diff --git a/OnTopic.Editor.AspNetCore.Host/OnTopic.Editor.AspNetCore.Host.csproj b/OnTopic.Editor.AspNetCore.Host/OnTopic.Editor.AspNetCore.Host.csproj
index 4255a40a..d37ffd19 100644
--- a/OnTopic.Editor.AspNetCore.Host/OnTopic.Editor.AspNetCore.Host.csproj
+++ b/OnTopic.Editor.AspNetCore.Host/OnTopic.Editor.AspNetCore.Host.csproj
@@ -2,16 +2,21 @@
 
   <PropertyGroup>
     <TargetFramework>netcoreapp3.1</TargetFramework>
+    <LangVersion>9.0</LangVersion>
     <AspNetCoreHostingModel>InProcess</AspNetCoreHostingModel>
     <UserSecretsId>aff0d52c-eab2-4c07-88b2-5af34649f874</UserSecretsId>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="OnTopic" Version="4.5.0" />
-    <PackageReference Include="OnTopic.ViewModels" Version="4.5.0" />
-    <PackageReference Include="OnTopic.AspNetCore.Mvc" Version="4.5.0" />
-    <PackageReference Include="OnTopic.Data.Caching" Version="4.5.0" />
-    <PackageReference Include="OnTopic.Data.Sql" Version="4.5.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="3.3.1">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+    <PackageReference Include="OnTopic" Version="4.6.0" />
+    <PackageReference Include="OnTopic.ViewModels" Version="4.6.0" />
+    <PackageReference Include="OnTopic.AspNetCore.Mvc" Version="4.6.0" />
+    <PackageReference Include="OnTopic.Data.Caching" Version="4.6.0" />
+    <PackageReference Include="OnTopic.Data.Sql" Version="4.6.0" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation" Version="3.1.8" />
   </ItemGroup>
 
diff --git a/OnTopic.Editor.AspNetCore.Host/SampleActivator.cs b/OnTopic.Editor.AspNetCore.Host/SampleActivator.cs
index 963d2ccb..4b92c919 100644
--- a/OnTopic.Editor.AspNetCore.Host/SampleActivator.cs
+++ b/OnTopic.Editor.AspNetCore.Host/SampleActivator.cs
@@ -88,6 +88,11 @@ public SampleActivator(string connectionString, IWebHostEnvironment webHostEnvir
     /// <returns>A concrete instance of an <see cref="IController"/>.</returns>
     public object Create(ControllerContext context) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(context, nameof(context));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Determine controller type
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -111,6 +116,11 @@ public object Create(ControllerContext context) {
     /// <returns>A concrete instance of an <see cref="IController"/>.</returns>
     public object Create(ViewComponentContext context) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(context, nameof(context));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Determine view component type
       \-----------------------------------------------------------------------------------------------------------------------*/
diff --git a/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Editor/Components/ContentTypeList/Default.cshtml b/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Editor/Components/ContentTypeList/Default.cshtml
index 4b8eeb59..e25f7752 100644
--- a/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Editor/Components/ContentTypeList/Default.cshtml
+++ b/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Editor/Components/ContentTypeList/Default.cshtml
@@ -1,6 +1,6 @@
 @model ContentTypeListViewModel
 
-@if (Model.TopicList.Count == 1) {
+@if (Model.TopicList.Count is 1) {
   <!-- New topics are not permitted in this context -->
 }
 
@@ -20,7 +20,9 @@ else if (Model.TopicList.Count > 2) {
           var option = $('option:selected', this);
           @if (Model.EnableModal?? false) {
             <text>
-              initEditorModal('@Model.AttributeKey', option.text(), option.val(), @Model.OnModalClose); return false;
+              initEditorModal('@Model.AttributeKey', option.text(), option.val(), @Model.OnModalClose);
+              $(this).prop('selectedIndex', 0);
+              return false;
             </text>
           }
           else {
@@ -37,7 +39,7 @@ else if (Model.TopicList.Count > 2) {
 
 else {
   <div class="ChildTopic">
-    @if (Model.EnableModal == true) {
+    @if (Model.EnableModal is true) {
       <a onclick="initEditorModal('@Model.AttributeKey', '@Model.TopicList.LastOrDefault().Text', '@Model.TopicList.LastOrDefault().Value', @Model.OnModalClose); return false;" class="btn btn-info btn-sm">
         <span class="fa fa-plus"></span>
         @Model.TopicList.LastOrDefault().Text
diff --git a/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Editor/Edit.cshtml b/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Editor/Edit.cshtml
index 542829f2..79a2a4b0 100644
--- a/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Editor/Edit.cshtml
+++ b/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Editor/Edit.cshtml
@@ -20,7 +20,7 @@
   <div id="FormArea" class="row form area">
 
     <div class="col-md-12">
-      @if (Model.ContentTypeDescriptor.DisableDelete) {
+      @if (Model.ContentTypeDescriptor.DisableDelete && !Model.IsNew) {
         <div class="alert alert-warning" role="alert">
           <button type="button" class="close" data-dismiss="alert"><span aria-hidden="true">×</span><span class="sr-only">Close</span></button>
           <strong>Warning:</strong> This topic is part of the OnTopic internal organizational structure and is not intended to be modified. Deletion of this Topic has been disabled.
@@ -31,7 +31,7 @@
           @Model.ContentTypeDescriptor.Description
         </div>
       }
-      @if (Model.Topic.DerivedTopic != null) {
+      @if (Model.Topic.DerivedTopic is not null) {
         <div class="alert alert-primary" role="alert">
           <strong>Note:</strong> This topic derives from <a href="@Url.Action("Edit", new { path = Model.Topic.DerivedTopic.WebPath })">@Model.Topic.DerivedTopic.Title</a>. Any values not explicitly defined here will be inherited from that topic.
         </div>
@@ -46,7 +46,7 @@
 
           var displayGroupId = displayGroupName.Replace(" ", String.Empty);
 
-          <div id="Group_@displayGroupId" class="tab-pane fade@(index == 0 ? " show active" : "")" role="tabpanel" aria-labelledby="Tab_@displayGroupId">
+          <div id="Group_@displayGroupId" class="tab-pane fade@(index is 0 ? " show active" : "")" role="tabpanel" aria-labelledby="Tab_@displayGroupId">
             <section id="Section_@displayGroupId">
 
               @foreach (var attribute in Model.ContentTypeDescriptor.GetAttributeDescriptors(displayGroupName)) {
@@ -105,7 +105,7 @@
     }
   });
 
-  @if (Model.Topic.DerivedTopic != null) {
+  @if (Model.Topic.DerivedTopic is not null) {
     <text>
       /**
       * Disable required fields if derived topic, as missing values will be inherited
diff --git a/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Shared/_Toolbar.cshtml b/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Shared/_Toolbar.cshtml
index d0944732..7f7adce5 100644
--- a/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Shared/_Toolbar.cshtml
+++ b/OnTopic.Editor.AspNetCore/Areas/Editor/Views/Shared/_Toolbar.cshtml
@@ -11,13 +11,13 @@
 
     @if (Model.Topic.VersionHistory.Count > 1) {
       <!-- Versions -->
-      <div id="VersionsDropdown" class="dropdown d-none d-lg-inline-block" style="display:inline-block;">
+      <div id="VersionsDropdown" class="dropdown d-none d-md-inline-block" style="display:inline-block;">
         <button class="btn btn-sm btn-ancillary dropdown-toggle" type="button" id="VersionsButton" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
           <span class="fa fa-history"></span>
           Versions
           <span class="caret"></span>
         </button>
-        <ul class="dropdown-menu" role="menu" aria-labelledby="VersionsButton" style="left: 3px; top: 98%;">
+        <ul class="dropdown-menu" role="menu" aria-labelledby="VersionsButton">
           @foreach (DateTime version in Model.Topic.VersionHistory) {
             <li role="presentation" class="small">
               <a tabindex="-1" role="menuitem" href="@Url.Action("SetVersion", "Editor", new { path=Model.Topic.WebPath, version=version.ToString("MM/dd/yyyy hh:mm:ss.fff tt"), isModal=Model.IsModal })">@version.ToString()</a>
@@ -64,7 +64,7 @@
       var displayGroupName      = displayGroups[i];
       var displayGroupId        = displayGroups[i].Replace(" ", String.Empty);
       <li class="nav-item">
-        <a id="Tab_@displayGroupId" class="nav-link @(i == 0 ? "active" : "")" href="#Group_@displayGroupId" data-toggle="tab" role="tab" aria-controls="#Group_@displayGroupId" aria-expanded="@(i == 0 ? "true" : "false")">@displayGroupName</a>
+        <a id="Tab_@displayGroupId" class="nav-link @(i is 0 ? "active" : "")" href="#Group_@displayGroupId" data-toggle="tab" role="tab" aria-controls="#Group_@displayGroupId" aria-expanded="@(i is 0 ? "true" : "false")">@displayGroupName</a>
       </li>
     }
   </ul>
diff --git a/OnTopic.Editor.AspNetCore/Components/ContentTypeListViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/ContentTypeListViewComponent.cs
index 7b1a80bc..7ae36f41 100644
--- a/OnTopic.Editor.AspNetCore/Components/ContentTypeListViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/ContentTypeListViewComponent.cs
@@ -12,6 +12,7 @@
 using OnTopic.Editor.AspNetCore.Models;
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 using OnTopic.Repositories;
 
 namespace OnTopic.Editor.AspNetCore.Components {
@@ -58,6 +59,11 @@ public IViewComponentResult Invoke(
       string onModalClose = null
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Establish view model
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -72,7 +78,7 @@ public IViewComponentResult Invoke(
       | Set label
       \-----------------------------------------------------------------------------------------------------------------------*/
       viewModel.TopicList.Add(
-        new SelectListItem {
+        new() {
           Value = null,
           Text = "Add a child topic…"
         }
@@ -83,7 +89,7 @@ public IViewComponentResult Invoke(
       \-----------------------------------------------------------------------------------------------------------------------*/
       foreach (var contentType in values.OrderBy(c => c.Title)) {
         viewModel.TopicList.Add(
-          new SelectListItem {
+          new() {
             Value               = getValue(contentType.Key),
             Text                = contentType.Title
           }
@@ -94,13 +100,14 @@ public IViewComponentResult Invoke(
       | Get content type
       >-------------------------------------------------------------------------------------------------------------------------
       | If the database is uninitialized, the content type won't be found. In that case, return an empty view, which will
-      | effectively hide the component.
+      | effectively hide the component. If the topic cannot be found, assume it is a new topic and attempt to load the parent
+      | for context.
       \-----------------------------------------------------------------------------------------------------------------------*/
       var contentTypes          = _topicRepository.GetContentTypeDescriptors();
-      var actualTopic           = _topicRepository.Load(currentTopic.Id);
+      var actualTopic           = _topicRepository.Load(currentTopic.Id)?? _topicRepository.Load(currentTopic.Parent.Id);
       var actualContentType     = contentTypes.GetTopic(currentTopic.ContentType);
 
-      if (actualContentType == null) {
+      if (actualContentType is null || actualTopic is null) {
         return View(viewModel);
       }
 
@@ -118,7 +125,7 @@ public IViewComponentResult Invoke(
             .Relationships
             .GetTopics("ContentTypes")
             .Select(c =>
-              new SelectListItem {
+              new SelectListItem() {
                 Value           = getValue(c.Key),
                 Text            = c.Title
               }
@@ -136,7 +143,7 @@ public IViewComponentResult Invoke(
       | content types explicitly annotated as "implicitly permitted", and which are not marked as hidden are displayed. This
       | typically include the Page content type, and popular derivatives of it, such as Content List.
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (viewModel.TopicList.Count.Equals(1) && !actualContentType.DisableChildTopics) {
+      if (viewModel.TopicList.Count is 1 && !actualContentType.DisableChildTopics) {
         viewModel.TopicList.AddRange(
           contentTypes
             .Where(c => actualContentType.Equals("Container") || c.Attributes.GetBoolean("ImplicitlyPermitted", false))
diff --git a/OnTopic.Editor.AspNetCore/Components/DateTimeViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/DateTimeViewComponent.cs
index d51eda54..a2df4a8b 100644
--- a/OnTopic.Editor.AspNetCore/Components/DateTimeViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/DateTimeViewComponent.cs
@@ -7,6 +7,7 @@
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Components.ViewModels;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 
 namespace OnTopic.Editor.AspNetCore.Components {
 
@@ -39,6 +40,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
diff --git a/OnTopic.Editor.AspNetCore/Components/FileListViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/FileListViewComponent.cs
index a0b386dc..3294ef2c 100644
--- a/OnTopic.Editor.AspNetCore/Components/FileListViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/FileListViewComponent.cs
@@ -12,6 +12,7 @@
 using OnTopic.Editor.AspNetCore.Models;
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 
 #nullable enable
 
@@ -52,6 +53,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -73,7 +80,7 @@ string htmlFieldPrefix
       /*------------------------------------------------------------------------------------------------------------------------
       | Set model values
       \-----------------------------------------------------------------------------------------------------------------------*/
-      model.Files               = GetFiles(model.InheritedValue, attribute, model.AbsolutePath);
+      model.Files.AddRange(GetFiles(model.InheritedValue, attribute, model.AbsolutePath));
       model.AbsolutePath        = _webHostEnvironment.ContentRootPath + attribute.Path;
 
       /*------------------------------------------------------------------------------------------------------------------------
@@ -95,6 +102,11 @@ public static List<SelectListItem> GetFiles(
       string absolutePath
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | INSTANTIATE OBJECTS
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -111,14 +123,14 @@ string absolutePath
       /*------------------------------------------------------------------------------------------------------------------------
       | Filter file list based on extension
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (attribute.Extension != null) {
+      if (attribute.Extension is not null) {
         searchPattern = searchPattern + "." + attribute.Extension;
       }
 
       /*------------------------------------------------------------------------------------------------------------------------
       | Filter file list based on filter criteria
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (attribute.Filter != null) {
+      if (attribute.Filter is not null) {
         searchPattern = attribute.Filter + searchPattern;
       }
 
@@ -128,12 +140,12 @@ string absolutePath
       var foundFiles = Directory.GetFiles(absolutePath, searchPattern, searchOption);
 
       if (!String.IsNullOrEmpty(inheritedValue)) {
-        files.Add(new SelectListItem("", inheritedValue));
+        files.Add(new("", inheritedValue));
       }
       foreach (var foundFile in foundFiles) {
         var fileName = foundFile.Replace(absolutePath, "");
         var fileNameKey = fileName.Replace("." + attribute.Extension, "");
-        files.Add(new SelectListItem(fileNameKey, fileName));
+        files.Add(new(fileNameKey, fileName));
       }
 
       /*------------------------------------------------------------------------------------------------------------------------
diff --git a/OnTopic.Editor.AspNetCore/Components/FilePathViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/FilePathViewComponent.cs
index edfaf706..1407e895 100644
--- a/OnTopic.Editor.AspNetCore/Components/FilePathViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/FilePathViewComponent.cs
@@ -28,7 +28,7 @@ public class FilePathViewComponent: ViewComponent {
     /*==========================================================================================================================
     | PRIVATE VARIABLES
     \-------------------------------------------------------------------------------------------------------------------------*/
-    private                     Topic?                          _currentTopic                   = null;
+    private                     Topic?                          _currentTopic;
 
     /*==========================================================================================================================
     | CONSTRUCTOR
@@ -71,7 +71,7 @@ public FilePathViewComponent(ITopicRepository topicRepository) : base() {
     /// <returns>The Topic associated with the current request.</returns>
     protected Topic? CurrentTopic {
       get {
-        if (_currentTopic == null) {
+        if (_currentTopic is null) {
           _currentTopic = TopicRepository.Load(RouteData);
         }
         Contract.Assume(_currentTopic, nameof(_currentTopic));
@@ -91,6 +91,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -133,10 +139,10 @@ public string GetInheritedValue(string attributeKey, FilePathAttributeTopicViewM
 
       var inheritedValue                      = "";
 
-      if (attribute.InheritValue == true && attribute.RelativeToTopicPath == true) {
+      if (attribute is { InheritValue: true, RelativeToTopicPath: true }) {
         inheritedValue                        = GetPath(attributeKey, attribute);
       }
-      else if (attribute.InheritValue == true) {
+      else if (attribute is { InheritValue: true }) {
         inheritedValue                        = CurrentTopic?.Attributes.GetValue(attributeKey, true)?? "";
       }
 
@@ -158,6 +164,11 @@ public string GetInheritedValue(string attributeKey, FilePathAttributeTopicViewM
     /// <returns>A constructed file path.</returns>
     public string GetPath(string attributeKey, FilePathAttributeTopicViewModel options) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(options, nameof(options));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Build configured file path string base on values and settings parameters passed to the method
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -170,14 +181,14 @@ public string GetPath(string attributeKey, FilePathAttributeTopicViewModel optio
       /*------------------------------------------------------------------------------------------------------------------------
       | Only process the path if both topic and attribtueKey are provided
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (startTopic is null || attributeKey is null || attributeKey.Length.Equals(0)) return "";
+      if (startTopic is null || attributeKey is null or { Length: 0 }) return "";
 
       /*------------------------------------------------------------------------------------------------------------------------
       | Crawl up the topics tree to find file path values set at a higher level
       \-----------------------------------------------------------------------------------------------------------------------*/
-      while (String.IsNullOrEmpty(filePath) && startTopic != null && startTopic.Parent != null) {
+      while (String.IsNullOrEmpty(filePath) && startTopic is not null && startTopic.Parent is not null) {
         startTopic                      = startTopic.Parent;
-        if (startTopic != null && !String.IsNullOrEmpty(attributeKey)) {
+        if (startTopic is not null && !String.IsNullOrEmpty(attributeKey)) {
           filePath                      = startTopic.Attributes.GetValue(attributeKey);
         }
       }
@@ -185,14 +196,14 @@ public string GetPath(string attributeKey, FilePathAttributeTopicViewModel optio
       /*------------------------------------------------------------------------------------------------------------------------
       | Add topic keys (directory names) between the start topic and the end topic based on the topic's WebPath property
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (startTopic != null) {
+      if (startTopic is not null) {
         if (startTopic.GetWebPath().Length > endTopic?.GetWebPath().Length) {
           throw new InvalidOperationException(
             $"The path of {startTopic.GetWebPath()} should be shorter than the length of {endTopic.GetWebPath()}."
           );
         }
         var startTopicWebPath           = startTopic.GetWebPath().Replace("/Root/", "/");
-        relativePath                    = endTopic?.GetWebPath().Substring(Math.Max(startTopicWebPath.Length-1,0));
+        relativePath                    = endTopic?.GetWebPath()[Math.Max(startTopicWebPath.Length-1, 0)..];
       }
 
       /*------------------------------------------------------------------------------------------------------------------------
@@ -215,7 +226,7 @@ public string GetPath(string attributeKey, FilePathAttributeTopicViewModel optio
       /*------------------------------------------------------------------------------------------------------------------------
       | Replace path slashes with backslashes if the resulting file path value uses a UNC or basic file path format
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (filePath.IndexOf("\\", StringComparison.InvariantCulture) >= 0) {
+      if (filePath.Contains("\\", StringComparison.InvariantCulture)) {
         filePath                        = filePath.Replace("/", "\\");
       }
 
diff --git a/OnTopic.Editor.AspNetCore/Components/HtmlViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/HtmlViewComponent.cs
index 885e80a5..a777b4cc 100644
--- a/OnTopic.Editor.AspNetCore/Components/HtmlViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/HtmlViewComponent.cs
@@ -6,6 +6,7 @@
 using Microsoft.AspNetCore.Mvc;
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 
 namespace OnTopic.Editor.AspNetCore.Components {
 
@@ -37,6 +38,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -50,7 +57,7 @@ string htmlFieldPrefix
       attribute.Height          ??= attribute.GetIntegerConfigurationValue(     "Height",               0);
       attribute.CssClass        ??= attribute.GetConfigurationValue(            "CssClass",             "FormField Field");
 
-      if (attribute.Height == null || attribute.Height == 0 && attribute.Rows != null) {
+      if (attribute.Height is null || attribute.Height is 0 && attribute.Rows is not null) {
         attribute.Height = attribute.Rows * 20;
       }
 
diff --git a/OnTopic.Editor.AspNetCore/Components/IncomingRelationshipViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/IncomingRelationshipViewComponent.cs
index 8cb29e93..5ddbc035 100644
--- a/OnTopic.Editor.AspNetCore/Components/IncomingRelationshipViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/IncomingRelationshipViewComponent.cs
@@ -8,6 +8,7 @@
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Components.ViewModels;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 using OnTopic.Repositories;
 using OnTopic.ViewModels;
 
@@ -48,6 +49,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
diff --git a/OnTopic.Editor.AspNetCore/Components/LastModifiedByViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/LastModifiedByViewComponent.cs
index 800867b7..b6b7cf64 100644
--- a/OnTopic.Editor.AspNetCore/Components/LastModifiedByViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/LastModifiedByViewComponent.cs
@@ -7,6 +7,7 @@
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Components.ViewModels;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 
 namespace OnTopic.Editor.AspNetCore.Components {
 
@@ -38,6 +39,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
diff --git a/OnTopic.Editor.AspNetCore/Components/LastModifiedViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/LastModifiedViewComponent.cs
index ec79c4c3..285bdced 100644
--- a/OnTopic.Editor.AspNetCore/Components/LastModifiedViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/LastModifiedViewComponent.cs
@@ -4,10 +4,12 @@
 | Project       Topics Library
 \=============================================================================================================================*/
 using System;
+using System.Globalization;
 using Microsoft.AspNetCore.Mvc;
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Components.ViewModels;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 
 namespace OnTopic.Editor.AspNetCore.Components {
 
@@ -40,6 +42,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -53,13 +61,13 @@ string htmlFieldPrefix
       /*------------------------------------------------------------------------------------------------------------------------
       | Set model values
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (currentTopic.LastModified != null && currentTopic.LastModified != DateTime.MinValue) {
-        model.CurrentValue      = currentTopic.LastModified.ToString();
+      if (currentTopic.LastModified != DateTime.MinValue) {
+        model.CurrentValue      = currentTopic.LastModified.ToString(CultureInfo.InvariantCulture);
       }
       else {
         model.CurrentValue      = model.Value;
       }
-      model.Value               = DateTime.Now.ToString();
+      model.Value               = DateTime.Now.ToString(CultureInfo.InvariantCulture);
 
       /*------------------------------------------------------------------------------------------------------------------------
       | Return view with view model
diff --git a/OnTopic.Editor.AspNetCore/Components/NestedTopicListViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/NestedTopicListViewComponent.cs
index 6003205e..9c6adb5f 100644
--- a/OnTopic.Editor.AspNetCore/Components/NestedTopicListViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/NestedTopicListViewComponent.cs
@@ -9,6 +9,7 @@
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Components.ViewModels;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 using OnTopic.Repositories;
 
 namespace OnTopic.Editor.AspNetCore.Components {
@@ -48,6 +49,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
diff --git a/OnTopic.Editor.AspNetCore/Components/RelationshipViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/RelationshipViewComponent.cs
index 3289b3da..43a49032 100644
--- a/OnTopic.Editor.AspNetCore/Components/RelationshipViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/RelationshipViewComponent.cs
@@ -7,6 +7,7 @@
 using Microsoft.AspNetCore.Mvc;
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 
 namespace OnTopic.Editor.AspNetCore.Components {
 
@@ -38,6 +39,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
diff --git a/OnTopic.Editor.AspNetCore/Components/TextAreaViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/TextAreaViewComponent.cs
index 69faccce..c20cdcc7 100644
--- a/OnTopic.Editor.AspNetCore/Components/TextAreaViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/TextAreaViewComponent.cs
@@ -7,6 +7,7 @@
 using Microsoft.AspNetCore.Mvc;
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 
 namespace OnTopic.Editor.AspNetCore.Components {
 
@@ -39,6 +40,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
diff --git a/OnTopic.Editor.AspNetCore/Components/TextViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/TextViewComponent.cs
index dffbcf4d..9ff496fa 100644
--- a/OnTopic.Editor.AspNetCore/Components/TextViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/TextViewComponent.cs
@@ -7,6 +7,7 @@
 using Microsoft.AspNetCore.Mvc;
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 
 namespace OnTopic.Editor.AspNetCore.Components {
 
@@ -39,6 +40,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
diff --git a/OnTopic.Editor.AspNetCore/Components/TokenizedTopicListViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/TokenizedTopicListViewComponent.cs
index 3e76326a..a3436e02 100644
--- a/OnTopic.Editor.AspNetCore/Components/TokenizedTopicListViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/TokenizedTopicListViewComponent.cs
@@ -4,10 +4,12 @@
 | Project       Topics Library
 \=============================================================================================================================*/
 using System;
+using System.Globalization;
 using Microsoft.AspNetCore.Mvc;
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Components.ViewModels;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 using OnTopic.Repositories;
 
 namespace OnTopic.Editor.AspNetCore.Components {
@@ -47,6 +49,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -118,12 +126,12 @@ private string GetTopicJson(string topicId) {
     | Set initial variables
     \---------------------------------------------------------------------------------------------------------------------------*/
       var topicJson               = "";
-      var topic                   = _topicRepository.Load(Int32.Parse(topicId));
+      var topic                   = _topicRepository.Load(Int32.Parse(topicId, CultureInfo.InvariantCulture));
 
     /*----------------------------------------------------------------------------------------------------------------------------
     | Write out JSON for existing topic, if available
     \---------------------------------------------------------------------------------------------------------------------------*/
-      if (topic != null) {
+      if (topic is not null) {
         topicJson               += $"{{"
           + $"'id'              : '{topic.Id}', "
           + $"'key'             : '{EncodeJsonValue(topic.Key)}', "
diff --git a/OnTopic.Editor.AspNetCore/Components/TopicListViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/TopicListViewComponent.cs
index ccf85d8c..acfabd87 100644
--- a/OnTopic.Editor.AspNetCore/Components/TopicListViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/TopicListViewComponent.cs
@@ -5,6 +5,7 @@
 \=============================================================================================================================*/
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Linq;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Rendering;
@@ -12,6 +13,7 @@
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Metadata;
 using OnTopic.Editor.Models.Queryable;
+using OnTopic.Internal.Diagnostics;
 using OnTopic.Querying;
 using OnTopic.Repositories;
 
@@ -52,6 +54,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix = null
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set configuration values
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -76,7 +84,7 @@ public IViewComponentResult Invoke(
       | Set label
       \-----------------------------------------------------------------------------------------------------------------------*/
       viewModel.TopicList.Add(
-        new SelectListItem {
+        new() {
           Value = "",
           Text = attribute.DefaultLabel
         }
@@ -92,7 +100,7 @@ public IViewComponentResult Invoke(
       \-----------------------------------------------------------------------------------------------------------------------*/
       var rootTopic             = (Topic)null;
 
-      if (attribute.RelativeTopicBase != null) {
+      if (attribute.RelativeTopicBase is not null) {
         var baseTopic             = _topicRepository.Load(currentTopic.UniqueKey);
         if (String.IsNullOrEmpty(currentTopic.Key)) {
           baseTopic               = TopicFactory.Create("NewTopic", currentTopic.ContentType, baseTopic);
@@ -110,7 +118,7 @@ public IViewComponentResult Invoke(
         rootTopic = _topicRepository.Load(attribute.RootTopic?.UniqueKey?? attribute.RootTopicKey);
       }
 
-      if (rootTopic != null && !String.IsNullOrEmpty(attribute.RelativeTopicPath)) {
+      if (rootTopic is not null && !String.IsNullOrEmpty(attribute.RelativeTopicPath)) {
         rootTopic = rootTopic.GetByUniqueKey(rootTopic.GetUniqueKey() + ":" + attribute.RelativeTopicPath);
       }
 
@@ -133,7 +141,7 @@ public IViewComponentResult Invoke(
         var value = getValue(topic);
 
         viewModel.TopicList.Add(
-          new SelectListItem {
+          new() {
             Value = value,
             Text = title,
             Selected = value == defaultValue
@@ -169,8 +177,8 @@ public static List<QueryResultTopicViewModel> GetTopics(
       /*------------------------------------------------------------------------------------------------------------------------
       | Swallow missing topic
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (topic == null) {
-        return new List<QueryResultTopicViewModel>();
+      if (topic is null) {
+        return new();
       }
 
       /*------------------------------------------------------------------------------------------------------------------------
@@ -219,9 +227,9 @@ public static List<QueryResultTopicViewModel> GetTopics(
     | Replaces tokenized parameters (e.g., {Key}) in the source string based on the source Topic's properties.
     \-------------------------------------------------------------------------------------------------------------------------*/
     private static string ReplaceTokens(QueryResultTopicViewModel topic, string source) {
-      if (topic != null && !String.IsNullOrEmpty(source)) {
+      if (topic is not null && !String.IsNullOrEmpty(source)) {
         source = source
-          .Replace("{TopicId}", topic.Id.ToString(), StringComparison.InvariantCultureIgnoreCase)
+          .Replace("{TopicId}", topic.Id.ToString(CultureInfo.InvariantCulture), StringComparison.InvariantCultureIgnoreCase)
           .Replace("{Key}", topic.Key, StringComparison.InvariantCultureIgnoreCase)
           .Replace("{UniqueKey}", topic.UniqueKey, StringComparison.InvariantCultureIgnoreCase)
           .Replace("{WebPath}", topic.WebPath, StringComparison.InvariantCultureIgnoreCase)
diff --git a/OnTopic.Editor.AspNetCore/Components/TopicReferenceViewComponent.cs b/OnTopic.Editor.AspNetCore/Components/TopicReferenceViewComponent.cs
index 443e2a6f..e8f60b70 100644
--- a/OnTopic.Editor.AspNetCore/Components/TopicReferenceViewComponent.cs
+++ b/OnTopic.Editor.AspNetCore/Components/TopicReferenceViewComponent.cs
@@ -7,6 +7,7 @@
 using Microsoft.AspNetCore.Mvc;
 using OnTopic.Editor.Models;
 using OnTopic.Editor.Models.Metadata;
+using OnTopic.Internal.Diagnostics;
 
 namespace OnTopic.Editor.AspNetCore.Components {
 
@@ -39,6 +40,12 @@ public IViewComponentResult Invoke(
       string htmlFieldPrefix
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(currentTopic, nameof(currentTopic));
+      Contract.Requires(attribute, nameof(attribute));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Set HTML prefix
       \-----------------------------------------------------------------------------------------------------------------------*/
diff --git a/OnTopic.Editor.AspNetCore/Controllers/EditorController.cs b/OnTopic.Editor.AspNetCore/Controllers/EditorController.cs
index 8578d51a..d6d2686d 100644
--- a/OnTopic.Editor.AspNetCore/Controllers/EditorController.cs
+++ b/OnTopic.Editor.AspNetCore/Controllers/EditorController.cs
@@ -4,6 +4,7 @@
 | Project       Topics Library
 \=============================================================================================================================*/
 using System;
+using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Text;
@@ -42,7 +43,7 @@ public class EditorController : Controller {
     \-------------------------------------------------------------------------------------------------------------------------*/
     private readonly            ITopicRepository                _topicRepository;
     private readonly            ITopicMappingService            _topicMappingService;
-    private                     Topic                           _currentTopic                   = null;
+    private                     Topic                           _currentTopic;
 
     /*==========================================================================================================================
     | CONSTRUCTOR
@@ -59,8 +60,8 @@ ITopicMappingService topicMappingService
       /*------------------------------------------------------------------------------------------------------------------------
       | Validate input
       \-----------------------------------------------------------------------------------------------------------------------*/
-      Contract.Requires(topicRepository != null, "A concrete implementation of an ITopicRepository is required.");
-      Contract.Requires(topicMappingService != null, "A concrete implementation of an ITopicMappingService is required.");
+      Contract.Requires(topicRepository, "A concrete implementation of an ITopicRepository is required.");
+      Contract.Requires(topicMappingService, "A concrete implementation of an ITopicMappingService is required.");
 
       /*------------------------------------------------------------------------------------------------------------------------
       | Set values locally
@@ -88,7 +89,7 @@ ITopicMappingService topicMappingService
     /// <returns>The Topic associated with the current request.</returns>
     protected Topic CurrentTopic {
       get {
-        if (_currentTopic == null) {
+        if (_currentTopic is null) {
           _currentTopic = TopicRepository.Load(RouteData);
         }
         return _currentTopic;
@@ -129,19 +130,24 @@ protected async Task<T> GetEditorViewModel<T>(
       bool isModal
     ) where T: EditorViewModel, new() {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(contentTypeDescriptor, nameof(contentTypeDescriptor));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | ESTABLISH CONTENT TYPE VIEW MODEL
       \-----------------------------------------------------------------------------------------------------------------------*/
-      var contentTypeViewModel  = await _topicMappingService.MapAsync<ContentTypeDescriptorTopicViewModel>(contentTypeDescriptor);
+      var contentTypeViewModel  = await _topicMappingService.MapAsync<ContentTypeDescriptorTopicViewModel>(contentTypeDescriptor).ConfigureAwait(true);
       var parentTopic           = isNew ? CurrentTopic : CurrentTopic.Parent;
 
       /*------------------------------------------------------------------------------------------------------------------------
       | CONSTRUCT VIEW MODEL
       \-----------------------------------------------------------------------------------------------------------------------*/
-      var topicViewModel        = await _topicMappingService.MapAsync<EditingTopicViewModel>(CurrentTopic);
+      var topicViewModel        = await _topicMappingService.MapAsync<EditingTopicViewModel>(CurrentTopic).ConfigureAwait(true);
 
       if (isNew) {
-        topicViewModel          = new EditingTopicViewModel() {
+        topicViewModel          = new() {
           ContentType           = contentTypeDescriptor.Key,
           UniqueKey             = CurrentTopic.GetUniqueKey(),
           Parent                = topicViewModel
@@ -155,7 +161,7 @@ bool isModal
       foreach (var attribute in contentTypeDescriptor.AttributeDescriptors) {
 
         //Serialize relationships, if it's a relationship type
-        if (!isNew && attribute.ModelType == ModelType.Relationship) {
+        if (!isNew && attribute.ModelType is ModelType.Relationship) {
           var relatedTopicIds = CurrentTopic.Relationships.GetTopics(attribute.Key).Select<Topic, int>(m => m.Id).ToArray();
           topicViewModel.Attributes.Add(attribute.Key, String.Join(",", relatedTopicIds));
         }
@@ -166,7 +172,7 @@ bool isModal
         }
 
         //For new topics that aren't derived from another topic, assign attribute default, if available
-        else if (CurrentTopic.DerivedTopic == null && !attribute.IsRequired && attribute.DefaultValue != null) {
+        else if (CurrentTopic.DerivedTopic is null && !attribute.IsRequired && attribute.DefaultValue is not null) {
           topicViewModel.Attributes.Add(attribute.Key, attribute.DefaultValue);
         }
 
@@ -214,7 +220,7 @@ public async Task<IActionResult> Edit(bool isNew = false, string contentType = n
       /*------------------------------------------------------------------------------------------------------------------------
       | ESTABLISH VIEW MODEL
       \-----------------------------------------------------------------------------------------------------------------------*/
-      var editorViewModel = await GetEditorViewModel<EditorViewModel>(contentTypeDescriptor, isNew, isModal);
+      var editorViewModel = await GetEditorViewModel<EditorViewModel>(contentTypeDescriptor, isNew, isModal).ConfigureAwait(true);
 
       /*------------------------------------------------------------------------------------------------------------------------
       | RETURN VIEW (MODEL)
@@ -241,20 +247,25 @@ public async Task<IActionResult> Edit(
       bool isModal = false
     ) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(model, nameof(model));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | SET VARIABLES
       \-----------------------------------------------------------------------------------------------------------------------*/
       var parentTopic           = isNew? CurrentTopic : CurrentTopic.Parent;
       var contentTypeDescriptor = GetContentType(contentType?? CurrentTopic.ContentType);
       var derivedTopicValue     = model.Attributes.Contains("TopicID")? model.Attributes["TopicID"].Value : "-1";
-      var derivedTopicId        = String.IsNullOrWhiteSpace(derivedTopicValue)? -1 : Int32.Parse(derivedTopicValue);
+      var derivedTopicId        = String.IsNullOrWhiteSpace(derivedTopicValue)? -1 : Int32.Parse(derivedTopicValue, CultureInfo.InvariantCulture);
       var derivedTopic          = (derivedTopicId >= 0)? TopicRepository.Load(derivedTopicId) : null;
       var newKey                = model.Attributes.Contains("Key")? model.Attributes["Key"].Value : null;
 
       /*------------------------------------------------------------------------------------------------------------------------
       | VALIDATE REQUIRED FIELDS
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (derivedTopic == null) {
+      if (derivedTopic is null) {
         foreach (var attribute in contentTypeDescriptor.AttributeDescriptors) {
           var submittedValue = model.Attributes.Contains(attribute.Key)? model.Attributes[attribute.Key] : null;
           if (attribute.IsRequired && !attribute.IsHidden && String.IsNullOrEmpty(submittedValue?.Value)) {
@@ -288,7 +299,7 @@ public async Task<IActionResult> Edit(
       if (!ModelState.IsValid) {
 
         //Establish view model
-        var editorViewModel = await GetEditorViewModel<EditorViewModel>(contentTypeDescriptor, isNew, isModal);
+        var editorViewModel = await GetEditorViewModel<EditorViewModel>(contentTypeDescriptor, isNew, isModal).ConfigureAwait(true);
 
         foreach (var attribute in contentTypeDescriptor.AttributeDescriptors) {
           var submittedValue = model.Attributes.Contains(attribute.Key)? model.Attributes[attribute.Key] : null;
@@ -311,7 +322,7 @@ public async Task<IActionResult> Edit(
         contentType = CurrentTopic.ContentType;
       }
 
-      if (derivedTopic != null && topic.DerivedTopic != derivedTopic) {
+      if (derivedTopic is not null && topic.DerivedTopic != derivedTopic) {
         topic.DerivedTopic = derivedTopic;
       }
 
@@ -340,10 +351,10 @@ public async Task<IActionResult> Edit(
         var attributeValue = model.Attributes[attribute.Key];
 
         //Save value
-        if (attribute.ModelType.Equals(ModelType.Relationship)) {
+        if (attribute.ModelType is ModelType.Relationship) {
           SetRelationships(topic, attribute, attributeValue);
         }
-        else if (attribute.Key.Equals("Key")) {
+        else if (attribute.Key is "Key") {
           topic.Key = attributeValue.Value.Replace(" ", "");
         }
         else {
@@ -366,7 +377,7 @@ public async Task<IActionResult> Edit(
       else if (isNew) {
         return RedirectToAction("Edit", new { path = topic.GetWebPath() });
       }
-      return await Edit();
+      return await Edit().ConfigureAwait(true);
 
     }
 
@@ -385,7 +396,7 @@ private void SetRelationships(Topic topic, AttributeDescriptor attribute, Attrib
         if (isTopicId && topicIdInt > 0) {
           relatedTopic = TopicRepository.Load(topicIdInt);
         }
-        if (relatedTopic != null) {
+        if (relatedTopic is not null) {
           topic.Relationships.SetTopic(attribute.Key, relatedTopic);
         }
       }
@@ -444,7 +455,7 @@ public IActionResult Delete(bool isModal = false) {
       /*--------------------------------------------------------------------------------------------------------------------------
       | If the content type is a nested list, display grandparent.
       \-------------------------------------------------------------------------------------------------------------------------*/
-      else if (parent.Attributes.GetValue("ContentType", "") == "List") {
+      else if (parent.Attributes.GetValue("ContentType", "") is "List") {
         return RedirectToAction(
           "Edit",
           new {
@@ -516,6 +527,11 @@ public IActionResult Move(int topicId, int targetTopicId = -1, int siblingId = -
     /// </summary>
     public JsonResult Json(TopicQueryOptions options) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(options, nameof(options));
+
       /*--------------------------------------------------------------------------------------------------------------------------
       | Get related topics
       \-------------------------------------------------------------------------------------------------------------------------*/
@@ -529,7 +545,7 @@ public JsonResult Json(TopicQueryOptions options) {
         }
 
         if (!String.IsNullOrWhiteSpace(options.RelatedNamespace)) {
-          relatedTopics = new ReadOnlyTopicCollection<Topic>(relatedTopic.Relationships.GetTopics(options.RelatedNamespace));
+          relatedTopics = new(relatedTopic.Relationships.GetTopics(options.RelatedNamespace));
         }
         else {
           relatedTopics = relatedTopic.Relationships.GetAllTopics();
@@ -546,7 +562,7 @@ public JsonResult Json(TopicQueryOptions options) {
       /*--------------------------------------------------------------------------------------------------------------------------
       | Return hierarchical view
       \-------------------------------------------------------------------------------------------------------------------------*/
-      return new JsonResult(jsonTopicViewModel);
+      return new(jsonTopicViewModel);
 
     }
 
@@ -566,7 +582,7 @@ public async Task<IActionResult> Export() {
       /*------------------------------------------------------------------------------------------------------------------------
       | ESTABLISH VIEW MODEL
       \-----------------------------------------------------------------------------------------------------------------------*/
-      var editorViewModel = await GetEditorViewModel<ExportViewModel>(contentTypeDescriptor, false, false);
+      var editorViewModel = await GetEditorViewModel<ExportViewModel>(contentTypeDescriptor, false, false).ConfigureAwait(true);
 
       /*------------------------------------------------------------------------------------------------------------------------
       | RETURN VIEW (MODEL)
@@ -617,7 +633,7 @@ public async Task<IActionResult> Import() {
       /*------------------------------------------------------------------------------------------------------------------------
       | ESTABLISH VIEW MODEL
       \-----------------------------------------------------------------------------------------------------------------------*/
-      var editorViewModel = await GetEditorViewModel<ImportViewModel>(contentTypeDescriptor, false, false);
+      var editorViewModel = await GetEditorViewModel<ImportViewModel>(contentTypeDescriptor, false, false).ConfigureAwait(true);
 
       /*------------------------------------------------------------------------------------------------------------------------
       | RETURN VIEW (MODEL)
@@ -636,6 +652,12 @@ public async Task<IActionResult> Import() {
     [HttpPost]
     public async Task<IActionResult> Import(IFormFile jsonFile, [Bind(Prefix = "ImportOptions")]ImportOptions options) {
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Validate parameters
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      Contract.Requires(jsonFile, nameof(jsonFile));
+      Contract.Requires(options, nameof(options));
+
       /*------------------------------------------------------------------------------------------------------------------------
       | ESTABLISH CONTENT TYPE VIEW MODEL
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -644,7 +666,7 @@ public async Task<IActionResult> Import(IFormFile jsonFile, [Bind(Prefix = "Impo
       /*------------------------------------------------------------------------------------------------------------------------
       | ESTABLISH VIEW MODEL
       \-----------------------------------------------------------------------------------------------------------------------*/
-      var editorViewModel       = await GetEditorViewModel<ImportViewModel>(contentTypeDescriptor, false, false);
+      var editorViewModel       = await GetEditorViewModel<ImportViewModel>(contentTypeDescriptor, false, false).ConfigureAwait(true);
 
       options.CurrentUser       = HttpContext.User.Identity.Name?? "System";
 
@@ -653,7 +675,7 @@ public async Task<IActionResult> Import(IFormFile jsonFile, [Bind(Prefix = "Impo
       /*------------------------------------------------------------------------------------------------------------------------
       | VALIDATE PARAMETERS
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (jsonFile == null) {
+      if (jsonFile is null) {
         ModelState.AddModelError("jsonFile", "The JSON file is required to import data.");
         return View(editorViewModel);
       }
@@ -664,7 +686,7 @@ public async Task<IActionResult> Import(IFormFile jsonFile, [Bind(Prefix = "Impo
       var json                  = new StringBuilder();
       using (var reader = new StreamReader(jsonFile.OpenReadStream())) {
         while (reader.Peek() >= 0) {
-          json.AppendLine(await reader.ReadLineAsync());
+          json.AppendLine(await reader.ReadLineAsync().ConfigureAwait(true));
         }
       }
       var jsonString            = json.ToString();
@@ -673,7 +695,7 @@ public async Task<IActionResult> Import(IFormFile jsonFile, [Bind(Prefix = "Impo
       };
       var topicData             = JsonSerializer.Deserialize<TopicData>(jsonString, jsonOptions);
 
-      if (topicData == null) {
+      if (topicData is null) {
         ModelState.AddModelError("jsonFile", "The JSON file could not be read correctly.");
         return View(editorViewModel);
       }
@@ -685,16 +707,16 @@ public async Task<IActionResult> Import(IFormFile jsonFile, [Bind(Prefix = "Impo
       var target                = TopicRepository.Load(uniqueKey);
 
       //Create target if it doesn't exist
-      if (target == null) {
+      if (target is null) {
         var parentKey           = uniqueKey.Substring(0, uniqueKey.LastIndexOf(":", StringComparison.InvariantCulture));
         var parent              = TopicRepository.Load(parentKey);
 
-        if (parent != null) {
+        if (parent is not null) {
           target                = TopicFactory.Create(topicData.Key, topicData.ContentType, parent);
         }
       }
 
-      if (target == null) {
+      if (target is null) {
         ModelState.AddModelError(
           "jsonFile",
           $"The root namespace, '{topicData.UniqueKey}', is not available in the topic graph"
diff --git a/OnTopic.Editor.AspNetCore/EditorServiceCollectionExtensions.cs b/OnTopic.Editor.AspNetCore/EditorServiceCollectionExtensions.cs
index 1447cb56..bf57dee3 100644
--- a/OnTopic.Editor.AspNetCore/EditorServiceCollectionExtensions.cs
+++ b/OnTopic.Editor.AspNetCore/EditorServiceCollectionExtensions.cs
@@ -32,7 +32,7 @@ public static IMvcBuilder AddTopicEditor(this IMvcBuilder services) {
       /*------------------------------------------------------------------------------------------------------------------------
       | Validate parameters
       \-----------------------------------------------------------------------------------------------------------------------*/
-      Contract.Requires<ArgumentNullException>(services != null, nameof(services));
+      Contract.Requires(services, nameof(services));
 
       /*------------------------------------------------------------------------------------------------------------------------
       | Register services
diff --git a/OnTopic.Editor.AspNetCore/Infrastructure/AttributeBindingModelBinder.cs b/OnTopic.Editor.AspNetCore/Infrastructure/AttributeBindingModelBinder.cs
index 54385e33..f63c611a 100644
--- a/OnTopic.Editor.AspNetCore/Infrastructure/AttributeBindingModelBinder.cs
+++ b/OnTopic.Editor.AspNetCore/Infrastructure/AttributeBindingModelBinder.cs
@@ -61,7 +61,7 @@ public Task BindModelAsync(ModelBindingContext bindingContext) {
       \-----------------------------------------------------------------------------------------------------------------------*/
       //The ASP.NET Core binder will keep iterating over the index until no result is returned. Assume failure to located
       //dependency fields means this point has been reached.
-      if (key == null || editorType == null) {
+      if (key is null || editorType is null) {
         return Task.CompletedTask;
       }
 
diff --git a/OnTopic.Editor.AspNetCore/Infrastructure/AttributeBindingModelBinderProvider.cs b/OnTopic.Editor.AspNetCore/Infrastructure/AttributeBindingModelBinderProvider.cs
index 80c00ef0..9613ca9f 100644
--- a/OnTopic.Editor.AspNetCore/Infrastructure/AttributeBindingModelBinderProvider.cs
+++ b/OnTopic.Editor.AspNetCore/Infrastructure/AttributeBindingModelBinderProvider.cs
@@ -35,7 +35,7 @@ public IModelBinder GetBinder(ModelBinderProviderContext context) {
       /*------------------------------------------------------------------------------------------------------------------------
       | VALIDATE INPUT
       \-----------------------------------------------------------------------------------------------------------------------*/
-      Contract.Requires<ArgumentNullException>(context != null, $"A {nameof(ModelBinderProviderContext)} reference is required.");
+      Contract.Requires(context, $"A {nameof(ModelBinderProviderContext)} reference is required.");
 
       /*------------------------------------------------------------------------------------------------------------------------
       | RETURN BINDER (IF APPROPRIATE)
diff --git a/OnTopic.Editor.AspNetCore/Infrastructure/TopicQueryService.cs b/OnTopic.Editor.AspNetCore/Infrastructure/TopicQueryService.cs
index 50c02975..a2feacf3 100644
--- a/OnTopic.Editor.AspNetCore/Infrastructure/TopicQueryService.cs
+++ b/OnTopic.Editor.AspNetCore/Infrastructure/TopicQueryService.cs
@@ -99,8 +99,8 @@ private void MapQueryResult(
           options.UseKeyAsText ? topic.Key : topic.Title,
           topic.GetUniqueKey(),
           topic.GetWebPath(),
-          options.EnableCheckboxes ? (options.MarkRelated ? related.Contains(topic) : true) : new bool?(),
-          topic.Attributes.GetValue("DisableDelete", "0").Equals("0"),
+          options.EnableCheckboxes ? (!options.MarkRelated || related.Contains(topic)) : new bool?(),
+          topic.Attributes.GetValue("DisableDelete", "0") is "0",
           options.ExpandRelated && related.Any(r => r.GetUniqueKey().StartsWith(topic.GetUniqueKey(), StringComparison.Ordinal))
         );
 
@@ -145,19 +145,20 @@ public static bool IsValidTopic(Topic topic, TopicQueryOptions options) {
       | Validate basic properties
       \-----------------------------------------------------------------------------------------------------------------------*/
       if (!options.ShowAll && !topic.IsVisible()) return false;
-      if (!options.ShowNestedTopics && topic.ContentType.Equals("List")) return false;
-      if (options.ResultLimit.Equals(0)) return false;
+      if (!options.ShowNestedTopics && topic.ContentType is "List") return false;
+      if (options.ResultLimit is 0) return false;
 
       /*------------------------------------------------------------------------------------------------------------------------
       | Validate filtered attribute
       \-----------------------------------------------------------------------------------------------------------------------*/
       if (!String.IsNullOrEmpty(options.AttributeName) && !String.IsNullOrEmpty(options.AttributeName)) {
+        var attributeValue = topic.Attributes.GetValue(options.AttributeName, "");
         if (options.UsePartialMatch) {
-          if (topic.Attributes.GetValue(options.AttributeName, "").IndexOf(options.AttributeValue) == -1) {
+          if (attributeValue.IndexOf(options.AttributeValue, StringComparison.Ordinal) is -1) {
             return false;
           }
         }
-        if (!topic.Attributes.GetValue(options.AttributeName, "").Equals(options.AttributeValue)) {
+        if (!attributeValue.Equals(options.AttributeValue)) {
           return false;
         }
       }
diff --git a/OnTopic.Editor.AspNetCore/Models/ContentTypeListViewModel.cs b/OnTopic.Editor.AspNetCore/Models/ContentTypeListViewModel.cs
index 378770b4..6724958e 100644
--- a/OnTopic.Editor.AspNetCore/Models/ContentTypeListViewModel.cs
+++ b/OnTopic.Editor.AspNetCore/Models/ContentTypeListViewModel.cs
@@ -47,7 +47,7 @@ public ContentTypeListViewModel() { }
     ///   cref="TopicListAttributeViewModel"/> representing countries, <c>US</c> might by the key associated with a <c>United
     ///   States</c> value.
     /// </remarks>
-    public List<SelectListItem> TopicList { get; } = new List<SelectListItem>();
+    public List<SelectListItem> TopicList { get; } = new();
 
     /*==========================================================================================================================
     | ATTRIBUTE KEY
diff --git a/OnTopic.Editor.AspNetCore/Models/FileListAttributeViewModel.cs b/OnTopic.Editor.AspNetCore/Models/FileListAttributeViewModel.cs
index 5863cf88..0bbba1e8 100644
--- a/OnTopic.Editor.AspNetCore/Models/FileListAttributeViewModel.cs
+++ b/OnTopic.Editor.AspNetCore/Models/FileListAttributeViewModel.cs
@@ -48,7 +48,7 @@ public FileListAttributeViewModel(
     ///   The <see cref="SelectListItem.Value"/>represents the path that will be saved to the database; the <see
     ///   cref="SelectListItem.Text"/> represents simply the file name itself.
     /// </remarks>
-    public List<SelectListItem> Files { get; set; } = new List<SelectListItem>();
+    public List<SelectListItem> Files { get; } = new();
 
     /*==========================================================================================================================
     | ABSOLUTE PATH
diff --git a/OnTopic.Editor.AspNetCore/Models/TopicListAttributeViewModel.cs b/OnTopic.Editor.AspNetCore/Models/TopicListAttributeViewModel.cs
index 7fd9183e..471fbc64 100644
--- a/OnTopic.Editor.AspNetCore/Models/TopicListAttributeViewModel.cs
+++ b/OnTopic.Editor.AspNetCore/Models/TopicListAttributeViewModel.cs
@@ -48,7 +48,7 @@ public TopicListAttributeViewModel(
     ///   cref="TopicListAttributeViewModel"/> representing countries, <c>US</c> might by the key associated with a <c>United
     ///   States</c> value.
     /// </remarks>
-    public List<SelectListItem> TopicList { get; } = new List<SelectListItem>();
+    public List<SelectListItem> TopicList { get; } = new();
 
   } // Class
 } // Namespace
\ No newline at end of file
diff --git a/OnTopic.Editor.AspNetCore/OnTopic.Editor.AspNetCore.csproj b/OnTopic.Editor.AspNetCore/OnTopic.Editor.AspNetCore.csproj
index 0f3327cf..0922069b 100644
--- a/OnTopic.Editor.AspNetCore/OnTopic.Editor.AspNetCore.csproj
+++ b/OnTopic.Editor.AspNetCore/OnTopic.Editor.AspNetCore.csproj
@@ -2,6 +2,7 @@
 
   <PropertyGroup>
     <TargetFramework>netcoreapp3.1</TargetFramework>
+    <LangVersion>9.0</LangVersion>
     <AddRazorSupportForMvc>true</AddRazorSupportForMvc>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
   </PropertyGroup>
@@ -26,14 +27,18 @@
 
   <ItemGroup>
     <FrameworkReference Include="Microsoft.AspNetCore.App" />
-    <PackageReference Include="GitVersionTask" Version="5.3.7">
+    <PackageReference Include="GitVersionTask" Version="5.5.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="OnTopic" Version="4.5.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="3.3.1">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+    <PackageReference Include="OnTopic" Version="4.6.0" />
     <PackageReference Include="OnTopic.Data.Transfer" Version="1.2.0" />
-    <PackageReference Include="OnTopic.ViewModels" Version="4.5.0" />
-    <PackageReference Include="OnTopic.AspNetCore.Mvc" Version="4.5.0" />
+    <PackageReference Include="OnTopic.ViewModels" Version="4.6.0" />
+    <PackageReference Include="OnTopic.AspNetCore.Mvc" Version="4.6.0" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/OnTopic.Editor.AspNetCore/Shared/Styles/Layout/_layout.scss b/OnTopic.Editor.AspNetCore/Shared/Styles/Layout/_layout.scss
index 35ab3170..3c4cf723 100644
--- a/OnTopic.Editor.AspNetCore/Shared/Styles/Layout/_layout.scss
+++ b/OnTopic.Editor.AspNetCore/Shared/Styles/Layout/_layout.scss
@@ -78,6 +78,7 @@ body {
 //----------------------------------------------------------------------------------------------
 .dropdown-menu {
   padding                       : 10px;
+  min-width                     : 180px;
   li a {
     line-height                 : 1.4rem;
   }
diff --git a/OnTopic.Editor.AspNetCore/StandardEditorComposer.cs b/OnTopic.Editor.AspNetCore/StandardEditorComposer.cs
index c36ae678..c7409de5 100644
--- a/OnTopic.Editor.AspNetCore/StandardEditorComposer.cs
+++ b/OnTopic.Editor.AspNetCore/StandardEditorComposer.cs
@@ -66,9 +66,10 @@ public StandardEditorComposer(ITopicRepository topicRepository, IWebHostEnvironm
     /// <summary>
     ///   Determines whether a given type is capable of being activated by the <see cref="Activate"/> method.
     /// </summary>
-    public static bool IsEditorComponent(Type type) =>
-      typeof(StandardEditorComposer).Assembly.Equals(type.Assembly) &&
-      typeof(ViewComponent).IsAssignableFrom(type);
+    public static bool IsEditorComponent(Type type) {
+      Contract.Requires(type, nameof(type));
+      return typeof(StandardEditorComposer).Assembly.Equals(type.Assembly) && typeof(ViewComponent).IsAssignableFrom(type);
+    }
 
     /*==========================================================================================================================
     | METHOD: ACTIVATE EDITOR COMPONENT
@@ -85,7 +86,7 @@ public ViewComponent ActivateEditorComponent(
       Type                      type,
       ITopicRepository          topicRepository
     ) =>
-      type.Name switch {
+      type?.Name switch {
         nameof(BooleanViewComponent)                            => new BooleanViewComponent(),
         nameof(DateTimeViewComponent)                           => new DateTimeViewComponent(),
         nameof(DisplayOptionsViewComponent)                     => new DisplayOptionsViewComponent(),
diff --git a/OnTopic.Editor.AspNetCore/package-lock.json b/OnTopic.Editor.AspNetCore/package-lock.json
index 8d73b7dd..4866c692 100644
--- a/OnTopic.Editor.AspNetCore/package-lock.json
+++ b/OnTopic.Editor.AspNetCore/package-lock.json
@@ -4,16 +4,34 @@
   "lockfileVersion": 1,
   "dependencies": {
     "@gulp-sourcemaps/identity-map": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/@gulp-sourcemaps/identity-map/-/identity-map-1.0.2.tgz",
-      "integrity": "sha512-ciiioYMLdo16ShmfHBXJBOFm3xPC4AuwO4xeRpFeHz7WK9PYsWCmigagG2XyzZpubK4a3qNKoUBDhbzHfa50LQ==",
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/@gulp-sourcemaps/identity-map/-/identity-map-2.0.1.tgz",
+      "integrity": "sha512-Tb+nSISZku+eQ4X1lAkevcQa+jknn/OVUgZ3XCxEKIsLsqYuPoJwJOPQeaOk75X3WPftb29GWY1eqE7GLsXb1Q==",
       "dev": true,
       "requires": {
-        "acorn": "^5.0.3",
-        "css": "^2.2.1",
-        "normalize-path": "^2.1.1",
+        "acorn": "^6.4.1",
+        "normalize-path": "^3.0.0",
+        "postcss": "^7.0.16",
         "source-map": "^0.6.0",
-        "through2": "^2.0.3"
+        "through2": "^3.0.1"
+      },
+      "dependencies": {
+        "normalize-path": {
+          "version": "3.0.0",
+          "resolved": "https://registry.npmjs.org/normalize-path/-/normalize-path-3.0.0.tgz",
+          "integrity": "sha512-6eZs5Ls3WtCisHWp9S2GUy8dqkpGi4BVSz3GaqiE6ezub0512ESztXUwUB6C6IKbQkY2Pnb/mD4WYojCRwcwLA==",
+          "dev": true
+        },
+        "through2": {
+          "version": "3.0.2",
+          "resolved": "https://registry.npmjs.org/through2/-/through2-3.0.2.tgz",
+          "integrity": "sha512-enaDQ4MUyP2W6ZyT6EsMzqBPZaM/avg8iuo+l2d3QCs0J+6RaqkHV/2/lOwDTueBHeJ/2LG9lrLW3d5rWPucuQ==",
+          "dev": true,
+          "requires": {
+            "inherits": "^2.0.4",
+            "readable-stream": "2 || 3"
+          }
+        }
       }
     },
     "@gulp-sourcemaps/map-sources": {
@@ -39,9 +57,9 @@
       "dev": true
     },
     "acorn": {
-      "version": "5.7.4",
-      "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.7.4.tgz",
-      "integrity": "sha512-1D++VG7BhrtvQpNbBzovKNc1FLGGEE/oGe7b9xJm/RFHMBeUaUGpluV9RLjZa47YFdPcDAenEYuq9pQPcMdLJg==",
+      "version": "6.4.2",
+      "resolved": "https://registry.npmjs.org/acorn/-/acorn-6.4.2.tgz",
+      "integrity": "sha512-XtGIhXwF8YM8bJhGxG5kXgjkEuNGLTkoYqVE+KMR+aspr4KGYmKYg7yUe3KghyQ9yheNwLnjmzh/7+gfDBmHCQ==",
       "dev": true
     },
     "ajv": {
@@ -486,9 +504,9 @@
       "dev": true
     },
     "bootstrap": {
-      "version": "4.5.2",
-      "resolved": "https://registry.npmjs.org/bootstrap/-/bootstrap-4.5.2.tgz",
-      "integrity": "sha512-vlGn0bcySYl/iV+BGA544JkkZP5LB3jsmkeKLFQakCOwCM3AOk7VkldBz4jrzSe+Z0Ezn99NVXa1o45cQY4R6A==",
+      "version": "4.5.3",
+      "resolved": "https://registry.npmjs.org/bootstrap/-/bootstrap-4.5.3.tgz",
+      "integrity": "sha512-o9ppKQioXGqhw8Z7mah6KdTYpNQY//tipnkxppWhPbiSWdD+1raYsnhwEZjkTHYbGee4cVQ0Rx65EhOY/HNLcQ==",
       "dev": true
     },
     "brace-expansion": {
@@ -962,15 +980,26 @@
       }
     },
     "css": {
-      "version": "2.2.4",
-      "resolved": "https://registry.npmjs.org/css/-/css-2.2.4.tgz",
-      "integrity": "sha512-oUnjmWpy0niI3x/mPL8dVEI1l7MnG3+HHyRPHf+YFSbK+svOhXpmSOcDURUh2aOCgl2grzrOPt1nHLuCVFULLw==",
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/css/-/css-3.0.0.tgz",
+      "integrity": "sha512-DG9pFfwOrzc+hawpmqX/dHYHJG+Bsdb0klhyi1sDneOgGOXy9wQIC8hzyVp1e4NRYDBdxcylvywPkkXCHAzTyQ==",
       "dev": true,
       "requires": {
-        "inherits": "^2.0.3",
+        "inherits": "^2.0.4",
         "source-map": "^0.6.1",
-        "source-map-resolve": "^0.5.2",
-        "urix": "^0.1.0"
+        "source-map-resolve": "^0.6.0"
+      },
+      "dependencies": {
+        "source-map-resolve": {
+          "version": "0.6.0",
+          "resolved": "https://registry.npmjs.org/source-map-resolve/-/source-map-resolve-0.6.0.tgz",
+          "integrity": "sha512-KXBr9d/fO/bWo97NXsPIAW1bFSBOuCnjbNTBMO7N59hsv5i9yzRDfcYwwt0l04+VqnKC+EwzvJZIP/qkuMgR/w==",
+          "dev": true,
+          "requires": {
+            "atob": "^2.1.2",
+            "decode-uri-component": "^0.2.0"
+          }
+        }
       }
     },
     "css-color-names": {
@@ -1194,9 +1223,9 @@
       },
       "dependencies": {
         "debug": {
-          "version": "3.2.6",
-          "resolved": "https://registry.npmjs.org/debug/-/debug-3.2.6.tgz",
-          "integrity": "sha512-mel+jf7nrtEl5Pn1Qx46zARXKDpBbvzezse7p7LqINmdoIk8PYP5SySaxEmYv6TZ0JyEKA1hsCId6DIhgITtWQ==",
+          "version": "3.2.7",
+          "resolved": "https://registry.npmjs.org/debug/-/debug-3.2.7.tgz",
+          "integrity": "sha512-CFjzYYAi4ThfiQvizrFQevTTXHtnCqWfe7x1AhgEscTz6ZbLbfoLRLPugTQyBth6f8ZERVUSyWHFD/7Wu4t1XQ==",
           "dev": true,
           "requires": {
             "ms": "^2.1.1"
@@ -2153,15 +2182,14 @@
       }
     },
     "gulp-postcss": {
-      "version": "8.0.0",
-      "resolved": "https://registry.npmjs.org/gulp-postcss/-/gulp-postcss-8.0.0.tgz",
-      "integrity": "sha512-Wtl6vH7a+8IS/fU5W9IbOpcaLqKxd5L1DUOzaPmlnCbX1CrG0aWdwVnC3Spn8th0m8D59YbysV5zPUe1n/GJYg==",
+      "version": "9.0.0",
+      "resolved": "https://registry.npmjs.org/gulp-postcss/-/gulp-postcss-9.0.0.tgz",
+      "integrity": "sha512-5mSQ9CK8salSagrXgrVyILfEMy6I5rUGPRiR9rVjgJV9m/rwdZYUhekMr+XxDlApfc5ZdEJ8gXNZrU/TsgT5dQ==",
       "dev": true,
       "requires": {
-        "fancy-log": "^1.3.2",
+        "fancy-log": "^1.3.3",
         "plugin-error": "^1.0.1",
-        "postcss": "^7.0.2",
-        "postcss-load-config": "^2.0.0",
+        "postcss-load-config": "^2.1.1",
         "vinyl-sourcemaps-apply": "^0.2.1"
       },
       "dependencies": {
@@ -2225,22 +2253,22 @@
       }
     },
     "gulp-sourcemaps": {
-      "version": "2.6.5",
-      "resolved": "https://registry.npmjs.org/gulp-sourcemaps/-/gulp-sourcemaps-2.6.5.tgz",
-      "integrity": "sha512-SYLBRzPTew8T5Suh2U8jCSDKY+4NARua4aqjj8HOysBh2tSgT9u4jc1FYirAdPx1akUxxDeK++fqw6Jg0LkQRg==",
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/gulp-sourcemaps/-/gulp-sourcemaps-3.0.0.tgz",
+      "integrity": "sha512-RqvUckJkuYqy4VaIH60RMal4ZtG0IbQ6PXMNkNsshEGJ9cldUPRb/YCgboYae+CLAs1HQNb4ADTKCx65HInquQ==",
       "dev": true,
       "requires": {
-        "@gulp-sourcemaps/identity-map": "1.X",
-        "@gulp-sourcemaps/map-sources": "1.X",
-        "acorn": "5.X",
-        "convert-source-map": "1.X",
-        "css": "2.X",
-        "debug-fabulous": "1.X",
-        "detect-newline": "2.X",
-        "graceful-fs": "4.X",
-        "source-map": "~0.6.0",
-        "strip-bom-string": "1.X",
-        "through2": "2.X"
+        "@gulp-sourcemaps/identity-map": "^2.0.1",
+        "@gulp-sourcemaps/map-sources": "^1.0.0",
+        "acorn": "^6.4.1",
+        "convert-source-map": "^1.0.0",
+        "css": "^3.0.0",
+        "debug-fabulous": "^1.0.0",
+        "detect-newline": "^2.0.0",
+        "graceful-fs": "^4.0.0",
+        "source-map": "^0.6.0",
+        "strip-bom-string": "^1.0.0",
+        "through2": "^2.0.0"
       }
     },
     "gulp-uglify": {
@@ -2757,9 +2785,9 @@
       }
     },
     "is-promise": {
-      "version": "2.1.0",
-      "resolved": "https://registry.npmjs.org/is-promise/-/is-promise-2.1.0.tgz",
-      "integrity": "sha1-eaKp7OfwlugPNtKy87wWwf9L8/o=",
+      "version": "2.2.2",
+      "resolved": "https://registry.npmjs.org/is-promise/-/is-promise-2.2.2.tgz",
+      "integrity": "sha512-+lP4/6lKUBfQjZ2pdxThZvLUAafmZb8OAxFb8XXtiQmS35INgr85hdOGoEs124ez1FCnZJt6jau/T+alh58QFQ==",
       "dev": true
     },
     "is-regex": {
@@ -4078,9 +4106,9 @@
       }
     },
     "postcss-load-config": {
-      "version": "2.1.0",
-      "resolved": "https://registry.npmjs.org/postcss-load-config/-/postcss-load-config-2.1.0.tgz",
-      "integrity": "sha512-4pV3JJVPLd5+RueiVVB+gFOAa7GWc25XQcMp86Zexzke69mKf6Nx9LRcQywdz7yZI9n1udOxmLuAwTBypypF8Q==",
+      "version": "2.1.2",
+      "resolved": "https://registry.npmjs.org/postcss-load-config/-/postcss-load-config-2.1.2.tgz",
+      "integrity": "sha512-/rDeGV6vMUo3mwJZmeHfEDvwnTKKqQ0S7OHUi/kJvvtx3aWtyWG2/0ZWnzCt2keEclwN6Tf0DST2v9kITdOKYw==",
       "dev": true,
       "requires": {
         "cosmiconfig": "^5.0.0",
diff --git a/OnTopic.Editor.AspNetCore/package.json b/OnTopic.Editor.AspNetCore/package.json
index 2f03beea..3f7456ec 100644
--- a/OnTopic.Editor.AspNetCore/package.json
+++ b/OnTopic.Editor.AspNetCore/package.json
@@ -7,15 +7,15 @@
   },
   "license": "MIT",
   "devDependencies": {
-    "bootstrap": "^4.5.2",
+    "bootstrap": "^4.5.3",
     "cssnano": "^4.1.10",
     "gulp": "^4.0.2",
     "gulp-concat": "^2.6.1",
     "gulp-if": "^3.0.0",
     "gulp-jshint": "^2.1.0",
-    "gulp-postcss": "^8.0.0",
+    "gulp-postcss": "^9.0.0",
     "gulp-sass": "^4.1.0",
-    "gulp-sourcemaps": "^2.6.5",
+    "gulp-sourcemaps": "^3.0.0",
     "gulp-uglify": "^3.0.2",
     "jquery": "^3.5.1",
     "jquery-tokeninput": "^1.6.0",
diff --git a/OnTopic.Editor.Models/Collections/EditorAttributeCollection.cs b/OnTopic.Editor.Models/Collections/EditorAttributeCollection.cs
index 6ea81093..a0f049da 100644
--- a/OnTopic.Editor.Models/Collections/EditorAttributeCollection.cs
+++ b/OnTopic.Editor.Models/Collections/EditorAttributeCollection.cs
@@ -5,8 +5,8 @@
 \=============================================================================================================================*/
 using System;
 using System.Collections.ObjectModel;
-using System.Diagnostics.Contracts;
 using OnTopic.Editor.Models.Components.BindingModels;
+using OnTopic.Internal.Diagnostics;
 
 namespace OnTopic.Editor.Models.Collections {
 
@@ -36,7 +36,7 @@ public EditorAttributeCollection() : base(StringComparer.InvariantCultureIgnoreC
     /// <param name="item">The <see cref="Topic"/> object from which to extract the key.</param>
     /// <returns>The key for the specified collection item.</returns>
     protected override string GetKeyForItem(AttributeBindingModel item) {
-      Contract.Assume(item != null, "Assumes the item is available when deriving its key.");
+      Contract.Assume(item, "Assumes the item is available when deriving its key.");
       return item.Key;
     }
 
diff --git a/OnTopic.Editor.Models/Components/BindingModels/BooleanAttributeBindingModel.cs b/OnTopic.Editor.Models/Components/BindingModels/BooleanAttributeBindingModel.cs
index cb37e3dd..6f822ade 100644
--- a/OnTopic.Editor.Models/Components/BindingModels/BooleanAttributeBindingModel.cs
+++ b/OnTopic.Editor.Models/Components/BindingModels/BooleanAttributeBindingModel.cs
@@ -38,7 +38,7 @@ public BooleanAttributeBindingModel() : base() {
     /// <remarks>
     ///   Determines whether the value is checked and, if it is, returns "1"; otherwise returns "0".
     /// </remarks>
-    public override string GetValue() => Value.Equals("True")? "1" : "0";
+    public override string GetValue() => Value is "True"? "1" : "0";
 
   } // Class
 } // Namespace
\ No newline at end of file
diff --git a/OnTopic.Editor.Models/Components/ViewModels/DateTimeAttributeViewModel.cs b/OnTopic.Editor.Models/Components/ViewModels/DateTimeAttributeViewModel.cs
index f6a6f73e..a559dba4 100644
--- a/OnTopic.Editor.Models/Components/ViewModels/DateTimeAttributeViewModel.cs
+++ b/OnTopic.Editor.Models/Components/ViewModels/DateTimeAttributeViewModel.cs
@@ -4,6 +4,7 @@
 | Project       Topics Library
 \=============================================================================================================================*/
 using System;
+using System.Globalization;
 using OnTopic.Editor.Models.Metadata;
 
 namespace OnTopic.Editor.Models.Components.ViewModels {
@@ -21,8 +22,9 @@ public class DateTimeAttributeViewModel: AttributeViewModel<DateTimeAttributeTop
     /*==========================================================================================================================
     | PRIVATE VARIABLES
     \-------------------------------------------------------------------------------------------------------------------------*/
-    private                     string                          _defaultDate                    = null;
-    private                     string                          _defaultTime                    = null;
+    private                     string                          _defaultDate;
+    private                     string                          _defaultTime;
+    private readonly            IFormatProvider                 _format                         = CultureInfo.InvariantCulture;
 
     /*==========================================================================================================================
     | CONSTRUCTOR
@@ -54,11 +56,11 @@ public string GetDefaultDate() {
         var dateFormat = AttributeDescriptor.DateFormat.Replace("y", "yy").Replace("mm", "MM");
         if (!String.IsNullOrEmpty(Value)) {
           if (DateTime.TryParse(Value, out var dateValue)) {
-            _defaultDate        = dateValue.ToString(dateFormat);
+            _defaultDate        = dateValue.ToString(dateFormat, _format);
           }
         }
         else {
-          _defaultDate          = CalculateOffset(DateTime.Now).ToString(dateFormat);
+          _defaultDate          = CalculateOffset(DateTime.Now).ToString(dateFormat, _format);
         }
       }
       return _defaultDate;
@@ -74,11 +76,11 @@ public string GetDefaultTime() {
       if (String.IsNullOrEmpty(_defaultTime)) {
         if (!String.IsNullOrEmpty(Value)) {
           if (DateTime.TryParse(Value, out var timeValue)) {
-            _defaultTime        = timeValue.ToString(AttributeDescriptor.TimeFormat);
+            _defaultTime        = timeValue.ToString(AttributeDescriptor.TimeFormat, _format);
           }
         }
         else {
-          _defaultTime          = CalculateOffset(DateTime.Now).ToString(AttributeDescriptor.TimeFormat);
+          _defaultTime          = CalculateOffset(DateTime.Now).ToString(AttributeDescriptor.TimeFormat, _format);
         }
       }
       return _defaultTime;
@@ -92,7 +94,7 @@ public string GetDefaultTime() {
     /// </summary>
     public DateTime CalculateOffset(DateTime originalDate) {
       var offset = AttributeDescriptor.DateTimeOffset?? 0;
-      if (AttributeDescriptor.DateTimeOffset == 0) return originalDate;
+      if (AttributeDescriptor.DateTimeOffset is 0) return originalDate;
       return AttributeDescriptor.DateTimeOffsetUnits switch {
         "Minutes"               => originalDate.AddMinutes(offset),
         "Hours"                 => originalDate.AddHours(offset),
diff --git a/OnTopic.Editor.Models/Components/ViewModels/IncomingRelationshipAttributeViewModel.cs b/OnTopic.Editor.Models/Components/ViewModels/IncomingRelationshipAttributeViewModel.cs
index a722a492..2d7592b8 100644
--- a/OnTopic.Editor.Models/Components/ViewModels/IncomingRelationshipAttributeViewModel.cs
+++ b/OnTopic.Editor.Models/Components/ViewModels/IncomingRelationshipAttributeViewModel.cs
@@ -45,7 +45,7 @@ public IncomingRelationshipAttributeViewModel(
     ///   Provides a list of <see cref="Topic"/>s which are related to the current <see cref="Topic"/> based on the specified
     ///   <see cref="NamedTopicCollection.Name"/>.
     /// </summary>
-    public List<TopicViewModel> RelatedTopics { get; set; } = new List<TopicViewModel>();
+    public List<TopicViewModel> RelatedTopics { get; } = new();
 
   } // Class
 } // Namespace
\ No newline at end of file
diff --git a/OnTopic.Editor.Models/EditingTopicViewModel.cs b/OnTopic.Editor.Models/EditingTopicViewModel.cs
index 7ddd96b6..e32235fc 100644
--- a/OnTopic.Editor.Models/EditingTopicViewModel.cs
+++ b/OnTopic.Editor.Models/EditingTopicViewModel.cs
@@ -35,7 +35,9 @@ public EditingTopicViewModel() : base() {}
     ///   Provides a collection of <see cref="DateTime"/> instances during which the represented <see cref="Topic"/> was
     ///   modified.
     /// </summary>
-    public List<DateTime> VersionHistory { get; set; } = new List<DateTime>();
+    #pragma warning disable CA2227 // Collection properties should be read only
+    public List<DateTime> VersionHistory { get; set; } = new();
+    #pragma warning restore CA2227 // Collection properties should be read only
 
     /*==========================================================================================================================
     | PROPERTY: DERIVED TOPIC
@@ -52,7 +54,7 @@ public EditingTopicViewModel() : base() {}
     /// <summary>
     ///   A collection of attribute values, as assigned directly to the topic. Does not include inherited or derived values.
     /// </summary>
-    public Dictionary<string, string> Attributes { get; set; } = new Dictionary<string, string>();
+    public Dictionary<string, string> Attributes { get; } = new();
 
     /*==========================================================================================================================
     | PROPERTY: INHERITED ATTRIBUTES
@@ -60,7 +62,7 @@ public EditingTopicViewModel() : base() {}
     /// <summary>
     ///   A collection of inherited attribute values, as inferred from derived or upstream topics.
     /// </summary>
-    public Dictionary<string, string> InheritedAttributes { get; set; } = new Dictionary<string, string>();
+    public Dictionary<string, string> InheritedAttributes { get; } = new();
 
   } // Class
 } // Namespace
\ No newline at end of file
diff --git a/OnTopic.Editor.Models/EditorBindingModel.cs b/OnTopic.Editor.Models/EditorBindingModel.cs
index 64408e54..fef85ae8 100644
--- a/OnTopic.Editor.Models/EditorBindingModel.cs
+++ b/OnTopic.Editor.Models/EditorBindingModel.cs
@@ -16,26 +16,13 @@ namespace OnTopic.Editor.Models {
   /// </summary>
   public class EditorBindingModel {
 
-    /*==========================================================================================================================
-    | CONSTRUCTOR
-    \-------------------------------------------------------------------------------------------------------------------------*/
-    /// <summary>
-    ///   Initializes a new instance of the <see cref="AttributeValue"/> class, using the specified key/value pair.
-    /// </summary>
-    public EditorBindingModel() {
-      Attributes = new EditorAttributeCollection();
-    }
-
     /*==========================================================================================================================
     | ATTRIBUTES
     \-------------------------------------------------------------------------------------------------------------------------*/
     /// <summary>
     ///   Collection of attribute values extracted from the post.
     /// </summary>
-    public EditorAttributeCollection Attributes {
-      get;
-      set;
-    }
+    public EditorAttributeCollection Attributes { get; } = new();
 
   } // Class
 } // Namespace
\ No newline at end of file
diff --git a/OnTopic.Editor.Models/EditorViewModel.cs b/OnTopic.Editor.Models/EditorViewModel.cs
index 01e34614..7adcbfc0 100644
--- a/OnTopic.Editor.Models/EditorViewModel.cs
+++ b/OnTopic.Editor.Models/EditorViewModel.cs
@@ -39,7 +39,7 @@ public class EditorViewModel {
     /// <summary>
     ///   Determines whether or not the page should be rendered as a modal (e.g., including the chrome or not).
     /// </summary>
-    public bool IsModal { get; set; } = false;
+    public bool IsModal { get; set; }
 
     /*==========================================================================================================================
     | IS NEW?
@@ -47,7 +47,7 @@ public class EditorViewModel {
     /// <summary>
     ///   Determines whether or not the page is being newly created.
     /// </summary>
-    public bool IsNew { get; set; } = false;
+    public bool IsNew { get; set; }
 
   } // Class
 } // Namespace
\ No newline at end of file
diff --git a/OnTopic.Editor.Models/Metadata/AttributeDescriptorTopicViewModel.cs b/OnTopic.Editor.Models/Metadata/AttributeDescriptorTopicViewModel.cs
index a579cbc5..8d76d706 100644
--- a/OnTopic.Editor.Models/Metadata/AttributeDescriptorTopicViewModel.cs
+++ b/OnTopic.Editor.Models/Metadata/AttributeDescriptorTopicViewModel.cs
@@ -5,6 +5,7 @@
 \=============================================================================================================================*/
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Linq;
 using OnTopic.Metadata;
 using OnTopic.Metadata.AttributeTypes;
@@ -22,17 +23,7 @@ public class AttributeDescriptorTopicViewModel: ViewModels.TopicViewModel {
     /*==========================================================================================================================
     | PRIVATE VARIABLES
     \-------------------------------------------------------------------------------------------------------------------------*/
-    private                     Dictionary<string, string>      _configuration;
-
-    /*==========================================================================================================================
-    | CONSTRUCTOR
-    \-------------------------------------------------------------------------------------------------------------------------*/
-    /// <summary>
-    ///   Initializes a new instance of the <see cref="AttributeDescriptorTopicViewModel"/> class.
-    /// </summary>
-    public AttributeDescriptorTopicViewModel() {
-      _configuration            = new Dictionary<string, string>();
-    }
+    private                     Dictionary<string, string>      _configuration                  = new();
 
     /*==========================================================================================================================
     | PROPERTY: DESCRIPTION
@@ -73,7 +64,6 @@ public AttributeDescriptorTopicViewModel() {
     public string DisplayGroup { get; set; }
 
     #region LegacyConfiguration
-    #pragma warning disable CS0618 // Type or member is obsolete
 
     /*==========================================================================================================================
     | PROPERTY: DEFAULT CONFIGURATION
@@ -102,13 +92,13 @@ public AttributeDescriptorTopicViewModel() {
     )]
     public IDictionary<string, string> Configuration {
       get {
-        if (_configuration.Count.Equals(0) && DefaultConfiguration?.Length > 0) {
+        if (_configuration.Count is 0 && DefaultConfiguration?.Length > 0) {
           _configuration = DefaultConfiguration
             .Split(' ')
             .Select(value => value.Split('='))
             .ToDictionary(
               pair => pair[0],
-              pair => pair.Count().Equals(2) ? pair[1]?.Replace("\"", "") : null
+              pair => pair.Length is 2? pair[1]?.Replace("\"", "") : null
             );
         }
         return _configuration;
@@ -128,7 +118,7 @@ public IDictionary<string, string> Configuration {
       "AttributeDescriptor."
     )]
     public string GetConfigurationValue(string key, string defaultValue = null) {
-      if (Configuration != null && Configuration.ContainsKey(key) && Configuration[key] != null) {
+      if (Configuration is not null && Configuration.ContainsKey(key) && Configuration[key] is not null) {
         return Configuration[key].ToString();
       }
       return defaultValue;
@@ -164,13 +154,12 @@ public bool GetBooleanConfigurationValue(string key, bool defaultValue = false)
       "AttributeDescriptor."
     )]
     public int GetIntegerConfigurationValue(string key, int defaultValue = 0) {
-      if (Int32.TryParse(GetConfigurationValue(key, defaultValue.ToString()), out var value)) {
+      if (Int32.TryParse(GetConfigurationValue(key, defaultValue.ToString(CultureInfo.InvariantCulture)), out var value)) {
         return value;
       }
       return defaultValue;
     }
 
-    #pragma warning restore CS0618 // Type or member is obsolete
     #endregion LegacyConfiguration
 
     /*==========================================================================================================================
diff --git a/OnTopic.Editor.Models/Metadata/ContentTypeDescriptorTopicViewModel.cs b/OnTopic.Editor.Models/Metadata/ContentTypeDescriptorTopicViewModel.cs
index 6fc9d751..624c9c4e 100644
--- a/OnTopic.Editor.Models/Metadata/ContentTypeDescriptorTopicViewModel.cs
+++ b/OnTopic.Editor.Models/Metadata/ContentTypeDescriptorTopicViewModel.cs
@@ -35,7 +35,7 @@ public ContentTypeDescriptorTopicViewModel(): base() {}
     ///   cref="AttributeDescriptor"/> permitted by the underlying <see cref="ContentTypeDescriptor"/>.
     /// </summary>
     [Follow(Relationships.Relationships|Relationships.References)]
-    public List<AttributeDescriptorTopicViewModel> AttributeDescriptors { get; } = new List<AttributeDescriptorTopicViewModel>();
+    public List<AttributeDescriptorTopicViewModel> AttributeDescriptors { get; } = new();
 
     /*==========================================================================================================================
     | PROPERTY: DESCRIPTION
@@ -69,7 +69,7 @@ public ContentTypeDescriptorTopicViewModel(): base() {}
     ///   Determines which <see cref="ContentType"/>s, if any, are permitted to be created under <see cref="Topic"/>s of the
     ///   current <see cref="ContentType"/>.
     /// </summary>
-    public List<ContentTypeDescriptorTopicViewModel> PermittedContentTypes { get; set; }
+    public List<ContentTypeDescriptorTopicViewModel> PermittedContentTypes { get; } = new();
 
     /*==========================================================================================================================
     | PROPERTY: IMPLICITLY PERMITTED?
diff --git a/OnTopic.Editor.Models/Metadata/NestedTopicListAttributeTopicViewModel.cs b/OnTopic.Editor.Models/Metadata/NestedTopicListAttributeTopicViewModel.cs
index 3d57f6f3..ea34eb08 100644
--- a/OnTopic.Editor.Models/Metadata/NestedTopicListAttributeTopicViewModel.cs
+++ b/OnTopic.Editor.Models/Metadata/NestedTopicListAttributeTopicViewModel.cs
@@ -47,7 +47,7 @@ public class NestedTopicListAttributeTopicViewModel: AttributeDescriptorTopicVie
     /// </summary>
     [Follow(Relationships.None)]
     [Relationship("ContentTypes", Type=RelationshipType.Relationship)]
-    public List<ContentTypeDescriptorTopicViewModel> PermittedContentTypes { get; } = new List<ContentTypeDescriptorTopicViewModel>();
+    public List<ContentTypeDescriptorTopicViewModel> PermittedContentTypes { get; } = new();
 
     /*==============================================================================================================================
     | ENABLE MODAL
diff --git a/OnTopic.Editor.Models/Metadata/NumberAttributeTopicViewModel.cs b/OnTopic.Editor.Models/Metadata/NumberAttributeTopicViewModel.cs
index 8c0bd8a9..488d40fa 100644
--- a/OnTopic.Editor.Models/Metadata/NumberAttributeTopicViewModel.cs
+++ b/OnTopic.Editor.Models/Metadata/NumberAttributeTopicViewModel.cs
@@ -23,7 +23,7 @@ public class NumberAttributeTopicViewModel: AttributeDescriptorTopicViewModel {
     /// <summary>
     ///   Determines the lower bound for acceptable values. Defaults to 0.
     /// </summary>
-    public int MinimumValue { get; set; } = 0;
+    public int MinimumValue { get; set; }
 
     /*==========================================================================================================================
     | PROPERTY: MAXIMUM VALUE
diff --git a/OnTopic.Editor.Models/OnTopic.Editor.Models.csproj b/OnTopic.Editor.Models/OnTopic.Editor.Models.csproj
index 6ffc8a6a..f976b43d 100644
--- a/OnTopic.Editor.Models/OnTopic.Editor.Models.csproj
+++ b/OnTopic.Editor.Models/OnTopic.Editor.Models.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <TargetFrameworks>netstandard2.1</TargetFrameworks>
-    <LangVersion>8.0</LangVersion>
+    <LangVersion>9.0</LangVersion>
     <AssemblyTitle>OnTopic.Editor.Models</AssemblyTitle>
     <OutputPath>bin\$(Configuration)\</OutputPath>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
@@ -23,13 +23,17 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="GitVersionTask" Version="5.3.7">
+    <PackageReference Include="GitVersionTask" Version="5.5.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="OnTopic" Version="4.5.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="3.3.1">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+    <PackageReference Include="OnTopic" Version="4.6.0" />
     <PackageReference Include="OnTopic.Data.Transfer" Version="1.2.0" />
-    <PackageReference Include="OnTopic.ViewModels" Version="4.5.0" />
+    <PackageReference Include="OnTopic.ViewModels" Version="4.6.0" />
     <PackageReference Include="System.Text.Json" Version="4.6.0" />
   </ItemGroup>
 
diff --git a/OnTopic.Editor.Models/Properties/AssemblyInfo.cs b/OnTopic.Editor.Models/Properties/AssemblyInfo.cs
index eca3fc0c..3eebea73 100644
--- a/OnTopic.Editor.Models/Properties/AssemblyInfo.cs
+++ b/OnTopic.Editor.Models/Properties/AssemblyInfo.cs
@@ -1,5 +1,4 @@
-using System.Reflection;
-using System.Runtime.CompilerServices;
+using System.Diagnostics.CodeAnalysis;
 using System.Runtime.InteropServices;
 
 // Setting ComVisible to false makes the types in this assembly not visible
@@ -9,3 +8,7 @@
 
 // The following GUID is for the ID of the typelib if this project is exposed to COM
 [assembly: Guid("02a3d98a-bf8a-4150-8fec-45a0d9c322e4")]
+
+// Handle suppressions
+[assembly: SuppressMessage("Naming", "CA1721:Property names should not match get methods", Justification = "By design", Scope = "member", Target = "~P:OnTopic.Editor.Models.Metadata.ContentTypeDescriptorTopicViewModel.AttributeDescriptors")]
+[assembly: SuppressMessage("Naming", "CA1721:Property names should not match get methods", Justification = "By design", Scope = "member", Target = "~P:OnTopic.Editor.Models.Components.BindingModels.AttributeBindingModel.Value")]
\ No newline at end of file
diff --git a/OnTopic.Editor.Models/Queryable/QueryResultTopicViewModel.cs b/OnTopic.Editor.Models/Queryable/QueryResultTopicViewModel.cs
index 9c458b04..31fd2b26 100644
--- a/OnTopic.Editor.Models/Queryable/QueryResultTopicViewModel.cs
+++ b/OnTopic.Editor.Models/Queryable/QueryResultTopicViewModel.cs
@@ -138,7 +138,7 @@ public bool IsDraggable {
     ///   Determines whether the current topic is a leaf node or not.
     /// </summary>
     [JsonPropertyName("leaf")]
-    public bool IsLeaf => Children.Count.Equals(0);
+    public bool IsLeaf => Children.Count is 0;
 
     /*==========================================================================================================================
     | IS EXPANDED?
@@ -164,7 +164,7 @@ public bool IsExpanded {
     /// <summary>
     ///   Provides a collection of child objects.
     /// </summary>
-    public List<QueryResultTopicViewModel> Children { get; } = new List<QueryResultTopicViewModel>();
+    public List<QueryResultTopicViewModel> Children { get; } = new();
 
   } // Class
 } // Namespace
\ No newline at end of file
diff --git a/OnTopic.Editor.Models/Queryable/TopicQueryOptions.cs b/OnTopic.Editor.Models/Queryable/TopicQueryOptions.cs
index 7feaa565..317b0be4 100644
--- a/OnTopic.Editor.Models/Queryable/TopicQueryOptions.cs
+++ b/OnTopic.Editor.Models/Queryable/TopicQueryOptions.cs
@@ -18,9 +18,9 @@ public class TopicQueryOptions {
     /*==========================================================================================================================
     | PRIVATE VARIABLES
     \-------------------------------------------------------------------------------------------------------------------------*/
-    bool                        _markRelated                    = false;
+    bool                        _markRelated;
     bool                        _expandRelated                  = true;
-    bool                        _showCheckboxes                 = false;
+    bool                        _showCheckboxes;
 
     /*==========================================================================================================================
     | CONSTRUCTOR
diff --git a/OnTopic.Editor.Models/Transfer/ExportViewModel.cs b/OnTopic.Editor.Models/Transfer/ExportViewModel.cs
index ff501433..61b8322a 100644
--- a/OnTopic.Editor.Models/Transfer/ExportViewModel.cs
+++ b/OnTopic.Editor.Models/Transfer/ExportViewModel.cs
@@ -21,7 +21,7 @@ public class ExportViewModel: EditorViewModel {
     /// <summary>
     ///   The <see cref="ExportOptions"/> represent the user's preference for how to export the current topic.
     /// </summary>
-    public ExportOptions ExportOptions { get; set; } = new ExportOptions();
+    public ExportOptions ExportOptions { get; set; } = new();
 
   } // Class
 } // Namespace
\ No newline at end of file
diff --git a/OnTopic.Editor.Models/Transfer/ImportViewModel.cs b/OnTopic.Editor.Models/Transfer/ImportViewModel.cs
index f826a112..81c1c2d9 100644
--- a/OnTopic.Editor.Models/Transfer/ImportViewModel.cs
+++ b/OnTopic.Editor.Models/Transfer/ImportViewModel.cs
@@ -21,7 +21,7 @@ public class ImportViewModel: EditorViewModel {
     /// <summary>
     ///   The <see cref="ImportOptions"/> represent the user's preference for how to import a serialized JSON file.
     /// </summary>
-    public ImportOptions ImportOptions { get; set; } = new ImportOptions();
+    public ImportOptions ImportOptions { get; set; } = new();
 
     /*==========================================================================================================================
     | IS IMPORTED?
@@ -29,7 +29,7 @@ public class ImportViewModel: EditorViewModel {
     /// <summary>
     ///   The <see cref="IsImported"/> property is set after the file is successfully imported.
     /// </summary>
-    public bool IsImported { get; set; } = false;
+    public bool IsImported { get; set; }
 
   } // Class
 } // Namespace
\ No newline at end of file