Make internal & private classes sealed where possible, to avoid code for virtual dispatch (#19719)

src/Umbraco.Cms.Api.Common/Configuration/ConfigureOpenIddict.cs

@@ -4,7 +4,7 @@ using Umbraco.Cms.Core.Configuration.Models;
 
 namespace Umbraco.Cms.Api.Common.Configuration;
 
-internal class ConfigureOpenIddict : IConfigureOptions<OpenIddictServerAspNetCoreOptions>
+internal sealed class ConfigureOpenIddict : IConfigureOptions<OpenIddictServerAspNetCoreOptions>
 {
     private readonly IOptions<GlobalSettings> _globalSettings;
 

src/Umbraco.Cms.Api.Common/Json/NamedSystemTextJsonInputFormatter.cs

@@ -4,7 +4,7 @@ using Microsoft.Extensions.Logging;
 
 namespace Umbraco.Cms.Api.Common.Json;
 
-internal class NamedSystemTextJsonInputFormatter : SystemTextJsonInputFormatter
+internal sealed class NamedSystemTextJsonInputFormatter : SystemTextJsonInputFormatter
 {
     private readonly string _jsonOptionsName;
 

src/Umbraco.Cms.Api.Common/Json/NamedSystemTextJsonOutputFormatter.cs

@@ -3,8 +3,7 @@ using Microsoft.AspNetCore.Mvc.Formatters;
 
 namespace Umbraco.Cms.Api.Common.Json;
 
-
-internal class NamedSystemTextJsonOutputFormatter : SystemTextJsonOutputFormatter
+internal sealed class NamedSystemTextJsonOutputFormatter : SystemTextJsonOutputFormatter
 {
     private readonly string _jsonOptionsName;
 

src/Umbraco.Cms.Api.Delivery/Configuration/ConfigureUmbracoMemberAuthenticationDeliveryApiSwaggerGenOptions.cs

@@ -26,7 +26,7 @@ public class ConfigureUmbracoMemberAuthenticationDeliveryApiSwaggerGenOptions :
         options.OperationFilter<DeliveryApiSecurityFilter>();
     }
 
-    private class DeliveryApiSecurityFilter : SwaggerFilterBase<ContentApiControllerBase>, IOperationFilter, IDocumentFilter
+    private sealed class DeliveryApiSecurityFilter : SwaggerFilterBase<ContentApiControllerBase>, IOperationFilter, IDocumentFilter
     {
         public void Apply(OpenApiOperation operation, OperationFilterContext context)
         {

src/Umbraco.Cms.Api.Delivery/Filters/ContextualizeFromAcceptHeadersAttribute.cs

@@ -13,7 +13,7 @@ internal sealed class ContextualizeFromAcceptHeadersAttribute : TypeFilterAttrib
     {
     }
 
-    private class LocalizeFromAcceptLanguageHeaderAttributeFilter : IActionFilter
+    private sealed class LocalizeFromAcceptLanguageHeaderAttributeFilter : IActionFilter
     {
         private readonly IRequestCultureService _requestCultureService;
         private readonly IRequestSegmmentService _requestSegmentService;

src/Umbraco.Cms.Api.Delivery/Filters/DeliveryApiAccessAttribute.cs

@@ -11,7 +11,7 @@ internal sealed class DeliveryApiAccessAttribute : TypeFilterAttribute
     {
     }
 
-    private class DeliveryApiAccessFilter : IActionFilter
+    private sealed class DeliveryApiAccessFilter : IActionFilter
     {
         private readonly IApiAccessService _apiAccessService;
         private readonly IRequestPreviewService _requestPreviewService;

src/Umbraco.Cms.Api.Delivery/Filters/DeliveryApiMediaAccessAttribute.cs

@@ -11,7 +11,7 @@ internal sealed class DeliveryApiMediaAccessAttribute : TypeFilterAttribute
     {
     }
 
-    private class DeliveryApiMediaAccessFilter : IActionFilter
+    private sealed class DeliveryApiMediaAccessFilter : IActionFilter
     {
         private readonly IApiAccessService _apiAccessService;
 

src/Umbraco.Cms.Api.Delivery/Filters/ValidateStartItemAttribute.cs

@@ -12,7 +12,7 @@ internal sealed class ValidateStartItemAttribute : TypeFilterAttribute
     {
     }
 
-    private class ValidateStartItemFilter : IActionFilter
+    private sealed class ValidateStartItemFilter : IActionFilter
     {
         private readonly IRequestStartItemProviderAccessor _requestStartItemProviderAccessor;
 

src/Umbraco.Cms.Api.Delivery/Rendering/RequestContextOutputExpansionStrategyV2.cs

@@ -124,7 +124,7 @@ internal sealed class RequestContextOutputExpansionStrategyV2 : IOutputExpansion
     private object? GetPropertyValue(IPublishedProperty property)
         => _propertyRenderer.GetPropertyValue(property, _expandProperties.Peek() is not null);
 
-    private class Node
+    private sealed class Node
     {
         public string Key { get; private set; } = string.Empty;
 

src/Umbraco.Cms.Api.Management/DependencyInjection/BackOfficeAuthBuilderExtensions.cs

@@ -79,7 +79,7 @@ public static class BackOfficeAuthBuilderExtensions
     }
 }
 
-internal class BackofficePipelineFilter : UmbracoPipelineFilter
+internal sealed class BackofficePipelineFilter : UmbracoPipelineFilter
 {
     public BackofficePipelineFilter(string name)
         : base(name)

src/Umbraco.Cms.Api.Management/Factories/PackagePresentationFactory.cs

@@ -13,7 +13,7 @@ using Umbraco.Extensions;
 
 namespace Umbraco.Cms.Api.Management.Factories;
 
-internal class PackagePresentationFactory : IPackagePresentationFactory
+internal sealed class PackagePresentationFactory : IPackagePresentationFactory
 {
     private readonly IUmbracoMapper _umbracoMapper;
     private readonly IRuntimeState _runtimeState;

src/Umbraco.Cms.Api.Management/Factories/WebhookPresentationFactory.cs

@@ -8,7 +8,7 @@ using Umbraco.Cms.Core.Webhooks;
 
 namespace Umbraco.Cms.Api.Management.Factories;
 
-internal class WebhookPresentationFactory : IWebhookPresentationFactory
+internal sealed class WebhookPresentationFactory : IWebhookPresentationFactory
 {
     private readonly WebhookEventCollection _webhookEventCollection;
     private readonly IHostingEnvironment _hostingEnvironment;

src/Umbraco.Cms.Api.Management/Filters/AppendEventMessagesAttribute.cs

@@ -21,7 +21,7 @@ public sealed class AppendEventMessagesAttribute : TypeFilterAttribute
     {
     }
 
-    private class AppendEventMessagesFilter : IActionFilter
+    private sealed class AppendEventMessagesFilter : IActionFilter
     {
         private readonly IEventMessagesFactory _eventMessagesFactory;
         private readonly IJsonSerializer _jsonSerializer;

src/Umbraco.Cms.Api.Management/Filters/UserPasswordEnsureMinimumResponseTimeAttribute.cs

@@ -4,14 +4,14 @@ using Umbraco.Cms.Core.Configuration.Models;
 
 namespace Umbraco.Cms.Api.Management.Filters;
 
-internal class UserPasswordEnsureMinimumResponseTimeAttribute : TypeFilterAttribute
+internal sealed class UserPasswordEnsureMinimumResponseTimeAttribute : TypeFilterAttribute
 {
     public UserPasswordEnsureMinimumResponseTimeAttribute()
         : base(typeof(UserPasswordEnsureMinimumResponseTimeFilter))
     {
     }
 
-    private class UserPasswordEnsureMinimumResponseTimeFilter : EnsureMinimumResponseTimeFilter
+    private sealed class UserPasswordEnsureMinimumResponseTimeFilter : EnsureMinimumResponseTimeFilter
     {
         public UserPasswordEnsureMinimumResponseTimeFilter(IOptions<UserPasswordConfigurationSettings> options)
             : base(options.Value.MinimumResponseTime)

src/Umbraco.Cms.Api.Management/Mapping/SectionMapper.cs

@@ -45,7 +45,7 @@ public static class SectionMapper
         return name;
     }
 
-    private class SectionMapping
+    private sealed class SectionMapping
     {
         public required string Alias { get; init; }
 

src/Umbraco.Cms.Api.Management/OpenApi/BackOfficeSecurityRequirementsOperationFilter.cs

@@ -2,7 +2,7 @@ using Umbraco.Cms.Api.Management.DependencyInjection;
 
 namespace Umbraco.Cms.Api.Management.OpenApi;
 
-internal class BackOfficeSecurityRequirementsOperationFilter : BackOfficeSecurityRequirementsOperationFilterBase
+internal sealed class BackOfficeSecurityRequirementsOperationFilter : BackOfficeSecurityRequirementsOperationFilterBase
 {
     protected override string ApiName => ManagementApiConfiguration.ApiName;
 }

src/Umbraco.Cms.Api.Management/OpenApi/NotificationHeaderFilter.cs

@@ -6,7 +6,7 @@ using Umbraco.Cms.Core;
 
 namespace Umbraco.Cms.Api.Management.OpenApi;
 
-internal class NotificationHeaderFilter : IOperationFilter
+internal sealed class NotificationHeaderFilter : IOperationFilter
 {
     public void Apply(OpenApiOperation operation, OperationFilterContext context)
     {

src/Umbraco.Cms.Api.Management/OpenApi/ReponseHeaderOperationFilter.cs

@@ -7,7 +7,7 @@ using Umbraco.Extensions;
 
 namespace Umbraco.Cms.Api.Management.OpenApi;
 
-internal class ResponseHeaderOperationFilter : IOperationFilter
+internal sealed class ResponseHeaderOperationFilter : IOperationFilter
 {
     public void Apply(OpenApiOperation operation, OperationFilterContext context)
     {
@@ -29,7 +29,7 @@ internal class ResponseHeaderOperationFilter : IOperationFilter
         }
     }
 
-    private void SetHeader(OpenApiResponse value, string headerName, string description, string type, string? format = null)
+    private static void SetHeader(OpenApiResponse value, string headerName, string description, string type, string? format = null)
     {
 
         if (value.Headers is null)

src/Umbraco.Cms.Api.Management/Security/BackOfficeAuthenticationBuilder.cs

@@ -61,7 +61,7 @@ public class BackOfficeAuthenticationBuilder : AuthenticationBuilder
     // TODO: We could override and throw NotImplementedException for other methods?
 
     // Ensures that the sign in scheme is always the Umbraco back office external type
-    internal class EnsureBackOfficeScheme<TOptions> : IPostConfigureOptions<TOptions>
+    internal sealed class EnsureBackOfficeScheme<TOptions> : IPostConfigureOptions<TOptions>
         where TOptions : RemoteAuthenticationOptions
     {
         public void PostConfigure(string? name, TOptions options)

src/Umbraco.Cms.Api.Management/Security/BackOfficeSecureDataFormat.cs

@@ -7,7 +7,7 @@ namespace Umbraco.Cms.Api.Management.Security;
 /// <summary>
 ///     Custom secure format that ensures the Identity in the ticket is verified <see cref="ClaimsIdentity" />
 /// </summary>
-internal class BackOfficeSecureDataFormat : ISecureDataFormat<AuthenticationTicket>
+internal sealed class BackOfficeSecureDataFormat : ISecureDataFormat<AuthenticationTicket>
 {
     private readonly TimeSpan _loginTimeout;
     private readonly ISecureDataFormat<AuthenticationTicket> _ticketDataFormat;

src/Umbraco.Core/Cache/PartialViewCacheInvalidators/NoopMemberPartialViewCacheInvalidator.cs

@@ -7,7 +7,7 @@ namespace Umbraco.Cms.Core.Cache.PartialViewCacheInvalidators;
 /// The default implementation is added in Umbraco.Web.Website, but we need this to ensure we have a service
 /// registered for this interface even in headless setups).
 /// </remarks>
-internal class NoopMemberPartialViewCacheInvalidator : IMemberPartialViewCacheInvalidator
+internal sealed class NoopMemberPartialViewCacheInvalidator : IMemberPartialViewCacheInvalidator
 {
     /// <inheritdoc/>
     public void ClearPartialViewCacheItems(IEnumerable<int> memberIds)

src/Umbraco.Core/Composing/ComposerGraph.cs

@@ -11,7 +11,7 @@ namespace Umbraco.Cms.Core.Composing;
 /// <summary>
 ///     Handles the composers.
 /// </summary>
-internal class ComposerGraph
+internal sealed class ComposerGraph
 {
     private readonly IUmbracoBuilder _builder;
     private readonly IEnumerable<Type> _composerTypes;
@@ -415,7 +415,7 @@ internal class ComposerGraph
         }
     }
 
-    private class EnableInfo
+    private sealed class EnableInfo
     {
         public bool Enabled { get; set; }
 

src/Umbraco.Core/Composing/FindAssembliesWithReferencesTo.cs

@@ -11,7 +11,7 @@ namespace Umbraco.Cms.Core.Composing;
 ///     borrowed and modified from here
 ///     https://github.com/dotnet/aspnetcore-tooling/blob/master/src/Razor/src/Microsoft.NET.Sdk.Razor/FindAssembliesWithReferencesTo.cs
 /// </remarkes>
-internal class FindAssembliesWithReferencesTo
+internal sealed class FindAssembliesWithReferencesTo
 {
     private readonly bool _includeTargets;
     private readonly ILogger<FindAssembliesWithReferencesTo> _logger;

src/Umbraco.Core/Composing/TypeLoader.cs

@@ -408,7 +408,7 @@ public sealed class TypeLoader
     /// </summary>
     /// <seealso cref="System.Exception" />
     [Serializable]
-    internal class CachedTypeNotFoundInFileException : Exception
+    internal sealed class CachedTypeNotFoundInFileException : Exception
     {
         /// <summary>
         ///     Initializes a new instance of the <see cref="CachedTypeNotFoundInFileException" /> class.

src/Umbraco.Core/Configuration/EntryAssemblyMetadata.cs

@@ -2,7 +2,7 @@ using System.Reflection;
 
 namespace Umbraco.Cms.Core.Configuration;
 
-internal class EntryAssemblyMetadata : IEntryAssemblyMetadata
+internal sealed class EntryAssemblyMetadata : IEntryAssemblyMetadata
 {
     public EntryAssemblyMetadata()
     {

src/Umbraco.Core/Configuration/Models/ContentErrorPage.cs

@@ -37,7 +37,7 @@ public class ContentErrorPage : ValidatableEntryBase
     [Required]
     public string Culture { get; set; } = null!;
 
-    internal override bool IsValid() =>
+    internal sealed override bool IsValid() =>
         base.IsValid() &&
         (HasContentId ^ HasContentKey);
 }

src/Umbraco.Core/Diagnostics/NoopMarchal.cs

@@ -1,6 +1,6 @@
 namespace Umbraco.Cms.Core.Diagnostics;
 
-internal class NoopMarchal : IMarchal
+internal sealed class NoopMarchal : IMarchal
 {
     public IntPtr GetExceptionPointers() => IntPtr.Zero;
 }

src/Umbraco.Core/Dictionary/UmbracoCultureDictionary.cs

@@ -17,7 +17,7 @@ namespace Umbraco.Cms.Core.Dictionary;
 ///     fast
 ///     (even though there is caching involved, if there's lots of dictionary items the caching is not great)
 /// </remarks>
-internal class DefaultCultureDictionary : ICultureDictionary
+internal sealed class DefaultCultureDictionary : ICultureDictionary
 {
     private readonly ILocalizationService _localizationService;
     private readonly IAppCache _requestCache;

src/Umbraco.Core/EnvironmentHelper.cs

@@ -5,7 +5,7 @@ namespace Umbraco.Cms.Core;
 /// <summary>
 ///     Currently just used to get the machine name for use with file names
 /// </summary>
-internal class EnvironmentHelper
+internal static class EnvironmentHelper
 {
     /// <summary>
     ///     Returns the machine name that is safe to use in file paths.

src/Umbraco.Core/Events/EventAggregator.Notifications.cs

@@ -102,7 +102,7 @@ public partial class EventAggregator : IEventAggregator
         }
     }
 
-    private void PublishCore<TNotification>(IEnumerable<Action<IEnumerable<TNotification>>> allHandlers, IEnumerable<TNotification> notifications)
+    private static void PublishCore<TNotification>(IEnumerable<Action<IEnumerable<TNotification>>> allHandlers, IEnumerable<TNotification> notifications)
     {
         foreach (Action<IEnumerable<TNotification>> handler in allHandlers)
         {
@@ -110,7 +110,7 @@ public partial class EventAggregator : IEventAggregator
         }
     }
 
-    private async Task PublishCoreAsync<TNotification>(IEnumerable<Func<IEnumerable<TNotification>, CancellationToken, Task>> allHandlers, IEnumerable<TNotification> notifications, CancellationToken cancellationToken)
+    private static async Task PublishCoreAsync<TNotification>(IEnumerable<Func<IEnumerable<TNotification>, CancellationToken, Task>> allHandlers, IEnumerable<TNotification> notifications, CancellationToken cancellationToken)
     {
         foreach (Func<IEnumerable<TNotification>, CancellationToken, Task> handler in allHandlers)
         {
@@ -192,7 +192,7 @@ internal abstract class NotificationAsyncHandlerWrapper
         where TNotificationHandler : INotificationHandler;
 }
 
-internal class NotificationAsyncHandlerWrapperImpl<TNotificationType> : NotificationAsyncHandlerWrapper
+internal sealed class NotificationAsyncHandlerWrapperImpl<TNotificationType> : NotificationAsyncHandlerWrapper
     where TNotificationType : INotification
 {
     /// <remarks>
@@ -260,7 +260,7 @@ internal class NotificationAsyncHandlerWrapperImpl<TNotificationType> : Notifica
     }
 }
 
-internal class NotificationHandlerWrapperImpl<TNotificationType> : NotificationHandlerWrapper
+internal sealed class NotificationHandlerWrapperImpl<TNotificationType> : NotificationHandlerWrapper
     where TNotificationType : INotification
 {
     /// <remarks>

src/Umbraco.Core/Events/EventNameExtractor.cs

@@ -169,7 +169,7 @@ public class EventNameExtractor
         return words[0].EndsWith("ing") == false;
     }
 
-    private class EventInfoArgs
+    private sealed class EventInfoArgs
     {
         public EventInfoArgs(EventInfo eventInfo, Type[] genericArgs)
         {

src/Umbraco.Core/Events/PassThroughEventDispatcher.cs

@@ -7,7 +7,7 @@ namespace Umbraco.Cms.Core.Events;
 ///     This means that events will be raised during the scope transaction,
 ///     whatever happens, and the transaction could roll back in the end.
 /// </remarks>
-internal class PassThroughEventDispatcher : IEventDispatcher
+internal sealed class PassThroughEventDispatcher : IEventDispatcher
 {
     public bool DispatchCancelable(EventHandler? eventHandler, object sender, CancellableEventArgs args, string? eventName = null)
     {

src/Umbraco.Core/Events/QueuingEventDispatcherBase.cs

@@ -414,7 +414,7 @@ public abstract class QueuingEventDispatcherBase : IEventDispatcher
         }
     }
 
-    private class EventDefinitionInfos
+    private sealed class EventDefinitionInfos
     {
         public IEventDefinition? EventDefinition { get; set; }
 

src/Umbraco.Core/Events/ScopedNotificationPublisher.cs

@@ -116,7 +116,7 @@ public class ScopedNotificationPublisher<TNotificationHandler> : IScopedNotifica
     protected virtual void PublishScopedNotifications(IList<INotification> notifications)
         => _eventAggregator.Publish<INotification, TNotificationHandler>(notifications);
 
-    private class Suppressor : IDisposable
+    private sealed class Suppressor : IDisposable
     {
         private readonly ScopedNotificationPublisher<TNotificationHandler> _scopedNotificationPublisher;
         private bool _disposedValue;
@@ -129,7 +129,7 @@ public class ScopedNotificationPublisher<TNotificationHandler> : IScopedNotifica
 
         public void Dispose() => Dispose(true);
 
-        protected virtual void Dispose(bool disposing)
+        private void Dispose(bool disposing)
         {
             if (!_disposedValue)
             {

src/Umbraco.Core/Handlers/WarnDocumentTypeElementSwitchNotificationHandler.cs

@@ -96,7 +96,7 @@ public class WarnDocumentTypeElementSwitchNotificationHandler :
         }
     }
 
-    private class DocumentTypeElementSwitchInformation
+    private sealed class DocumentTypeElementSwitchInformation
     {
         public bool WasElement { get; set; }
     }

src/Umbraco.Core/Hosting/NoopApplicationShutdownRegistry.cs

@@ -1,6 +1,6 @@
 namespace Umbraco.Cms.Core.Hosting;
 
-internal class NoopApplicationShutdownRegistry : IApplicationShutdownRegistry
+internal sealed class NoopApplicationShutdownRegistry : IApplicationShutdownRegistry
 {
     public void RegisterObject(IRegisteredObject registeredObject)
     {

src/Umbraco.Core/IO/ShadowFileSystem.cs

@@ -2,7 +2,7 @@ using System.Text.RegularExpressions;
 
 namespace Umbraco.Cms.Core.IO;
 
-internal class ShadowFileSystem : IFileSystem
+internal sealed class ShadowFileSystem : IFileSystem
 {
     private readonly IFileSystem _sfs;
 
@@ -392,7 +392,7 @@ internal class ShadowFileSystem : IFileSystem
     }
 
     // copied from System.Web.Util.Wildcard internal
-    internal class WildcardExpression
+    internal sealed class WildcardExpression
     {
         private static readonly Regex MetaRegex = new("[\\+\\{\\\\\\[\\|\\(\\)\\.\\^\\$]");
         private static readonly Regex QuestRegex = new("\\?");
@@ -454,7 +454,7 @@ internal class ShadowFileSystem : IFileSystem
         }
     }
 
-    private class ShadowNode
+    private sealed class ShadowNode
     {
         public ShadowNode(bool isDelete, bool isdir)
         {

src/Umbraco.Core/IO/ShadowFileSystems.cs

@@ -1,7 +1,7 @@
 namespace Umbraco.Cms.Core.IO;
 
 // shadow filesystems is definitively ... too convoluted
-internal class ShadowFileSystems : ICompletable
+internal sealed class ShadowFileSystems : ICompletable
 {
     private readonly FileSystems _fileSystems;
     private bool _completed;

src/Umbraco.Core/IO/ShadowWrapper.cs

@@ -5,7 +5,7 @@ using Umbraco.Extensions;
 
 namespace Umbraco.Cms.Core.IO;
 
-internal class ShadowWrapper : IFileSystem, IFileProviderFactory
+internal sealed class ShadowWrapper : IFileSystem, IFileProviderFactory
 {
     private const string ShadowFsPath = "ShadowFs";
 

src/Umbraco.Core/Logging/LogProfiler.cs

@@ -39,7 +39,7 @@ public class LogProfiler : IProfiler
     public bool IsEnabled => _logger.IsEnabled(Microsoft.Extensions.Logging.LogLevel.Debug);
 
     // a lightweight disposable timer
-    private class LightDisposableTimer : DisposableObjectSlim
+    private sealed class LightDisposableTimer : DisposableObjectSlim
     {
         private readonly Action<long> _callback;
         private readonly Stopwatch _stopwatch = Stopwatch.StartNew();

src/Umbraco.Core/Logging/NoopProfiler.cs

@@ -17,7 +17,7 @@ public class NoopProfiler : IProfiler
     /// <inheritdoc/>
     public bool IsEnabled => false;
 
-    private class VoidDisposable : DisposableObjectSlim
+    private sealed class VoidDisposable : DisposableObjectSlim
     {
         protected override void DisposeResources()
         {

src/Umbraco.Core/Mail/NotImplementedEmailSender.cs

@@ -2,7 +2,7 @@ using Umbraco.Cms.Core.Models.Email;
 
 namespace Umbraco.Cms.Core.Mail;
 
-internal class NotImplementedEmailSender : IEmailSender
+internal sealed class NotImplementedEmailSender : IEmailSender
 {
     public Task SendAsync(EmailMessage message, string emailType)
         => throw new NotImplementedException(

src/Umbraco.Core/Mail/NotImplementedSmsSender.cs

@@ -3,7 +3,7 @@ namespace Umbraco.Cms.Core.Mail;
 /// <summary>
 ///     An <see cref="ISmsSender" /> that throws <see cref="NotImplementedException" />
 /// </summary>
-internal class NotImplementedSmsSender : ISmsSender
+internal sealed class NotImplementedSmsSender : ISmsSender
 {
     public Task SendSmsAsync(string number, string message)
         => throw new NotImplementedException(

src/Umbraco.Core/Models/DefaultPayloadModel.cs

@@ -1,6 +1,6 @@
 namespace Umbraco.Cms.Core.Models;
 
-internal class DefaultPayloadModel
+internal sealed class DefaultPayloadModel
 {
     public Guid Id { get; set; }
 }

src/Umbraco.Core/Models/Membership/User.cs

@@ -426,7 +426,7 @@ public class User : EntityBase, IUser, IProfile
     /// <summary>
     ///     Internal class used to wrap the user in a profile
     /// </summary>
-    private class WrappedUserProfile : IProfile
+    private sealed class WrappedUserProfile : IProfile
     {
         private readonly IUser _user;
 

src/Umbraco.Core/Models/PublishedContent/ModelType.cs

@@ -373,7 +373,7 @@ public class ModelType : Type
 }
 
 /// <inheritdoc />
-internal class ModelTypeArrayType : Type
+internal sealed class ModelTypeArrayType : Type
 {
     private readonly Type _elementType;
 

src/Umbraco.Core/Models/PublishedContent/PublishedContentTypeConverter.cs

@@ -3,7 +3,7 @@ using System.Globalization;
 
 namespace Umbraco.Cms.Core.Models.PublishedContent;
 
-internal class PublishedContentTypeConverter : TypeConverter
+internal sealed class PublishedContentTypeConverter : TypeConverter
 {
     private static readonly Type[] ConvertingTypes = { typeof(int) };
 

src/Umbraco.Core/Models/PublishedContent/PublishedModelFactory.cs

@@ -151,7 +151,7 @@ public class PublishedModelFactory : IPublishedModelFactory
     public Type MapModelType(Type type)
         => ModelType.Map(type, _modelTypeMap);
 
-    private class ModelInfo
+    private sealed class ModelInfo
     {
         public Type? ParameterType { get; set; }
 

src/Umbraco.Core/Persistence/Repositories/UpgradeCheckRepository.cs

@@ -33,7 +33,7 @@ public class UpgradeCheckRepository : IUpgradeCheckRepository
         }
     }
 
-    private class CheckUpgradeDto
+    private sealed class CheckUpgradeDto
     {
         public CheckUpgradeDto(SemVersion version)
         {

src/Umbraco.Core/PropertyEditors/ContentPickerConfigurationEditor.cs

@@ -5,7 +5,7 @@ using Umbraco.Cms.Core.IO;
 
 namespace Umbraco.Cms.Core.PropertyEditors;
 
-internal class ContentPickerConfigurationEditor : ConfigurationEditor<ContentPickerConfiguration>
+internal sealed class ContentPickerConfigurationEditor : ConfigurationEditor<ContentPickerConfiguration>
 {
     public ContentPickerConfigurationEditor(IIOHelper ioHelper)
         : base(ioHelper)

src/Umbraco.Core/PropertyEditors/ContentPickerPropertyEditor.cs

@@ -37,7 +37,7 @@ public class ContentPickerPropertyEditor : DataEditor
     protected override IDataValueEditor CreateValueEditor() =>
         DataValueEditorFactory.Create<ContentPickerPropertyValueEditor>(Attribute!);
 
-    internal class ContentPickerPropertyValueEditor : DataValueEditor, IDataValueReference
+    internal sealed class ContentPickerPropertyValueEditor : DataValueEditor, IDataValueReference
     {
 
         public ContentPickerPropertyValueEditor(

src/Umbraco.Core/PropertyEditors/DateValueEditor.cs

@@ -12,7 +12,7 @@ namespace Umbraco.Cms.Core.PropertyEditors;
 ///     CUstom value editor so we can serialize with the correct date format (excluding time)
 ///     and includes the date validator
 /// </summary>
-internal class DateValueEditor : DataValueEditor
+internal sealed class DateValueEditor : DataValueEditor
 {
     public DateValueEditor(
         IShortStringHelper shortStringHelper,

src/Umbraco.Core/PropertyEditors/DecimalPropertyEditor.cs

@@ -41,7 +41,7 @@ public class DecimalPropertyEditor : DataEditor
     /// <summary>
     /// Defines the value editor for the decimal property editor.
     /// </summary>
-    internal class DecimalPropertyValueEditor : DataValueEditor
+    internal sealed class DecimalPropertyValueEditor : DataValueEditor
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="DecimalPropertyValueEditor"/> class.
@@ -63,7 +63,7 @@ public class DecimalPropertyEditor : DataEditor
         public override object? FromEditor(ContentPropertyData editorValue, object? currentValue)
             => TryParsePropertyValue(editorValue.Value);
 
-        private decimal? TryParsePropertyValue(object? value)
+        private static decimal? TryParsePropertyValue(object? value)
             => value is decimal decimalValue
                 ? decimalValue
                 : decimal.TryParse(value?.ToString(), CultureInfo.InvariantCulture, out var parsedDecimalValue)
@@ -108,7 +108,7 @@ public class DecimalPropertyEditor : DataEditor
         /// <summary>
         /// Validates the min/max configuration for the decimal property editor.
         /// </summary>
-        internal class MinMaxValidator : DecimalPropertyConfigurationValidatorBase, IValueValidator
+        internal sealed class MinMaxValidator : DecimalPropertyConfigurationValidatorBase, IValueValidator
         {
             /// <summary>
             /// Initializes a new instance of the <see cref="MinMaxValidator"/> class.
@@ -145,7 +145,7 @@ public class DecimalPropertyEditor : DataEditor
         /// <summary>
         /// Validates the step configuration for the decimal property editor.
         /// </summary>
-        internal class StepValidator : DecimalPropertyConfigurationValidatorBase, IValueValidator
+        internal sealed class StepValidator : DecimalPropertyConfigurationValidatorBase, IValueValidator
         {
             /// <summary>
             /// Initializes a new instance of the <see cref="StepValidator"/> class.

src/Umbraco.Core/PropertyEditors/IntegerPropertyEditor.cs

@@ -39,7 +39,7 @@ public class IntegerPropertyEditor : DataEditor
     /// <summary>
     /// Defines the value editor for the integer property editor.
     /// </summary>
-    internal class IntegerPropertyValueEditor : DataValueEditor
+    internal sealed class IntegerPropertyValueEditor : DataValueEditor
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="IntegerPropertyValueEditor"/> class.
@@ -106,7 +106,7 @@ public class IntegerPropertyEditor : DataEditor
         /// <summary>
         /// Validates the min/max configuration for the integer property editor.
         /// </summary>
-        internal class MinMaxValidator : IntegerPropertyConfigurationValidatorBase, IValueValidator
+        internal sealed class MinMaxValidator : IntegerPropertyConfigurationValidatorBase, IValueValidator
         {
             /// <summary>
             /// Initializes a new instance of the <see cref="MinMaxValidator"/> class.
@@ -143,7 +143,7 @@ public class IntegerPropertyEditor : DataEditor
         /// <summary>
         /// Validates the step configuration for the integer property editor.
         /// </summary>
-        internal class StepValidator : IntegerPropertyConfigurationValidatorBase, IValueValidator
+        internal sealed class StepValidator : IntegerPropertyConfigurationValidatorBase, IValueValidator
         {
             /// <summary>
             /// Initializes a new instance of the <see cref="StepValidator"/> class.

src/Umbraco.Core/PropertyEditors/LabelPropertyEditor.cs

@@ -37,7 +37,7 @@ public class LabelPropertyEditor : DataEditor
         new LabelConfigurationEditor(_ioHelper);
 
     // provides the property value editor
-    internal class LabelPropertyValueEditor : DataValueEditor
+    internal sealed class LabelPropertyValueEditor : DataValueEditor
     {
         public LabelPropertyValueEditor(
             IShortStringHelper shortStringHelper,

src/Umbraco.Core/PropertyEditors/MarkDownPropertyValueEditor.cs

@@ -2,13 +2,12 @@ using Umbraco.Cms.Core.IO;
 using Umbraco.Cms.Core.Models.Editors;
 using Umbraco.Cms.Core.Security;
 using Umbraco.Cms.Core.Serialization;
-using Umbraco.Cms.Core.Services;
 using Umbraco.Cms.Core.Strings;
 using Umbraco.Extensions;
 
 namespace Umbraco.Cms.Core.PropertyEditors;
 
-internal class MarkDownPropertyValueEditor : DataValueEditor
+internal sealed class MarkDownPropertyValueEditor : DataValueEditor
 {
     private readonly IMarkdownSanitizer _markdownSanitizer;
 

src/Umbraco.Core/PropertyEditors/MemberGroupPickerPropertyEditor.cs

@@ -21,7 +21,7 @@ public class MemberGroupPickerPropertyEditor : DataEditor
     protected override IDataValueEditor CreateValueEditor() =>
         DataValueEditorFactory.Create<MemberGroupPickerPropertyValueEditor>(Attribute!);
 
-    private class MemberGroupPickerPropertyValueEditor : DataValueEditor
+    private sealed class MemberGroupPickerPropertyValueEditor : DataValueEditor
     {
         private readonly IMemberGroupService _memberGroupService;
 

src/Umbraco.Core/PropertyEditors/MemberPickerPropertyEditor.cs

@@ -21,7 +21,7 @@ public class MemberPickerPropertyEditor : DataEditor
     protected override IDataValueEditor CreateValueEditor() =>
         DataValueEditorFactory.Create<MemberPickerPropertyValueEditor>(Attribute!);
 
-    private class MemberPickerPropertyValueEditor : DataValueEditor, IDataValueReference
+    private sealed class MemberPickerPropertyValueEditor : DataValueEditor, IDataValueReference
     {
         private readonly IMemberService _memberService;
 

src/Umbraco.Core/PropertyEditors/TextOnlyValueEditor.cs

@@ -63,7 +63,7 @@ public class TextOnlyValueEditor : DataValueEditor
     /// <summary>
     /// A common length validator for both textbox and text area.
     /// </summary>
-    internal class LengthValidator : IValueValidator
+    internal sealed class LengthValidator : IValueValidator
     {
         private readonly ILocalizedTextService _localizedTextService;
 

src/Umbraco.Core/PropertyEditors/UserPickerPropertyEditor.cs

@@ -21,7 +21,7 @@ public class UserPickerPropertyEditor : DataEditor
     protected override IDataValueEditor CreateValueEditor() =>
         DataValueEditorFactory.Create<UserPickerPropertyValueEditor>(Attribute!);
 
-    private class UserPickerPropertyValueEditor : DataValueEditor
+    private sealed class UserPickerPropertyValueEditor : DataValueEditor
     {
         private readonly IUserService _userService;
 

src/Umbraco.Core/PropertyEditors/Validation/JsonPathValidationError.cs

@@ -1,6 +1,6 @@
 namespace Umbraco.Cms.Core.PropertyEditors.Validation;
 
-internal class JsonPathValidationError
+internal sealed class JsonPathValidationError
 {
     public required string JsonPath { get; init; }
 

src/Umbraco.Core/PropertyEditors/Validation/JsonPathValidator.cs

@@ -55,7 +55,7 @@ internal static class JsonPathValidator
         return errors;
     }
 
-    private class JsonPathValidationTreeItem
+    private sealed class JsonPathValidationTreeItem
     {
         public required string JsonPath { get; init; }
 

src/Umbraco.Core/PublishedCache/PublishedElementPropertyBase.cs

@@ -4,7 +4,7 @@ using Umbraco.Extensions;
 
 namespace Umbraco.Cms.Core.PublishedCache;
 
-internal class PublishedElementPropertyBase : PublishedPropertyBase
+internal sealed class PublishedElementPropertyBase : PublishedPropertyBase
 {
     protected readonly IPublishedElement Element;
 

src/Umbraco.Core/Security/Authorization/DictionaryPermissionAuthorizer.cs

@@ -4,7 +4,7 @@ using Umbraco.Cms.Core.Services.AuthorizationStatus;
 
 namespace Umbraco.Cms.Core.Security.Authorization;
 
-internal class DictionaryPermissionAuthorizer : IDictionaryPermissionAuthorizer
+internal sealed class DictionaryPermissionAuthorizer : IDictionaryPermissionAuthorizer
 {
     private readonly IDictionaryPermissionService _dictionaryPermissionService;
 

src/Umbraco.Core/Services/ConsentService.cs

@@ -10,7 +10,7 @@ namespace Umbraco.Cms.Core.Services;
 /// <summary>
 ///     Implements <see cref="IConsentService" />.
 /// </summary>
-internal class ConsentService : RepositoryService, IConsentService
+internal sealed class ConsentService : RepositoryService, IConsentService
 {
     private readonly IConsentRepository _consentRepository;
 

src/Umbraco.Core/Services/ContentVersionService.cs

@@ -13,7 +13,7 @@ using Umbraco.Extensions;
 // ReSharper disable once CheckNamespace
 namespace Umbraco.Cms.Core.Services;
 
-internal class ContentVersionService : IContentVersionService
+internal sealed class ContentVersionService : IContentVersionService
 {
     private readonly IAuditRepository _auditRepository;
     private readonly IContentVersionCleanupPolicy _contentVersionCleanupPolicy;

src/Umbraco.Core/Services/DocumentUrlService.cs

@@ -45,7 +45,7 @@ public class DocumentUrlService : IDocumentUrlService
     /// Model used to cache a single published document along with all it's URL segments.
     /// </summary>
     /// <remarks>Internal for the purpose of unit and benchmark testing.</remarks>
-    internal class PublishedDocumentUrlSegments
+    internal sealed class PublishedDocumentUrlSegments
     {
         /// <summary>
         /// Gets or sets the document key.
@@ -456,7 +456,7 @@ public class DocumentUrlService : IDocumentUrlService
     private static bool IsVariantAndPublishedForCulture(IContent document, string? culture) =>
         document.PublishCultureInfos?.Values.Any(x => x.Culture == culture) ?? false;
 
-    private IEnumerable<PublishedDocumentUrlSegment> ConvertToPersistedModel(PublishedDocumentUrlSegments model)
+    private static IEnumerable<PublishedDocumentUrlSegment> ConvertToPersistedModel(PublishedDocumentUrlSegments model)
     {
         foreach (PublishedDocumentUrlSegments.UrlSegment urlSegment in model.UrlSegments)
         {
@@ -816,7 +816,7 @@ public class DocumentUrlService : IDocumentUrlService
         return '/' + string.Join('/', urlSegments);
     }
 
-    private bool HideTopLevel(bool hideTopLevelNodeFromPath, bool isRootFirstItem, List<string> urlSegments)
+    private static bool HideTopLevel(bool hideTopLevelNodeFromPath, bool isRootFirstItem, List<string> urlSegments)
     {
         if (hideTopLevelNodeFromPath is false)
         {

src/Umbraco.Core/Services/EntityXmlSerializer.cs

@@ -13,7 +13,7 @@ namespace Umbraco.Cms.Core.Services;
 /// <summary>
 ///     Serializes entities to XML
 /// </summary>
-internal class EntityXmlSerializer : IEntityXmlSerializer
+internal sealed class EntityXmlSerializer : IEntityXmlSerializer
 {
     private readonly IConfigurationEditorJsonSerializer _configurationEditorJsonSerializer;
     private readonly IContentService _contentService;

src/Umbraco.Core/Services/FileSystem/PartialViewFolderService.cs

@@ -5,7 +5,7 @@ using Umbraco.Cms.Core.Services.OperationStatus;
 
 namespace Umbraco.Cms.Core.Services.FileSystem;
 
-internal class PartialViewFolderService : FolderServiceOperationBase<IPartialViewRepository, PartialViewFolderModel, PartialViewFolderOperationStatus>, IPartialViewFolderService
+internal sealed class PartialViewFolderService : FolderServiceOperationBase<IPartialViewRepository, PartialViewFolderModel, PartialViewFolderOperationStatus>, IPartialViewFolderService
 {
     public PartialViewFolderService(IPartialViewRepository repository, ICoreScopeProvider scopeProvider)
         : base(repository, scopeProvider)

src/Umbraco.Core/Services/FileSystem/ScriptFolderService.cs

@@ -5,7 +5,7 @@ using Umbraco.Cms.Core.Services.OperationStatus;
 
 namespace Umbraco.Cms.Core.Services.FileSystem;
 
-internal class ScriptFolderService : FolderServiceOperationBase<IScriptRepository, ScriptFolderModel, ScriptFolderOperationStatus>, IScriptFolderService
+internal sealed class ScriptFolderService : FolderServiceOperationBase<IScriptRepository, ScriptFolderModel, ScriptFolderOperationStatus>, IScriptFolderService
 {
     public ScriptFolderService(IScriptRepository repository, ICoreScopeProvider scopeProvider)
         : base(repository, scopeProvider)

src/Umbraco.Core/Services/FileSystem/StylesheetFolderService.cs

@@ -5,7 +5,7 @@ using Umbraco.Cms.Core.Services.OperationStatus;
 
 namespace Umbraco.Cms.Core.Services.FileSystem;
 
-internal class StylesheetFolderService : FolderServiceOperationBase<IStylesheetRepository, StylesheetFolderModel, StylesheetFolderOperationStatus>, IStylesheetFolderService
+internal sealed class StylesheetFolderService : FolderServiceOperationBase<IStylesheetRepository, StylesheetFolderModel, StylesheetFolderOperationStatus>, IStylesheetFolderService
 {
     public StylesheetFolderService(IStylesheetRepository repository, ICoreScopeProvider scopeProvider)
         : base(repository, scopeProvider)

src/Umbraco.Core/Services/IdKeyMap.cs

@@ -418,7 +418,7 @@ public class IdKeyMap : IIdKeyMap, IDisposable
 
     // ReSharper disable ClassNeverInstantiated.Local
     // ReSharper disable UnusedAutoPropertyAccessor.Local
-    private class TypedIdDto
+    private sealed class TypedIdDto
     {
         public int Id { get; set; }
 

src/Umbraco.Core/Services/KeyValueService.cs

@@ -4,7 +4,7 @@ using Umbraco.Cms.Core.Scoping;
 
 namespace Umbraco.Cms.Core.Services;
 
-internal class KeyValueService : IKeyValueService
+internal sealed class KeyValueService : IKeyValueService
 {
     private readonly IKeyValueRepository _repository;
     private readonly ICoreScopeProvider _scopeProvider;

src/Umbraco.Core/Services/MemberGroupService.cs

@@ -8,7 +8,7 @@ using Umbraco.Cms.Core.Services.OperationStatus;
 
 namespace Umbraco.Cms.Core.Services;
 
-internal class MemberGroupService : RepositoryService, IMemberGroupService
+internal sealed class MemberGroupService : RepositoryService, IMemberGroupService
 {
     private readonly IMemberGroupRepository _memberGroupRepository;
 

src/Umbraco.Core/Services/MemberTwoFactorLoginService.cs

@@ -6,7 +6,7 @@ using Umbraco.Cms.Core.Services.OperationStatus;
 namespace Umbraco.Cms.Core.Services;
 
 /// <inheritdoc cref="Umbraco.Cms.Core.Services.IMemberTwoFactorLoginService" />
-internal class MemberTwoFactorLoginService : TwoFactorLoginServiceBase, IMemberTwoFactorLoginService
+internal sealed class MemberTwoFactorLoginService : TwoFactorLoginServiceBase, IMemberTwoFactorLoginService
 {
     private readonly IMemberService _memberService;
 

src/Umbraco.Core/Services/NotificationService.cs

@@ -607,7 +607,7 @@ public class NotificationService : INotificationService
         }
     }
 
-    private class NotificationRequest
+    private sealed class NotificationRequest
     {
         public NotificationRequest(EmailMessage mail, string? action, string? userName, string? email)
         {

src/Umbraco.Core/Services/RedirectUrlService.cs

@@ -7,7 +7,7 @@ using Umbraco.Cms.Core.Scoping;
 
 namespace Umbraco.Cms.Core.Services;
 
-internal class RedirectUrlService : RepositoryService, IRedirectUrlService
+internal sealed class RedirectUrlService : RepositoryService, IRedirectUrlService
 {
     private readonly IRedirectUrlRepository _redirectUrlRepository;
 

src/Umbraco.Core/Services/UserTwoFactorLoginService.cs

@@ -7,7 +7,7 @@ using Umbraco.Cms.Core.Services.OperationStatus;
 namespace Umbraco.Cms.Core.Services;
 
 /// <inheritdoc cref="Umbraco.Cms.Core.Services.IUserTwoFactorLoginService" />
-internal class UserTwoFactorLoginService : TwoFactorLoginServiceBase, IUserTwoFactorLoginService
+internal sealed class UserTwoFactorLoginService : TwoFactorLoginServiceBase, IUserTwoFactorLoginService
 {
     private readonly IUserService _userService;
 

src/Umbraco.Core/Strings/Diff.cs

@@ -500,7 +500,7 @@ internal sealed class Diff
     /// <summary>
     ///     Data on one input file being compared.
     /// </summary>
-    internal class DiffData
+    internal sealed class DiffData
     {
         /// <summary>Buffer of numbers that will be compared.</summary>
         internal int[] Data;

src/Umbraco.Core/SystemLock.cs

@@ -89,7 +89,7 @@ public class SystemLock
 
     // note - before making those classes some structs, read
     // about "impure methods" and mutating readonly structs...
-    private class NamedSemaphoreReleaser : CriticalFinalizerObject, IDisposable
+    private sealed class NamedSemaphoreReleaser : CriticalFinalizerObject, IDisposable
     {
         private readonly Semaphore? _semaphore;
 
@@ -156,7 +156,7 @@ public class SystemLock
         }
     }
 
-    private class SemaphoreSlimReleaser : IDisposable
+    private sealed class SemaphoreSlimReleaser : IDisposable
     {
         private readonly SemaphoreSlim _semaphore;
 

src/Umbraco.Core/Telemetry/SiteIdentifierService.cs

@@ -6,7 +6,7 @@ using Umbraco.Cms.Core.Configuration.Models;
 namespace Umbraco.Cms.Core.Telemetry;
 
 /// <inheritdoc />
-internal class SiteIdentifierService : ISiteIdentifierService
+internal sealed class SiteIdentifierService : ISiteIdentifierService
 {
     private readonly IConfigManipulator _configManipulator;
     private readonly ILogger<SiteIdentifierService> _logger;

src/Umbraco.Core/Telemetry/TelemetryService.cs

@@ -11,7 +11,7 @@ using Umbraco.Extensions;
 namespace Umbraco.Cms.Core.Telemetry;
 
 /// <inheritdoc />
-internal class TelemetryService : ITelemetryService
+internal sealed class TelemetryService : ITelemetryService
 {
     private readonly IPackagingService _packagingService;
     private readonly IMetricsConsentService _metricsConsentService;

src/Umbraco.Core/UdiTypeConverter.cs

@@ -9,7 +9,7 @@ namespace Umbraco.Cms.Core;
 /// <remarks>
 ///     Primarily this is used so that WebApi can auto-bind a string parameter to a UDI instance
 /// </remarks>
-internal class UdiTypeConverter : TypeConverter
+internal sealed class UdiTypeConverter : TypeConverter
 {
     public override bool CanConvertFrom(ITypeDescriptorContext? context, Type sourceType)
     {

src/Umbraco.Core/Xml/XmlNodeListFactory.cs

@@ -13,7 +13,7 @@ public class XmlNodeListFactory
 
     #region XmlNodeListIterator
 
-    private class XmlNodeListIterator : XmlNodeList
+    private sealed class XmlNodeListIterator : XmlNodeList
     {
         private readonly XPathNodeIterator? _iterator;
         private readonly IList<XmlNode> _nodes = new List<XmlNode>();
@@ -108,7 +108,7 @@ public class XmlNodeListFactory
 
         #region XmlNodeListEnumerator
 
-        private class XmlNodeListEnumerator : IEnumerator
+        private sealed class XmlNodeListEnumerator : IEnumerator
         {
             private readonly XmlNodeListIterator _iterator;
             private int _position = -1;

src/Umbraco.Infrastructure/BackgroundJobs/RecurringBackgroundJobHostedServiceRunner.cs

@@ -71,7 +71,7 @@ public class RecurringBackgroundJobHostedServiceRunner : IHostedService
         _logger.LogInformation("Completed stopping recurring background jobs hosted services");
     }
 
-    private class NamedServiceJob
+    private sealed class NamedServiceJob
     {
         public NamedServiceJob(string name, IHostedService hostedService)
         {

src/Umbraco.Infrastructure/Cache/FullDataSetRepositoryCachePolicy.cs

@@ -21,7 +21,7 @@ namespace Umbraco.Cms.Core.Cache;
 ///         keep as a whole in memory.
 ///     </para>
 /// </remarks>
-internal class FullDataSetRepositoryCachePolicy<TEntity, TId> : RepositoryCachePolicyBase<TEntity, TId>
+internal sealed class FullDataSetRepositoryCachePolicy<TEntity, TId> : RepositoryCachePolicyBase<TEntity, TId>
     where TEntity : class, IEntity
 {
     protected static readonly TId[] EmptyIds = new TId[0]; // const

src/Umbraco.Infrastructure/Cache/SingleItemsOnlyRepositoryCachePolicy.cs

@@ -18,7 +18,7 @@ namespace Umbraco.Cms.Core.Cache;
 ///     </para>
 ///     <para>Used by DictionaryRepository.</para>
 /// </remarks>
-internal class SingleItemsOnlyRepositoryCachePolicy<TEntity, TId> : DefaultRepositoryCachePolicy<TEntity, TId>
+internal sealed class SingleItemsOnlyRepositoryCachePolicy<TEntity, TId> : DefaultRepositoryCachePolicy<TEntity, TId>
     where TEntity : class, IEntity
 {
     public SingleItemsOnlyRepositoryCachePolicy(IAppPolicyCache cache, IScopeAccessor scopeAccessor, RepositoryCachePolicyOptions options)

src/Umbraco.Infrastructure/Configuration/JsonConfigManipulator.cs

@@ -10,7 +10,7 @@ using Umbraco.Cms.Core.Configuration.Models;
 
 namespace Umbraco.Cms.Infrastructure.Configuration;
 
-internal class JsonConfigManipulator : IConfigManipulator
+internal sealed class JsonConfigManipulator : IConfigManipulator
 {
     private const string ConnectionStringObjectName = "ConnectionStrings";
     private const string UmbracoConnectionStringPath = $"{ConnectionStringObjectName}:{Constants.System.UmbracoConnectionName}";

src/Umbraco.Infrastructure/Examine/Deferred/DeliveryApiContentIndexHandleContentChanges.cs

@@ -136,7 +136,7 @@ internal sealed class DeliveryApiContentIndexHandleContentChanges : DeliveryApiC
                 }
             });
 
-    private class CulturePublishStatus : IEquatable<CulturePublishStatus>
+    private sealed class CulturePublishStatus : IEquatable<CulturePublishStatus>
     {
         public required string Culture { get; set; }
 

src/Umbraco.Infrastructure/Examine/DeferredActions.cs

@@ -2,7 +2,7 @@ using Umbraco.Cms.Core.Scoping;
 
 namespace Umbraco.Cms.Infrastructure.Examine;
 
-internal class DeferredActions
+internal sealed class DeferredActions
 {
     // the default enlist priority is 100
     // enlist with a lower priority to ensure that anything "default" runs after us

src/Umbraco.Infrastructure/Examine/ExamineIndexingMainDomHandler.cs

@@ -5,7 +5,7 @@ using Umbraco.Cms.Core.Runtime;
 
 namespace Umbraco.Cms.Infrastructure.Examine;
 
-internal class ExamineIndexingMainDomHandler
+internal sealed class ExamineIndexingMainDomHandler
 {
     private readonly IMainDom _mainDom;
     private readonly IProfilingLogger _profilingLogger;

src/Umbraco.Infrastructure/Examine/ExamineUmbracoIndexingHandler.cs

@@ -14,7 +14,7 @@ namespace Umbraco.Cms.Infrastructure.Examine;
 /// <summary>
 ///     Indexing handler for Examine indexes
 /// </summary>
-internal class ExamineUmbracoIndexingHandler : IUmbracoIndexingHandler
+internal sealed class ExamineUmbracoIndexingHandler : IUmbracoIndexingHandler
 {
     private readonly IBackgroundTaskQueue _backgroundTaskQueue;
     private readonly IContentValueSetBuilder _contentValueSetBuilder;
@@ -208,7 +208,7 @@ internal class ExamineUmbracoIndexingHandler : IUmbracoIndexingHandler
     /// <summary>
     ///     Re-indexes an <see cref="IContent" /> item on a background thread
     /// </summary>
-    private class DeferredReIndexForContent : IDeferredAction
+    private sealed class DeferredReIndexForContent : IDeferredAction
     {
         private readonly IBackgroundTaskQueue _backgroundTaskQueue;
         private readonly IContent _content;
@@ -271,7 +271,7 @@ internal class ExamineUmbracoIndexingHandler : IUmbracoIndexingHandler
     /// <summary>
     ///     Re-indexes an <see cref="IMedia" /> item on a background thread
     /// </summary>
-    private class DeferredReIndexForMedia : IDeferredAction
+    private sealed class DeferredReIndexForMedia : IDeferredAction
     {
         private readonly IBackgroundTaskQueue _backgroundTaskQueue;
         private readonly ExamineUmbracoIndexingHandler _examineUmbracoIndexingHandler;
@@ -323,7 +323,7 @@ internal class ExamineUmbracoIndexingHandler : IUmbracoIndexingHandler
     /// <summary>
     ///     Re-indexes an <see cref="IMember" /> item on a background thread
     /// </summary>
-    private class DeferredReIndexForMember : IDeferredAction
+    private sealed class DeferredReIndexForMember : IDeferredAction
     {
         private readonly IBackgroundTaskQueue _backgroundTaskQueue;
         private readonly ExamineUmbracoIndexingHandler _examineUmbracoIndexingHandler;
@@ -366,7 +366,7 @@ internal class ExamineUmbracoIndexingHandler : IUmbracoIndexingHandler
             });
     }
 
-    private class DeferredDeleteIndex : IDeferredAction
+    private sealed class DeferredDeleteIndex : IDeferredAction
     {
         private readonly ExamineUmbracoIndexingHandler _examineUmbracoIndexingHandler;
         private readonly int _id;
@@ -435,7 +435,7 @@ internal class ExamineUmbracoIndexingHandler : IUmbracoIndexingHandler
     /// <summary>
     ///     Removes all protected content from applicable indexes on a background thread
     /// </summary>
-    private class DeferredRemoveProtectedContent : IDeferredAction
+    private sealed class DeferredRemoveProtectedContent : IDeferredAction
     {
         private readonly IBackgroundTaskQueue _backgroundTaskQueue;
         private readonly ExamineUmbracoIndexingHandler _examineUmbracoIndexingHandler;

src/Umbraco.Infrastructure/Logging/Serilog/Enrichers/Log4NetLevelMapperEnricher.cs

@@ -7,7 +7,7 @@ namespace Umbraco.Cms.Core.Logging.Serilog.Enrichers;
 ///     This is used to create a new property in Logs called 'Log4NetLevel'
 ///     So that we can map Serilog levels to Log4Net levels - so log files stay consistent
 /// </summary>
-internal class Log4NetLevelMapperEnricher : ILogEventEnricher
+internal sealed class Log4NetLevelMapperEnricher : ILogEventEnricher
 {
     public void Enrich(LogEvent logEvent, ILogEventPropertyFactory propertyFactory)
     {

src/Umbraco.Infrastructure/Logging/Viewer/CountingFilter.cs

@@ -2,7 +2,7 @@ using Serilog.Events;
 
 namespace Umbraco.Cms.Core.Logging.Viewer;
 
-internal class CountingFilter : ILogFilter
+internal sealed class CountingFilter : ILogFilter
 {
     public CountingFilter() => Counts = new LogLevelCounts();
 

src/Umbraco.Infrastructure/Logging/Viewer/ErrorCounterFilter.cs

@@ -2,7 +2,7 @@ using Serilog.Events;
 
 namespace Umbraco.Cms.Core.Logging.Viewer;
 
-internal class ErrorCounterFilter : ILogFilter
+internal sealed class ErrorCounterFilter : ILogFilter
 {
     public int Count { get; private set; }
 

src/Umbraco.Infrastructure/Logging/Viewer/ExpressionFilter.cs

@@ -6,7 +6,7 @@ using Umbraco.Extensions;
 namespace Umbraco.Cms.Core.Logging.Viewer;
 
 // Log Expression Filters (pass in filter exp string)
-internal class ExpressionFilter : ILogFilter
+internal sealed class ExpressionFilter : ILogFilter
 {
     private const string ExpressionOperators = "()+=*<>%-";
     private readonly Func<LogEvent, bool>? _filter;
@@ -57,7 +57,7 @@ internal class ExpressionFilter : ILogFilter
 
     public bool TakeLogEvent(LogEvent e) => _filter == null || _filter(e);
 
-    private Func<LogEvent, bool>? PerformMessageLikeFilter(string filterExpression, SerilogLegacyNameResolver serilogLegacyNameResolver)
+    private static Func<LogEvent, bool>? PerformMessageLikeFilter(string filterExpression, SerilogLegacyNameResolver serilogLegacyNameResolver)
     {
         var filterSearch = $"@Message like '%{SerilogExpression.EscapeLikeExpressionContent(filterExpression)}%'";
         if (SerilogExpression.TryCompile(filterSearch, null, serilogLegacyNameResolver, out CompiledExpression? compiled, out var error))

src/Umbraco.Infrastructure/Logging/Viewer/MessageTemplateFilter.cs

@@ -2,7 +2,7 @@ using Serilog.Events;
 
 namespace Umbraco.Cms.Core.Logging.Viewer;
 
-internal class MessageTemplateFilter : ILogFilter
+internal sealed class MessageTemplateFilter : ILogFilter
 {
     public readonly Dictionary<string, int> Counts = new();
 

src/Umbraco.Infrastructure/Logging/Viewer/SerilogJsonLogViewer.cs

@@ -5,7 +5,7 @@ using ILogger = Serilog.ILogger;
 
 namespace Umbraco.Cms.Core.Logging.Viewer;
 
-internal class SerilogJsonLogViewer : SerilogLogViewerSourceBase
+internal sealed class SerilogJsonLogViewer : SerilogLogViewerSourceBase
 {
     private const int FileSizeCap = 100;
     private readonly ILogger<SerilogJsonLogViewer> _logger;
@@ -112,7 +112,7 @@ internal class SerilogJsonLogViewer : SerilogLogViewerSourceBase
         return logs;
     }
 
-    private string GetSearchPattern(DateTime day) => $"*{day:yyyyMMdd}*.json";
+    private static string GetSearchPattern(DateTime day) => $"*{day:yyyyMMdd}*.json";
 
     private bool TryRead(LogEventReader reader, out LogEvent? evt)
     {

src/Umbraco.Infrastructure/Migrations/Install/DatabaseDataCreator.cs

@@ -17,7 +17,7 @@ namespace Umbraco.Cms.Infrastructure.Migrations.Install;
 /// <summary>
 ///     Creates the initial database data during install.
 /// </summary>
-internal class DatabaseDataCreator
+internal sealed class DatabaseDataCreator
 {
 
     internal const string EditorGroupAlias = "editor";

src/Umbraco.Infrastructure/Migrations/MigrationContext.cs

@@ -8,10 +8,9 @@ namespace Umbraco.Cms.Infrastructure.Migrations;
 /// <summary>
 ///     Implements <see cref="IMigrationContext" />.
 /// </summary>
-internal class MigrationContext : IMigrationContext
+internal sealed class MigrationContext : IMigrationContext
 {
     private readonly Action? _onCompleteAction;
-    private readonly List<Type> _postMigrations = new();
 
     /// <summary>
     ///     Initializes a new instance of the <see cref="MigrationContext" /> class.