Adding (temp) icon

Quality of life improvement for the dev loop: removing the dialog in
Settings, since we have a DEBUG header in the titlebar anyways.

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

@@ -115,6 +115,7 @@ bigbar
 bigobj
 binlog
 binres
+binskim
 BITMAPFILEHEADER
 bitmapimage
 BITMAPINFO
@@ -255,6 +256,7 @@ Corpor
 cotaskmem
 COULDNOT
 countof
+covrun
 cpcontrols
 cph
 cplusplus
@@ -635,6 +637,7 @@ hmodule
 hmonitor
 homies
 homljgmgpmcbpjbnjpfijnhipfkiclkd
+HOOKPROC
 HORZRES
 HORZSIZE
 Hostbackdropbrush
@@ -969,6 +972,7 @@ msc
 mscorlib
 msctls
 msdata
+msdia
 MSDL
 MSGFLT
 MSHCTX

.pipelines/v2/release.yml

@@ -64,6 +64,10 @@ extends:
       tsa:
         enabled: true
         configFile: '$(Build.SourcesDirectory)\.pipelines\tsa.json'
+      binskim:
+        enabled: true
+        # Exclude every dll/exe in tests/*, as well as all msdia*, covrun* and vcruntime*
+        analyzeTargetGlob: +:file|$(Build.ArtifactStagingDirectory)/**/*.dll;+:file|$(Build.ArtifactStagingDirectory)/**/*.exe;-:file:regex|tests.*\.(dll|exe)$;-:file:regex|(covrun.*)\.dll$;-:file:regex|(msdia.*)\.dll$;-:file:regex|(vcruntime.*)\.dll$
 
     stages:
       - stage: Build

PowerToys.sln

@@ -5,11 +5,13 @@ MinimumVisualStudioVersion = 10.0.40219.1
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "runner", "src\runner\runner.vcxproj", "{9412D5C6-2CF2-4FC2-A601-B55508EA9B27}"
 	ProjectSection(ProjectDependencies) = postProject
 		{031AC72E-FA28-4AB7-B690-6F7B9C28AA73} = {031AC72E-FA28-4AB7-B690-6F7B9C28AA73}
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC} = {08E71C67-6A7E-4CA1-B04E-2FB336410BAC}
 		{0B43679E-EDFA-4DA0-AD30-F4628B308B1B} = {0B43679E-EDFA-4DA0-AD30-F4628B308B1B}
 		{0B593A6C-4143-4337-860E-DB5710FB87DB} = {0B593A6C-4143-4337-860E-DB5710FB87DB}
 		{17DA04DF-E393-4397-9CF0-84DABE11032E} = {17DA04DF-E393-4397-9CF0-84DABE11032E}
 		{217DF501-135C-4E38-BFC8-99D4821032EA} = {217DF501-135C-4E38-BFC8-99D4821032EA}
 		{2BE46397-4DFA-414C-9BD4-41E4BBF8CB34} = {2BE46397-4DFA-414C-9BD4-41E4BBF8CB34}
+		{38177D56-6AD1-4ADF-88C9-2843A7932166} = {38177D56-6AD1-4ADF-88C9-2843A7932166}
 		{48804216-2A0E-4168-A6D8-9CD068D14227} = {48804216-2A0E-4168-A6D8-9CD068D14227}
 		{51920F1F-C28C-4ADF-8660-4238766796C2} = {51920F1F-C28C-4ADF-8660-4238766796C2}
 		{5CCC8468-DEC8-4D36-99D4-5C891BEBD481} = {5CCC8468-DEC8-4D36-99D4-5C891BEBD481}
@@ -788,6 +790,12 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Microsoft.CmdPal.Ext.Window
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Microsoft.CmdPal.Ext.UnitTestBase", "src\modules\cmdpal\Tests\Microsoft.CmdPal.Ext.UnitTestsBase\Microsoft.CmdPal.Ext.UnitTestBase.csproj", "{00D8659C-2068-40B6-8B86-759CD6284BBB}"
 EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "LightSwitch", "LightSwitch", "{5B201255-53C8-490B-A34F-01F05D48A477}"
+EndProject
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "LightSwitchModuleInterface", "src\modules\LightSwitch\LightSwitchModuleInterface\LightSwitchModuleInterface.vcxproj", "{38177D56-6AD1-4ADF-88C9-2843A7932166}"
+EndProject
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "LightModeService", "src\modules\LightSwitch\LightSwitchService\LightSwitchService.vcxproj", "{08E71C67-6A7E-4CA1-B04E-2FB336410BAC}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|ARM64 = Debug|ARM64
@@ -2850,6 +2858,22 @@ Global
 		{00D8659C-2068-40B6-8B86-759CD6284BBB}.Release|ARM64.Build.0 = Release|ARM64
 		{00D8659C-2068-40B6-8B86-759CD6284BBB}.Release|x64.ActiveCfg = Release|x64
 		{00D8659C-2068-40B6-8B86-759CD6284BBB}.Release|x64.Build.0 = Release|x64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Debug|ARM64.Build.0 = Debug|ARM64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Debug|x64.ActiveCfg = Debug|x64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Debug|x64.Build.0 = Debug|x64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Release|ARM64.ActiveCfg = Release|ARM64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Release|ARM64.Build.0 = Release|ARM64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Release|x64.ActiveCfg = Release|x64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Release|x64.Build.0 = Release|x64
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC}.Debug|ARM64.Build.0 = Debug|ARM64
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC}.Debug|x64.ActiveCfg = Debug|x64
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC}.Debug|x64.Build.0 = Debug|x64
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC}.Release|ARM64.ActiveCfg = Release|ARM64
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC}.Release|ARM64.Build.0 = Release|ARM64
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC}.Release|x64.ActiveCfg = Release|x64
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC}.Release|x64.Build.0 = Release|x64
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -3161,6 +3185,9 @@ Global
 		{E816D7AF-4688-4ECB-97CC-3D8E798F3828} = {8EF25507-2575-4ADE-BF7E-D23376903AB8}
 		{E816D7B0-4688-4ECB-97CC-3D8E798F3829} = {8EF25507-2575-4ADE-BF7E-D23376903AB8}
 		{00D8659C-2068-40B6-8B86-759CD6284BBB} = {8EF25507-2575-4ADE-BF7E-D23376903AB8}
+		{5B201255-53C8-490B-A34F-01F05D48A477} = {4574FDD0-F61D-4376-98BF-E5A1262C11EC}
+		{38177D56-6AD1-4ADF-88C9-2843A7932166} = {5B201255-53C8-490B-A34F-01F05D48A477}
+		{08E71C67-6A7E-4CA1-B04E-2FB336410BAC} = {5B201255-53C8-490B-A34F-01F05D48A477}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {C3A2F9D1-7930-4EF4-A6FC-7EE0A99821D0}

doc/devdocs/readme.md

@@ -52,7 +52,7 @@ Once you've discussed your proposed feature/fix/etc. with a team member, and an
 ## Rules
 
 - **Follow the pattern of what you already see in the code.**
-- [Coding style](development/style.md).
+- [Coding style](style.md).
 - Try to package new functionality/components into libraries that have nicely defined interfaces.
 - Package new functionality into classes or refactor existing functionality into a class as you extend the code.
 - When adding new classes/methods/changing existing code, add new unit tests or update the existing tests.

installer/PowerToysSetup/Product.wxs

@@ -206,11 +206,6 @@
       <!-- Clean Video Conference Mute registry keys that might be around from previous installations. We've deprecated this utility since then. -->
       <Custom Action="CleanVideoConferenceRegistry" Before="InstallFinalize">NOT Installed</Custom>
 
-      <!-- User may have disabled the built-in New context menu via New+ --> 
-      <Custom Action="RestoreBuiltInNewContextMenu" Before="RemoveFiles">
-         Installed AND (REMOVE="ALL")
-      </Custom>
-       
     </InstallExecuteSequence>
 
     <CustomAction Id="SetLaunchPowerToysParam"
@@ -467,14 +462,6 @@
                   DllEntry="InstallCmdPalPackageCA"
                   />
 
-    <CustomAction Id="RestoreBuiltInNewContextMenu"
-                  Return="ignore"
-                  Impersonate="yes"
-                  Execute="deferred"
-                  BinaryKey="PTCustomActions"
-                  DllEntry="RestoreBuiltInNewContextMenuCA"
-                  />     
-     
     <!-- Close 'PowerToys.exe' before uninstall-->
     <Property Id="MSIRESTARTMANAGERCONTROL" Value="DisableShutdown" />
     <Property Id="MSIFASTINSTALL" Value="DisableShutdown" />

installer/PowerToysSetup/Resources.wxs

@@ -11,7 +11,7 @@
   <Fragment>
     <!-- Resource directories should be added only if the installer is built on the build farm -->
     <?ifdef env.IsPipeline?>
-      <?foreach ParentDirectory in INSTALLFOLDER;HistoryPluginFolder;CalculatorPluginFolder;FolderPluginFolder;ProgramPluginFolder;ShellPluginFolder;IndexerPluginFolder;UnitConverterPluginFolder;ValueGeneratorPluginFolder;UriPluginFolder;WindowWalkerPluginFolder;OneNotePluginFolder;RegistryPluginFolder;VSCodeWorkspacesPluginFolder;ServicePluginFolder;SystemPluginFolder;TimeDatePluginFolder;WindowsSettingsPluginFolder;WindowsTerminalPluginFolder;WebSearchPluginFolder;PowerToysPluginFolder?>
+      <?foreach ParentDirectory in INSTALLFOLDER;WinUI3AppsInstallFolder;HistoryPluginFolder;CalculatorPluginFolder;FolderPluginFolder;ProgramPluginFolder;ShellPluginFolder;IndexerPluginFolder;UnitConverterPluginFolder;ValueGeneratorPluginFolder;UriPluginFolder;WindowWalkerPluginFolder;OneNotePluginFolder;RegistryPluginFolder;VSCodeWorkspacesPluginFolder;ServicePluginFolder;SystemPluginFolder;TimeDatePluginFolder;WindowsSettingsPluginFolder;WindowsTerminalPluginFolder;WebSearchPluginFolder;PowerToysPluginFolder?>
         <DirectoryRef Id="$(var.ParentDirectory)">
           <!-- Resource file directories -->
           <?foreach Language in $(var.LocLanguageList)?>
@@ -181,7 +181,7 @@
       </Component>
       <Component
           Id="ImageResizer_$(var.IdSafeLanguage)_Component"
-          Directory="Resource$(var.IdSafeLanguage)INSTALLFOLDER"
+          Directory="Resource$(var.IdSafeLanguage)WinUI3AppsInstallFolder"
           Guid="$(var.CompGUIDPrefix)02">
         <RegistryKey Root="$(var.RegistryScope)" Key="Software\Classes\powertoys\components">
           <RegistryValue Type="string" Name="ImageResizer_$(var.IdSafeLanguage)_Component" Value="" KeyPath="yes"/>
@@ -553,6 +553,7 @@
           <RemoveFolder Id="RemoveFolderResourcesResource$(var.IdSafeLanguage)HistoryPluginFolder" Directory="Resource$(var.IdSafeLanguage)HistoryPluginFolder" On="uninstall"/>
           <RemoveFolder Id="RemoveFolderResourcesResource$(var.IdSafeLanguage)PowerToysPluginFolder" Directory="Resource$(var.IdSafeLanguage)PowerToysPluginFolder" On="uninstall"/>
           <RemoveFolder Id="RemoveFolderResourcesResource$(var.IdSafeLanguage)ValueGeneratorPluginFolder" Directory="Resource$(var.IdSafeLanguage)ValueGeneratorPluginFolder" On="uninstall"/>
+          <RemoveFolder Id="RemoveFolderResourcesResource$(var.IdSafeLanguage)WinUI3AppsInstallFolder" Directory="Resource$(var.IdSafeLanguage)WinUI3AppsInstallFolder" On="uninstall"/>
       <?undef IdSafeLanguage?>
         <?endforeach?>
       </Component>

installer/PowerToysSetupCustomActions/CustomAction.cpp

@@ -1153,65 +1153,6 @@ UINT __stdcall UnRegisterContextMenuPackagesCA(MSIHANDLE hInstall)
     return WcaFinalize(er);
 }
 
-UINT __stdcall RestoreBuiltInNewContextMenuCA(MSIHANDLE hInstall)
-{
-    // Must be run as administrator to open and modify the registry.
-
-    HRESULT hr = S_OK;
-    UINT er = ERROR_SUCCESS;
-
-    hr = WcaInitialize(hInstall, "RestoreBuiltInNewContextMenuCA");
-
-    try
-    {
-        const std::wstring builtInNewRegistryPath = LR"(Directory\Background\shellex\ContextMenuHandlers\New)";
-        const std::wstring newDisabledValuePrefix = L"0_";
-
-        auto regDeleter = [](HKEY* regKeyHandle) { if (regKeyHandle && *regKeyHandle) RegCloseKey(*regKeyHandle); delete regKeyHandle; };
-        std::unique_ptr<HKEY, decltype(regDeleter)> regKeyHandle(new HKEY(nullptr), regDeleter);
-
-        const LONG openStatus = RegOpenKeyExW(HKEY_CLASSES_ROOT, builtInNewRegistryPath.c_str(), 0, KEY_READ | KEY_WRITE, regKeyHandle.get());
-        if (openStatus != ERROR_SUCCESS)
-        {
-            throw std::runtime_error("Failed to open New context menu registry key.");
-        }
-
-        wchar_t buffer[256];
-        DWORD bufferSize = sizeof(buffer);
-        const LONG queryStatus = RegQueryValueExW(*regKeyHandle, nullptr, nullptr, nullptr, reinterpret_cast<LPBYTE>(buffer), &bufferSize);
-        if (queryStatus != ERROR_SUCCESS)
-        {
-            throw std::runtime_error("Failed to read New context menu registry key.");
-        }
-
-        const std::wstring builtInNewHandlerValue(buffer);
-        const bool startsWithPrefix = builtInNewHandlerValue.find(newDisabledValuePrefix) == 0;
-
-        if (!startsWithPrefix)
-        {
-            return ERROR_SUCCESS;
-        }
-
-        const std::wstring builtInNewEnabledValue = builtInNewHandlerValue.substr(newDisabledValuePrefix.length());
-        const LONG setStatus = RegSetValueExW(*regKeyHandle, nullptr, 0, REG_SZ, reinterpret_cast<const BYTE*>(builtInNewEnabledValue.c_str()), static_cast<DWORD>((builtInNewEnabledValue.length() + 1)) * sizeof(wchar_t));
-        if (setStatus != ERROR_SUCCESS)
-        {
-            throw std::runtime_error("Failed to update/restore the New context menu shell extension in the registry.");
-        }
-    }
-    catch (const std::exception& e)
-    {
-        std::string errorMessage{ "Exception thrown while trying to restore built-in New: " };
-        errorMessage += e.what();
-        Logger::error(errorMessage);
-
-        er = ERROR_INSTALL_FAILURE;
-    }
-
-    er = er == ERROR_SUCCESS ? (SUCCEEDED(hr) ? ERROR_SUCCESS : ERROR_INSTALL_FAILURE) : er;
-    return WcaFinalize(er);
-}
-
 UINT __stdcall TerminateProcessesCA(MSIHANDLE hInstall)
 {
     HRESULT hr = S_OK;

installer/PowerToysSetupCustomActions/CustomAction.def

@@ -28,4 +28,3 @@ EXPORTS
 	UninstallCommandNotFoundModuleCA
 	UpgradeCommandNotFoundModuleCA
 	UnsetAdvancedPasteAPIKeyCA
-	RestoreBuiltInNewContextMenuCA

nuget.config

@@ -2,11 +2,11 @@
 <configuration>
 	<packageSources>
 		<clear />
-		<add key="PowerToysPublicDependencies" value="https://pkgs.dev.azure.com/shine-oss/PowerToys/_packaging/PowerToysPublicDependencies/nuget/v3/index.json" />
+		<add key="PowerToysPublicDependencies" value="https://pkgs.dev.azure.com/shine-oss/PowerToys/_packaging/PowerToysPublicDependencies%40Local/nuget/v3/index.json" />
 	</packageSources>
 	<packageSourceMapping>
 		<packageSource key="PowerToysPublicDependencies">
 			<package pattern="*" />
 		</packageSource>
 	</packageSourceMapping>
-</configuration>
+</configuration>

src/common/Common.UI/SettingsDeepLink.cs

@@ -17,6 +17,7 @@ namespace Common.UI
             Awake,
             ColorPicker,
             CmdNotFound,
+            LightSwitch,
             FancyZones,
             FileLocksmith,
             Run,
@@ -60,6 +61,8 @@ namespace Common.UI
                     return "ColorPicker";
                 case SettingsWindow.CmdNotFound:
                     return "CmdNotFound";
+                case SettingsWindow.LightSwitch:
+                    return "LightSwitch";
                 case SettingsWindow.FancyZones:
                     return "FancyZones";
                 case SettingsWindow.FileLocksmith:

src/common/GPOWrapper/GPOWrapper.cpp

@@ -28,6 +28,10 @@ namespace winrt::PowerToys::GPOWrapper::implementation
     {
         return static_cast<GpoRuleConfigured>(powertoys_gpo::getConfiguredCropAndLockEnabledValue());
     }
+    GpoRuleConfigured GPOWrapper::GetConfiguredLightSwitchEnabledValue()
+    {
+        return static_cast<GpoRuleConfigured>(powertoys_gpo::getConfiguredLightSwitchEnabledValue());
+    }
     GpoRuleConfigured GPOWrapper::GetConfiguredFancyZonesEnabledValue()
     {
         return static_cast<GpoRuleConfigured>(powertoys_gpo::getConfiguredFancyZonesEnabledValue());

src/common/GPOWrapper/GPOWrapper.h

@@ -13,6 +13,7 @@ namespace winrt::PowerToys::GPOWrapper::implementation
         static GpoRuleConfigured GetConfiguredCmdPalEnabledValue();
         static GpoRuleConfigured GetConfiguredColorPickerEnabledValue();
         static GpoRuleConfigured GetConfiguredCropAndLockEnabledValue();
+        static GpoRuleConfigured GetConfiguredLightSwitchEnabledValue();
         static GpoRuleConfigured GetConfiguredFancyZonesEnabledValue();
         static GpoRuleConfigured GetConfiguredFileLocksmithEnabledValue();
         static GpoRuleConfigured GetConfiguredSvgPreviewEnabledValue();

src/common/GPOWrapper/GPOWrapper.idl

@@ -17,6 +17,7 @@ namespace PowerToys
             static GpoRuleConfigured GetConfiguredCmdPalEnabledValue();
             static GpoRuleConfigured GetConfiguredColorPickerEnabledValue();
             static GpoRuleConfigured GetConfiguredCropAndLockEnabledValue();
+            static GpoRuleConfigured GetConfiguredLightSwitchEnabledValue();
             static GpoRuleConfigured GetConfiguredFancyZonesEnabledValue();
             static GpoRuleConfigured GetConfiguredFileLocksmithEnabledValue();
             static GpoRuleConfigured GetConfiguredSvgPreviewEnabledValue();

src/common/ManagedCommon/ModuleType.cs

@@ -12,6 +12,7 @@ namespace ManagedCommon
         ColorPicker,
         CmdPal,
         CropAndLock,
+        LightSwitch,
         EnvironmentVariables,
         FancyZones,
         FileLocksmith,

src/common/logger/logger_settings.h

@@ -81,6 +81,7 @@ struct LogSettings
     inline const static std::string workspacesSnapshotToolLoggerName = "workspaces-snapshot-tool";
     inline const static std::wstring workspacesSnapshotToolLogPath = L"workspaces-snapshot-tool-log.log";
     inline const static std::string zoomItLoggerName = "zoom-it";
+    inline const static std::string lightSwitchLoggerName = "light-switch";
     inline const static int retention = 30;
     std::wstring logLevel;
     LogSettings();

src/common/utils/elevation.h

@@ -257,7 +257,10 @@ inline HANDLE run_elevated(const std::wstring& file, const std::wstring& params,
         exec_info.nShow = SW_HIDE;
     }
 
-    return ShellExecuteExW(&exec_info) ? exec_info.hProcess : nullptr;
+    // failing bc using "runas" with PowerToys.exe already running?
+    BOOL result = ShellExecuteExW(&exec_info);
+
+    return result  ? exec_info.hProcess : nullptr;
 }
 
 // Run command as non-elevated user, returns true if succeeded, puts the process id into returnPid if returnPid != NULL

src/common/utils/gpo.h

@@ -30,6 +30,7 @@ namespace powertoys_gpo
     const std::wstring POLICY_CONFIGURE_ENABLED_CMD_NOT_FOUND = L"ConfigureEnabledUtilityCmdNotFound";
     const std::wstring POLICY_CONFIGURE_ENABLED_COLOR_PICKER = L"ConfigureEnabledUtilityColorPicker";
     const std::wstring POLICY_CONFIGURE_ENABLED_CROP_AND_LOCK = L"ConfigureEnabledUtilityCropAndLock";
+    const std::wstring POLICY_CONFIGURE_ENABLED_LIGHT_SWITCH = L"ConfigureEnabledUtilityLightSwitch";
     const std::wstring POLICY_CONFIGURE_ENABLED_FANCYZONES = L"ConfigureEnabledUtilityFancyZones";
     const std::wstring POLICY_CONFIGURE_ENABLED_FILE_LOCKSMITH = L"ConfigureEnabledUtilityFileLocksmith";
     const std::wstring POLICY_CONFIGURE_ENABLED_SVG_PREVIEW = L"ConfigureEnabledUtilityFileExplorerSVGPreview";
@@ -295,6 +296,11 @@ namespace powertoys_gpo
         return getUtilityEnabledValue(POLICY_CONFIGURE_ENABLED_CROP_AND_LOCK);
     }
 
+    inline gpo_rule_configured_t getConfiguredLightSwitchEnabledValue()
+    {
+        return getUtilityEnabledValue(POLICY_CONFIGURE_ENABLED_LIGHT_SWITCH);
+    }
+
     inline gpo_rule_configured_t getConfiguredFancyZonesEnabledValue()
     {
         return getUtilityEnabledValue(POLICY_CONFIGURE_ENABLED_FANCYZONES);

src/common/utils/logger_helper.h

@@ -3,6 +3,7 @@
 #include <filesystem>
 #include <common/version/version.h>
 #include <common/SettingsAPI/settings_helpers.h>
+#include <common/logger/logger_settings.h>
 
 namespace LoggerHelpers
 {

src/gpo/assets/PowerToys.admx

@@ -137,6 +137,16 @@
         <decimal value="0" />
       </disabledValue>
     </policy>
+    <policy name="ConfigureEnabledUtilityLightSwitch" class="Both" displayName="$(string.ConfigureEnabledUtilityLightSwitch)" explainText="$(string.ConfigureEnabledUtilityDescription)" key="Software\Policies\PowerToys" valueName="ConfigureEnabledUtilityLightSwitch">
+      <parentCategory ref="PowerToys" />
+      <supportedOn ref="SUPPORTED_POWERTOYS_0_90_0" />
+      <enabledValue>
+        <decimal value="1" />
+      </enabledValue>
+      <disabledValue>
+        <decimal value="0" />
+      </disabledValue>
+    </policy>
     <policy name="ConfigureEnabledUtilityEnvironmentVariables" class="Both" displayName="$(string.ConfigureEnabledUtilityEnvironmentVariables)" explainText="$(string.ConfigureEnabledUtilityDescription)" key="Software\Policies\PowerToys" valueName="ConfigureEnabledUtilityEnvironmentVariables">
       <parentCategory ref="PowerToys" />
       <supportedOn ref="SUPPORTED_POWERTOYS_0_75_0" />

src/gpo/assets/en-US/PowerToys.adml

@@ -245,6 +245,7 @@ If you don't configure this policy, the user will be able to control the setting
       <string id="ConfigureEnabledUtilityCmdNotFound">Command Not Found: Configure enabled state</string>
       <string id="ConfigureEnabledUtilityCmdPal">CmdPal: Configure enabled state</string>
       <string id="ConfigureEnabledUtilityCropAndLock">Crop And Lock: Configure enabled state</string>
+      <string id="ConfigureEnabledUtilityLightSwitch">Light Switch: Configure enabled state</string>
       <string id="ConfigureEnabledUtilityEnvironmentVariables">Environment Variables: Configure enabled state</string>
       <string id="ConfigureEnabledUtilityFancyZones">FancyZones: Configure enabled state</string>
       <string id="ConfigureEnabledUtilityFileLocksmith">File Locksmith: Configure enabled state</string>

src/modules/Hosts/Hosts.Tests/HostsServiceTest.cs

@@ -298,5 +298,34 @@ namespace Hosts.Tests
             var hidden = fileSystem.FileInfo.New(service.HostsFilePath).Attributes.HasFlag(FileAttributes.Hidden);
             Assert.IsTrue(hidden);
         }
+
+        [TestMethod]
+        public async Task NoLeadingSpaces_Disabled_RemovesIndent()
+        {
+            var content =
+        @"10.1.1.1 host host.local # comment
+10.1.1.2 host2 host2.local # another comment
+";
+
+            var expected =
+        @"10.1.1.1  host host.local     # comment
+10.1.1.2  host2 host2.local   # another comment
+# 10.1.1.30 host30 host30.local # new entry
+";
+
+            var fs = new CustomMockFileSystem();
+            var settings = new Mock<IUserSettings>();
+            settings.Setup(s => s.NoLeadingSpaces).Returns(true);
+            var svc = new HostsService(fs, settings.Object, _elevationHelper.Object);
+            fs.AddFile(svc.HostsFilePath, new MockFileData(content));
+
+            var data = await svc.ReadAsync();
+            var entries = data.Entries.ToList();
+            entries.Add(new Entry(0, "10.1.1.30", "host30 host30.local", "new entry", false));
+            await svc.WriteAsync(data.AdditionalLines, entries);
+
+            var result = fs.GetFile(svc.HostsFilePath);
+            Assert.AreEqual(expected, result.TextContents);
+        }
     }
 }

src/modules/Hosts/Hosts/Settings/UserSettings.cs

@@ -26,6 +26,8 @@ namespace Hosts.Settings
 
         private bool _loopbackDuplicates;
 
+        public bool NoLeadingSpaces { get; private set; }
+
         public bool LoopbackDuplicates
         {
             get => _loopbackDuplicates;
@@ -88,6 +90,7 @@ namespace Hosts.Settings
                             AdditionalLinesPosition = (HostsAdditionalLinesPosition)settings.Properties.AdditionalLinesPosition;
                             Encoding = (HostsEncoding)settings.Properties.Encoding;
                             LoopbackDuplicates = settings.Properties.LoopbackDuplicates;
+                            NoLeadingSpaces = settings.Properties.NoLeadingSpaces;
                         }
 
                         retry = false;

src/modules/Hosts/HostsUILib/Helpers/HostsService.cs

@@ -157,7 +157,7 @@ namespace HostsUILib.Helpers
                         {
                             lineBuilder.Append('#').Append(' ');
                         }
-                        else if (anyDisabled)
+                        else if (anyDisabled && !_userSettings.NoLeadingSpaces)
                         {
                             lineBuilder.Append(' ').Append(' ');
                         }

src/modules/Hosts/HostsUILib/Settings/IUserSettings.cs

@@ -19,5 +19,7 @@ namespace HostsUILib.Settings
         event EventHandler LoopbackDuplicatesChanged;
 
         public delegate void OpenSettingsFunction();
+
+        public bool NoLeadingSpaces { get; }
     }
 }

src/modules/LightSwitch/LightSwitchModuleInterface/LightSwitchModuleInterface.rc

@@ -0,0 +1,32 @@
+1 VERSIONINFO
+ FILEVERSION 0,1,0,0
+ PRODUCTVERSION 0,1,0,0
+ FILEFLAGSMASK 0x3fL
+#ifdef _DEBUG
+ FILEFLAGS 0x1L
+#else
+ FILEFLAGS 0x0L
+#endif
+ FILEOS 0x40004L
+ FILETYPE 0x2L
+ FILESUBTYPE 0x0L
+BEGIN
+    BLOCK "StringFileInfo"
+    BEGIN
+        BLOCK "040904b0"
+        BEGIN
+            VALUE "CompanyName", "Company Name"
+            VALUE "FileDescription", "Light Switch Module"
+            VALUE "FileVersion", "0.1.0.0"
+            VALUE "InternalName", "Light Switch"
+            VALUE "LegalCopyright", "Copyright (C) 2019 Company Name"
+            VALUE "OriginalFilename", "PowerToys.LightSwitchModuleInterface.dll"
+            VALUE "ProductName", "Light Switch"
+            VALUE "ProductVersion", "0.1.0.0"
+        END
+    END
+    BLOCK "VarFileInfo"
+    BEGIN
+        VALUE "Translation", 0x409, 1200
+    END
+END

src/modules/LightSwitch/LightSwitchModuleInterface/LightSwitchModuleInterface.sln

@@ -0,0 +1,25 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.14.36127.28 d17.14
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "LightSwitchModuleInterface", "LightSwitchModuleInterface.vcxproj", "{38177D56-6AD1-4ADF-88C9-2843A7932166}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|x64 = Debug|x64
+		Release|x64 = Release|x64
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Debug|x64.ActiveCfg = Debug|x64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Debug|x64.Build.0 = Debug|x64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Release|x64.ActiveCfg = Release|x64
+		{38177D56-6AD1-4ADF-88C9-2843A7932166}.Release|x64.Build.0 = Release|x64
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {FAF634A3-0D98-4A45-B082-D93B59782572}
+	EndGlobalSection
+EndGlobal

src/modules/LightSwitch/LightSwitchModuleInterface/LightSwitchModuleInterface.vcxproj

@@ -0,0 +1,229 @@
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+  <Import Project="..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props" Condition="Exists('..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props')" />
+  <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug|x64">
+      <Configuration>Debug</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|x64">
+      <Configuration>Release</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
+  </ItemGroup>
+  <PropertyGroup Label="Globals">
+    <VCProjectVersion>15.0</VCProjectVersion>
+    <ProjectGuid>{38177d56-6ad1-4adf-88c9-2843a7932166}</ProjectGuid>
+    <Keyword>Win32Proj</Keyword>
+    <RootNamespace>LightSwitchModuleInterface</RootNamespace>
+    <WindowsTargetPlatformVersion>10.0</WindowsTargetPlatformVersion>
+    <ProjectName>LightSwitchModuleInterface</ProjectName>
+    <TargetName>PowerToys.LightSwitchModuleInterface</TargetName>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
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+    <ConfigurationType>DynamicLibrary</ConfigurationType>
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <PlatformToolset>v142</PlatformToolset>
+    <CharacterSet>Unicode</CharacterSet>
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+    <ClInclude Include="resource.h" />
+    <ClInclude Include="ThemeHelper.h" />
+    <ClInclude Include="trace.h" />
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="dllmain.cpp" />
+    <ClCompile Include="pch.cpp">
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|x64'">Create</PrecompiledHeader>
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+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">Create</PrecompiledHeader>
+      <PrecompiledHeaderFile Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">pch.h</PrecompiledHeaderFile>
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+    </ClCompile>
+    <ClCompile Include="ThemeHelper.cpp" />
+    <ClCompile Include="trace.cpp" />
+  </ItemGroup>
+  <ItemGroup>
+    <ResourceCompile Include="LightSwitchModuleInterface.rc" />
+  </ItemGroup>
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+  </ImportGroup>
+  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
+    <PropertyGroup>
+      <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
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src/modules/LightSwitch/LightSwitchModuleInterface/LightSwitchModuleInterface.vcxproj.filters

@@ -0,0 +1,50 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <ClCompile Include="dllmain.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="pch.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="trace.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="ThemeHelper.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="pch.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="resource.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="trace.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="ThemeHelper.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+  </ItemGroup>
+  <ItemGroup>
+    <Filter Include="Header Files">
+      <UniqueIdentifier>{bbf22ac8-46f8-4206-b44b-9c3897e99ce5}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="Source Files">
+      <UniqueIdentifier>{530ed784-9a70-46a0-8fb6-20d5dee4f7d3}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="Resource Files">
+      <UniqueIdentifier>{da1cb871-86d3-414c-adf5-a7e9f2077d2f}</UniqueIdentifier>
+    </Filter>
+  </ItemGroup>
+  <ItemGroup>
+    <ResourceCompile Include="LightSwitchModuleInterface.rc">
+      <Filter>Resource Files</Filter>
+    </ResourceCompile>
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
+</Project>

src/modules/LightSwitch/LightSwitchModuleInterface/ThemeHelper.cpp

@@ -0,0 +1,81 @@
+#include "pch.h"
+#include <windows.h>
+#include "ThemeHelper.h"
+
+// Controls changing the themes.
+
+void SetAppsTheme(bool mode)
+{
+    HKEY hKey;
+    if (RegOpenKeyEx(HKEY_CURRENT_USER,
+                     L"Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize",
+                     0,
+                     KEY_SET_VALUE,
+                     &hKey) == ERROR_SUCCESS)
+    {
+        DWORD value = mode;
+        RegSetValueEx(hKey, L"AppsUseLightTheme", 0, REG_DWORD, reinterpret_cast<const BYTE*>(&value), sizeof(value));
+        RegCloseKey(hKey);
+
+        SendMessageTimeout(HWND_BROADCAST, WM_SETTINGCHANGE, 0, reinterpret_cast<LPARAM>(L"ImmersiveColorSet"), SMTO_ABORTIFHUNG, 5000, nullptr);
+
+        SendMessageTimeout(HWND_BROADCAST, WM_THEMECHANGED, 0, 0, SMTO_ABORTIFHUNG, 5000, nullptr);
+    }
+}
+
+void SetSystemTheme(bool mode)
+{
+    HKEY hKey;
+    if (RegOpenKeyEx(HKEY_CURRENT_USER,
+                     L"Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize",
+                     0,
+                     KEY_SET_VALUE,
+                     &hKey) == ERROR_SUCCESS)
+    {
+        DWORD value = mode;
+        RegSetValueEx(hKey, L"SystemUsesLightTheme", 0, REG_DWORD, reinterpret_cast<const BYTE*>(&value), sizeof(value));
+        RegCloseKey(hKey);
+
+        SendMessageTimeout(HWND_BROADCAST, WM_SETTINGCHANGE, 0, reinterpret_cast<LPARAM>(L"ImmersiveColorSet"), SMTO_ABORTIFHUNG, 5000, nullptr);
+
+        SendMessageTimeout(HWND_BROADCAST, WM_THEMECHANGED, 0, 0, SMTO_ABORTIFHUNG, 5000, nullptr);
+    }
+}
+
+bool GetCurrentSystemTheme()
+{
+    HKEY hKey;
+    DWORD value = 1; // default = light
+    DWORD size = sizeof(value);
+
+    if (RegOpenKeyEx(HKEY_CURRENT_USER,
+                     L"Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize",
+                     0,
+                     KEY_READ,
+                     &hKey) == ERROR_SUCCESS)
+    {
+        RegQueryValueEx(hKey, L"SystemUsesLightTheme", nullptr, nullptr, reinterpret_cast<LPBYTE>(&value), &size);
+        RegCloseKey(hKey);
+    }
+
+    return value == 0; // 0 = dark, 1 = light
+}
+
+bool GetCurrentAppsTheme()
+{
+    HKEY hKey;
+    DWORD value = 1;
+    DWORD size = sizeof(value);
+
+    if (RegOpenKeyEx(HKEY_CURRENT_USER,
+                     L"Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize",
+                     0,
+                     KEY_READ,
+                     &hKey) == ERROR_SUCCESS)
+    {
+        RegQueryValueEx(hKey, L"SystemUsesLightTheme", nullptr, nullptr, reinterpret_cast<LPBYTE>(&value), &size);
+        RegCloseKey(hKey);
+    }
+
+    return value == 0;
+}

src/modules/LightSwitch/LightSwitchModuleInterface/ThemeHelper.h

@@ -0,0 +1,5 @@
+#pragma once
+void SetSystemTheme(bool dark);
+void SetAppsTheme(bool dark);
+bool GetCurrentSystemTheme();
+bool GetCurrentAppsTheme();

src/modules/LightSwitch/LightSwitchModuleInterface/dllmain.cpp

@@ -0,0 +1,669 @@
+#include "pch.h"
+#include <interface/powertoy_module_interface.h>
+#include "trace.h"
+#include <common/logger/logger.h>
+#include <common/SettingsAPI/settings_objects.h>
+#include <common/SettingsAPI/settings_helpers.h>
+#include <locale>
+#include <codecvt>
+#include <common/utils/logger_helper.h>
+#include "ThemeHelper.h"
+
+extern "C" IMAGE_DOS_HEADER __ImageBase;
+
+namespace
+{
+    const wchar_t JSON_KEY_PROPERTIES[] = L"properties";
+    const wchar_t JSON_KEY_WIN[] = L"win";
+    const wchar_t JSON_KEY_ALT[] = L"alt";
+    const wchar_t JSON_KEY_CTRL[] = L"ctrl";
+    const wchar_t JSON_KEY_SHIFT[] = L"shift";
+    const wchar_t JSON_KEY_CODE[] = L"code";
+    const wchar_t JSON_KEY_FORCE_LIGHT_HOTKEY[] = L"force-light-mode-hotkey";
+    const wchar_t JSON_KEY_FORCE_DARK_HOTKEY[] = L"force-dark-mode-hotkey";
+    const wchar_t JSON_KEY_VALUE[] = L"value";
+}
+
+BOOL APIENTRY DllMain(HMODULE hModule, DWORD ul_reason_for_call, LPVOID lpReserved)
+{
+    switch (ul_reason_for_call)
+    {
+    case DLL_PROCESS_ATTACH:
+        Trace::RegisterProvider();
+        break;
+    case DLL_THREAD_ATTACH:
+    case DLL_THREAD_DETACH:
+        break;
+    case DLL_PROCESS_DETACH:
+        Trace::UnregisterProvider();
+        break;
+    }
+    return TRUE;
+}
+
+// The PowerToy name that will be shown in the settings.
+const static wchar_t* MODULE_NAME = L"LightSwitch";
+// Add a description that will we shown in the module settings page.
+const static wchar_t* MODULE_DESC = L"This is a module that allows you to control light/dark theming via set times, sun rise, or directly invoking the change.";
+
+enum class ScheduleMode
+{
+    FixedHours,
+    SunsetToSunriseGeo,
+    SunsetToSunriseUser
+    // add more later
+};
+
+inline std::wstring ToString(ScheduleMode mode)
+{
+    switch (mode)
+    {
+    case ScheduleMode::SunsetToSunriseGeo:
+        return L"SunsetToSunriseGeo";
+    case ScheduleMode::SunsetToSunriseUser:
+        return L"SunsetToSunriseUser";
+    case ScheduleMode::FixedHours:
+    default:
+        return L"FixedHours";
+    }
+}
+
+inline ScheduleMode FromString(const std::wstring& str)
+{
+    if (str == L"SunsetToSunriseGeo")
+        return ScheduleMode::SunsetToSunriseGeo;
+    if (str == L"SunsetToSunriseUser")
+        return ScheduleMode::SunsetToSunriseUser;
+    return ScheduleMode::FixedHours;
+}
+
+// These are the properties shown in the Settings page.
+struct ModuleSettings
+{
+    bool m_changeSystem = true;
+    bool m_changeApps = true;
+    ScheduleMode m_scheduleMode = ScheduleMode::FixedHours;
+    int m_lightTime = 480;
+    int m_darkTime = 1200;
+    int m_offset = 0;
+    std::wstring m_latitude = L"0.0";
+    std::wstring m_longitude = L"0.0";
+} g_settings;
+
+// Implement the PowerToy Module Interface and all the required methods.
+class LightSwitchInterface : public PowertoyModuleIface
+{
+private:
+    // The PowerToy state.
+    bool m_enabled = false;
+
+    HANDLE m_process{ nullptr };
+    HANDLE m_force_light_event_handle;
+    HANDLE m_force_dark_event_handle;
+
+    static const constexpr int NUM_DEFAULT_HOTKEYS = 4;
+
+    Hotkey m_force_light_mode_hotkey = { .win = true, .ctrl = true, .shift = true, .alt = false, .key = 'L' };
+    Hotkey m_force_dark_mode_hotkey = { .win = true, .ctrl = true, .shift = true, .alt = false, .key = 'D' };
+
+    // Load initial settings from the persisted values.
+    void init_settings();
+
+public:
+    // Constructor
+    LightSwitchInterface()
+    {
+        LoggerHelpers::init_logger(L"LightSwitch", L"ModuleInterface", LogSettings::lightSwitchLoggerName);
+
+        m_force_light_event_handle = CreateDefaultEvent(L"POWEROYS_LIGHTSWITCH_FORCE_LIGHT");
+        m_force_dark_event_handle = CreateDefaultEvent(L"POWEROYS_LIGHTSWITCH_FORCE_DARK");
+
+        init_settings();
+    };
+
+    virtual const wchar_t* get_key() override
+    {
+        return L"LightSwitch"; // your unique key string
+    }
+
+    // Destroy the powertoy and free memory
+    virtual void destroy() override
+    {
+        delete this;
+    }
+
+    // Return the display name of the powertoy, this will be cached by the runner
+    virtual const wchar_t* get_name() override
+    {
+        return MODULE_NAME;
+    }
+
+    // Return the configured status for the gpo policy for the module
+    virtual powertoys_gpo::gpo_rule_configured_t gpo_policy_enabled_configuration() override
+    {
+        return powertoys_gpo::getConfiguredLightSwitchEnabledValue();
+    }
+
+    // Return array of the names of all events that this powertoy listens for, with
+    // nullptr as the last element of the array. Nullptr can also be retured for empty
+    // list.
+    //virtual const wchar_t** get_events() override
+    //{
+    //    static const wchar_t* events[] = { nullptr };
+    //    // Available events:
+    //    // - ll_keyboard
+    //    // - win_hook_event
+    //    //
+    //    // static const wchar_t* events[] = { ll_keyboard,
+    //    //                                   win_hook_event,
+    //    //                                   nullptr };
+
+    //    return events;
+    //}
+
+    // Return JSON with the configuration options.
+    virtual bool get_config(wchar_t* buffer, int* buffer_size) override
+    {
+        HINSTANCE hinstance = reinterpret_cast<HINSTANCE>(&__ImageBase);
+
+        // Create a Settings object with your module name
+        PowerToysSettings::Settings settings(hinstance, get_name());
+        settings.set_description(MODULE_DESC);
+        settings.set_overview_link(L"https://aka.ms/powertoys");
+
+        // Boolean toggles
+        settings.add_bool_toggle(
+            L"changeSystem",
+            L"Change System Theme",
+            g_settings.m_changeSystem);
+
+        settings.add_bool_toggle(
+            L"changeApps",
+            L"Change Apps Theme",
+            g_settings.m_changeApps);
+
+        settings.add_choice_group(
+            L"scheduleMode",
+            L"Theme schedule mode",
+            ToString(g_settings.m_scheduleMode),
+            { { L"FixedHours", L"Set hours manually" },
+              { L"SunsetToSunriseGeo", L"Use sunrise/sunset times (Geolocation)" },
+              { L"SunsetToSunriseUser", L"Use sunrise/sunset times (User selected)" } });
+
+        // Integer spinners (for time in minutes since midnight)
+        settings.add_int_spinner(
+            L"lightTime",
+            L"Time to switch to light theme (minutes after midnight).",
+            g_settings.m_lightTime,
+            0,
+            1439,
+            1);
+
+        settings.add_int_spinner(
+            L"darkTime",
+            L"Time to switch to dark theme (minutes after midnight).",
+            g_settings.m_darkTime,
+            0,
+            1439,
+            1);
+
+        settings.add_int_spinner(
+            L"offset",
+            L"Time to offset turning on your light/dark themes.",
+            g_settings.m_offset,
+            0,
+            1439,
+            1);
+
+        // Strings for latitude and longitude
+        settings.add_string(
+            L"latitude",
+            L"Your latitude in decimal degrees (e.g. 39.95).",
+            g_settings.m_latitude);
+
+        settings.add_string(
+            L"longitude",
+            L"Your longitude in decimal degrees (e.g. -75.16).",
+            g_settings.m_longitude);
+
+        // One-shot actions (buttons)
+        settings.add_custom_action(
+            L"forceLight",
+            L"Switch immediately to light theme",
+            L"Force Light",
+            L"{}");
+
+        settings.add_custom_action(
+            L"forceDark",
+            L"Switch immediately to dark theme",
+            L"Force Dark",
+            L"{}");
+
+        PowerToysSettings::HotkeyObject lm_hk = PowerToysSettings::HotkeyObject::from_settings(
+            m_force_light_mode_hotkey.win,
+            m_force_light_mode_hotkey.ctrl,
+            m_force_light_mode_hotkey.alt,
+            m_force_light_mode_hotkey.shift,
+            m_force_light_mode_hotkey.key);
+
+        settings.add_hotkey(
+            L"force-light-hotkey",
+            L"Shortcut to force light theme immediately",
+            lm_hk);
+
+        PowerToysSettings::HotkeyObject dm_hk = PowerToysSettings::HotkeyObject::from_settings(
+            m_force_dark_mode_hotkey.win,
+            m_force_dark_mode_hotkey.ctrl,
+            m_force_dark_mode_hotkey.alt,
+            m_force_dark_mode_hotkey.shift,
+            m_force_dark_mode_hotkey.key);
+
+        settings.add_hotkey(
+            L"force-dark-hotkey",
+            L"Shortcut to force dark theme immediately",
+            dm_hk);
+
+        // Serialize to buffer for the PowerToys runner
+        return settings.serialize_to_buffer(buffer, buffer_size);
+    }
+
+    // Signal from the Settings editor to call a custom action.
+    // This can be used to spawn more complex editors.
+    void call_custom_action(const wchar_t* action) override
+    {
+        try
+        {
+            auto action_object = PowerToysSettings::CustomActionObject::from_json_string(action);
+
+            if (action_object.get_name() == L"forceLight")
+            {
+                Logger::info(L"[Light Switch] Custom action triggered: Force Light");
+                SetSystemTheme(true);
+                SetAppsTheme(true);
+            }
+            else if (action_object.get_name() == L"forceDark")
+            {
+                Logger::info(L"[Light Switch] Custom action triggered: Force Dark");
+                SetSystemTheme(false);
+                SetAppsTheme(false);
+            }
+        }
+        catch (...)
+        {
+            Logger::error(L"[Light Switch] Invalid custom action JSON");
+        }
+    }
+
+    // Called by the runner to pass the updated settings values as a serialized JSON.
+    virtual void set_config(const wchar_t* config) override
+    {
+        try
+        {
+            auto values = PowerToysSettings::PowerToyValues::from_json_string(config, get_key());
+
+            parse_hotkey(values);
+
+            if (auto v = values.get_bool_value(L"changeSystem"))
+            {
+                g_settings.m_changeSystem = *v;
+            }
+
+            if (auto v = values.get_bool_value(L"changeApps"))
+            {
+                g_settings.m_changeApps = *v;
+            }
+
+            if (auto v = values.get_string_value(L"scheduleMode"))
+            {
+                g_settings.m_scheduleMode = FromString(*v);
+            }
+
+            if (auto v = values.get_int_value(L"lightTime"))
+            {
+                g_settings.m_lightTime = *v;
+            }
+
+            if (auto v = values.get_int_value(L"darkTime"))
+            {
+                g_settings.m_darkTime = *v;
+            }
+
+            if (auto v = values.get_int_value(L"offset"))
+            {
+                g_settings.m_offset = *v;
+            }
+
+            if (auto v = values.get_string_value(L"latitude"))
+            {
+                g_settings.m_latitude = *v;
+            }
+            if (auto v = values.get_string_value(L"longitude"))
+            {
+                g_settings.m_longitude = *v;
+            }
+            
+
+            values.save_to_settings_file();
+        }
+        catch (const std::exception&)
+        {
+            Logger::error("[Light Switch] set_config: Failed to parse or apply config.");
+        }
+    }
+
+    virtual void enable()
+    {
+        m_enabled = true;
+        Logger::info(L"Enabling Light Switch module...");
+
+        unsigned long powertoys_pid = GetCurrentProcessId();
+        std::wstring args = L"--pid " + std::to_wstring(powertoys_pid);
+        std::wstring exe_name = L"LightSwitchService\\PowerToys.LightSwitchService.exe";
+
+        // Resolve the executable path
+        std::wstring resolved_path(MAX_PATH, L'\0');
+        DWORD result = SearchPathW(
+            nullptr,
+            exe_name.c_str(),
+            nullptr,
+            static_cast<DWORD>(resolved_path.size()),
+            resolved_path.data(),
+            nullptr);
+
+        if (result == 0 || result >= resolved_path.size())
+        {
+            Logger::error(L"Failed to locate Light Switch executable: '{}'", exe_name);
+            return;
+        }
+
+        resolved_path.resize(result);
+        Logger::debug(L"Resolved executable path: {}", resolved_path);
+
+        std::wstring command_line = L"\"" + resolved_path + L"\" " + args;
+
+        STARTUPINFO si = { sizeof(si) };
+        PROCESS_INFORMATION pi;
+
+        if (!CreateProcessW(
+                resolved_path.c_str(), // lpApplicationName
+                command_line.data(), // lpCommandLine (must be mutable)
+                nullptr,
+                nullptr,
+                TRUE,
+                0,
+                nullptr,
+                nullptr,
+                &si,
+                &pi))
+        {
+            Logger::error(L"Failed to launch Light Switch process. {}", get_last_error_or_default(GetLastError()));
+            return;
+        }
+
+        Logger::info(L"Light Switch process launched successfully (PID: {}).", pi.dwProcessId);
+        m_process = pi.hProcess;
+        CloseHandle(pi.hThread);
+    }
+
+    // Disable the powertoy
+    virtual void disable()
+    {
+        Logger::info("Light Switch disabling");
+        m_enabled = false;
+
+        if (m_process)
+        {
+            // Try waiting briefly to allow graceful exit, if needed
+            constexpr DWORD timeout_ms = 1500;
+            DWORD result = WaitForSingleObject(m_process, timeout_ms);
+
+            if (result == WAIT_TIMEOUT)
+            {
+                // Force kill if it didn<64>t exit in time
+                Logger::warn("Light Switch: Process didn't exit in time. Forcing termination.");
+                TerminateProcess(m_process, 0);
+            }
+
+            // Always clean up the handle
+            CloseHandle(m_process);
+            m_process = nullptr;
+        }
+    }
+
+    // Returns if the powertoys is enabled
+    virtual bool is_enabled() override
+    {
+        return m_enabled;
+    }
+
+    void parse_hotkey(PowerToysSettings::PowerToyValues& settings)
+    {
+        auto settingsObject = settings.get_raw_json();
+        if (settingsObject.GetView().Size())
+        {
+            try
+            {
+                Hotkey _temp_force_light;
+                auto jsonHotkeyObject = settingsObject.GetNamedObject(JSON_KEY_PROPERTIES).GetNamedObject(JSON_KEY_FORCE_LIGHT_HOTKEY).GetNamedObject(JSON_KEY_VALUE);
+                _temp_force_light.win = jsonHotkeyObject.GetNamedBoolean(JSON_KEY_WIN);
+                _temp_force_light.alt = jsonHotkeyObject.GetNamedBoolean(JSON_KEY_ALT);
+                _temp_force_light.shift = jsonHotkeyObject.GetNamedBoolean(JSON_KEY_SHIFT);
+                _temp_force_light.ctrl = jsonHotkeyObject.GetNamedBoolean(JSON_KEY_CTRL);
+                _temp_force_light.key = static_cast<unsigned char>(jsonHotkeyObject.GetNamedNumber(JSON_KEY_CODE));
+                m_force_light_mode_hotkey = _temp_force_light;
+            }
+            catch (...)
+            {
+                Logger::error("Failed to initialize Light Switch force light mode shortcut from settings. Value will keep unchanged.");
+            }
+            try
+            {
+                Hotkey _temp_force_dark;
+                auto jsonHotkeyObject = settingsObject.GetNamedObject(JSON_KEY_PROPERTIES).GetNamedObject(JSON_KEY_FORCE_DARK_HOTKEY).GetNamedObject(JSON_KEY_VALUE);
+                _temp_force_dark.win = jsonHotkeyObject.GetNamedBoolean(JSON_KEY_WIN);
+                _temp_force_dark.alt = jsonHotkeyObject.GetNamedBoolean(JSON_KEY_ALT);
+                _temp_force_dark.shift = jsonHotkeyObject.GetNamedBoolean(JSON_KEY_SHIFT);
+                _temp_force_dark.ctrl = jsonHotkeyObject.GetNamedBoolean(JSON_KEY_CTRL);
+                _temp_force_dark.key = static_cast<unsigned char>(jsonHotkeyObject.GetNamedNumber(JSON_KEY_CODE));
+                m_force_dark_mode_hotkey = _temp_force_dark;
+            }
+            catch (...)
+            {
+                Logger::error("Failed to initialize Light Switch force dark mode shortcut from settings. Value will keep unchanged.");
+            }
+        }
+        else
+        {
+            Logger::info("Light Switch settings are empty");
+        }
+    }
+
+    virtual size_t get_hotkeys(Hotkey* hotkeys, size_t buffer_size) override
+    {
+        if (hotkeys && buffer_size >= 2)
+        {
+            hotkeys[0] = m_force_light_mode_hotkey;
+            hotkeys[1] = m_force_dark_mode_hotkey;
+        }
+        return 2;
+    }
+
+    virtual bool on_hotkey(size_t hotkeyId) override
+    {
+        if (m_enabled)
+        {
+            Logger::trace(L"Light Switch hotkey pressed");
+            if (!is_process_running())
+            {
+                enable();
+            }
+
+            if (hotkeyId == 0)
+            {
+                Logger::info(L"[Light Switch] Hotkey triggered: Force Light");
+                SetSystemTheme(true);
+                SetAppsTheme(true);
+            }
+            else if (hotkeyId == 1)
+            {
+                Logger::info(L"[Light Switch] Hotkey triggered: Force Dark");
+                SetSystemTheme(false);
+                SetAppsTheme(false);
+            }
+
+            return true;
+        }
+
+        return false;
+    }
+
+    bool is_process_running()
+    {
+        return WaitForSingleObject(m_process, 0) == WAIT_TIMEOUT;
+    }
+
+    // Handle incoming event, data is event-specific
+    //virtual intptr_t signal_event(const wchar_t* name, intptr_t data) override
+    //{
+    //    if (wcscmp(name, ll_keyboard) == 0)
+    //    {
+    //        auto& event = *(reinterpret_cast<LowlevelKeyboardEvent*>(data));
+    //        // Return 1 if the keypress is to be suppressed (not forwarded to Windows),
+    //        // otherwise return 0.
+    //        return 0;
+    //    }
+    //    else if (wcscmp(name, win_hook_event) == 0)
+    //    {
+    //        auto& event = *(reinterpret_cast<WinHookEvent*>(data));
+    //        // Return value is ignored
+    //        return 0;
+    //    }
+    //    return 0;
+    //}
+
+    //// This methods are part of an experimental features not fully supported yet
+    //virtual void register_system_menu_helper(PowertoySystemMenuIface* helper) override
+    //{
+    //}
+
+    //virtual void signal_system_menu_action(const wchar_t* name) override
+    //{
+    //}
+};
+
+std::wstring utf8_to_wstring(const std::string& str)
+{
+    if (str.empty())
+        return std::wstring();
+
+    int size_needed = MultiByteToWideChar(
+        CP_UTF8,
+        0,
+        str.c_str(),
+        static_cast<int>(str.size()),
+        nullptr,
+        0);
+
+    std::wstring wstr(size_needed, 0);
+
+    MultiByteToWideChar(
+        CP_UTF8,
+        0,
+        str.c_str(),
+        static_cast<int>(str.size()),
+        &wstr[0],
+        size_needed);
+
+    return wstr;
+}
+
+// Load the settings file.
+void LightSwitchInterface::init_settings()
+{
+    Logger::info(L"[Light Switch] init_settings: starting to load settings for module");
+
+    try
+    {
+        PowerToysSettings::PowerToyValues settings =
+            PowerToysSettings::PowerToyValues::load_from_settings_file(get_name());
+
+        parse_hotkey(settings);
+
+        if (auto v = settings.get_bool_value(L"changeSystem"))
+            g_settings.m_changeSystem = *v;
+        if (auto v = settings.get_bool_value(L"changeApps"))
+            g_settings.m_changeApps = *v;
+        if (auto v = settings.get_string_value(L"scheduleMode"))
+            g_settings.m_scheduleMode = FromString(*v);
+        if (auto v = settings.get_int_value(L"lightTime"))
+            g_settings.m_lightTime = *v;
+        if (auto v = settings.get_int_value(L"darkTime"))
+            g_settings.m_darkTime = *v;
+        if (auto v = settings.get_int_value(L"offset"))
+            g_settings.m_offset = *v;
+        if (auto v = settings.get_string_value(L"latitude"))
+            g_settings.m_latitude = *v;
+        if (auto v = settings.get_string_value(L"longitude"))
+            g_settings.m_longitude = *v;
+
+        Logger::info(L"[Light Switch] init_settings: loaded successfully");
+    }
+    catch (const winrt::hresult_error& e)
+    {
+        Logger::error(L"[Light Switch] init_settings: hresult_error 0x{:08X} - {}", e.code(), e.message().c_str());
+    }
+    catch (const std::exception& e)
+    {
+        std::wstring whatStr = utf8_to_wstring(e.what());
+        Logger::error(L"[Light Switch] init_settings: std::exception - {}", whatStr);
+    }
+    catch (...)
+    {
+        Logger::error(L"[Light Switch] init_settings: unknown exception while loading settings");
+    }
+}
+
+// This method of saving the module settings is only required if you need to do any
+// custom processing of the settings before saving them to disk.
+//void $projectname$::save_settings() {
+//  try {
+//    // Create a PowerToyValues object for this PowerToy
+//    PowerToysSettings::PowerToyValues values(get_name());
+//
+//    // Save a bool property.
+//    //values.add_property(
+//    //  L"bool_toggle_1", // property name
+//    //  g_settings.bool_prop // property value
+//    //  g_settings.bool_prop // property value
+//    //);
+//
+//    // Save an int property.
+//    //values.add_property(
+//    //  L"int_spinner_1", // property name
+//    //  g_settings.int_prop // property value
+//    //);
+//
+//    // Save a string property.
+//    //values.add_property(
+//    //  L"string_text_1", // property name
+//    //  g_settings.string_prop // property value
+//    );
+//
+//    // Save a color property.
+//    //values.add_property(
+//    //  L"color_picker_1", // property name
+//    //  g_settings.color_prop // property value
+//    //);
+//
+//    // Save the PowerToyValues JSON to the power toy settings file.
+//    values.save_to_settings_file();
+//  }
+//  catch (std::exception ex) {
+//    // Couldn't save the settings.
+//  }
+//}
+
+extern "C" __declspec(dllexport) PowertoyModuleIface* __cdecl powertoy_create()
+{
+    return new LightSwitchInterface();
+}

src/modules/LightSwitch/LightSwitchModuleInterface/pch.cpp

@@ -0,0 +1,2 @@
+#include "pch.h"
+#pragma comment(lib, "windowsapp")

src/modules/LightSwitch/LightSwitchModuleInterface/pch.h

@@ -0,0 +1,14 @@
+#pragma once
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+#include <common/SettingsAPI/settings_helpers.h>
+#include <common/utils/gpo.h>
+#include <common/utils/winapi_error.h>
+#include <shlwapi.h>
+#include <shellapi.h>
+#include <winrt/Windows.Foundation.h>
+#include <winrt/Windows.System.h>
+#include <winrt/Windows.Globalization.h>
+#include <winrt/Windows.ApplicationModel.h>
+#include <winrt/Windows.ApplicationModel.Core.h>

src/modules/LightSwitch/LightSwitchModuleInterface/trace.cpp

@@ -0,0 +1,30 @@
+#include "pch.h"
+#include "trace.h"
+#include <TraceLoggingProvider.h>
+
+TRACELOGGING_DEFINE_PROVIDER(
+    g_hProvider,
+    "Microsoft.PowerToys",
+    // {38e8889b-9731-53f5-e901-e8a7c1753074}
+    (0x38e8889b, 0x9731, 0x53f5, 0xe9, 0x01, 0xe8, 0xa7, 0xc1, 0x75, 0x30, 0x74),
+    TraceLoggingOptionProjectTelemetry());
+
+void Trace::RegisterProvider()
+{
+    TraceLoggingRegister(g_hProvider);
+}
+
+void Trace::UnregisterProvider()
+{
+    TraceLoggingUnregister(g_hProvider);
+}
+
+void Trace::MyEvent()
+{
+    TraceLoggingWrite(
+        g_hProvider,
+        "PowerToyName_MyEvent",
+        ProjectTelemetryPrivacyDataTag(ProjectTelemetryTag_ProductAndServicePerformance),
+        TraceLoggingBoolean(TRUE, "UTCReplace_AppSessionGuid"),
+        TraceLoggingKeyword(PROJECT_KEYWORD_MEASURE));
+}

src/modules/LightSwitch/LightSwitchModuleInterface/trace.h

@@ -0,0 +1,15 @@
+#pragma once
+
+#include <windows.h>
+#include <TraceLoggingActivity.h>
+#include <common/telemetry/ProjectTelemetry.h>
+
+TRACELOGGING_DECLARE_PROVIDER(g_hProvider);
+
+class Trace
+{
+public:
+    static void RegisterProvider();
+    static void UnregisterProvider();
+    static void MyEvent();
+};

src/modules/LightSwitch/LightSwitchService/LightSwitchService.cpp

@@ -0,0 +1,258 @@
+#include <windows.h>
+#include <tchar.h>
+#include "ThemeScheduler.h"
+#include "ThemeHelper.h"
+#include <stdio.h>
+#include <string>
+#include <LightSwitchSettings.h>
+#include <common/utils/gpo.h>
+
+// Global service variables
+SERVICE_STATUS g_ServiceStatus = {};
+SERVICE_STATUS_HANDLE g_StatusHandle = nullptr;
+HANDLE g_ServiceStopEvent = nullptr;
+
+// Forward declarations of service functions (we<77>ll define them later)
+VOID WINAPI ServiceMain(DWORD argc, LPTSTR* argv);
+VOID WINAPI ServiceCtrlHandler(DWORD dwCtrl);
+DWORD WINAPI ServiceWorkerThread(LPVOID lpParam);
+
+// Entry point for the executable
+int _tmain(int argc, TCHAR* argv[])
+{
+    // Parse args
+    DWORD parentPid = 0;
+    bool debug = false;
+    for (int i = 1; i < argc; ++i)
+    {
+        if (_tcscmp(argv[i], _T("--debug")) == 0)
+            debug = true;
+        else if (_tcscmp(argv[i], _T("--pid")) == 0 && i + 1 < argc)
+            parentPid = _tstoi(argv[++i]);
+    }
+
+    if (debug)
+    {
+        // Create a console window for debug output
+        AllocConsole();
+        FILE* f;
+        freopen_s(&f, "CONOUT$", "w", stdout);
+        freopen_s(&f, "CONOUT$", "w", stderr);
+
+        // Optional: set a title so you can find it easily
+        SetConsoleTitle(L"LightSwitchService Debug");
+
+        // Console mode (debug)
+        g_ServiceStopEvent = CreateEvent(nullptr, TRUE, FALSE, nullptr);
+        ServiceWorkerThread(reinterpret_cast<void*>(static_cast<ULONG_PTR>(parentPid)));
+        CloseHandle(g_ServiceStopEvent);
+
+        // Keep window open until a key is pressed (optional)
+        // system("pause");
+
+        FreeConsole();
+        return 0;
+    }
+
+    // Try to connect to SCM
+    wchar_t serviceName[] = L"LightSwitchService";
+    SERVICE_TABLE_ENTRYW table[] = { { serviceName, ServiceMain }, { nullptr, nullptr } };
+
+    if (!StartServiceCtrlDispatcherW(table))
+    {
+        DWORD err = GetLastError();
+        if (err == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) // not launched by SCM
+        {
+            g_ServiceStopEvent = CreateEvent(nullptr, TRUE, FALSE, nullptr);
+            HANDLE hThread = CreateThread(
+                nullptr, 0, ServiceWorkerThread, reinterpret_cast<void*>(static_cast<ULONG_PTR>(parentPid)), 0, nullptr);
+
+            // Wait so the process stays alive
+            WaitForSingleObject(hThread, INFINITE);
+            CloseHandle(hThread);
+            CloseHandle(g_ServiceStopEvent);
+            return 0;
+        }
+        return static_cast<int>(err);
+    }
+
+    return 0;
+}
+
+// Called when the service is launched by Windows
+VOID WINAPI ServiceMain(DWORD, LPTSTR*)
+{
+    g_StatusHandle = RegisterServiceCtrlHandler(_T("LightSwitchService"), ServiceCtrlHandler);
+    if (!g_StatusHandle)
+        return;
+
+    g_ServiceStatus.dwServiceType = SERVICE_WIN32_OWN_PROCESS;
+    g_ServiceStatus.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
+    g_ServiceStatus.dwCurrentState = SERVICE_START_PENDING;
+    SetServiceStatus(g_StatusHandle, &g_ServiceStatus);
+
+    g_ServiceStopEvent = CreateEvent(nullptr, TRUE, FALSE, nullptr);
+    if (!g_ServiceStopEvent)
+    {
+        g_ServiceStatus.dwCurrentState = SERVICE_STOPPED;
+        g_ServiceStatus.dwWin32ExitCode = GetLastError();
+        SetServiceStatus(g_StatusHandle, &g_ServiceStatus);
+        return;
+    }
+
+    SECURITY_ATTRIBUTES sa{ sizeof(sa) };
+    sa.bInheritHandle = FALSE;
+    sa.lpSecurityDescriptor = nullptr;
+
+    g_ServiceStatus.dwCurrentState = SERVICE_RUNNING;
+    SetServiceStatus(g_StatusHandle, &g_ServiceStatus);
+
+    HANDLE hThread = CreateThread(nullptr, 0, ServiceWorkerThread, nullptr, 0, nullptr);
+    WaitForSingleObject(hThread, INFINITE);
+    CloseHandle(hThread);
+
+    CloseHandle(g_ServiceStopEvent);
+    g_ServiceStatus.dwCurrentState = SERVICE_STOPPED;
+    g_ServiceStatus.dwWin32ExitCode = 0;
+    SetServiceStatus(g_StatusHandle, &g_ServiceStatus);
+}
+
+VOID WINAPI ServiceCtrlHandler(DWORD dwCtrl)
+{
+    switch (dwCtrl)
+    {
+    case SERVICE_CONTROL_STOP:
+        if (g_ServiceStatus.dwCurrentState != SERVICE_RUNNING)
+            break;
+
+        g_ServiceStatus.dwCurrentState = SERVICE_STOP_PENDING;
+        SetServiceStatus(g_StatusHandle, &g_ServiceStatus);
+
+        // Signal the service to stop
+        SetEvent(g_ServiceStopEvent);
+        break;
+
+    default:
+        break;
+    }
+}
+
+DWORD WINAPI ServiceWorkerThread(LPVOID lpParam)
+{
+    DWORD parentPid = static_cast<DWORD>(reinterpret_cast<ULONG_PTR>(lpParam));
+    HANDLE hParent = nullptr;
+    if (parentPid)
+        hParent = OpenProcess(SYNCHRONIZE, FALSE, parentPid);
+
+    OutputDebugString(L"[LightSwitchService] Worker thread starting...\n");
+
+    // Initialize settings system
+    LightSwitchSettings::instance().InitFileWatcher();
+
+    auto applyTheme = [](int nowMinutes, int lightMinutes, int darkMinutes, const auto& settings) {
+        bool isLightActive = false;
+
+        if (lightMinutes < darkMinutes)
+        {
+            // Normal case: sunrise < sunset
+            isLightActive = (nowMinutes >= lightMinutes && nowMinutes < darkMinutes);
+        }
+        else
+        {
+            // Wraparound case: e.g. light at 21:00, dark at 06:00
+            isLightActive = (nowMinutes >= lightMinutes || nowMinutes < darkMinutes);
+        }
+
+        if (isLightActive)
+        {
+            if (settings.changeSystem)
+                SetSystemTheme(true);
+            if (settings.changeApps)
+                SetAppsTheme(true);
+        }
+        else
+        {
+            if (settings.changeSystem)
+                SetSystemTheme(false);
+            if (settings.changeApps)
+                SetAppsTheme(false);
+        }
+    };
+
+    // --- At service start: immediately honor the schedule ---
+    {
+        SYSTEMTIME st;
+        GetLocalTime(&st);
+        int nowMinutes = st.wHour * 60 + st.wMinute;
+
+        LightSwitchSettings::instance().LoadSettings();
+        const auto& settings = LightSwitchSettings::instance().settings();
+
+        applyTheme(nowMinutes, settings.lightTime + settings.offset, settings.darkTime + settings.offset, settings);
+    }
+
+    // --- Main loop: wakes once per minute or stop/parent death ---
+    for (;;)
+    {
+        HANDLE waits[2] = { g_ServiceStopEvent, hParent };
+        DWORD count = hParent ? 2 : 1;
+
+        SYSTEMTIME st;
+        GetLocalTime(&st);
+        int nowMinutes = st.wHour * 60 + st.wMinute;
+
+        LightSwitchSettings::instance().LoadSettings();
+        const auto& settings = LightSwitchSettings::instance().settings();
+
+        // Debug print
+        wchar_t msg[160];
+        swprintf_s(msg,
+                   L"[LightSwitchService] now=%02d:%02d | light=%02d:%02d | dark=%02d:%02d\n",
+                   st.wHour,
+                   st.wMinute,
+                   settings.lightTime / 60,
+                   settings.lightTime % 60,
+                   settings.darkTime / 60,
+                   settings.darkTime % 60);
+        OutputDebugString(msg);
+
+        // Apply theme logic
+        applyTheme(nowMinutes, settings.lightTime + settings.offset, settings.darkTime + settings.offset, settings);
+
+        // Sleep until next minute, wake early if stop/parent dies
+        GetLocalTime(&st);
+        int msToNextMinute = (60 - st.wSecond) * 1000 - st.wMilliseconds;
+        if (msToNextMinute < 50)
+            msToNextMinute = 50;
+
+        DWORD wait = WaitForMultipleObjects(count, waits, FALSE, msToNextMinute);
+        if (wait == WAIT_OBJECT_0) // stop event
+            break;
+        if (hParent && wait == WAIT_OBJECT_0 + 1) // parent exited
+            break;
+    }
+
+    if (hParent)
+        CloseHandle(hParent);
+
+    return 0;
+}
+
+int APIENTRY wWinMain(HINSTANCE, HINSTANCE, PWSTR, int)
+{
+    if (powertoys_gpo::getConfiguredLightSwitchEnabledValue() == powertoys_gpo::gpo_rule_configured_disabled)
+    {
+        wchar_t msg[160];
+        swprintf_s(
+            msg,
+            L"Tried to start with a GPO policy setting the utility to always be disabled. Please contact your systems administrator.\n");
+        OutputDebugString(msg);
+        return 0;
+    }
+
+    int argc = 0;
+    LPWSTR* argv = CommandLineToArgvW(GetCommandLineW(), &argc);
+    int rc = _tmain(argc, argv); // reuse your existing logic
+    LocalFree(argv);
+    return rc;
+}

src/modules/LightSwitch/LightSwitchService/LightSwitchService.vcxproj

@@ -0,0 +1,254 @@
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src/modules/LightSwitch/LightSwitchService/LightSwitchService.vcxproj.filters

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+      <Filter>Source Files</Filter>
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+      <Filter>Header Files</Filter>
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+    <ClInclude Include="SettingsConstants.h">
+      <Filter>Header Files</Filter>
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src/modules/LightSwitch/LightSwitchService/LightSwitchSettings.cpp

@@ -0,0 +1,148 @@
+#include "LightSwitchSettings.h"
+#include <common/utils/json.h>
+#include <common/SettingsAPI/settings_helpers.h>
+#include "SettingsObserver.h"
+
+#include <filesystem>
+#include <fstream>
+#include <WinHookEventIDs.h>
+
+using namespace std;
+
+LightSwitchSettings& LightSwitchSettings::instance()
+{
+    static LightSwitchSettings inst;
+    return inst;
+}
+
+LightSwitchSettings::LightSwitchSettings()
+{
+    LoadSettings();
+}
+
+std::wstring LightSwitchSettings::GetSettingsFileName()
+{
+    // Mirrors AlwaysOnTop: <module name>.json
+    return PTSettingsHelper::get_module_save_file_location(L"LightSwitch");
+}
+
+void LightSwitchSettings::InitFileWatcher()
+{
+    const std::wstring& settingsFileName = GetSettingsFileName();
+    m_settingsFileWatcher = std::make_unique<FileWatcher>(settingsFileName, [&]() {
+        PostMessageW(HWND_BROADCAST, WM_PRIV_SETTINGS_CHANGED, NULL, NULL);
+    });
+}
+
+void LightSwitchSettings::AddObserver(SettingsObserver& observer)
+{
+    m_observers.insert(&observer);
+}
+
+void LightSwitchSettings::RemoveObserver(SettingsObserver& observer)
+{
+    m_observers.erase(&observer);
+}
+
+void LightSwitchSettings::NotifyObservers(SettingId id) const
+{
+    for (auto observer : m_observers)
+    {
+        if (observer->WantsToBeNotified(id))
+        {
+            observer->SettingsUpdate(id);
+        }
+    }
+}
+
+void LightSwitchSettings::LoadSettings()
+{
+    try
+    {
+        PowerToysSettings::PowerToyValues values =
+            PowerToysSettings::PowerToyValues::load_from_settings_file(L"LightSwitch");
+
+
+        if (const auto jsonVal = values.get_string_value(L"scheduleMode"))
+        {
+            auto val = *jsonVal;
+            auto newMode = FromString(val);
+            if (m_settings.scheduleMode != newMode)
+            {
+                m_settings.scheduleMode = newMode;
+                NotifyObservers(SettingId::ScheduleMode);
+            }
+        }
+
+        // Latitude
+        if (const auto jsonVal = values.get_string_value(L"latitude"))
+        {
+            auto val = *jsonVal;
+            if (m_settings.latitude != val)
+            {
+                m_settings.latitude = val;
+                NotifyObservers(SettingId::Latitude);
+            }
+        }
+
+        // Longitude
+        if (const auto jsonVal = values.get_string_value(L"longitude"))
+        {
+            auto val = *jsonVal;
+            if (m_settings.longitude != val)
+            {
+                m_settings.longitude = val;
+                NotifyObservers(SettingId::Longitude);
+            }
+        }
+
+        // LightTime
+        if (const auto jsonVal = values.get_int_value(L"lightTime"))
+        {
+            auto val = *jsonVal;
+            if (m_settings.lightTime != val)
+            {
+                m_settings.lightTime = val;
+                NotifyObservers(SettingId::LightTime);
+            }
+        }
+
+        // DarkTime
+        if (const auto jsonVal = values.get_int_value(L"darkTime"))
+        {
+            auto val = *jsonVal;
+            if (m_settings.darkTime != val)
+            {
+                m_settings.darkTime = val;
+                NotifyObservers(SettingId::DarkTime);
+            }
+        }
+
+        // ChangeSystem
+        if (const auto jsonVal = values.get_bool_value(L"changeSystem"))
+        {
+            auto val = *jsonVal;
+            if (m_settings.changeSystem != val)
+            {
+                m_settings.changeSystem = val;
+                NotifyObservers(SettingId::ChangeSystem);
+            }
+        }
+
+        // ChangeApps
+        if (const auto jsonVal = values.get_bool_value(L"changeApps"))
+        {
+            auto val = *jsonVal;
+            if (m_settings.changeApps != val)
+            {
+                m_settings.changeApps = val;
+                NotifyObservers(SettingId::ChangeApps);
+            }
+        }
+    }
+    catch (...)
+    {
+        //Logger::error(L"[LightSwitchSettings] Failed to read settings file");
+        // Keeps defaults if load fails
+    }
+}

src/modules/LightSwitch/LightSwitchService/LightSwitchSettings.h

@@ -0,0 +1,87 @@
+#pragma once
+
+#include <unordered_set>
+#include <string>
+#include <vector>
+#include <memory>
+#include <windows.h>
+
+#include <common/SettingsAPI/FileWatcher.h>
+#include <common/SettingsAPI/settings_objects.h>
+#include <SettingsConstants.h>
+
+class SettingsObserver;
+
+enum class ScheduleMode
+{
+    FixedHours,
+    SunsetToSunrise
+    // Add more in the future
+};
+
+inline std::wstring ToString(ScheduleMode mode)
+{
+    switch (mode)
+    {
+    case ScheduleMode::FixedHours:
+        return L"FixedHours";
+    case ScheduleMode::SunsetToSunrise:
+        return L"SunsetToSunrise";
+    default:
+        return L"FixedHours";
+    }
+}
+
+inline ScheduleMode FromString(const std::wstring& str)
+{
+    if (str == L"SunsetToSunrise")
+        return ScheduleMode::SunsetToSunrise;
+    else
+        return ScheduleMode::FixedHours;
+}
+
+struct LightSwitchConfig
+{
+    ScheduleMode scheduleMode = ScheduleMode::FixedHours;
+
+    std::wstring latitude = L"0.0";
+    std::wstring longitude = L"0.0";
+
+    // Stored as minutes since midnight
+    int lightTime = 8 * 60; // 08:00 default
+    int darkTime = 20 * 60; // 20:00 default
+
+    int offset = 0; // offset in minutes to apply to calculated times
+
+    bool changeSystem = false;
+    bool changeApps = false;
+};
+
+class LightSwitchSettings
+{
+public:
+    static LightSwitchSettings& instance();
+
+    static inline const LightSwitchConfig& settings()
+    {
+        return instance().m_settings;
+    }
+
+    void InitFileWatcher();
+    static std::wstring GetSettingsFileName();
+
+    void AddObserver(SettingsObserver& observer);
+    void RemoveObserver(SettingsObserver& observer);
+
+    void LoadSettings();
+
+private:
+    LightSwitchSettings();
+    ~LightSwitchSettings() = default;
+
+    LightSwitchConfig m_settings;
+    std::unique_ptr<FileWatcher> m_settingsFileWatcher;
+    std::unordered_set<SettingsObserver*> m_observers;
+
+    void NotifyObservers(SettingId id) const;
+};

src/modules/LightSwitch/LightSwitchService/SettingsConstants.cpp

@@ -0,0 +1 @@
+#include "SettingsConstants.h"

src/modules/LightSwitch/LightSwitchService/SettingsConstants.h

@@ -0,0 +1,12 @@
+#pragma once
+
+enum class SettingId
+{
+    ScheduleMode = 0,
+    Latitude,
+    Longitude,
+    LightTime,
+    DarkTime,
+    ChangeSystem,
+    ChangeApps
+};

src/modules/LightSwitch/LightSwitchService/SettingsObserver.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include <unordered_set>
+#include "SettingsConstants.h"
+
+class LightSwitchSettings;
+
+class SettingsObserver
+{
+public:
+    SettingsObserver(std::unordered_set<SettingId> observedSettings) :
+        m_observedSettings(std::move(observedSettings))
+    {
+        LightSwitchSettings::instance().AddObserver(*this);
+    }
+
+    virtual ~SettingsObserver()
+    {
+        LightSwitchSettings::instance().RemoveObserver(*this);
+    }
+
+    // Override this in your class to respond to updates
+    virtual void SettingsUpdate(SettingId type) {}
+
+    bool WantsToBeNotified(SettingId type) const noexcept
+    {
+        return m_observedSettings.contains(type);
+    }
+
+protected:
+    std::unordered_set<SettingId> m_observedSettings;
+};

src/modules/LightSwitch/LightSwitchService/ThemeHelper.cpp

@@ -0,0 +1,80 @@
+#include <windows.h>
+#include "ThemeHelper.h"
+
+// Controls changing the themes.
+
+void SetAppsTheme(bool mode)
+{
+    HKEY hKey;
+    if (RegOpenKeyEx(HKEY_CURRENT_USER,
+                     L"Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize",
+                     0,
+                     KEY_SET_VALUE,
+                     &hKey) == ERROR_SUCCESS)
+    {
+        DWORD value = mode;
+        RegSetValueEx(hKey, L"AppsUseLightTheme", 0, REG_DWORD, reinterpret_cast<const BYTE*>(&value), sizeof(value));
+        RegCloseKey(hKey);
+
+        SendMessageTimeout(HWND_BROADCAST, WM_SETTINGCHANGE, 0, reinterpret_cast<LPARAM>(L"ImmersiveColorSet"), SMTO_ABORTIFHUNG, 5000, nullptr);
+
+        SendMessageTimeout(HWND_BROADCAST, WM_THEMECHANGED, 0, 0, SMTO_ABORTIFHUNG, 5000, nullptr);
+    }
+}
+
+void SetSystemTheme(bool mode)
+{
+    HKEY hKey;
+    if (RegOpenKeyEx(HKEY_CURRENT_USER,
+                     L"Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize",
+                     0,
+                     KEY_SET_VALUE,
+                     &hKey) == ERROR_SUCCESS)
+    {
+        DWORD value = mode;
+        RegSetValueEx(hKey, L"SystemUsesLightTheme", 0, REG_DWORD, reinterpret_cast<const BYTE*>(&value), sizeof(value));
+        RegCloseKey(hKey);
+
+        SendMessageTimeout(HWND_BROADCAST, WM_SETTINGCHANGE, 0, reinterpret_cast<LPARAM>(L"ImmersiveColorSet"), SMTO_ABORTIFHUNG, 5000, nullptr);
+
+        SendMessageTimeout(HWND_BROADCAST, WM_THEMECHANGED, 0, 0, SMTO_ABORTIFHUNG, 5000, nullptr);
+    }
+}
+
+bool GetCurrentSystemTheme()
+{
+    HKEY hKey;
+    DWORD value = 1; // default = light
+    DWORD size = sizeof(value);
+
+    if (RegOpenKeyEx(HKEY_CURRENT_USER,
+                     L"Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize",
+                     0,
+                     KEY_READ,
+                     &hKey) == ERROR_SUCCESS)
+    {
+        RegQueryValueEx(hKey, L"SystemUsesLightTheme", nullptr, nullptr, reinterpret_cast<LPBYTE>(&value), &size);
+        RegCloseKey(hKey);
+    }
+
+    return value == 0; // 0 = dark, 1 = light
+}
+
+bool GetCurrentAppsTheme()
+{
+    HKEY hKey;
+    DWORD value = 1;
+    DWORD size = sizeof(value);
+
+    if (RegOpenKeyEx(HKEY_CURRENT_USER,
+                     L"Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize",
+                     0,
+                     KEY_READ,
+                     &hKey) == ERROR_SUCCESS)
+    {
+        RegQueryValueEx(hKey, L"SystemUsesLightTheme", nullptr, nullptr, reinterpret_cast<LPBYTE>(&value), &size);
+        RegCloseKey(hKey);
+    }
+
+    return value == 0;
+}

src/modules/LightSwitch/LightSwitchService/ThemeHelper.h

@@ -0,0 +1,5 @@
+#pragma once
+void SetSystemTheme(bool dark);
+void SetAppsTheme(bool dark);
+bool GetCurrentSystemTheme();
+bool GetCurrentAppsTheme();

src/modules/LightSwitch/LightSwitchService/ThemeScheduler.cpp

@@ -0,0 +1,89 @@
+#include "ThemeScheduler.h"
+#include <utility>
+
+SunTimes CalculateSunriseSunset(double latitude, double longitude, int year, int month, int day)
+{
+    double zenith = 90.833;
+    int N1 = static_cast<int>(floor(275.0 * month / 9.0));
+    int N2 = static_cast<int>(floor((static_cast<double>(month) + 9) / 12.0));
+    int N3 = static_cast<int>(floor((1.0 + floor((year - 4.0 * floor(year / 4.0) + 2.0) / 3.0))));
+    int N = N1 - (N2 * N3) + day - 30;
+
+    auto calcTime = [&](bool sunrise) -> double {
+        double lngHour = longitude / 15.0;
+        double t = sunrise ? N + ((6 - lngHour) / 24) : N + ((18 - lngHour) / 24);
+
+        double M = (0.9856 * t) - 3.289;
+        double L = M + (1.916 * sin(deg2rad(M))) + (0.020 * sin(2 * deg2rad(M))) + 282.634;
+        if (L < 0)
+            L += 360;
+        if (L > 360)
+            L -= 360;
+
+        double RA = rad2deg(atan(0.91764 * tan(deg2rad(L))));
+        if (RA < 0)
+            RA += 360;
+        if (RA > 360)
+            RA -= 360;
+
+        double Lquadrant = floor(L / 90) * 90;
+        double RAquadrant = floor(RA / 90) * 90;
+        RA = RA + (Lquadrant - RAquadrant);
+        RA /= 15;
+
+        double sinDec = 0.39782 * sin(deg2rad(L));
+        double cosDec = cos(asin(sinDec));
+
+        double cosH = (cos(deg2rad(zenith)) - (sinDec * sin(deg2rad(latitude)))) / (cosDec * cos(deg2rad(latitude)));
+        if (cosH > 1 || cosH < -1)
+            return -1;
+
+        double H = sunrise ? 360 - rad2deg(acos(cosH)) : rad2deg(acos(cosH));
+        H /= 15;
+
+        double T = H + RA - (0.06571 * t) - 6.622;
+        double UT = T - lngHour;
+        while (UT < 0)
+            UT += 24;
+        while (UT >= 24)
+            UT -= 24;
+
+        return UT;
+    };
+
+    double riseUT = calcTime(true);
+    double setUT = calcTime(false);
+
+    auto toLocal = [](double UT) {
+        TIME_ZONE_INFORMATION tz;
+        DWORD state = GetTimeZoneInformation(&tz);
+        double totalBias = tz.Bias;
+
+        if (state == TIME_ZONE_ID_DAYLIGHT)
+            totalBias += tz.DaylightBias;
+        else if (state == TIME_ZONE_ID_STANDARD)
+            totalBias += tz.StandardBias;
+
+        double biasHours = -(totalBias / 60.0);
+        double localTime = UT + biasHours;
+
+        while (localTime < 0)
+            localTime += 24;
+        while (localTime >= 24)
+            localTime -= 24;
+
+        int hour = static_cast<int>(localTime);
+        int minute = static_cast<int>((localTime - hour) * 60);
+        return std::pair<int, int>{ hour, minute };
+    };
+
+    auto [riseHour, riseMinute] = toLocal(riseUT);
+    auto [setHour, setMinute] = toLocal(setUT);
+
+    SunTimes result;
+    result.sunriseHour = riseHour;
+    result.sunriseMinute = riseMinute;
+    result.sunsetHour = setHour;
+    result.sunsetMinute = setMinute;
+    return result;
+}

src/modules/LightSwitch/LightSwitchService/ThemeScheduler.h

@@ -0,0 +1,25 @@
+#pragma once
+#include <cmath>
+#include <ctime>
+#include <windows.h>
+
+// Struct to hold calculated sunrise/sunset times
+struct SunTimes
+{
+    int sunriseHour;
+    int sunriseMinute;
+    int sunsetHour;
+    int sunsetMinute;
+};
+
+constexpr double PI = 3.14159265358979323846;
+constexpr double deg2rad(double deg)
+{
+    return deg * PI / 180.0;
+}
+constexpr double rad2deg(double rad)
+{
+    return rad * 180.0 / PI;
+}
+
+SunTimes CalculateSunriseSunset(double latitude, double longitude, int year, int month, int day);

src/modules/LightSwitch/LightSwitchService/WinHookEventIDs.cpp

@@ -0,0 +1,15 @@
+
+#include "WinHookEventIDs.h"
+#include <wtypes.h>
+#include <mutex>
+
+UINT WM_PRIV_SETTINGS_CHANGED = 0;
+
+std::once_flag init_flag;
+
+void InitializeWinhookEventIds()
+{
+    std::call_once(init_flag, [&] {
+        WM_PRIV_SETTINGS_CHANGED = RegisterWindowMessage(L"{11978F7B-221A-4E65-B9A9-693F7D6E4B25}");
+    });
+}

src/modules/LightSwitch/LightSwitchService/WinHookEventIDs.h

@@ -0,0 +1,6 @@
+#pragma once
+#include <Windows.h>
+
+extern UINT WM_PRIV_SETTINGS_CHANGED; // Scheduled when a watched settings file is updated
+
+void InitializeWinhookEventIds();

src/modules/LightSwitch/LightSwitchService/packages.config

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="Microsoft.Windows.CppWinRT" version="2.0.240111.5" targetFramework="native" />
+  <package id="Microsoft.Windows.ImplementationLibrary" version="1.0.231216.1" targetFramework="native" />
+</packages>

src/modules/cmdpal/Microsoft.CmdPal.Common/Helpers/DiagnosticsHelper.cs

@@ -0,0 +1,66 @@
+// 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.Runtime.InteropServices;
+
+namespace Microsoft.CmdPal.Common.Helpers;
+
+/// <summary>
+/// Provides utility methods for building diagnostic and error messages.
+/// </summary>
+public static class DiagnosticsHelper
+{
+    /// <summary>
+    /// Builds a comprehensive exception message with timestamp and detailed diagnostic information.
+    /// </summary>
+    /// <param name="exception">The exception that occurred.</param>
+    /// <param name="extensionHint">A hint about which extension caused the exception to help with debugging.</param>
+    /// <returns>A string containing the exception details, timestamp, and source information for diagnostic purposes.</returns>
+    public static string BuildExceptionMessage(Exception exception, string? extensionHint)
+    {
+        var locationHint = string.IsNullOrWhiteSpace(extensionHint) ? "application" : $"'{extensionHint}' extension";
+
+        // let's try to get a message from the exception or inferred it from the HRESULT
+        // to show at least something
+        var message = exception.Message;
+        if (string.IsNullOrWhiteSpace(message))
+        {
+            var temp = Marshal.GetExceptionForHR(exception.HResult)?.Message;
+            if (!string.IsNullOrWhiteSpace(temp))
+            {
+                message = temp + $" (inferred from HRESULT 0x{exception.HResult:X8})";
+            }
+        }
+
+        if (string.IsNullOrWhiteSpace(message))
+        {
+            message = "[No message available]";
+        }
+
+        // note: keep date time kind and format consistent with the log
+        return $"""
+                ============================================================
+                😢 An unexpected error occurred in the {locationHint}.
+
+                Summary:
+                  Message:    {message}
+                  Type:       {exception.GetType().FullName}
+                  Source:     {exception.Source ?? "N/A"}
+                  Time:       {DateTimeOffset.Now:yyyy-MM-dd HH:mm:ss.fffffff}
+                  HRESULT:    0x{exception.HResult:X8} ({exception.HResult})
+
+                Stack Trace:
+                {exception.StackTrace ?? "[No stack trace available]"}
+
+                ------------------ Full Exception Details ------------------
+                {exception}
+
+                ℹ️ If you need further assistance, please include this information in your support request.
+                ℹ️ Before sending, take a quick look to make sure it doesn't contain any personal or sensitive information.
+                ============================================================
+
+                """;
+    }
+}

src/modules/cmdpal/Microsoft.CmdPal.Common/Helpers/ExtensionHostInstance.cs

@@ -24,7 +24,7 @@ public partial class ExtensionHostInstance
     /// <param name="message">The log message to send</param>
     public void LogMessage(ILogMessage message)
     {
-        if (Host != null)
+        if (Host is not null)
         {
             _ = Task.Run(async () =>
             {
@@ -47,7 +47,7 @@ public partial class ExtensionHostInstance
 
     public void ShowStatus(IStatusMessage message, StatusContext context)
     {
-        if (Host != null)
+        if (Host is not null)
         {
             _ = Task.Run(async () =>
             {
@@ -64,7 +64,7 @@ public partial class ExtensionHostInstance
 
     public void HideStatus(IStatusMessage message)
     {
-        if (Host != null)
+        if (Host is not null)
         {
             _ = Task.Run(async () =>
             {

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/AppExtensionHost.cs

@@ -36,7 +36,7 @@ public abstract partial class AppExtensionHost : IExtensionHost
 
     public IAsyncAction HideStatus(IStatusMessage? message)
     {
-        if (message == null)
+        if (message is null)
         {
             return Task.CompletedTask.AsAsyncAction();
         }
@@ -55,7 +55,7 @@ public abstract partial class AppExtensionHost : IExtensionHost
 
     public IAsyncAction LogMessage(ILogMessage? message)
     {
-        if (message == null)
+        if (message is null)
         {
             return Task.CompletedTask.AsAsyncAction();
         }
@@ -80,7 +80,7 @@ public abstract partial class AppExtensionHost : IExtensionHost
                 try
                 {
                     var vm = StatusMessages.Where(messageVM => messageVM.Model.Unsafe == message).FirstOrDefault();
-                    if (vm != null)
+                    if (vm is not null)
                     {
                         StatusMessages.Remove(vm);
                     }
@@ -113,7 +113,7 @@ public abstract partial class AppExtensionHost : IExtensionHost
     {
         // If this message is already in the list of messages, just bring it to the top
         var oldVm = StatusMessages.Where(messageVM => messageVM.Model.Unsafe == message).FirstOrDefault();
-        if (oldVm != null)
+        if (oldVm is not null)
         {
             Task.Factory.StartNew(
                 () =>
@@ -142,7 +142,7 @@ public abstract partial class AppExtensionHost : IExtensionHost
 
     public IAsyncAction ShowStatus(IStatusMessage? message, StatusContext context)
     {
-        if (message == null)
+        if (message is null)
         {
             return Task.CompletedTask.AsAsyncAction();
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/CommandBarViewModel.cs

@@ -2,7 +2,6 @@
 // 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.Collections.ObjectModel;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Messaging;
 using Microsoft.CmdPal.Core.ViewModels.Messages;
@@ -35,13 +34,13 @@ public partial class CommandBarViewModel : ObservableObject,
     [NotifyPropertyChangedFor(nameof(HasPrimaryCommand))]
     public partial CommandItemViewModel? PrimaryCommand { get; set; }
 
-    public bool HasPrimaryCommand => PrimaryCommand != null && PrimaryCommand.ShouldBeVisible;
+    public bool HasPrimaryCommand => PrimaryCommand is not null && PrimaryCommand.ShouldBeVisible;
 
     [ObservableProperty]
     [NotifyPropertyChangedFor(nameof(HasSecondaryCommand))]
     public partial CommandItemViewModel? SecondaryCommand { get; set; }
 
-    public bool HasSecondaryCommand => SecondaryCommand != null;
+    public bool HasSecondaryCommand => SecondaryCommand is not null;
 
     [ObservableProperty]
     public partial bool ShouldShowContextMenu { get; set; } = false;
@@ -58,14 +57,14 @@ public partial class CommandBarViewModel : ObservableObject,
 
     private void SetSelectedItem(ICommandBarContext? value)
     {
-        if (value != null)
+        if (value is not null)
         {
             PrimaryCommand = value.PrimaryCommand;
             value.PropertyChanged += SelectedItemPropertyChanged;
         }
         else
         {
-            if (SelectedItem != null)
+            if (SelectedItem is not null)
             {
                 SelectedItem.PropertyChanged -= SelectedItemPropertyChanged;
             }
@@ -88,7 +87,7 @@ public partial class CommandBarViewModel : ObservableObject,
 
     private void UpdateContextItems()
     {
-        if (SelectedItem == null)
+        if (SelectedItem is null)
         {
             SecondaryCommand = null;
             ShouldShowContextMenu = false;
@@ -127,13 +126,13 @@ public partial class CommandBarViewModel : ObservableObject,
     public ContextKeybindingResult CheckKeybinding(bool ctrl, bool alt, bool shift, bool win, VirtualKey key)
     {
         var keybindings = SelectedItem?.Keybindings();
-        if (keybindings != null)
+        if (keybindings is not null)
         {
             // Does the pressed key match any of the keybindings?
             var pressedKeyChord = KeyChordHelpers.FromModifiers(ctrl, alt, shift, win, key, 0);
             if (keybindings.TryGetValue(pressedKeyChord, out var matchedItem))
             {
-                return matchedItem != null ? PerformCommand(matchedItem) : ContextKeybindingResult.Unhandled;
+                return matchedItem is not null ? PerformCommand(matchedItem) : ContextKeybindingResult.Unhandled;
             }
         }
 
@@ -142,7 +141,7 @@ public partial class CommandBarViewModel : ObservableObject,
 
     private ContextKeybindingResult PerformCommand(CommandItemViewModel? command)
     {
-        if (command == null)
+        if (command is null)
         {
             return ContextKeybindingResult.Unhandled;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/CommandContextItemViewModel.cs

@@ -20,7 +20,7 @@ public partial class CommandContextItemViewModel(ICommandContextItem contextItem
 
     public KeyChord? RequestedShortcut { get; private set; }
 
-    public bool HasRequestedShortcut => RequestedShortcut != null && (RequestedShortcut.Value != nullKeyChord);
+    public bool HasRequestedShortcut => RequestedShortcut is not null && (RequestedShortcut.Value != nullKeyChord);
 
     public override void InitializeProperties()
     {
@@ -32,7 +32,7 @@ public partial class CommandContextItemViewModel(ICommandContextItem contextItem
         base.InitializeProperties();
 
         var contextItem = Model.Unsafe;
-        if (contextItem == null)
+        if (contextItem is null)
         {
             return; // throw?
         }

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

@@ -68,7 +68,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
     {
         get
         {
-            List<IContextItemViewModel> l = _defaultCommandContextItem == null ?
+            List<IContextItemViewModel> l = _defaultCommandContextItem is null ?
                 new() :
                 [_defaultCommandContextItem];
 
@@ -100,7 +100,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
         }
 
         var model = _commandItemModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
@@ -128,7 +128,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
         }
 
         var model = _commandItemModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
@@ -136,7 +136,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
         Command.InitializeProperties();
 
         var listIcon = model.Icon;
-        if (listIcon != null)
+        if (listIcon is not null)
         {
             _listItemIcon = new(listIcon);
             _listItemIcon.InitializeProperties();
@@ -172,13 +172,13 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
         }
 
         var model = _commandItemModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
 
         var more = model.MoreCommands;
-        if (more != null)
+        if (more is not null)
         {
             MoreCommands = more
                 .Select(item =>
@@ -300,7 +300,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
     protected virtual void FetchProperty(string propertyName)
     {
         var model = this._commandItemModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -308,7 +308,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
         switch (propertyName)
         {
             case nameof(Command):
-                if (Command != null)
+                if (Command is not null)
                 {
                     Command.PropertyChanged -= Command_PropertyChanged;
                 }
@@ -339,7 +339,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
 
             case nameof(model.MoreCommands):
                 var more = model.MoreCommands;
-                if (more != null)
+                if (more is not null)
                 {
                     var newContextMenu = more
                         .Select(item =>
@@ -394,7 +394,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
                 // Extensions based on Command Palette SDK < 0.3 CommandItem class won't notify when Title changes because Command
                 // or Command.Name change. This is a workaround to ensure that the Title is always up-to-date for extensions with old SDK.
                 var model = _commandItemModel.Unsafe;
-                if (model != null)
+                if (model is not null)
                 {
                     _itemTitle = model.Title;
                 }
@@ -430,7 +430,7 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
         Command.SafeCleanup();
 
         var model = _commandItemModel.Unsafe;
-        if (model != null)
+        if (model is not null)
         {
             model.PropChanged -= Model_PropChanged;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/CommandViewModel.cs

@@ -44,7 +44,7 @@ public partial class CommandViewModel : ExtensionObjectViewModel
         }
 
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
@@ -67,13 +67,13 @@ public partial class CommandViewModel : ExtensionObjectViewModel
         }
 
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
 
         var ico = model.Icon;
-        if (ico != null)
+        if (ico is not null)
         {
             Icon = new(ico);
             Icon.InitializeProperties();
@@ -98,7 +98,7 @@ public partial class CommandViewModel : ExtensionObjectViewModel
     protected void FetchProperty(string propertyName)
     {
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -125,7 +125,7 @@ public partial class CommandViewModel : ExtensionObjectViewModel
         Icon = new(null); // necessary?
 
         var model = Model.Unsafe;
-        if (model != null)
+        if (model is not null)
         {
             model.PropChanged -= Model_PropChanged;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/ConfirmResultViewModel.cs

@@ -25,7 +25,7 @@ public partial class ConfirmResultViewModel(IConfirmationArgs _args, WeakReferen
     public override void InitializeProperties()
     {
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/ContentPageViewModel.cs

@@ -28,7 +28,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
     public DetailsViewModel? Details { get; private set; }
 
     [MemberNotNullWhen(true, nameof(Details))]
-    public bool HasDetails => Details != null;
+    public bool HasDetails => Details is not null;
 
     /////// ICommandBarContext ///////
     public IEnumerable<IContextItemViewModel> MoreCommands => Commands.Skip(1);
@@ -67,7 +67,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
             foreach (var item in newItems)
             {
                 var viewModel = ViewModelFromContent(item, PageContext);
-                if (viewModel != null)
+                if (viewModel is not null)
                 {
                     viewModel.InitializeProperties();
                     newContent.Add(viewModel);
@@ -104,7 +104,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
         base.InitializeProperties();
 
         var model = _model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -133,7 +133,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
             });
 
         var extensionDetails = model.Details;
-        if (extensionDetails != null)
+        if (extensionDetails is not null)
         {
             Details = new(extensionDetails, PageContext);
             Details.InitializeProperties();
@@ -156,7 +156,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
         base.FetchProperty(propertyName);
 
         var model = this._model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -166,7 +166,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
             case nameof(Commands):
 
                 var more = model.Commands;
-                if (more != null)
+                if (more is not null)
                 {
                     var newContextMenu = more
                             .ToList()
@@ -216,7 +216,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
                 break;
             case nameof(Details):
                 var extensionDetails = model.Details;
-                Details = extensionDetails != null ? new(extensionDetails, PageContext) : null;
+                Details = extensionDetails is not null ? new(extensionDetails, PageContext) : null;
                 UpdateDetails();
                 break;
         }
@@ -248,7 +248,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
     [RelayCommand]
     private void InvokePrimaryCommand(ContentPageViewModel page)
     {
-        if (PrimaryCommand != null)
+        if (PrimaryCommand is not null)
         {
             WeakReferenceMessenger.Default.Send<PerformCommandMessage>(new(PrimaryCommand.Command.Model, PrimaryCommand.Model));
         }
@@ -258,7 +258,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
     [RelayCommand]
     private void InvokeSecondaryCommand(ContentPageViewModel page)
     {
-        if (SecondaryCommand != null)
+        if (SecondaryCommand is not null)
         {
             WeakReferenceMessenger.Default.Send<PerformCommandMessage>(new(SecondaryCommand.Command.Model, SecondaryCommand.Model));
         }
@@ -285,7 +285,7 @@ public abstract partial class ContentPageViewModel : PageViewModel, ICommandBarC
         Content.Clear();
 
         var model = _model.Unsafe;
-        if (model != null)
+        if (model is not null)
         {
             model.ItemsChanged -= Model_ItemsChanged;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/ContextMenuViewModel.cs

@@ -8,7 +8,6 @@ using CommunityToolkit.Mvvm.Messaging;
 using Microsoft.CmdPal.Core.ViewModels.Messages;
 using Microsoft.CommandPalette.Extensions;
 using Microsoft.CommandPalette.Extensions.Toolkit;
-using Microsoft.Diagnostics.Utilities;
 using Windows.System;
 
 namespace Microsoft.CmdPal.Core.ViewModels;
@@ -51,7 +50,7 @@ public partial class ContextMenuViewModel : ObservableObject,
 
     public void UpdateContextItems()
     {
-        if (SelectedItem != null)
+        if (SelectedItem is not null)
         {
             if (SelectedItem.MoreCommands.Count() > 1)
             {
@@ -68,14 +67,14 @@ public partial class ContextMenuViewModel : ObservableObject,
             return;
         }
 
-        if (SelectedItem == null)
+        if (SelectedItem is null)
         {
             return;
         }
 
         _lastSearchText = searchText;
 
-        if (CurrentContextMenu == null)
+        if (CurrentContextMenu is null)
         {
             ListHelpers.InPlaceUpdateList(FilteredItems, []);
             return;
@@ -124,7 +123,7 @@ public partial class ContextMenuViewModel : ObservableObject,
     /// that have a shortcut key set.</returns>
     public Dictionary<KeyChord, CommandContextItemViewModel> Keybindings()
     {
-        if (CurrentContextMenu == null)
+        if (CurrentContextMenu is null)
         {
             return [];
         }
@@ -140,7 +139,7 @@ public partial class ContextMenuViewModel : ObservableObject,
     public ContextKeybindingResult? CheckKeybinding(bool ctrl, bool alt, bool shift, bool win, VirtualKey key)
     {
         var keybindings = Keybindings();
-        if (keybindings != null)
+        if (keybindings is not null)
         {
             // Does the pressed key match any of the keybindings?
             var pressedKeyChord = KeyChordHelpers.FromModifiers(ctrl, alt, shift, win, key, 0);
@@ -190,7 +189,7 @@ public partial class ContextMenuViewModel : ObservableObject,
         OnPropertyChanging(nameof(CurrentContextMenu));
         OnPropertyChanged(nameof(CurrentContextMenu));
 
-        if (CurrentContextMenu != null)
+        if (CurrentContextMenu is not null)
         {
             ListHelpers.InPlaceUpdateList(FilteredItems, [.. CurrentContextMenu!]);
         }
@@ -198,7 +197,7 @@ public partial class ContextMenuViewModel : ObservableObject,
 
     public ContextKeybindingResult InvokeCommand(CommandItemViewModel? command)
     {
-        if (command == null)
+        if (command is null)
         {
             return ContextKeybindingResult.Unhandled;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/DetailsCommandsViewModel.cs

@@ -22,7 +22,7 @@ public partial class DetailsCommandsViewModel(
     {
         base.InitializeProperties();
         var model = _dataModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/DetailsElementViewModel.cs

@@ -16,7 +16,7 @@ public abstract partial class DetailsElementViewModel(IDetailsElement _detailsEl
     public override void InitializeProperties()
     {
         var model = _model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/DetailsLinkViewModel.cs

@@ -18,7 +18,7 @@ public partial class DetailsLinkViewModel(
 
     public Uri? Link { get; private set; }
 
-    public bool IsLink => Link != null;
+    public bool IsLink => Link is not null;
 
     public bool IsText => !IsLink;
 
@@ -26,14 +26,14 @@ public partial class DetailsLinkViewModel(
     {
         base.InitializeProperties();
         var model = _dataModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
 
         Text = model.Text ?? string.Empty;
         Link = model.Link;
-        if (string.IsNullOrEmpty(Text) && Link != null)
+        if (string.IsNullOrEmpty(Text) && Link is not null)
         {
             Text = Link.ToString();
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/DetailsTagsViewModel.cs

@@ -22,7 +22,7 @@ public partial class DetailsTagsViewModel(
     {
         base.InitializeProperties();
         var model = _dataModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/DetailsViewModel.cs

@@ -26,7 +26,7 @@ public partial class DetailsViewModel(IDetails _details, WeakReference<IPageCont
     public override void InitializeProperties()
     {
         var model = _detailsModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
@@ -41,7 +41,7 @@ public partial class DetailsViewModel(IDetails _details, WeakReference<IPageCont
         UpdateProperty(nameof(HeroImage));
 
         var meta = model.Metadata;
-        if (meta != null)
+        if (meta is not null)
         {
             foreach (var element in meta)
             {
@@ -53,7 +53,7 @@ public partial class DetailsViewModel(IDetails _details, WeakReference<IPageCont
                     IDetailsTags => new DetailsTagsViewModel(element, this.PageContext),
                     _ => null,
                 };
-                if (vm != null)
+                if (vm is not null)
                 {
                     vm.InitializeProperties();
                     Metadata.Add(vm);

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/IconDataViewModel.cs

@@ -16,7 +16,7 @@ public partial class IconDataViewModel : ObservableObject, IIconData
     // If the extension previously gave us a Data, then died, the data will
     // throw if we actually try to read it, but the pointer itself won't be
     // null, so this is relatively safe.
-    public bool HasIcon => !string.IsNullOrEmpty(Icon) || Data.Unsafe != null;
+    public bool HasIcon => !string.IsNullOrEmpty(Icon) || Data.Unsafe is not null;
 
     // Locally cached properties from IIconData.
     public string Icon { get; private set; } = string.Empty;
@@ -36,7 +36,7 @@ public partial class IconDataViewModel : ObservableObject, IIconData
     public void InitializeProperties()
     {
         var model = _model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/IconInfoViewModel.cs

@@ -26,7 +26,7 @@ public partial class IconInfoViewModel : ObservableObject, IIconInfo
 
     public bool HasIcon(bool light) => IconForTheme(light).HasIcon;
 
-    public bool IsSet => _model.Unsafe != null;
+    public bool IsSet => _model.Unsafe is not null;
 
     IIconData? IIconInfo.Dark => Dark;
 
@@ -43,7 +43,7 @@ public partial class IconInfoViewModel : ObservableObject, IIconInfo
     public void InitializeProperties()
     {
         var model = _model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/ListItemViewModel.cs

@@ -27,7 +27,7 @@ public partial class ListItemViewModel(IListItem model, WeakReference<IPageConte
     public DetailsViewModel? Details { get; private set; }
 
     [MemberNotNullWhen(true, nameof(Details))]
-    public bool HasDetails => Details != null;
+    public bool HasDetails => Details is not null;
 
     public override void InitializeProperties()
     {
@@ -40,7 +40,7 @@ public partial class ListItemViewModel(IListItem model, WeakReference<IPageConte
         base.InitializeProperties();
 
         var li = Model.Unsafe;
-        if (li == null)
+        if (li is null)
         {
             return; // throw?
         }
@@ -50,7 +50,7 @@ public partial class ListItemViewModel(IListItem model, WeakReference<IPageConte
         TextToSuggest = li.TextToSuggest;
         Section = li.Section ?? string.Empty;
         var extensionDetails = li.Details;
-        if (extensionDetails != null)
+        if (extensionDetails is not null)
         {
             Details = new(extensionDetails, PageContext);
             Details.InitializeProperties();
@@ -67,7 +67,7 @@ public partial class ListItemViewModel(IListItem model, WeakReference<IPageConte
         base.FetchProperty(propertyName);
 
         var model = this.Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -85,7 +85,7 @@ public partial class ListItemViewModel(IListItem model, WeakReference<IPageConte
                 break;
             case nameof(Details):
                 var extensionDetails = model.Details;
-                Details = extensionDetails != null ? new(extensionDetails, PageContext) : null;
+                Details = extensionDetails is not null ? new(extensionDetails, PageContext) : null;
                 Details?.InitializeProperties();
                 UpdateProperty(nameof(Details));
                 UpdateProperty(nameof(HasDetails));
@@ -136,7 +136,7 @@ public partial class ListItemViewModel(IListItem model, WeakReference<IPageConte
         Details?.SafeCleanup();
 
         var model = Model.Unsafe;
-        if (model != null)
+        if (model is not null)
         {
             // We don't need to revoke the PropChanged event handler here,
             // because we are just overriding CommandItem's FetchProperty and

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

@@ -63,6 +63,7 @@ public partial class ListViewModel : PageViewModel, IDisposable
 
     private Task? _initializeItemsTask;
     private CancellationTokenSource? _cancellationTokenSource;
+    private CancellationTokenSource? _fetchItemsCancellationTokenSource;
 
     private ListItemViewModel? _lastSelectedItem;
 
@@ -129,14 +130,27 @@ public partial class ListViewModel : PageViewModel, IDisposable
     //// Run on background thread, from InitializeAsync or Model_ItemsChanged
     private void FetchItems()
     {
+        // Cancel any previous FetchItems operation
+        _fetchItemsCancellationTokenSource?.Cancel();
+        _fetchItemsCancellationTokenSource?.Dispose();
+        _fetchItemsCancellationTokenSource = new CancellationTokenSource();
+
+        var cancellationToken = _fetchItemsCancellationTokenSource.Token;
+
         // TEMPORARY: just plop all the items into a single group
         // see 9806fe5d8 for the last commit that had this with sections
         _isFetching = true;
 
         try
         {
+            // Check for cancellation before starting expensive operations
+            cancellationToken.ThrowIfCancellationRequested();
+
             var newItems = _model.Unsafe!.GetItems();
 
+            // Check for cancellation after getting items from extension
+            cancellationToken.ThrowIfCancellationRequested();
+
             // Collect all the items into new viewmodels
             Collection<ListItemViewModel> newViewModels = [];
 
@@ -145,6 +159,9 @@ public partial class ListViewModel : PageViewModel, IDisposable
             // building new viewmodels for the ones we haven't already built.
             foreach (var item in newItems)
             {
+                // Check for cancellation during item processing
+                cancellationToken.ThrowIfCancellationRequested();
+
                 ListItemViewModel viewModel = new(item, new(this));
 
                 // If an item fails to load, silently ignore it.
@@ -154,15 +171,22 @@ public partial class ListViewModel : PageViewModel, IDisposable
                 }
             }
 
+            // Check for cancellation before initializing first twenty items
+            cancellationToken.ThrowIfCancellationRequested();
+
             var firstTwenty = newViewModels.Take(20);
             foreach (var item in firstTwenty)
             {
+                cancellationToken.ThrowIfCancellationRequested();
                 item?.SafeInitializeProperties();
             }
 
             // Cancel any ongoing search
             _cancellationTokenSource?.Cancel();
 
+            // Check for cancellation before updating the list
+            cancellationToken.ThrowIfCancellationRequested();
+
             lock (_listLock)
             {
                 // Now that we have new ViewModels for everything from the
@@ -173,6 +197,11 @@ public partial class ListViewModel : PageViewModel, IDisposable
             // TODO: Iterate over everything in Items, and prune items from the
             // cache if we don't need them anymore
         }
+        catch (OperationCanceledException)
+        {
+            // Cancellation is expected, don't treat as error
+            return;
+        }
         catch (Exception ex)
         {
             // TODO: Move this within the for loop, so we can catch issues with individual items
@@ -298,11 +327,11 @@ public partial class ListViewModel : PageViewModel, IDisposable
     [RelayCommand]
     private void InvokeItem(ListItemViewModel? item)
     {
-        if (item != null)
+        if (item is not null)
         {
             WeakReferenceMessenger.Default.Send<PerformCommandMessage>(new(item.Command.Model, item.Model));
         }
-        else if (ShowEmptyContent && EmptyContent.PrimaryCommand?.Model.Unsafe != null)
+        else if (ShowEmptyContent && EmptyContent.PrimaryCommand?.Model.Unsafe is not null)
         {
             WeakReferenceMessenger.Default.Send<PerformCommandMessage>(new(
                 EmptyContent.PrimaryCommand.Command.Model,
@@ -314,14 +343,14 @@ public partial class ListViewModel : PageViewModel, IDisposable
     [RelayCommand]
     private void InvokeSecondaryCommand(ListItemViewModel? item)
     {
-        if (item != null)
+        if (item is not null)
         {
-            if (item.SecondaryCommand != null)
+            if (item.SecondaryCommand is not null)
             {
                 WeakReferenceMessenger.Default.Send<PerformCommandMessage>(new(item.SecondaryCommand.Command.Model, item.Model));
             }
         }
-        else if (ShowEmptyContent && EmptyContent.SecondaryCommand?.Model.Unsafe != null)
+        else if (ShowEmptyContent && EmptyContent.SecondaryCommand?.Model.Unsafe is not null)
         {
             WeakReferenceMessenger.Default.Send<PerformCommandMessage>(new(
                 EmptyContent.SecondaryCommand.Command.Model,
@@ -332,12 +361,12 @@ public partial class ListViewModel : PageViewModel, IDisposable
     [RelayCommand]
     private void UpdateSelectedItem(ListItemViewModel? item)
     {
-        if (_lastSelectedItem != null)
+        if (_lastSelectedItem is not null)
         {
             _lastSelectedItem.PropertyChanged -= SelectedItemPropertyChanged;
         }
 
-        if (item != null)
+        if (item is not null)
         {
             SetSelectedItem(item);
         }
@@ -383,7 +412,7 @@ public partial class ListViewModel : PageViewModel, IDisposable
     private void SelectedItemPropertyChanged(object? sender, System.ComponentModel.PropertyChangedEventArgs e)
     {
         var item = _lastSelectedItem;
-        if (item == null)
+        if (item is null)
         {
             return;
         }
@@ -438,7 +467,7 @@ public partial class ListViewModel : PageViewModel, IDisposable
         base.InitializeProperties();
 
         var model = _model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -465,7 +494,7 @@ public partial class ListViewModel : PageViewModel, IDisposable
     public void LoadMoreIfNeeded()
     {
         var model = this._model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
@@ -509,7 +538,7 @@ public partial class ListViewModel : PageViewModel, IDisposable
         base.FetchProperty(propertyName);
 
         var model = this._model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -540,7 +569,7 @@ public partial class ListViewModel : PageViewModel, IDisposable
     private void UpdateEmptyContent()
     {
         UpdateProperty(nameof(ShowEmptyContent));
-        if (!ShowEmptyContent || EmptyContent.Model.Unsafe == null)
+        if (!ShowEmptyContent || EmptyContent.Model.Unsafe is null)
         {
             return;
         }
@@ -560,6 +589,10 @@ public partial class ListViewModel : PageViewModel, IDisposable
         _cancellationTokenSource?.Cancel();
         _cancellationTokenSource?.Dispose();
         _cancellationTokenSource = null;
+
+        _fetchItemsCancellationTokenSource?.Cancel();
+        _fetchItemsCancellationTokenSource?.Dispose();
+        _fetchItemsCancellationTokenSource = null;
     }
 
     protected override void UnsafeCleanup()
@@ -570,6 +603,7 @@ public partial class ListViewModel : PageViewModel, IDisposable
         EmptyContent = new(new(null), PageContext); // necessary?
 
         _cancellationTokenSource?.Cancel();
+        _fetchItemsCancellationTokenSource?.Cancel();
 
         lock (_listLock)
         {
@@ -588,7 +622,7 @@ public partial class ListViewModel : PageViewModel, IDisposable
         }
 
         var model = _model.Unsafe;
-        if (model != null)
+        if (model is not null)
         {
             model.ItemsChanged -= Model_ItemsChanged;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/LogMessageViewModel.cs

@@ -22,7 +22,7 @@ public partial class LogMessageViewModel : ExtensionObjectViewModel
     public override void InitializeProperties()
     {
         var model = _model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/PageViewModel.cs

@@ -5,6 +5,7 @@
 using System.Collections.ObjectModel;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
+using Microsoft.CmdPal.Common.Helpers;
 using Microsoft.CmdPal.Core.ViewModels.Models;
 using Microsoft.CommandPalette.Extensions;
 
@@ -45,7 +46,7 @@ public partial class PageViewModel : ExtensionObjectViewModel, IPageContext
     [ObservableProperty]
     public partial AppExtensionHost ExtensionHost { get; private set; }
 
-    public bool HasStatusMessage => MostRecentStatusMessage != null;
+    public bool HasStatusMessage => MostRecentStatusMessage is not null;
 
     [ObservableProperty]
     [NotifyPropertyChangedFor(nameof(HasStatusMessage))]
@@ -132,7 +133,7 @@ public partial class PageViewModel : ExtensionObjectViewModel, IPageContext
     public override void InitializeProperties()
     {
         var page = _pageModel.Unsafe;
-        if (page == null)
+        if (page is null)
         {
             return; // throw?
         }
@@ -177,7 +178,7 @@ public partial class PageViewModel : ExtensionObjectViewModel, IPageContext
     protected virtual void FetchProperty(string propertyName)
     {
         var model = this._pageModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -223,9 +224,10 @@ public partial class PageViewModel : ExtensionObjectViewModel, IPageContext
         extensionHint ??= ExtensionHost.GetExtensionDisplayName() ?? Title;
         Task.Factory.StartNew(
             () =>
-        {
-            ErrorMessage += $"A bug occurred in {$"the \"{extensionHint}\"" ?? "an unknown's"} extension's code:\n{ex.Message}\n{ex.Source}\n{ex.StackTrace}\n\n";
-        },
+            {
+                var message = DiagnosticsHelper.BuildExceptionMessage(ex, extensionHint);
+                ErrorMessage += message;
+            },
             CancellationToken.None,
             TaskCreationOptions.None,
             Scheduler);
@@ -240,7 +242,7 @@ public partial class PageViewModel : ExtensionObjectViewModel, IPageContext
         ExtensionHost.StatusMessages.CollectionChanged -= StatusMessages_CollectionChanged;
 
         var model = _pageModel.Unsafe;
-        if (model != null)
+        if (model is not null)
         {
             model.PropChanged -= Model_PropChanged;
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/ProgressViewModel.cs

@@ -24,7 +24,7 @@ public partial class ProgressViewModel : ExtensionObjectViewModel
     public override void InitializeProperties()
     {
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -50,7 +50,7 @@ public partial class ProgressViewModel : ExtensionObjectViewModel
     protected virtual void FetchProperty(string propertyName)
     {
         var model = this.Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/ShellViewModel.cs

@@ -120,7 +120,7 @@ public partial class ShellViewModel : ObservableObject,
 
         ////LoadedState = ViewModelLoadedState.Loading;
         if (!viewModel.IsInitialized
-            && viewModel.InitializeCommand != null)
+            && viewModel.InitializeCommand is not null)
         {
             _ = Task.Run(async () =>
             {
@@ -185,7 +185,7 @@ public partial class ShellViewModel : ObservableObject,
     private void PerformCommand(PerformCommandMessage message)
     {
         var command = message.Command.Unsafe;
-        if (command == null)
+        if (command is null)
         {
             return;
         }
@@ -205,7 +205,7 @@ public partial class ShellViewModel : ObservableObject,
 
                 // Construct our ViewModel of the appropriate type and pass it the UI Thread context.
                 var pageViewModel = _pageViewModelFactory.TryCreatePageViewModel(page, _isNested, host);
-                if (pageViewModel == null)
+                if (pageViewModel is null)
                 {
                     Logger.LogError($"Failed to create ViewModel for page {page.GetType().Name}");
                     throw new NotSupportedException();
@@ -240,7 +240,7 @@ public partial class ShellViewModel : ObservableObject,
         // TODO GH #525 This needs more better locking.
         lock (_invokeLock)
         {
-            if (_handleInvokeTask != null)
+            if (_handleInvokeTask is not null)
             {
                 // do nothing - a command is already doing a thing
             }
@@ -280,7 +280,7 @@ public partial class ShellViewModel : ObservableObject,
 
     private void UnsafeHandleCommandResult(ICommandResult? result)
     {
-        if (result == null)
+        if (result is null)
         {
             // No result, nothing to do.
             return;

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/StatusMessageViewModel.cs

@@ -17,7 +17,7 @@ public partial class StatusMessageViewModel : ExtensionObjectViewModel
 
     public ProgressViewModel? Progress { get; private set; }
 
-    public bool HasProgress => Progress != null;
+    public bool HasProgress => Progress is not null;
 
     public StatusMessageViewModel(IStatusMessage message, WeakReference<IPageContext> context)
         : base(context)
@@ -28,7 +28,7 @@ public partial class StatusMessageViewModel : ExtensionObjectViewModel
     public override void InitializeProperties()
     {
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -36,7 +36,7 @@ public partial class StatusMessageViewModel : ExtensionObjectViewModel
         Message = model.Message;
         State = model.State;
         var modelProgress = model.Progress;
-        if (modelProgress != null)
+        if (modelProgress is not null)
         {
             Progress = new(modelProgress, this.PageContext);
             Progress.InitializeProperties();
@@ -61,7 +61,7 @@ public partial class StatusMessageViewModel : ExtensionObjectViewModel
     protected virtual void FetchProperty(string propertyName)
     {
         var model = this.Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -76,7 +76,7 @@ public partial class StatusMessageViewModel : ExtensionObjectViewModel
                 break;
             case nameof(Progress):
                 var modelProgress = model.Progress;
-                if (modelProgress != null)
+                if (modelProgress is not null)
                 {
                     Progress = new(modelProgress, this.PageContext);
                     Progress.InitializeProperties();

src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/TagViewModel.cs

@@ -28,7 +28,7 @@ public partial class TagViewModel(ITag _tag, WeakReference<IPageContext> context
     public override void InitializeProperties()
     {
         var model = _tagModel.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }

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

@@ -35,7 +35,7 @@ public partial class AliasManager : ObservableObject
             try
             {
                 var topLevelCommand = _topLevelCommandManager.LookupCommand(alias.CommandId);
-                if (topLevelCommand != null)
+                if (topLevelCommand is not null)
                 {
                     WeakReferenceMessenger.Default.Send<ClearSearchMessage>();
 
@@ -88,7 +88,7 @@ public partial class AliasManager : ObservableObject
         }
 
         // If we already have _this exact alias_, do nothing
-        if (newAlias != null &&
+        if (newAlias is not null &&
             _aliases.TryGetValue(newAlias.SearchPrefix, out var existingAlias))
         {
             if (existingAlias.CommandId == commandId)
@@ -113,7 +113,7 @@ public partial class AliasManager : ObservableObject
             _aliases.Remove(alias.SearchPrefix);
         }
 
-        if (newAlias != null)
+        if (newAlias is not null)
         {
             AddAlias(newAlias);
         }

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

@@ -55,7 +55,7 @@ public partial class AppStateModel : ObservableObject
 
             var loaded = JsonSerializer.Deserialize<AppStateModel>(jsonContent, JsonSerializationContext.Default.AppStateModel);
 
-            Debug.WriteLine(loaded != null ? "Loaded settings file" : "Failed to parse");
+            Debug.WriteLine(loaded is not null ? "Loaded settings file" : "Failed to parse");
 
             return loaded ?? new();
         }

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

@@ -15,7 +15,7 @@ namespace Microsoft.CmdPal.UI.ViewModels;
 
 public sealed class CommandProviderWrapper
 {
-    public bool IsExtension => Extension != null;
+    public bool IsExtension => Extension is not null;
 
     private readonly bool isValid;
 
@@ -188,14 +188,14 @@ public sealed class CommandProviderWrapper
 
             return topLevelViewModel;
         };
-        if (commands != null)
+        if (commands is not null)
         {
             TopLevelItems = commands
                 .Select(c => makeAndAdd(c, false))
                 .ToArray();
         }
 
-        if (fallbacks != null)
+        if (fallbacks is not null)
         {
             FallbackItems = fallbacks
                 .Select(c => makeAndAdd(c, true))

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

@@ -18,18 +18,18 @@ public partial class CommandSettingsViewModel(ICommandSettings? _unsafeSettings,
     public bool Initialized { get; private set; }
 
     public bool HasSettings =>
-        _model.Unsafe != null && // We have a settings model AND
-        (!Initialized || SettingsPage != null); // we weren't initialized, OR we were, and we do have a settings page
+        _model.Unsafe is not null && // We have a settings model AND
+        (!Initialized || SettingsPage is not null); // we weren't initialized, OR we were, and we do have a settings page
 
     private void UnsafeInitializeProperties()
     {
         var model = _model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
 
-        if (model.SettingsPage != null)
+        if (model.SettingsPage is not null)
         {
             SettingsPage = new CommandPaletteContentPageViewModel(model.SettingsPage, mainThread, provider.ExtensionHost);
             SettingsPage.InitializeProperties();

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Commands/CreatedExtensionForm.cs

@@ -30,7 +30,7 @@ internal sealed partial class CreatedExtensionForm : NewExtensionFormBase
     public override ICommandResult SubmitForm(string inputs, string data)
     {
         var dataInput = JsonNode.Parse(data)?.AsObject();
-        if (dataInput == null)
+        if (dataInput is null)
         {
             return CommandResult.KeepOpen();
         }

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Commands/LogMessagesPage.cs

@@ -23,7 +23,7 @@ public partial class LogMessagesPage : ListPage
 
     private void LogMessages_CollectionChanged(object? sender, NotifyCollectionChangedEventArgs e)
     {
-        if (e.Action == NotifyCollectionChangedAction.Add && e.NewItems != null)
+        if (e.Action == NotifyCollectionChangedAction.Add && e.NewItems is not null)
         {
             foreach (var item in e.NewItems)
             {

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Commands/MainListPage.cs

@@ -203,7 +203,7 @@ public partial class MainListPage : DynamicListPage,
 
             // If we don't have any previous filter results to work with, start
             // with a list of all our commands & apps.
-            if (_filteredItems == null)
+            if (_filteredItems is null)
             {
                 _filteredItems = commands;
                 _filteredItemsIncludesApps = _includeApps;

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Commands/NewExtensionForm.cs

@@ -98,7 +98,7 @@ internal sealed partial class NewExtensionForm : NewExtensionFormBase
     public override CommandResult SubmitForm(string payload)
     {
         var formInput = JsonNode.Parse(payload)?.AsObject();
-        if (formInput == null)
+        if (formInput is null)
         {
             return CommandResult.KeepOpen();
         }

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Commands/NewExtensionPage.cs

@@ -14,7 +14,7 @@ public partial class NewExtensionPage : ContentPage
 
     public override IContent[] GetContent()
     {
-        return _resultForm != null ? [_resultForm] : [_inputForm];
+        return _resultForm is not null ? [_resultForm] : [_inputForm];
     }
 
     public NewExtensionPage()
@@ -28,13 +28,13 @@ public partial class NewExtensionPage : ContentPage
 
     private void FormSubmitted(NewExtensionFormBase sender, NewExtensionFormBase? args)
     {
-        if (_resultForm != null)
+        if (_resultForm is not null)
         {
             _resultForm.FormSubmitted -= FormSubmitted;
         }
 
         _resultForm = args;
-        if (_resultForm != null)
+        if (_resultForm is not null)
         {
             _resultForm.FormSubmitted += FormSubmitted;
         }

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

@@ -20,7 +20,7 @@ public partial class ContentMarkdownViewModel(IMarkdownContent _markdown, WeakRe
     public override void InitializeProperties()
     {
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
@@ -47,7 +47,7 @@ public partial class ContentMarkdownViewModel(IMarkdownContent _markdown, WeakRe
     protected void FetchProperty(string propertyName)
     {
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -66,7 +66,7 @@ public partial class ContentMarkdownViewModel(IMarkdownContent _markdown, WeakRe
     {
         base.UnsafeCleanup();
         var model = Model.Unsafe;
-        if (model != null)
+        if (model is not null)
         {
             model.PropChanged -= Model_PropChanged;
         }

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

@@ -30,13 +30,13 @@ public partial class ContentTreeViewModel(ITreeContent _tree, WeakReference<IPag
     public override void InitializeProperties()
     {
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return;
         }
 
         var root = model.RootContent;
-        if (root != null)
+        if (root is not null)
         {
             RootContent = ViewModelFromContent(root, PageContext);
             RootContent?.InitializeProperties();
@@ -82,7 +82,7 @@ public partial class ContentTreeViewModel(ITreeContent _tree, WeakReference<IPag
     protected void FetchProperty(string propertyName)
     {
         var model = Model.Unsafe;
-        if (model == null)
+        if (model is null)
         {
             return; // throw?
         }
@@ -91,7 +91,7 @@ public partial class ContentTreeViewModel(ITreeContent _tree, WeakReference<IPag
         {
             case nameof(RootContent):
                 var root = model.RootContent;
-                if (root != null)
+                if (root is not null)
                 {
                     RootContent = ViewModelFromContent(root, PageContext);
                 }
@@ -119,7 +119,7 @@ public partial class ContentTreeViewModel(ITreeContent _tree, WeakReference<IPag
             foreach (var item in newItems)
             {
                 var viewModel = ViewModelFromContent(item, PageContext);
-                if (viewModel != null)
+                if (viewModel is not null)
                 {
                     viewModel.InitializeProperties();
                     newContent.Add(viewModel);
@@ -153,7 +153,7 @@ public partial class ContentTreeViewModel(ITreeContent _tree, WeakReference<IPag
 
         Children.Clear();
         var model = Model.Unsafe;
-        if (model != null)
+        if (model is not null)
         {
             model.PropChanged -= Model_PropChanged;
             model.ItemsChanged -= Model_ItemsChanged;

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

@@ -29,7 +29,7 @@ public partial class HotkeyManager : ObservableObject
             }
         }
 
-        _commandHotkeys.RemoveAll(item => item.Hotkey == null);
+        _commandHotkeys.RemoveAll(item => item.Hotkey is null);
 
         foreach (var item in _commandHotkeys)
         {

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Models/ExtensionService.cs

@@ -90,7 +90,7 @@ public partial class ExtensionService : IExtensionService, IDisposable
         }).Result;
         var isExtension = isCmdPalExtensionResult.IsExtension;
         var extension = isCmdPalExtensionResult.Extension;
-        if (isExtension && extension != null)
+        if (isExtension && extension is not null)
         {
             CommandPaletteHost.Instance.DebugLog($"Installed new extension app {extension.DisplayName}");
 
@@ -152,7 +152,7 @@ public partial class ExtensionService : IExtensionService, IDisposable
             {
                 var (cmdPalProvider, classId) = await GetCmdPalExtensionPropertiesAsync(extension);
 
-                return new(cmdPalProvider != null && classId.Count != 0, extension);
+                return new(cmdPalProvider is not null && classId.Count != 0, extension);
             }
         }
 
@@ -237,7 +237,7 @@ public partial class ExtensionService : IExtensionService, IDisposable
     {
         var (cmdPalProvider, classIds) = await GetCmdPalExtensionPropertiesAsync(extension);
 
-        if (cmdPalProvider == null || classIds.Count == 0)
+        if (cmdPalProvider is null || classIds.Count == 0)
         {
             return [];
         }
@@ -352,12 +352,12 @@ public partial class ExtensionService : IExtensionService, IDisposable
     {
         var propSetList = new List<string>();
         var singlePropertySet = GetSubPropertySet(activationPropSet, CreateInstanceProperty);
-        if (singlePropertySet != null)
+        if (singlePropertySet is not null)
         {
             var classId = GetProperty(singlePropertySet, ClassIdProperty);
 
             // If the instance has a classId as a single string, then it's only supporting a single instance.
-            if (classId != null)
+            if (classId is not null)
             {
                 propSetList.Add(classId);
             }
@@ -365,7 +365,7 @@ public partial class ExtensionService : IExtensionService, IDisposable
         else
         {
             var propertySetArray = GetSubPropertySetArray(activationPropSet, CreateInstanceProperty);
-            if (propertySetArray != null)
+            if (propertySetArray is not null)
             {
                 foreach (var prop in propertySetArray)
                 {
@@ -375,7 +375,7 @@ public partial class ExtensionService : IExtensionService, IDisposable
                     }
 
                     var classId = GetProperty(propertySet, ClassIdProperty);
-                    if (classId != null)
+                    if (classId is not null)
                     {
                         propSetList.Add(classId);
                     }

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

@@ -35,7 +35,7 @@ public class ProviderSettings
     public void Connect(CommandProviderWrapper wrapper)
     {
         ProviderId = wrapper.ProviderId;
-        IsBuiltin = wrapper.Extension == null;
+        IsBuiltin = wrapper.Extension is null;
 
         ProviderDisplayName = wrapper.DisplayName;
 

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

@@ -33,7 +33,7 @@ public partial class ProviderSettingsViewModel(
         Resources.builtin_disabled_extension;
 
     [MemberNotNullWhen(true, nameof(Extension))]
-    public bool IsFromExtension => _provider.Extension != null;
+    public bool IsFromExtension => _provider.Extension is not null;
 
     public IExtensionWrapper? Extension => _provider.Extension;
 
@@ -76,7 +76,7 @@ public partial class ProviderSettingsViewModel(
     {
         get
         {
-            if (_provider.Settings == null)
+            if (_provider.Settings is null)
             {
                 return false;
             }
@@ -100,7 +100,7 @@ public partial class ProviderSettingsViewModel(
     {
         get
         {
-            if (_provider.Settings == null)
+            if (_provider.Settings is null)
             {
                 return null;
             }
@@ -126,7 +126,7 @@ public partial class ProviderSettingsViewModel(
     {
         get
         {
-            if (field == null)
+            if (field is null)
             {
                 field = BuildTopLevelViewModels();
             }
@@ -149,7 +149,7 @@ public partial class ProviderSettingsViewModel(
     {
         get
         {
-            if (field == null)
+            if (field is null)
             {
                 field = BuildFallbackViewModels();
             }
@@ -173,7 +173,7 @@ public partial class ProviderSettingsViewModel(
 
     private void InitializeSettingsPage()
     {
-        if (_provider.Settings == null)
+        if (_provider.Settings is null)
         {
             return;
         }

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

@@ -30,7 +30,7 @@ public partial class RecentCommandsManager : ObservableObject
             // These numbers are vaguely scaled so that "VS" will make "Visual Studio" the
             // match after one use.
             // Usually it has a weight of 84, compared to 109 for the VS cmd prompt
-            if (entry.Item != null)
+            if (entry.Item is not null)
             {
                 var index = entry.Index;
 
@@ -61,7 +61,7 @@ public partial class RecentCommandsManager : ObservableObject
             var entry = History
             .Where(item => item.CommandId == commandId)
             .FirstOrDefault();
-            if (entry == null)
+            if (entry is null)
             {
                 var newitem = new HistoryItem() { CommandId = commandId, Uses = 1 };
                 History.Insert(0, newitem);

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

@@ -95,7 +95,7 @@ public partial class SettingsModel : ObservableObject
 
             var loaded = JsonSerializer.Deserialize<SettingsModel>(jsonContent, JsonSerializationContext.Default.SettingsModel);
 
-            Debug.WriteLine(loaded != null ? "Loaded settings file" : "Failed to parse");
+            Debug.WriteLine(loaded is not null ? "Loaded settings file" : "Failed to parse");
 
             return loaded ?? new();
         }

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

@@ -249,7 +249,7 @@ public partial class TopLevelCommandManager : ObservableObject,
             _extensionCommandProviders.Clear();
         }
 
-        if (extensions != null)
+        if (extensions is not null)
         {
             await StartExtensionsAndGetCommands(extensions);
         }
@@ -283,7 +283,7 @@ public partial class TopLevelCommandManager : ObservableObject,
         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();
+        var wrappers = (await Task.WhenAll(startTasks)).Where(wrapper => wrapper is not null).Select(w => w!).ToList();
 
         lock (_commandProvidersLock)
         {
@@ -293,7 +293,7 @@ public partial class TopLevelCommandManager : ObservableObject,
         // 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();
+        var commandSets = (await Task.WhenAll(loadTasks)).Where(results => results is not null).Select(r => r!).ToList();
 
         lock (TopLevelCommands)
         {
@@ -410,8 +410,8 @@ public partial class TopLevelCommandManager : ObservableObject,
 
     void IPageContext.ShowException(Exception ex, string? extensionHint)
     {
-        var errorMessage = $"A bug occurred in {$"the \"{extensionHint}\"" ?? "an unknown's"} extension's code:\n{ex.Message}\n{ex.Source}\n{ex.StackTrace}\n\n";
-        CommandPaletteHost.Instance.Log(errorMessage);
+        var message = DiagnosticsHelper.BuildExceptionMessage(ex, extensionHint ?? "TopLevelCommandManager");
+        CommandPaletteHost.Instance.Log(message);
     }
 
     internal bool IsProviderActive(string id)

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

@@ -240,7 +240,7 @@ public sealed partial class TopLevelViewModel : ObservableObject, IListItem
     private void FetchAliasFromAliasManager()
     {
         var am = _serviceProvider.GetService<AliasManager>();
-        if (am != null)
+        if (am is not null)
         {
             var commandAlias = am.AliasFromId(Id);
             if (commandAlias is not null)
@@ -254,7 +254,7 @@ public sealed partial class TopLevelViewModel : ObservableObject, IListItem
     private void UpdateHotkey()
     {
         var hotkey = _settings.CommandHotkeys.Where(hk => hk.CommandId == Id).FirstOrDefault();
-        if (hotkey != null)
+        if (hotkey is not null)
         {
             _hotkey = hotkey.Hotkey;
         }
@@ -264,12 +264,12 @@ public sealed partial class TopLevelViewModel : ObservableObject, IListItem
     {
         List<Tag> tags = [];
 
-        if (Hotkey != null)
+        if (Hotkey is not null)
         {
             tags.Add(new Tag() { Text = Hotkey.ToString() });
         }
 
-        if (Alias != null)
+        if (Alias is not null)
         {
             tags.Add(new Tag() { Text = Alias.SearchPrefix });
         }

src/modules/cmdpal/Microsoft.CmdPal.UI/Controls/CommandBar.xaml

@@ -47,7 +47,8 @@
             <Flyout
                 x:Name="ContextMenuFlyout"
                 FlyoutPresenterStyle="{StaticResource ContextMenuFlyoutStyle}"
-                Opened="ContextMenuFlyout_Opened">
+                Opened="ContextMenuFlyout_Opened"
+                ShouldConstrainToRootBounds="False">
                 <cpcontrols:ContextMenu x:Name="ContextControl" />
             </Flyout>
 

src/modules/cmdpal/Microsoft.CmdPal.UI/Controls/CommandBar.xaml.cs

@@ -10,7 +10,6 @@ using Microsoft.CmdPal.UI.Views;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
 using Microsoft.UI.Xaml.Controls.Primitives;
-using Microsoft.UI.Xaml.Input;
 using Windows.System;
 
 namespace Microsoft.CmdPal.UI.Controls;
@@ -50,7 +49,7 @@ public sealed partial class CommandBar : UserControl,
             return;
         }
 
-        if (message.Element == null)
+        if (message.Element is null)
         {
             _ = DispatcherQueue.TryEnqueue(
                 () =>

src/modules/cmdpal/Microsoft.CmdPal.UI/Controls/ContentFormControl.xaml.cs

@@ -44,7 +44,7 @@ public sealed partial class ContentFormControl : UserControl
         // 5% BODGY: if we set this multiple times over the lifetime of the app,
         // then the second call will explode, because "CardOverrideStyles is already the child of another element".
         // SO only set this once.
-        if (_renderer.OverrideStyles == null)
+        if (_renderer.OverrideStyles is null)
         {
             _renderer.OverrideStyles = CardOverrideStyles;
         }
@@ -55,19 +55,19 @@ public sealed partial class ContentFormControl : UserControl
 
     private void AttachViewModel(ContentFormViewModel? vm)
     {
-        if (_viewModel != null)
+        if (_viewModel is not null)
         {
             _viewModel.PropertyChanged -= ViewModel_PropertyChanged;
         }
 
         _viewModel = vm;
 
-        if (_viewModel != null)
+        if (_viewModel is not null)
         {
             _viewModel.PropertyChanged += ViewModel_PropertyChanged;
 
             var c = _viewModel.Card;
-            if (c != null)
+            if (c is not null)
             {
                 DisplayCard(c);
             }
@@ -76,7 +76,7 @@ public sealed partial class ContentFormControl : UserControl
 
     private void ViewModel_PropertyChanged(object? sender, System.ComponentModel.PropertyChangedEventArgs e)
     {
-        if (ViewModel == null)
+        if (ViewModel is null)
         {
             return;
         }
@@ -84,7 +84,7 @@ public sealed partial class ContentFormControl : UserControl
         if (e.PropertyName == nameof(ViewModel.Card))
         {
             var c = ViewModel.Card;
-            if (c != null)
+            if (c is not null)
             {
                 DisplayCard(c);
             }
@@ -95,7 +95,7 @@ public sealed partial class ContentFormControl : UserControl
     {
         _renderedCard = _renderer.RenderAdaptiveCard(result.AdaptiveCard);
         ContentGrid.Children.Clear();
-        if (_renderedCard.FrameworkElement != null)
+        if (_renderedCard.FrameworkElement is not null)
         {
             ContentGrid.Children.Add(_renderedCard.FrameworkElement);
 
@@ -148,7 +148,7 @@ public sealed partial class ContentFormControl : UserControl
 
             // Recursively check children
             var result = FindFirstFocusableElement(child);
-            if (result != null)
+            if (result is not null)
             {
                 return result;
             }

src/modules/cmdpal/Microsoft.CmdPal.UI/Controls/ContextMenu.xaml.cs

@@ -31,7 +31,7 @@ public sealed partial class ContextMenu : UserControl,
         WeakReferenceMessenger.Default.Register<UpdateCommandBarMessage>(this);
         WeakReferenceMessenger.Default.Register<TryCommandKeybindingMessage>(this);
 
-        if (ViewModel != null)
+        if (ViewModel is not null)
         {
             ViewModel.PropertyChanged += ViewModel_PropertyChanged;
         }

src/modules/cmdpal/Microsoft.CmdPal.UI/Controls/IconBox.cs

@@ -91,7 +91,7 @@ public partial class IconBox : ContentControl
     {
         if (d is IconBox @this)
         {
-            if (e.NewValue == null)
+            if (e.NewValue is null)
             {
                 @this.Source = null;
             }
@@ -104,7 +104,7 @@ public partial class IconBox : ContentControl
                     var requestedTheme = @this.ActualTheme;
                     var eventArgs = new SourceRequestedEventArgs(e.NewValue, requestedTheme);
 
-                    if (@this.SourceRequested != null)
+                    if (@this.SourceRequested is not null)
                     {
                         await @this.SourceRequested.InvokeAsync(@this, eventArgs);
 
@@ -142,7 +142,7 @@ public partial class IconBox : ContentControl
                             iconData = requestedTheme == ElementTheme.Light ? info.Light : info.Dark;
                         }
 
-                        if (iconData != null &&
+                        if (iconData is not null &&
                             @this.Source is FontIconSource)
                         {
                             if (!string.IsNullOrEmpty(iconData.Icon) && iconData.Icon.Length <= 2)