[AOT] Refactor SettingsLib/SettingsUI for Native AOT compatibility (#42644)

<!-- Enter a brief description/summary of your PR here. What does it
fix/what does it change/how was it tested (even manually, if necessary)?
-->
## Summary of the Pull Request

Key Changes:

1. Settings.UI.Library:
- Added SettingsSerializationContext.cs with comprehensive
JsonSerializable attributes for all settings types
- Updated BasePTModuleSettings.ToJsonString() to use AOT-compatible
serialization
- Updated SettingsUtils.GetFile<T>() to use AOT-compatible
deserialization
- Modified all ToString() methods in Properties classes to use
SettingsSerializationContext
- Converted struct fields to properties in SunTimes and
MouseWithoutBordersProperties for serialization compatibility

2. Settings.UI:
- Fixed namespace alias in SourceGenerationContextContext.cs to avoid
conflicts

For any future developers who discover incorrect settings resolution,
please follow up my changes to add your setting type into
JsonSerilizerContext.



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## PR Checklist

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

<!-- Provide a more detailed description of the PR, other things fixed,
or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

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wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed

Co-authored-by: Yu Leng <yuleng@microsoft.com>

src/settings-ui/Settings.UI.Library/AdvancedPasteCustomActions.cs

@@ -10,7 +10,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library;
 
 public sealed class AdvancedPasteCustomActions
 {
-    private static readonly JsonSerializerOptions _serializerOptions = new()
+    private static readonly JsonSerializerOptions _serializerOptions = new(SettingsSerializationContext.Default.Options)
     {
         WriteIndented = true,
     };

src/settings-ui/Settings.UI.Library/AdvancedPasteProperties.cs

@@ -104,6 +104,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         public PasteAIConfiguration PasteAIConfiguration { get; set; }
 
         public override string ToString()
-            => JsonSerializer.Serialize(this);
+            => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.AdvancedPasteProperties);
     }
 }

src/settings-ui/Settings.UI.Library/BasePTModuleSettings.cs

@@ -2,13 +2,32 @@
 // 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.Text.Json;
 using System.Text.Json.Serialization;
 
 namespace Microsoft.PowerToys.Settings.UI.Library
 {
+    /// <summary>
+    /// Base class for all PowerToys module settings.
+    /// </summary>
+    /// <remarks>
+    /// <para><strong>IMPORTANT for Native AOT compatibility:</strong></para>
+    /// <para>When creating a new class that inherits from <see cref="BasePTModuleSettings"/>,
+    /// you MUST register it in <see cref="SettingsSerializationContext"/> by adding a
+    /// <c>[JsonSerializable(typeof(YourNewSettingsClass))]</c> attribute.</para>
+    /// <para>Failure to register the type will cause <see cref="ToJsonString"/> to throw
+    /// <see cref="InvalidOperationException"/> at runtime.</para>
+    /// <para>See <see cref="SettingsSerializationContext"/> for registration instructions.</para>
+    /// </remarks>
     public abstract class BasePTModuleSettings
     {
+        // Cached JsonSerializerOptions for Native AOT compatibility
+        private static readonly JsonSerializerOptions _jsonSerializerOptions = new JsonSerializerOptions
+        {
+            TypeInfoResolver = SettingsSerializationContext.Default,
+        };
+
         // Gets or sets name of the powertoy module.
         [JsonPropertyName("name")]
         public string Name { get; set; }
@@ -17,11 +36,33 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         [JsonPropertyName("version")]
         public string Version { get; set; }
 
-        // converts the current to a json string.
+        /// <summary>
+        /// Converts the current settings object to a JSON string.
+        /// </summary>
+        /// <returns>JSON string representation of this settings object.</returns>
+        /// <exception cref="InvalidOperationException">
+        /// Thrown when the runtime type is not registered in <see cref="SettingsSerializationContext"/>.
+        /// All derived types must be registered with <c>[JsonSerializable(typeof(YourType))]</c> attribute.
+        /// </exception>
+        /// <remarks>
+        /// This method uses Native AOT-compatible JSON serialization. The runtime type must be
+        /// registered in <see cref="SettingsSerializationContext"/> for serialization to work.
+        /// </remarks>
         public virtual string ToJsonString()
         {
             // By default JsonSerializer will only serialize the properties in the base class. This can be avoided by passing the object type (more details at https://stackoverflow.com/a/62498888)
-            return JsonSerializer.Serialize(this, GetType());
+            var runtimeType = GetType();
+
+            // For Native AOT compatibility, get JsonTypeInfo from the TypeInfoResolver
+            var typeInfo = _jsonSerializerOptions.TypeInfoResolver?.GetTypeInfo(runtimeType, _jsonSerializerOptions);
+
+            if (typeInfo == null)
+            {
+                throw new InvalidOperationException($"Type {runtimeType.FullName} is not registered in SettingsSerializationContext. Please add it to the [JsonSerializable] attributes.");
+            }
+
+            // Use AOT-friendly serialization
+            return JsonSerializer.Serialize(this, typeInfo);
         }
 
         public override int GetHashCode()

src/settings-ui/Settings.UI.Library/BoolProperty.cs

@@ -37,7 +37,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.BoolProperty);
         }
 
         public bool TryToCmdRepresentable(out string result)

src/settings-ui/Settings.UI.Library/BoolPropertyJsonConverter.cs

@@ -12,14 +12,14 @@ namespace Microsoft.PowerToys.Settings.UI.Library
     {
         public override bool Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
         {
-            var boolProperty = JsonSerializer.Deserialize<BoolProperty>(ref reader, options);
+            var boolProperty = JsonSerializer.Deserialize(ref reader, SettingsSerializationContext.Default.BoolProperty);
             return boolProperty.Value;
         }
 
         public override void Write(Utf8JsonWriter writer, bool value, JsonSerializerOptions options)
         {
             var boolProperty = new BoolProperty(value);
-            JsonSerializer.Serialize(writer, boolProperty, options);
+            JsonSerializer.Serialize(writer, boolProperty, SettingsSerializationContext.Default.BoolProperty);
         }
     }
 }

src/settings-ui/Settings.UI.Library/CmdPalProperties.cs

@@ -43,7 +43,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
                 if (doc.RootElement.TryGetProperty(nameof(Hotkey), out JsonElement hotkeyElement))
                 {
-                    Hotkey = JsonSerializer.Deserialize<HotkeySettings>(hotkeyElement.GetRawText());
+                    Hotkey = JsonSerializer.Deserialize(hotkeyElement.GetRawText(), SettingsSerializationContext.Default.HotkeySettings);
                 }
             }
             catch (Exception)

src/settings-ui/Settings.UI.Library/ColorPickerProperties.cs

@@ -87,6 +87,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         public bool ShowColorName { get; set; }
 
         public override string ToString()
-            => JsonSerializer.Serialize(this);
+            => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.ColorPickerProperties);
     }
 }

src/settings-ui/Settings.UI.Library/ColorPickerPropertiesVersion1.cs

@@ -54,6 +54,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         public bool ShowColorName { get; set; }
 
         public override string ToString()
-            => JsonSerializer.Serialize(this);
+            => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.ColorPickerPropertiesVersion1);
     }
 }

src/settings-ui/Settings.UI.Library/DoubleProperty.cs

@@ -27,7 +27,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         // Returns a JSON version of the class settings configuration class.
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.DoubleProperty);
         }
     }
 }

src/settings-ui/Settings.UI.Library/FileLocksmithLocalProperties.cs

@@ -21,7 +21,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.FileLocksmithLocalProperties);
         }
 
         // This function is required to implement the ISettingsConfig interface and obtain the settings configurations.

src/settings-ui/Settings.UI.Library/FileLocksmithProperties.cs

@@ -17,6 +17,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         [JsonPropertyName("bool_show_extended_menu")]
         public BoolProperty ExtendedContextMenuOnly { get; set; }
 
-        public override string ToString() => JsonSerializer.Serialize(this);
+        public override string ToString() => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.FileLocksmithProperties);
     }
 }

src/settings-ui/Settings.UI.Library/GeneralSettings.cs

@@ -119,7 +119,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         // converts the current to a json string.
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.GeneralSettings);
         }
 
         private static string DefaultPowertoysVersion()

src/settings-ui/Settings.UI.Library/GeneralSettingsCustomAction.cs

@@ -23,7 +23,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.GeneralSettingsCustomAction);
         }
     }
 }

src/settings-ui/Settings.UI.Library/Helpers/SunTimes.cs

@@ -12,13 +12,18 @@ namespace Microsoft.PowerToys.Settings.UI.Library.Helpers
 {
     public struct SunTimes
     {
-        public int SunriseHour;
-        public int SunriseMinute;
-        public int SunsetHour;
-        public int SunsetMinute;
-        public string Text;
+        public int SunriseHour { get; set; }
 
-        public bool HasSunrise;
-        public bool HasSunset;
+        public int SunriseMinute { get; set; }
+
+        public int SunsetHour { get; set; }
+
+        public int SunsetMinute { get; set; }
+
+        public string Text { get; set; }
+
+        public bool HasSunrise { get; set; }
+
+        public bool HasSunset { get; set; }
     }
 }

src/settings-ui/Settings.UI.Library/ImageResizerProperties.cs

@@ -86,7 +86,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.ImageResizerProperties);
         }
     }
 

src/settings-ui/Settings.UI.Library/ImageResizerSettings.cs

@@ -37,8 +37,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToJsonString()
         {
-            var options = _serializerOptions;
-            return JsonSerializer.Serialize(this, options);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.ImageResizerSettings);
         }
 
         public string GetModuleName()

src/settings-ui/Settings.UI.Library/IntProperty.cs

@@ -42,7 +42,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         // Returns a JSON version of the class settings configuration class.
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.IntProperty);
         }
 
         public static implicit operator IntProperty(int v)

src/settings-ui/Settings.UI.Library/KeyboardManagerProfile.cs

@@ -34,7 +34,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.KeyboardManagerProfile);
         }
 
         public string GetModuleName()

src/settings-ui/Settings.UI.Library/MeasureToolProperties.cs

@@ -46,6 +46,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public IntProperty DefaultMeasureStyle { get; set; }
 
-        public override string ToString() => JsonSerializer.Serialize(this);
+        public override string ToString() => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.MeasureToolProperties);
     }
 }

src/settings-ui/Settings.UI.Library/MouseWithoutBordersProperties.cs

@@ -15,8 +15,9 @@ namespace Microsoft.PowerToys.Settings.UI.Library
     public struct ConnectionRequest
 #pragma warning restore SA1649 // File name should match first type name
     {
-        public string PCName;
-        public string SecurityKey;
+        public string PCName { get; set; }
+
+        public string SecurityKey { get; set; }
     }
 
     public struct NewKeyGenerationRequest

src/settings-ui/Settings.UI.Library/NewPlusProperties.cs

@@ -33,6 +33,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         [JsonPropertyName("ReplaceVariables")]
         public BoolProperty ReplaceVariables { get; set; }
 
-        public override string ToString() => JsonSerializer.Serialize(this);
+        public override string ToString() => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.NewPlusProperties);
     }
 }

src/settings-ui/Settings.UI.Library/OutGoingGeneralSettings.cs

@@ -23,7 +23,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.OutGoingGeneralSettings);
         }
     }
 }

src/settings-ui/Settings.UI.Library/OutGoingLanguageSettings.cs

@@ -23,7 +23,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.OutGoingLanguageSettings);
         }
     }
 }

src/settings-ui/Settings.UI.Library/PasteAIConfiguration.cs

@@ -64,7 +64,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         public AIServiceType ActiveServiceTypeKind => ActiveProvider?.ServiceTypeKind ?? AIServiceType.OpenAI;
 
         public override string ToString()
-            => JsonSerializer.Serialize(this);
+            => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.PasteAIConfiguration);
 
         protected bool SetProperty<T>(ref T field, T value, [CallerMemberName] string propertyName = null)
         {

src/settings-ui/Settings.UI.Library/PeekPreviewSettings.cs

@@ -34,7 +34,7 @@ namespace Settings.UI.Library
 
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, Microsoft.PowerToys.Settings.UI.Library.SettingsSerializationContext.Default.PeekPreviewSettings);
         }
 
         public string GetModuleName()

src/settings-ui/Settings.UI.Library/PeekProperties.cs

@@ -32,6 +32,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public BoolProperty EnableSpaceToActivate { get; set; }
 
-        public override string ToString() => JsonSerializer.Serialize(this);
+        public override string ToString() => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.PeekProperties);
     }
 }

src/settings-ui/Settings.UI.Library/PowerOcrProperties.cs

@@ -24,6 +24,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         public string PreferredLanguage { get; set; }
 
         public override string ToString()
-            => JsonSerializer.Serialize(this);
+            => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.PowerOcrProperties);
     }
 }

src/settings-ui/Settings.UI.Library/PowerPreviewProperties.cs

@@ -340,7 +340,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.PowerPreviewProperties);
         }
 
         private static void LogTelemetryEvent(bool value, [CallerMemberName] string propertyName = null)

src/settings-ui/Settings.UI.Library/PowerRenameLocalProperties.cs

@@ -54,7 +54,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.PowerRenameLocalProperties);
         }
 
         // This function is required to implement the ISettingsConfig interface and obtain the settings configurations.

src/settings-ui/Settings.UI.Library/SettingsSerializationContext.cs

@@ -0,0 +1,172 @@
+// 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.Text.Json.Serialization;
+using SettingsUILibrary = Settings.UI.Library;
+using SettingsUILibraryHelpers = Settings.UI.Library.Helpers;
+
+namespace Microsoft.PowerToys.Settings.UI.Library
+{
+    /// <summary>
+    /// JSON serialization context for Native AOT compatibility.
+    /// This context provides source-generated serialization for all PowerToys settings types.
+    /// </summary>
+    /// <remarks>
+    /// <para><strong>⚠️ CRITICAL REQUIREMENT FOR ALL NEW SETTINGS CLASSES ⚠️</strong></para>
+    /// <para>
+    /// When adding a new PowerToys module or any class that inherits from <see cref="BasePTModuleSettings"/>,
+    /// you <strong>MUST</strong> add a <c>[JsonSerializable(typeof(YourNewSettingsClass))]</c> attribute
+    /// to this class. This is a MANDATORY step for Native AOT compatibility.
+    /// </para>
+    /// <para><strong>Steps to add a new settings class:</strong></para>
+    /// <list type="number">
+    /// <item><description>Create your new settings class (e.g., <c>MyNewModuleSettings</c>) that inherits from <see cref="BasePTModuleSettings"/></description></item>
+    /// <item><description>Add <c>[JsonSerializable(typeof(MyNewModuleSettings))]</c> attribute to this <see cref="SettingsSerializationContext"/> class</description></item>
+    /// <item><description>If you have a corresponding Properties class, also add <c>[JsonSerializable(typeof(MyNewModuleProperties))]</c></description></item>
+    /// <item><description>Rebuild the project - source generator will create serialization code at compile time</description></item>
+    /// </list>
+    /// <para><strong>⚠️ Failure to register types will cause runtime errors:</strong></para>
+    /// <para>
+    /// If you forget to add the <c>[JsonSerializable]</c> attribute, calling <c>ToJsonString()</c> or
+    /// deserialization methods will throw <see cref="InvalidOperationException"/> at runtime with a clear
+    /// error message indicating which type is missing registration.
+    /// </para>
+    /// </remarks>
+    [JsonSourceGenerationOptions(
+        WriteIndented = false,
+        DefaultIgnoreCondition = JsonIgnoreCondition.Never,
+        IncludeFields = true)]
+
+    // Main Settings Classes
+    [JsonSerializable(typeof(GeneralSettings))]
+    [JsonSerializable(typeof(AdvancedPasteSettings))]
+    [JsonSerializable(typeof(AlwaysOnTopSettings))]
+    [JsonSerializable(typeof(AwakeSettings))]
+    [JsonSerializable(typeof(CmdNotFoundSettings))]
+    [JsonSerializable(typeof(ColorPickerSettings))]
+    [JsonSerializable(typeof(ColorPickerSettingsVersion1))]
+    [JsonSerializable(typeof(CropAndLockSettings))]
+    [JsonSerializable(typeof(CursorWrapSettings))]
+    [JsonSerializable(typeof(EnvironmentVariablesSettings))]
+    [JsonSerializable(typeof(FancyZonesSettings))]
+    [JsonSerializable(typeof(FileLocksmithSettings))]
+    [JsonSerializable(typeof(FindMyMouseSettings))]
+    [JsonSerializable(typeof(HostsSettings))]
+    [JsonSerializable(typeof(ImageResizerSettings))]
+    [JsonSerializable(typeof(KeyboardManagerSettings))]
+    [JsonSerializable(typeof(SettingsUILibrary.LightSwitchSettings))]
+    [JsonSerializable(typeof(MeasureToolSettings))]
+    [JsonSerializable(typeof(MouseHighlighterSettings))]
+    [JsonSerializable(typeof(MouseJumpSettings))]
+    [JsonSerializable(typeof(MousePointerCrosshairsSettings))]
+    [JsonSerializable(typeof(MouseWithoutBordersSettings))]
+    [JsonSerializable(typeof(NewPlusSettings))]
+    [JsonSerializable(typeof(PeekSettings))]
+    [JsonSerializable(typeof(PowerAccentSettings))]
+    [JsonSerializable(typeof(PowerLauncherSettings))]
+    [JsonSerializable(typeof(PowerOcrSettings))]
+    [JsonSerializable(typeof(PowerPreviewSettings))]
+    [JsonSerializable(typeof(PowerRenameSettings))]
+    [JsonSerializable(typeof(RegistryPreviewSettings))]
+    [JsonSerializable(typeof(ShortcutGuideSettings))]
+    [JsonSerializable(typeof(WorkspacesSettings))]
+    [JsonSerializable(typeof(ZoomItSettings))]
+
+    // Properties Classes
+    [JsonSerializable(typeof(AdvancedPasteProperties))]
+    [JsonSerializable(typeof(AlwaysOnTopProperties))]
+    [JsonSerializable(typeof(AwakeProperties))]
+    [JsonSerializable(typeof(CmdPalProperties))]
+    [JsonSerializable(typeof(ColorPickerProperties))]
+    [JsonSerializable(typeof(ColorPickerPropertiesVersion1))]
+    [JsonSerializable(typeof(CropAndLockProperties))]
+    [JsonSerializable(typeof(CursorWrapProperties))]
+    [JsonSerializable(typeof(EnvironmentVariablesProperties))]
+    [JsonSerializable(typeof(FileLocksmithProperties))]
+    [JsonSerializable(typeof(FileLocksmithLocalProperties))]
+    [JsonSerializable(typeof(FindMyMouseProperties))]
+    [JsonSerializable(typeof(FZConfigProperties))]
+    [JsonSerializable(typeof(HostsProperties))]
+    [JsonSerializable(typeof(ImageResizerProperties))]
+    [JsonSerializable(typeof(KeyboardManagerProperties))]
+    [JsonSerializable(typeof(KeyboardManagerProfile))]
+    [JsonSerializable(typeof(LightSwitchProperties))]
+    [JsonSerializable(typeof(MeasureToolProperties))]
+    [JsonSerializable(typeof(MouseHighlighterProperties))]
+    [JsonSerializable(typeof(MouseJumpProperties))]
+    [JsonSerializable(typeof(MousePointerCrosshairsProperties))]
+    [JsonSerializable(typeof(MouseWithoutBordersProperties))]
+    [JsonSerializable(typeof(NewPlusProperties))]
+    [JsonSerializable(typeof(PeekProperties))]
+    [JsonSerializable(typeof(SettingsUILibrary.PeekPreviewSettings))]
+    [JsonSerializable(typeof(PowerAccentProperties))]
+    [JsonSerializable(typeof(PowerLauncherProperties))]
+    [JsonSerializable(typeof(PowerOcrProperties))]
+    [JsonSerializable(typeof(PowerPreviewProperties))]
+    [JsonSerializable(typeof(PowerRenameProperties))]
+    [JsonSerializable(typeof(PowerRenameLocalProperties))]
+    [JsonSerializable(typeof(RegistryPreviewProperties))]
+    [JsonSerializable(typeof(ShortcutConflictProperties))]
+    [JsonSerializable(typeof(ShortcutGuideProperties))]
+    [JsonSerializable(typeof(WorkspacesProperties))]
+    [JsonSerializable(typeof(ZoomItProperties))]
+
+    // Base Property Types (used throughout settings)
+    [JsonSerializable(typeof(BoolProperty))]
+    [JsonSerializable(typeof(StringProperty))]
+    [JsonSerializable(typeof(IntProperty))]
+    [JsonSerializable(typeof(DoubleProperty))]
+
+    // Helper and Utility Types
+    [JsonSerializable(typeof(HotkeySettings))]
+    [JsonSerializable(typeof(ColorFormatModel))]
+    [JsonSerializable(typeof(ImageSize))]
+    [JsonSerializable(typeof(KeysDataModel))]
+    [JsonSerializable(typeof(EnabledModules))]
+    [JsonSerializable(typeof(GeneralSettingsCustomAction))]
+    [JsonSerializable(typeof(OutGoingGeneralSettings))]
+    [JsonSerializable(typeof(OutGoingLanguageSettings))]
+    [JsonSerializable(typeof(AdvancedPasteCustomActions))]
+    [JsonSerializable(typeof(AdvancedPasteAdditionalActions))]
+    [JsonSerializable(typeof(AdvancedPasteCustomAction))]
+    [JsonSerializable(typeof(AdvancedPasteAdditionalAction))]
+    [JsonSerializable(typeof(AdvancedPastePasteAsFileAction))]
+    [JsonSerializable(typeof(AdvancedPasteTranscodeAction))]
+    [JsonSerializable(typeof(PasteAIConfiguration))]
+    [JsonSerializable(typeof(PasteAIProviderDefinition))]
+    [JsonSerializable(typeof(ImageResizerSizes))]
+    [JsonSerializable(typeof(ImageResizerCustomSizeProperty))]
+    [JsonSerializable(typeof(KeyboardKeysProperty))]
+    [JsonSerializable(typeof(SettingsUILibraryHelpers.SearchLocation))]
+
+    // IPC Send Message Wrapper Classes (Snd*)
+    [JsonSerializable(typeof(SndAwakeSettings))]
+    [JsonSerializable(typeof(SndCursorWrapSettings))]
+    [JsonSerializable(typeof(SndFindMyMouseSettings))]
+    [JsonSerializable(typeof(SndLightSwitchSettings))]
+    [JsonSerializable(typeof(SndMouseHighlighterSettings))]
+    [JsonSerializable(typeof(SndMouseJumpSettings))]
+    [JsonSerializable(typeof(SndMousePointerCrosshairsSettings))]
+    [JsonSerializable(typeof(SndPowerAccentSettings))]
+    [JsonSerializable(typeof(SndPowerPreviewSettings))]
+    [JsonSerializable(typeof(SndPowerRenameSettings))]
+    [JsonSerializable(typeof(SndShortcutGuideSettings))]
+
+    // IPC Message Generic Wrapper Types (SndModuleSettings<T>)
+    [JsonSerializable(typeof(SndModuleSettings<SndAwakeSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndCursorWrapSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndFindMyMouseSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndLightSwitchSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndMouseHighlighterSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndMouseJumpSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndMousePointerCrosshairsSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndPowerAccentSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndPowerPreviewSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndPowerRenameSettings>))]
+    [JsonSerializable(typeof(SndModuleSettings<SndShortcutGuideSettings>))]
+
+    public partial class SettingsSerializationContext : JsonSerializerContext
+    {
+    }
+}

src/settings-ui/Settings.UI.Library/SettingsUtils.cs

@@ -2,6 +2,8 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
+
 using System;
 using System.IO;
 using System.IO.Abstractions;
@@ -18,27 +20,28 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         private const string DefaultModuleName = "";
         private readonly IFile _file;
         private readonly ISettingsPath _settingsPath;
-
-        private static readonly JsonSerializerOptions _serializerOptions = new JsonSerializerOptions
-        {
-            MaxDepth = 0,
-            IncludeFields = true,
-        };
+        private readonly JsonSerializerOptions _serializerOptions;
 
         public SettingsUtils()
             : this(new FileSystem())
         {
         }
 
-        public SettingsUtils(IFileSystem fileSystem)
-            : this(fileSystem?.File, new SettingPath(fileSystem?.Directory, fileSystem?.Path))
+        public SettingsUtils(IFileSystem? fileSystem, JsonSerializerOptions? serializerOptions = null)
+            : this(fileSystem?.File!, new SettingPath(fileSystem?.Directory, fileSystem?.Path), serializerOptions)
         {
         }
 
-        public SettingsUtils(IFile file, ISettingsPath settingPath)
+        public SettingsUtils(IFile file, ISettingsPath settingPath, JsonSerializerOptions? serializerOptions = null)
         {
             _file = file ?? throw new ArgumentNullException(nameof(file));
             _settingsPath = settingPath;
+            _serializerOptions = serializerOptions ?? new JsonSerializerOptions
+            {
+                MaxDepth = 0,
+                IncludeFields = true,
+                TypeInfoResolver = SettingsSerializationContext.Default,
+            };
         }
 
         public bool SettingsExists(string powertoy = DefaultModuleName, string fileName = DefaultFileName)
@@ -108,7 +111,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         /// This function creates a file in the powertoy folder if it does not exist and returns an object with default properties.
         /// </summary>
         /// <returns>Deserialized json settings object.</returns>
-        public T GetSettingsOrDefault<T, T2>(string powertoy = DefaultModuleName, string fileName = DefaultFileName, Func<object, object> settingsUpgrader = null)
+        public T GetSettingsOrDefault<T, T2>(string powertoy = DefaultModuleName, string fileName = DefaultFileName, Func<object, object>? settingsUpgrader = null)
             where T : ISettingsConfig, new()
             where T2 : ISettingsConfig, new()
         {
@@ -128,7 +131,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
                 try
                 {
                     T2 oldSettings = GetSettings<T2>(powertoy, fileName);
-                    T newSettings = (T)settingsUpgrader(oldSettings);
+                    T newSettings = (T)settingsUpgrader!(oldSettings);
                     Logger.LogInfo($"Settings file {fileName} for {powertoy} was read successfully in the old format.");
 
                     // If the file needs to be modified, to save the new configurations accordingly.
@@ -156,7 +159,22 @@ namespace Microsoft.PowerToys.Settings.UI.Library
             return newSettingsItem;
         }
 
-        // Given the powerToy folder name and filename to be accessed, this function deserializes and returns the file.
+        /// <summary>
+        /// Deserializes settings from a JSON file.
+        /// </summary>
+        /// <typeparam name="T">The settings type to deserialize. Must be registered in <see cref="SettingsSerializationContext"/>.</typeparam>
+        /// <param name="powertoyFolderName">The PowerToy module folder name.</param>
+        /// <param name="fileName">The settings file name.</param>
+        /// <returns>Deserialized settings object of type T.</returns>
+        /// <exception cref="InvalidOperationException">
+        /// Thrown when type T is not registered in <see cref="SettingsSerializationContext"/>.
+        /// All settings types must be registered with <c>[JsonSerializable(typeof(T))]</c> attribute
+        /// for Native AOT compatibility.
+        /// </exception>
+        /// <remarks>
+        /// This method uses Native AOT-compatible JSON deserialization. Type T must be registered
+        /// in <see cref="SettingsSerializationContext"/> before calling this method.
+        /// </remarks>
         private T GetFile<T>(string powertoyFolderName = DefaultModuleName, string fileName = DefaultFileName)
         {
             // Adding Trim('\0') to overcome possible NTFS file corruption.
@@ -165,8 +183,16 @@ namespace Microsoft.PowerToys.Settings.UI.Library
             // The file itself did write the content correctly but something is off with the actual end of the file, hence the 0x00 bug
             var jsonSettingsString = _file.ReadAllText(_settingsPath.GetSettingsPath(powertoyFolderName, fileName)).Trim('\0');
 
-            var options = _serializerOptions;
-            return JsonSerializer.Deserialize<T>(jsonSettingsString, options);
+            // For Native AOT compatibility, get JsonTypeInfo from the TypeInfoResolver
+            var typeInfo = _serializerOptions.TypeInfoResolver?.GetTypeInfo(typeof(T), _serializerOptions);
+
+            if (typeInfo == null)
+            {
+                throw new InvalidOperationException($"Type {typeof(T).FullName} is not registered in SettingsSerializationContext. Please add it to the [JsonSerializable] attributes.");
+            }
+
+            // Use AOT-friendly deserialization
+            return (T)JsonSerializer.Deserialize(jsonSettingsString, typeInfo)!;
         }
 
         // Save settings to a json file.

src/settings-ui/Settings.UI.Library/StringProperty.cs

@@ -27,7 +27,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         // Returns a JSON version of the class settings configuration class.
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.StringProperty);
         }
 
         public static StringProperty ToStringProperty(string v)

src/settings-ui/Settings.UI.UnitTests/ModelsTests/BasePTModuleSettingsSerializationTests.cs

@@ -0,0 +1,127 @@
+// 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.Linq;
+using System.Reflection;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using Microsoft.PowerToys.Settings.UI.Library;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace CommonLibTest
+{
+    [TestClass]
+    public class BasePTModuleSettingsSerializationTests
+    {
+        /// <summary>
+        /// Test to verify that all classes derived from BasePTModuleSettings are registered
+        /// in the SettingsSerializationContext for Native AOT compatibility.
+        /// </summary>
+        [TestMethod]
+        public void AllBasePTModuleSettingsClasses_ShouldBeRegisteredInSerializationContext()
+        {
+            // Arrange
+            var assembly = typeof(BasePTModuleSettings).Assembly;
+            var settingsClasses = assembly.GetTypes()
+                .Where(t => typeof(BasePTModuleSettings).IsAssignableFrom(t) && !t.IsAbstract && t != typeof(BasePTModuleSettings))
+                .OrderBy(t => t.Name)
+                .ToList();
+
+            Assert.IsTrue(settingsClasses.Count > 0, "No BasePTModuleSettings derived classes found. This test may be broken.");
+
+            var jsonSerializerOptions = new JsonSerializerOptions
+            {
+                TypeInfoResolver = SettingsSerializationContext.Default,
+            };
+
+            var unregisteredTypes = new System.Collections.Generic.List<string>();
+
+            // Act & Assert
+            foreach (var settingsType in settingsClasses)
+            {
+                var typeInfo = jsonSerializerOptions.TypeInfoResolver?.GetTypeInfo(settingsType, jsonSerializerOptions);
+
+                if (typeInfo == null)
+                {
+                    unregisteredTypes.Add(settingsType.FullName ?? settingsType.Name);
+                }
+            }
+
+            // Assert
+            if (unregisteredTypes.Count > 0)
+            {
+                var errorMessage = $"The following {unregisteredTypes.Count} settings class(es) are NOT registered in SettingsSerializationContext:\n" +
+                                   $"{string.Join("\n", unregisteredTypes.Select(t => $"  - {t}"))}\n\n" +
+                                   $"Please add [JsonSerializable(typeof(ClassName))] attribute to SettingsSerializationContext.cs for each missing type.";
+                Assert.Fail(errorMessage);
+            }
+
+            // Print success message with count
+            Console.WriteLine($"✓ All {settingsClasses.Count} BasePTModuleSettings derived classes are properly registered in SettingsSerializationContext.");
+        }
+
+        /// <summary>
+        /// Test to verify that calling ToJsonString() on an unregistered type throws InvalidOperationException
+        /// with a helpful error message.
+        /// </summary>
+        [TestMethod]
+        [ExpectedException(typeof(InvalidOperationException))]
+        public void ToJsonString_UnregisteredType_ShouldThrowInvalidOperationException()
+        {
+            // Arrange
+            var unregisteredSettings = new UnregisteredTestSettings
+            {
+                Name = "UnregisteredModule",
+                Version = "1.0.0",
+            };
+
+            // Act - This should throw InvalidOperationException
+            var jsonString = unregisteredSettings.ToJsonString();
+
+            // Assert - Exception should be thrown, so this line should never be reached
+            Assert.Fail("Expected InvalidOperationException was not thrown.");
+        }
+
+        /// <summary>
+        /// Test to verify that the error message for unregistered types is helpful and contains
+        /// necessary information for developers.
+        /// </summary>
+        [TestMethod]
+        public void ToJsonString_UnregisteredType_ShouldHaveHelpfulErrorMessage()
+        {
+            // Arrange
+            var unregisteredSettings = new UnregisteredTestSettings
+            {
+                Name = "UnregisteredModule",
+                Version = "1.0.0",
+            };
+
+            // Act & Assert
+            try
+            {
+                var jsonString = unregisteredSettings.ToJsonString();
+                Assert.Fail("Expected InvalidOperationException was not thrown.");
+            }
+            catch (InvalidOperationException ex)
+            {
+                // Verify the error message contains helpful information
+                Assert.IsTrue(ex.Message.Contains("UnregisteredTestSettings"), "Error message should contain the type name.");
+                Assert.IsTrue(ex.Message.Contains("SettingsSerializationContext"), "Error message should mention SettingsSerializationContext.");
+                Assert.IsTrue(ex.Message.Contains("JsonSerializable"), "Error message should mention JsonSerializable attribute.");
+
+                Console.WriteLine($"✓ Error message is helpful: {ex.Message}");
+            }
+        }
+
+        /// <summary>
+        /// Test class that is intentionally NOT registered in SettingsSerializationContext
+        /// to verify error handling for unregistered types.
+        /// </summary>
+        private sealed class UnregisteredTestSettings : BasePTModuleSettings
+        {
+            // Intentionally empty - this class should NOT be registered in SettingsSerializationContext
+        }
+    }
+}

src/settings-ui/Settings.UI.UnitTests/ModelsTests/BasePTSettingsTest.cs

@@ -2,8 +2,10 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Text.Json;
 using Microsoft.PowerToys.Settings.UI.Library;
 using Microsoft.PowerToys.Settings.UI.Library.Interfaces;
+using Microsoft.PowerToys.Settings.UI.UnitTests;
 
 namespace Microsoft.PowerToys.Settings.UnitTest
 {
@@ -24,5 +26,11 @@ namespace Microsoft.PowerToys.Settings.UnitTest
         {
             return false;
         }
+
+        // Override ToJsonString to use test-specific serialization context
+        public override string ToJsonString()
+        {
+            return JsonSerializer.Serialize(this, TestSettingsSerializationContext.Default.BasePTSettingsTest);
+        }
     }
 }

src/settings-ui/Settings.UI.UnitTests/ModelsTests/SettingsUtilsTests.cs

@@ -9,6 +9,7 @@ using System.Text.Json;
 
 using Microsoft.PowerToys.Settings.UI.Library;
 using Microsoft.PowerToys.Settings.UI.Library.Interfaces;
+using Microsoft.PowerToys.Settings.UI.UnitTests;
 using Microsoft.PowerToys.Settings.UnitTest;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 
@@ -22,7 +23,13 @@ namespace CommonLibTest
         {
             // Arrange
             var mockFileSystem = new MockFileSystem();
-            var settingsUtils = new SettingsUtils(mockFileSystem);
+            var testSerializerOptions = new JsonSerializerOptions
+            {
+                MaxDepth = 0,
+                IncludeFields = true,
+                TypeInfoResolver = TestSettingsSerializationContext.Default,
+            };
+            var settingsUtils = new SettingsUtils(mockFileSystem, testSerializerOptions);
 
             string file_name = "\\test";
             string file_contents_correct_json_content = "{\"name\":\"powertoy module name\",\"version\":\"powertoy version\"}";
@@ -42,7 +49,13 @@ namespace CommonLibTest
         {
             // Arrange
             var mockFileSystem = new MockFileSystem();
-            var settingsUtils = new SettingsUtils(mockFileSystem);
+            var testSerializerOptions = new JsonSerializerOptions
+            {
+                MaxDepth = 0,
+                IncludeFields = true,
+                TypeInfoResolver = TestSettingsSerializationContext.Default,
+            };
+            var settingsUtils = new SettingsUtils(mockFileSystem, testSerializerOptions);
             string file_name = "test\\Test Folder";
             string file_contents_correct_json_content = "{\"name\":\"powertoy module name\",\"version\":\"powertoy version\"}";
 

src/settings-ui/Settings.UI.UnitTests/TestSettingsSerializationContext.cs

@@ -0,0 +1,22 @@
+// 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.Text.Json.Serialization;
+using Microsoft.PowerToys.Settings.UnitTest;
+
+namespace Microsoft.PowerToys.Settings.UI.UnitTests
+{
+    /// <summary>
+    /// JSON serialization context for unit tests.
+    /// This context provides source-generated serialization for test-specific types.
+    /// </summary>
+    [JsonSourceGenerationOptions(
+        WriteIndented = false,
+        DefaultIgnoreCondition = JsonIgnoreCondition.Never,
+        IncludeFields = true)]
+    [JsonSerializable(typeof(BasePTSettingsTest))]
+    public partial class TestSettingsSerializationContext : JsonSerializerContext
+    {
+    }
+}

src/settings-ui/Settings.UI.UnitTests/ViewModelTests/FancyZones.cs

@@ -6,6 +6,7 @@ using System;
 using System.Text.Json;
 
 using Microsoft.PowerToys.Settings.UI.Library;
+using Microsoft.PowerToys.Settings.UI.Library.Interfaces;
 using Microsoft.PowerToys.Settings.UI.UnitTests.BackwardsCompatibility;
 using Microsoft.PowerToys.Settings.UI.UnitTests.Mocks;
 using Microsoft.PowerToys.Settings.UI.ViewModels;
@@ -100,6 +101,22 @@ namespace ViewModelTests
             mockFancyZonesSettingsUtils = ISettingsUtilsMocks.GetStubSettingsUtils<FancyZonesSettings>();
         }
 
+        [TestCleanup]
+        public void CleanUp()
+        {
+            // Reset singleton instances to prevent state pollution between tests
+            ResetSettingsRepository<GeneralSettings>();
+            ResetSettingsRepository<FancyZonesSettings>();
+        }
+
+        private void ResetSettingsRepository<T>()
+            where T : class, ISettingsConfig, new()
+        {
+            var repositoryType = typeof(SettingsRepository<T>);
+            var field = repositoryType.GetField("settingsRepository", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Static);
+            field?.SetValue(null, null);
+        }
+
         [TestMethod]
         public void IsEnabledShouldDisableModuleWhenSuccessful()
         {

src/settings-ui/Settings.UI/SerializationContext/SourceGenerationContextContext.cs

@@ -10,7 +10,7 @@ using System.Text.Json.Serialization;
 using System.Threading.Tasks;
 using Microsoft.PowerToys.Settings.UI.Helpers;
 using Microsoft.PowerToys.Settings.UI.Library;
-using Settings.UI.Library;
+using SettingsUILibrary = Settings.UI.Library;
 
 namespace Microsoft.PowerToys.Settings.UI.SerializationContext;
 
@@ -23,7 +23,7 @@ namespace Microsoft.PowerToys.Settings.UI.SerializationContext;
 [JsonSerializable(typeof(FileLocksmithSettings))]
 [JsonSerializable(typeof(FindMyMouseSettings))]
 [JsonSerializable(typeof(IList<PowerToysReleaseInfo>))]
-[JsonSerializable(typeof(LightSwitchSettings))]
+[JsonSerializable(typeof(SettingsUILibrary.LightSwitchSettings))]
 [JsonSerializable(typeof(MeasureToolSettings))]
 [JsonSerializable(typeof(MouseHighlighterSettings))]
 [JsonSerializable(typeof(MouseJumpSettings))]