserve">
     <value>Hide disconnected network info</value>
   </data>
+  <data name="Microsoft_plugin_ext_system_page_title" xml:space="preserve">
+    <value>Windows System Commands</value>
+  </data>
   <data name="Microsoft_plugin_ext_system_page_name" xml:space="preserve">
-    <value>Windows System Command</value>
+    <value>System Commands</value>
   </data>
   <data name="Microsoft_plugin_sys_AdapterName" xml:space="preserve">
     <value>Adapter name</value>

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.System/SystemCommandExtensionProvider.cs

@@ -14,7 +14,7 @@ public partial class SystemCommandExtensionProvider : CommandProvider
     private readonly ICommandItem[] _commands;
     private static readonly SettingsManager _settingsManager = new();
     public static readonly SystemCommandPage Page = new(_settingsManager);
-    private readonly FallbackSystemCommandItem _fallbackFileItem = new(_settingsManager);
+    private readonly FallbackSystemCommandItem _fallbackSystemItem = new(_settingsManager);
 
     public SystemCommandExtensionProvider()
     {
@@ -23,7 +23,7 @@ public partial class SystemCommandExtensionProvider : CommandProvider
         _commands = [
             new CommandItem(Page)
             {
-                Title = Resources.Microsoft_plugin_ext_system_page_name,
+                Title = Resources.Microsoft_plugin_ext_system_page_title,
                 Icon = Page.Icon,
                 MoreCommands = [new CommandContextItem(_settingsManager.Settings.SettingsPage)],
             },
@@ -38,5 +38,5 @@ public partial class SystemCommandExtensionProvider : CommandProvider
         return _commands;
     }
 
-    public override IFallbackCommandItem[] FallbackCommands() => [_fallbackFileItem];
+    public override IFallbackCommandItem[] FallbackCommands() => [_fallbackSystemItem];
 }

src/modules/registrypreview/RegistryPreview.FuzzTests/RegistryPreview.FuzzTests.csproj

@@ -1,9 +1,11 @@
 <Project Sdk="Microsoft.NET.Sdk">
+  <!-- Look at Directory.Build.props in root for common stuff as well -->
+  <Import Project="..\..\..\Common.Dotnet.CsWinRT.props" />
+  <Import Project="..\..\..\Common.Dotnet.FuzzTest.props" />
 
   <PropertyGroup>
-    <TargetFramework>net8.0-windows10.0.19041.0</TargetFramework>
-	<Platforms>x64;ARM64</Platforms>
-	<LangVersion>latest</LangVersion>
+    <Platforms>x64;ARM64</Platforms>
+    <LangVersion>latest</LangVersion>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
   </PropertyGroup>