diff --git a/src/Umbraco.Infrastructure/Composing/UmbracoServiceProviderFactory.cs b/src/Umbraco.Infrastructure/Composing/UmbracoServiceProviderFactory.cs
index cc78577f7e..56a972a64b 100644
--- a/src/Umbraco.Infrastructure/Composing/UmbracoServiceProviderFactory.cs
+++ b/src/Umbraco.Infrastructure/Composing/UmbracoServiceProviderFactory.cs
@@ -2,7 +2,6 @@
 using LightInject.Microsoft.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection;
 using System;
-using System.Diagnostics;
 using Umbraco.Composing;
 using Umbraco.Core.Composing.LightInject;
 using Umbraco.Core.Configuration;
diff --git a/src/Umbraco.Infrastructure/Media/UploadAutoFillProperties.cs b/src/Umbraco.Infrastructure/Media/UploadAutoFillProperties.cs
index 6c338fc260..05d4744526 100644
--- a/src/Umbraco.Infrastructure/Media/UploadAutoFillProperties.cs
+++ b/src/Umbraco.Infrastructure/Media/UploadAutoFillProperties.cs
@@ -112,16 +112,16 @@ namespace Umbraco.Web.Media
             if (content == null) throw new ArgumentNullException(nameof(content));
             if (autoFillConfig == null) throw new ArgumentNullException(nameof(autoFillConfig));
 
-            if (!string.IsNullOrEmpty(autoFillConfig.WidthFieldAlias) && content.Properties.Contains(autoFillConfig.WidthFieldAlias))
+            if (!string.IsNullOrWhiteSpace(autoFillConfig.WidthFieldAlias) && content.Properties.Contains(autoFillConfig.WidthFieldAlias))
                 content.Properties[autoFillConfig.WidthFieldAlias].SetValue(size.HasValue ? size.Value.Width.ToInvariantString() : string.Empty, culture, segment);
 
-            if (!string.IsNullOrEmpty(autoFillConfig.HeightFieldAlias) && content.Properties.Contains(autoFillConfig.HeightFieldAlias))
+            if (!string.IsNullOrWhiteSpace(autoFillConfig.HeightFieldAlias) && content.Properties.Contains(autoFillConfig.HeightFieldAlias))
                 content.Properties[autoFillConfig.HeightFieldAlias].SetValue(size.HasValue ? size.Value.Height.ToInvariantString() : string.Empty, culture, segment);
 
-            if (!string.IsNullOrEmpty(autoFillConfig.LengthFieldAlias) && content.Properties.Contains(autoFillConfig.LengthFieldAlias))
+            if (!string.IsNullOrWhiteSpace(autoFillConfig.LengthFieldAlias) && content.Properties.Contains(autoFillConfig.LengthFieldAlias))
                 content.Properties[autoFillConfig.LengthFieldAlias].SetValue(length, culture, segment);
 
-            if (!string.IsNullOrEmpty(autoFillConfig.ExtensionFieldAlias) && content.Properties.Contains(autoFillConfig.ExtensionFieldAlias))
+            if (!string.IsNullOrWhiteSpace(autoFillConfig.ExtensionFieldAlias) && content.Properties.Contains(autoFillConfig.ExtensionFieldAlias))
                 content.Properties[autoFillConfig.ExtensionFieldAlias].SetValue(extension, culture, segment);
         }
 
diff --git a/src/Umbraco.Tests.Integration/TestServerTest/UmbracoTestServerTestBase.cs b/src/Umbraco.Tests.Integration/TestServerTest/UmbracoTestServerTestBase.cs
index d366ea49ee..d5c2616c6c 100644
--- a/src/Umbraco.Tests.Integration/TestServerTest/UmbracoTestServerTestBase.cs
+++ b/src/Umbraco.Tests.Integration/TestServerTest/UmbracoTestServerTestBase.cs
@@ -32,7 +32,16 @@ namespace Umbraco.Tests.Integration.TestServerTest
 
         }
 
+        /// <summary>
+        /// Get the service from the underlying container that is also used by the <see cref="Client"/>.
+        /// </summary>
         protected T GetRequiredService<T>() => Factory.Services.GetRequiredService<T>();
+
+        /// <summary>
+        /// Prepare a url before using <see cref="Client"/>.
+        /// This returns the url but also sets the HttpContext.request into to use this url.
+        /// </summary>
+        /// <returns>The string URL of the controller action.</returns>
         protected string PrepareUrl<T>(Expression<Func<T, object>> methodSelector)
             where T : UmbracoApiController
         {
diff --git a/src/Umbraco.Tests/Umbraco.Tests.csproj b/src/Umbraco.Tests/Umbraco.Tests.csproj
index a2ebdd5e66..d09c756cdd 100644
--- a/src/Umbraco.Tests/Umbraco.Tests.csproj
+++ b/src/Umbraco.Tests/Umbraco.Tests.csproj
@@ -252,7 +252,6 @@
     <Compile Include="Cache\SingleItemsOnlyCachePolicyTests.cs" />
     <Compile Include="Web\Controllers\AuthenticationControllerTests.cs" />
     <Compile Include="Web\Controllers\BackOfficeControllerUnitTests.cs" />
-    <Compile Include="Web\Controllers\ContentControllerTests.cs" />
     <Compile Include="Web\Controllers\UserEditorAuthorizationHelperTests.cs" />
     <Compile Include="Web\Controllers\UsersControllerTests.cs" />
     <Compile Include="Web\HealthChecks\HealthCheckResultsTests.cs" />
diff --git a/src/Umbraco.Tests/Web/Controllers/ContentControllerTests.cs b/src/Umbraco.Tests/Web/Controllers/ContentControllerTests.cs
deleted file mode 100644
index b92db6d4ee..0000000000
--- a/src/Umbraco.Tests/Web/Controllers/ContentControllerTests.cs
+++ /dev/null
@@ -1,518 +0,0 @@
-// using System;
-// using System.Collections.Generic;
-// using System.Globalization;
-// using System.Linq;
-// using System.Net;
-// using System.Net.Http;
-// using System.Net.Http.Headers;
-// using System.Web.Http;
-// using Moq;
-// using Newtonsoft.Json;
-// using Newtonsoft.Json.Linq;
-// using NUnit.Framework;
-// using Umbraco.Core;
-// using Umbraco.Core.Cache;
-// using Umbraco.Core.Configuration;
-// using Umbraco.Core.Dictionary;
-// using Umbraco.Core.Logging;
-// using Umbraco.Core.Models;
-// using Umbraco.Core.Models.Entities;
-// using Umbraco.Core.Models.Membership;
-// using Umbraco.Core.Persistence;
-// using Umbraco.Core.PropertyEditors;
-// using Umbraco.Core.Services;
-// using Umbraco.Tests.TestHelpers;
-// using Umbraco.Tests.TestHelpers.ControllerTesting;
-// using Umbraco.Tests.TestHelpers.Entities;
-// using Umbraco.Tests.Testing;
-// using Umbraco.Web;
-// using Umbraco.Web.Actions;
-// using Umbraco.Web.Editors;
-// using Umbraco.Web.Models.ContentEditing;
-// using Umbraco.Web.PropertyEditors;
-// using Umbraco.Web.Trees;
-// using Umbraco.Web.WebApi;
-// using Umbraco.Web.Composing;
-// using Task = System.Threading.Tasks.Task;
-// using Umbraco.Core.Mapping;
-// using Umbraco.Web.Routing;
-//
-// namespace Umbraco.Tests.Web.Controllers
-// {
-//     [TestFixture]
-//     [UmbracoTest(Database = UmbracoTestOptions.Database.None)]
-//     public class ContentControllerTests : TestWithDatabaseBase
-//     {
-//         private IContentType _contentTypeForMockedContent;
-//
-//         public override void SetUp()
-//         {
-//             base.SetUp();
-//             _contentTypeForMockedContent = null;
-//         }
-//
-//         protected override void ComposeApplication(bool withApplication)
-//         {
-//             base.ComposeApplication(withApplication);
-//
-//             //Replace with mockable services:
-//
-//             var userServiceMock = new Mock<IUserService>();
-//             userServiceMock.Setup(service => service.GetUserById(It.IsAny<int>()))
-//                 .Returns((int id) => id == 1234 ? new User(TestObjects.GetGlobalSettings(), 1234, "Test", "test@test.com", "test@test.com", "", null, new List<IReadOnlyUserGroup>(), new int[0], new int[0]) : null);
-//             userServiceMock.Setup(x => x.GetProfileById(It.IsAny<int>()))
-//                 .Returns((int id) => id == 1234 ? new User(TestObjects.GetGlobalSettings(), 1234, "Test", "test@test.com", "test@test.com", "", null, new List<IReadOnlyUserGroup>(), new int[0], new int[0]) : null);
-//             userServiceMock.Setup(service => service.GetPermissionsForPath(It.IsAny<IUser>(), It.IsAny<string>()))
-//                 .Returns(new EntityPermissionSet(123, new EntityPermissionCollection(new[]
-//                 {
-//                     new EntityPermission(0, 123, new[]
-//                     {
-//                         ActionBrowse.ActionLetter.ToString(),
-//                         ActionUpdate.ActionLetter.ToString(),
-//                         ActionPublish.ActionLetter.ToString(),
-//                         ActionNew.ActionLetter.ToString()
-//                     }),
-//                 })));
-//
-//             var entityService = new Mock<IEntityService>();
-//             entityService.Setup(x => x.GetAllPaths(UmbracoObjectTypes.Document, It.IsAny<int[]>()))
-//                 .Returns((UmbracoObjectTypes objType, int[] ids) => ids.Select(x => new TreeEntityPath { Path = $"-1,{x}", Id = x }).ToList());
-//             entityService.Setup(x => x.GetKey(It.IsAny<int>(), UmbracoObjectTypes.DataType))
-//                 .Returns((int id, UmbracoObjectTypes objType) =>
-//                 {
-//                     switch (id)
-//                     {
-//                         case Constants.DataTypes.Textbox:
-//                             return Attempt.Succeed(Constants.DataTypes.Guids.TextstringGuid);
-//                         case Constants.DataTypes.RichtextEditor:
-//                             return Attempt.Succeed(Constants.DataTypes.Guids.RichtextEditorGuid);
-//                     }
-//                     return Attempt.Fail<Guid>();
-//                 });
-//
-//
-//             var dataTypeService = new Mock<IDataTypeService>();
-//             dataTypeService.Setup(service => service.GetDataType(It.IsAny<int>()))
-//                 .Returns(Mock.Of<IDataType>(type => type.Id == 9876 && type.Name == "text"));
-//             dataTypeService.Setup(service => service.GetDataType(-87))  //the RTE
-//                 .Returns(Mock.Of<IDataType>(type => type.Id == -87 && type.Name == "Rich text" && type.Configuration == new RichTextConfiguration()));
-//
-//             var langService = new Mock<ILocalizationService>();
-//             langService.Setup(x => x.GetAllLanguages()).Returns(new[] {
-//                     Mock.Of<ILanguage>(x => x.IsoCode == "en-US"),
-//                     Mock.Of<ILanguage>(x => x.IsoCode == "es-ES"),
-//                     Mock.Of<ILanguage>(x => x.IsoCode == "fr-FR")
-//                 });
-//
-//             var textService = new Mock<ILocalizedTextService>();
-//             textService.Setup(x => x.Localize(It.IsAny<string>(), It.IsAny<CultureInfo>(), It.IsAny<IDictionary<string, string>>())).Returns("text");
-//
-//             Composition.RegisterUnique(f => Mock.Of<IContentService>());
-//             Composition.RegisterUnique(f => Mock.Of<IContentTypeService>());
-//             Composition.RegisterUnique(f => userServiceMock.Object);
-//             Composition.RegisterUnique(f => entityService.Object);
-//             Composition.RegisterUnique(f => dataTypeService.Object);
-//             Composition.RegisterUnique(f => langService.Object);
-//             Composition.RegisterUnique(f => textService.Object);
-//             Composition.RegisterUnique(f => Mock.Of<ICultureDictionaryFactory>());
-//             Composition.RegisterUnique(f => new UmbracoApiControllerTypeCollection(new Type[] {  }));
-//         }
-//
-//         private MultipartFormDataContent GetMultiPartRequestContent(string json)
-//         {
-//             var multiPartBoundary = "----WebKitFormBoundary123456789";
-//             return new MultipartFormDataContent(multiPartBoundary)
-//             {
-//                 new StringContent(json)
-//                 {
-//                     Headers =
-//                     {
-//                         ContentDisposition = new ContentDispositionHeaderValue("form-data")
-//                         {
-//                             Name = "contentItem"
-//                         }
-//                     }
-//                 }
-//             };
-//         }
-//
-//         private IContentType GetMockedContentType()
-//         {
-//             var contentType = MockedContentTypes.CreateSimpleContentType();
-//             //ensure things have ids
-//             var ids = 888;
-//             foreach (var g in contentType.CompositionPropertyGroups)
-//             {
-//                 g.Id = ids;
-//                 ids++;
-//             }
-//             foreach (var p in contentType.CompositionPropertyGroups)
-//             {
-//                 p.Id = ids;
-//                 ids++;
-//             }
-//
-//             return contentType;
-//         }
-//
-//         private IContent GetMockedContent()
-//         {
-//             if (_contentTypeForMockedContent == null)
-//             {
-//                 _contentTypeForMockedContent = GetMockedContentType();
-//                 Mock.Get(ServiceContext.ContentTypeService)
-//                     .Setup(x => x.Get(_contentTypeForMockedContent.Id))
-//                     .Returns(_contentTypeForMockedContent);
-//                 Mock.Get(ServiceContext.ContentTypeService)
-//                     .As<IContentTypeBaseService>()
-//                     .Setup(x => x.Get(_contentTypeForMockedContent.Id))
-//                     .Returns(_contentTypeForMockedContent);
-//             }
-//
-//             var content = MockedContent.CreateSimpleContent(_contentTypeForMockedContent);
-//             content.Id = 123;
-//             content.Path = "-1,123";
-//             return content;
-//         }
-//
-//         private const string PublishJsonInvariant = @"{
-//     ""id"": 123,
-//     ""contentTypeAlias"": ""page"",
-//     ""parentId"": -1,
-//     ""action"": ""save"",
-//     ""variants"": [
-//         {
-//             ""name"": ""asdf"",
-//             ""properties"": [
-//                 {
-//                     ""id"": 1,
-//                     ""alias"": ""title"",
-//                     ""value"": ""asdf""
-//                 }
-//             ],
-//             ""culture"": null,
-//             ""save"": true,
-//             ""publish"": true
-//         }
-//     ]
-// }";
-//
-//         private const string PublishJsonVariant = @"{
-//     ""id"": 123,
-//     ""contentTypeAlias"": ""page"",
-//     ""parentId"": -1,
-//     ""action"": ""save"",
-//     ""variants"": [
-//         {
-//             ""name"": ""asdf"",
-//             ""properties"": [
-//                 {
-//                     ""id"": 1,
-//                     ""alias"": ""title"",
-//                     ""value"": ""asdf""
-//                 }
-//             ],
-//             ""culture"": ""en-US"",
-//             ""save"": true,
-//             ""publish"": true
-//         },
-//         {
-//             ""name"": ""asdf"",
-//             ""properties"": [
-//                 {
-//                     ""id"": 1,
-//                     ""alias"": ""title"",
-//                     ""value"": ""asdf""
-//                 }
-//             ],
-//             ""culture"": ""fr-FR"",
-//             ""save"": true,
-//             ""publish"": true
-//         },
-//         {
-//             ""name"": ""asdf"",
-//             ""properties"": [
-//                 {
-//                     ""id"": 1,
-//                     ""alias"": ""title"",
-//                     ""value"": ""asdf""
-//                 }
-//             ],
-//             ""culture"": ""es-ES"",
-//             ""save"": true,
-//             ""publish"": true
-//         }
-//     ]
-// }";
-//
-//         /// <summary>
-//         /// Returns 404 if the content wasn't found based on the ID specified
-//         /// </summary>
-//         /// <returns></returns>
-//         [Test]
-//         public async Task PostSave_Validate_Existing_Content()
-//         {
-//             ApiController CtrlFactory(HttpRequestMessage message, IUmbracoContextAccessor umbracoContextAccessor)
-//             {
-//                 var contentServiceMock = Mock.Get(ServiceContext.ContentService);
-//                 contentServiceMock.Setup(x => x.GetById(123)).Returns(() => null); //do not find it
-//
-//                 var propertyEditorCollection = new PropertyEditorCollection(new DataEditorCollection(Enumerable.Empty<DataEditor>()));
-//
-//                 var controller = new ContentController(
-//                     Factory.GetInstance<ICultureDictionary>(),
-//                     propertyEditorCollection,
-//                     Factory.GetInstance<IGlobalSettings>(),
-//                     umbracoContextAccessor,
-//                     Factory.GetInstance<ISqlContext>(),
-//                     Factory.GetInstance<ServiceContext>(),
-//                     Factory.GetInstance<AppCaches>(),
-//                     Factory.GetInstance<IProfilingLogger>(),
-//                     Factory.GetInstance<IRuntimeState>(),
-//                     ShortStringHelper,
-//                     Factory.GetInstance<UmbracoMapper>(),
-//                     Factory.GetInstance<IPublishedUrlProvider>());
-//
-//                 return controller;
-//             }
-//
-//             var runner = new TestRunner(CtrlFactory);
-//             var response = await runner.Execute("Content", "PostSave", HttpMethod.Post,
-//                 content: GetMultiPartRequestContent(PublishJsonInvariant),
-//                 mediaTypeHeader: new MediaTypeWithQualityHeaderValue("multipart/form-data"),
-//                 assertOkResponse: false);
-//
-//             Assert.AreEqual(HttpStatusCode.NotFound, response.Item1.StatusCode);
-//             Assert.AreEqual(")]}',\n{\"Message\":\"content was not found\"}", response.Item1.Content.ReadAsStringAsync().Result);
-//
-//             //var obj = JsonConvert.DeserializeObject<PagedResult<UserDisplay>>(response.Item2);
-//             //Assert.AreEqual(0, obj.TotalItems);
-//         }
-//
-//         [Test]
-//         public async Task PostSave_Validate_At_Least_One_Variant_Flagged_For_Saving()
-//         {
-//             ApiController CtrlFactory(HttpRequestMessage message, IUmbracoContextAccessor umbracoContextAccessor)
-//             {
-//                 var propertyEditorCollection = new PropertyEditorCollection(new DataEditorCollection(Enumerable.Empty<DataEditor>()));
-//                 var controller = new ContentController(
-//                     Factory.GetInstance<ICultureDictionary>(),
-//                     propertyEditorCollection,
-//                     Factory.GetInstance<IGlobalSettings>(),
-//                     umbracoContextAccessor,
-//                     Factory.GetInstance<ISqlContext>(),
-//                     Factory.GetInstance<ServiceContext>(),
-//                     Factory.GetInstance<AppCaches>(),
-//                     Factory.GetInstance<IProfilingLogger>(),
-//                     Factory.GetInstance<IRuntimeState>(),
-//                     ShortStringHelper,
-//                     Factory.GetInstance<UmbracoMapper>(),
-//                     Factory.GetInstance<IPublishedUrlProvider>());
-//
-//                 return controller;
-//             }
-//
-//             var json = JsonConvert.DeserializeObject<JObject>(PublishJsonInvariant);
-//             //remove all save flaggs
-//             ((JArray)json["variants"])[0]["save"] = false;
-//
-//             var runner = new TestRunner(CtrlFactory);
-//             var response = await runner.Execute("Content", "PostSave", HttpMethod.Post,
-//                 content: GetMultiPartRequestContent(JsonConvert.SerializeObject(json)),
-//                 mediaTypeHeader: new MediaTypeWithQualityHeaderValue("multipart/form-data"),
-//                 assertOkResponse: false);
-//
-//             Assert.AreEqual(HttpStatusCode.NotFound, response.Item1.StatusCode);
-//             Assert.AreEqual(")]}',\n{\"Message\":\"No variants flagged for saving\"}", response.Item1.Content.ReadAsStringAsync().Result);
-//         }
-//
-//         /// <summary>
-//         /// Returns 404 if any of the posted properties dont actually exist
-//         /// </summary>
-//         /// <returns></returns>
-//         [Test]
-//         public async Task PostSave_Validate_Properties_Exist()
-//         {
-//             ApiController CtrlFactory(HttpRequestMessage message, IUmbracoContextAccessor umbracoContextAccessor)
-//             {
-//                 var contentServiceMock = Mock.Get(ServiceContext.ContentService);
-//                 contentServiceMock.Setup(x => x.GetById(123)).Returns(() => GetMockedContent());
-//
-//                 var propertyEditorCollection = new PropertyEditorCollection(new DataEditorCollection(Enumerable.Empty<DataEditor>()));
-//                 var controller = new ContentController(
-//                     Factory.GetInstance<ICultureDictionary>(),
-//                     propertyEditorCollection,
-//                     Factory.GetInstance<IGlobalSettings>(),
-//                     umbracoContextAccessor,
-//                     Factory.GetInstance<ISqlContext>(),
-//                     Factory.GetInstance<ServiceContext>(),
-//                     Factory.GetInstance<AppCaches>(),
-//                     Factory.GetInstance<IProfilingLogger>(),
-//                     Factory.GetInstance<IRuntimeState>(),
-//                     ShortStringHelper,
-//                     Factory.GetInstance<UmbracoMapper>(),
-//                     Factory.GetInstance<IPublishedUrlProvider>());
-//
-//                 return controller;
-//             }
-//
-//             var json = JsonConvert.DeserializeObject<JObject>(PublishJsonInvariant);
-//             //add a non-existent property to a variant being saved
-//             var variantProps = (JArray)json["variants"].ElementAt(0)["properties"];
-//             variantProps.Add(JObject.FromObject(new
-//             {
-//                 id = 2,
-//                 alias = "doesntExist",
-//                 value = "hello"
-//             }));
-//
-//             var runner = new TestRunner(CtrlFactory);
-//             var response = await runner.Execute("Content", "PostSave", HttpMethod.Post,
-//                 content: GetMultiPartRequestContent(JsonConvert.SerializeObject(json)),
-//                 mediaTypeHeader: new MediaTypeWithQualityHeaderValue("multipart/form-data"),
-//                 assertOkResponse: false);
-//
-//             Assert.AreEqual(HttpStatusCode.NotFound, response.Item1.StatusCode);
-//         }
-//
-//         [Test]
-//         public async Task PostSave_Simple_Invariant()
-//         {
-//             var content = GetMockedContent();
-//
-//             ApiController CtrlFactory(HttpRequestMessage message, IUmbracoContextAccessor umbracoContextAccessor)
-//             {
-//                 var contentServiceMock = Mock.Get(ServiceContext.ContentService);
-//                 contentServiceMock.Setup(x => x.GetById(123)).Returns(() => content);
-//                 contentServiceMock.Setup(x => x.Save(It.IsAny<IContent>(), It.IsAny<int>(), It.IsAny<bool>()))
-//                     .Returns(new OperationResult(OperationResultType.Success, new Core.Events.EventMessages())); //success
-//
-//                 var propertyEditorCollection = new PropertyEditorCollection(new DataEditorCollection(Enumerable.Empty<DataEditor>()));
-//                 var controller = new ContentController(
-//                     Factory.GetInstance<ICultureDictionary>(),
-//                     propertyEditorCollection,
-//                     Factory.GetInstance<IGlobalSettings>(),
-//                     umbracoContextAccessor,
-//                     Factory.GetInstance<ISqlContext>(),
-//                     Factory.GetInstance<ServiceContext>(),
-//                     Factory.GetInstance<AppCaches>(),
-//                     Factory.GetInstance<IProfilingLogger>(),
-//                     Factory.GetInstance<IRuntimeState>(),
-//                     ShortStringHelper,
-//                     Factory.GetInstance<UmbracoMapper>(),
-//                     Factory.GetInstance<IPublishedUrlProvider>());
-//
-//                 return controller;
-//             }
-//
-//             var runner = new TestRunner(CtrlFactory);
-//             var response = await runner.Execute("Content", "PostSave", HttpMethod.Post,
-//                 content: GetMultiPartRequestContent(PublishJsonInvariant),
-//                 mediaTypeHeader: new MediaTypeWithQualityHeaderValue("multipart/form-data"),
-//                 assertOkResponse: false);
-//
-//             Assert.AreEqual(HttpStatusCode.OK, response.Item1.StatusCode);
-//             var display = JsonConvert.DeserializeObject<ContentItemDisplay>(response.Item2);
-//             Assert.AreEqual(1, display.Variants.Count());
-//         }
-//
-//         [Test]
-//         public async Task PostSave_Validate_Empty_Name()
-//         {
-//             var content = GetMockedContent();
-//
-//             ApiController CtrlFactory(HttpRequestMessage message, IUmbracoContextAccessor umbracoContextAccessor)
-//             {
-//                 var contentServiceMock = Mock.Get(ServiceContext.ContentService);
-//                 contentServiceMock.Setup(x => x.GetById(123)).Returns(() => content);
-//                 contentServiceMock.Setup(x => x.Save(It.IsAny<IContent>(), It.IsAny<int>(), It.IsAny<bool>()))
-//                     .Returns(new OperationResult(OperationResultType.Success, new Core.Events.EventMessages())); //success
-//
-//                 var propertyEditorCollection = new PropertyEditorCollection(new DataEditorCollection(Enumerable.Empty<DataEditor>()));
-//                 var controller = new ContentController(
-//                     Factory.GetInstance<ICultureDictionary>(),
-//                     propertyEditorCollection,
-//                     Factory.GetInstance<IGlobalSettings>(),
-//                     umbracoContextAccessor,
-//                     Factory.GetInstance<ISqlContext>(),
-//                     Factory.GetInstance<ServiceContext>(),
-//                     Factory.GetInstance<AppCaches>(),
-//                     Factory.GetInstance<IProfilingLogger>(),
-//                     Factory.GetInstance<IRuntimeState>(),
-//                     ShortStringHelper,
-//                     Factory.GetInstance<UmbracoMapper>(),
-//                     Factory.GetInstance<IPublishedUrlProvider>()
-//                     );
-//
-//                 return controller;
-//             }
-//
-//             //clear out the name
-//             var json = JsonConvert.DeserializeObject<JObject>(PublishJsonInvariant);
-//             json["variants"].ElementAt(0)["name"] = null;
-//
-//             var runner = new TestRunner(CtrlFactory);
-//             var response = await runner.Execute("Content", "PostSave", HttpMethod.Post,
-//                 content: GetMultiPartRequestContent(JsonConvert.SerializeObject(json)),
-//                 mediaTypeHeader: new MediaTypeWithQualityHeaderValue("multipart/form-data"),
-//                 assertOkResponse: false);
-//
-//             Assert.AreEqual(HttpStatusCode.BadRequest, response.Item1.StatusCode);
-//             var display = JsonConvert.DeserializeObject<ContentItemDisplay>(response.Item2);
-//             Assert.AreEqual(1, display.Errors.Count());
-//             Assert.IsTrue(display.Errors.ContainsKey("Variants[0].Name"));
-//             //ModelState":{"Variants[0].Name":["Required"]}
-//         }
-//
-//         [Test]
-//         public async Task PostSave_Validate_Variants_Empty_Name()
-//         {
-//             var content = GetMockedContent();
-//
-//             ApiController CtrlFactory(HttpRequestMessage message, IUmbracoContextAccessor umbracoContextAccessor)
-//             {
-//                 var contentServiceMock = Mock.Get(ServiceContext.ContentService);
-//                 contentServiceMock.Setup(x => x.GetById(123)).Returns(() => content);
-//                 contentServiceMock.Setup(x => x.Save(It.IsAny<IContent>(), It.IsAny<int>(), It.IsAny<bool>()))
-//                     .Returns(new OperationResult(OperationResultType.Success, new Core.Events.EventMessages())); //success
-//
-//                 var propertyEditorCollection = new PropertyEditorCollection(new DataEditorCollection(Enumerable.Empty<DataEditor>()));
-//                 var controller = new ContentController(
-//                     Factory.GetInstance<ICultureDictionary>(),
-//                     propertyEditorCollection,
-//                     Factory.GetInstance<IGlobalSettings>(),
-//                     umbracoContextAccessor,
-//                     Factory.GetInstance<ISqlContext>(),
-//                     Factory.GetInstance<ServiceContext>(),
-//                     Factory.GetInstance<AppCaches>(),
-//                     Factory.GetInstance<IProfilingLogger>(),
-//                     Factory.GetInstance<IRuntimeState>(),
-//                     ShortStringHelper,
-//                     Factory.GetInstance<UmbracoMapper>(),
-//                     Factory.GetInstance<IPublishedUrlProvider>()
-//                     );
-//
-//                 return controller;
-//             }
-//
-//             //clear out one of the names
-//             var json = JsonConvert.DeserializeObject<JObject>(PublishJsonVariant);
-//             json["variants"].ElementAt(0)["name"] = null;
-//
-//             var runner = new TestRunner(CtrlFactory);
-//             var response = await runner.Execute("Content", "PostSave", HttpMethod.Post,
-//                 content: GetMultiPartRequestContent(JsonConvert.SerializeObject(json)),
-//                 mediaTypeHeader: new MediaTypeWithQualityHeaderValue("multipart/form-data"),
-//                 assertOkResponse: false);
-//
-//             Assert.AreEqual(HttpStatusCode.BadRequest, response.Item1.StatusCode);
-//             var display = JsonConvert.DeserializeObject<ContentItemDisplay>(response.Item2);
-//             Assert.AreEqual(2, display.Errors.Count());
-//             Assert.IsTrue(display.Errors.ContainsKey("Variants[0].Name"));
-//             Assert.IsTrue(display.Errors.ContainsKey("_content_variant_en-US_null_"));
-//         }
-//
-//         // TODO: There are SOOOOO many more tests we should write - a lot of them to do with validation
-//
-//     }
-// }
diff --git a/src/Umbraco.Web.BackOffice/Controllers/DetermineAmbiguousActionByPassingParameters.cs b/src/Umbraco.Web.BackOffice/Controllers/DetermineAmbiguousActionByPassingParameters.cs
index caa3b8348a..726d61fe80 100644
--- a/src/Umbraco.Web.BackOffice/Controllers/DetermineAmbiguousActionByPassingParameters.cs
+++ b/src/Umbraco.Web.BackOffice/Controllers/DetermineAmbiguousActionByPassingParameters.cs
@@ -15,6 +15,12 @@ using Newtonsoft.Json.Linq;
 
 namespace Umbraco.Web.BackOffice.Controllers
 {
+    /// <summary>
+    /// This method determine ambiguous controller actions by making a tryparse of the string (from request) into the type of the argument.
+    /// </summary>
+    /// <remarks>
+    /// By using this methods you are allowed to to have multiple controller actions named equally. E.g. GetById(Guid id), GetById(int id),...
+    /// </remarks>
     public class DetermineAmbiguousActionByPassingParameters : ActionMethodSelectorAttribute
     {
         private string _requestBody = null;
diff --git a/src/Umbraco.Web.BackOffice/Controllers/MediaController.cs b/src/Umbraco.Web.BackOffice/Controllers/MediaController.cs
index efe14a2c3c..21b403c9cd 100644
--- a/src/Umbraco.Web.BackOffice/Controllers/MediaController.cs
+++ b/src/Umbraco.Web.BackOffice/Controllers/MediaController.cs
@@ -215,7 +215,7 @@ namespace Umbraco.Web.BackOffice.Controllers
         /// </summary>
         /// <param name="ids"></param>
         /// <returns></returns>
-        //[FilterAllowedOutgoingMedia(typeof(IEnumerable<MediaItemDisplay>))] // TODO introduce when moved to .NET Core
+        [FilterAllowedOutgoingMedia(typeof(IEnumerable<MediaItemDisplay>))]
         public IEnumerable<MediaItemDisplay> GetByIds([FromQuery]int[] ids)
         {
             var foundMedia = _mediaService.GetByIds(ids);
@@ -259,7 +259,7 @@ namespace Umbraco.Web.BackOffice.Controllers
         /// <summary>
         /// Returns the root media objects
         /// </summary>
-        //[FilterAllowedOutgoingMedia(typeof(IEnumerable<ContentItemBasic<ContentPropertyBasic>>))] // TODO introduce when moved to .NET Core
+        [FilterAllowedOutgoingMedia(typeof(IEnumerable<ContentItemBasic<ContentPropertyBasic>>))]
         public IEnumerable<ContentItemBasic<ContentPropertyBasic>> GetRootMedia()
         {
             // TODO: Add permissions check!
diff --git a/src/Umbraco.Web.BackOffice/Filters/PrefixlessBodyModelValidatorAttribute.cs b/src/Umbraco.Web.BackOffice/Filters/PrefixlessBodyModelValidatorAttribute.cs
index a19655f8ce..36cc241976 100644
--- a/src/Umbraco.Web.BackOffice/Filters/PrefixlessBodyModelValidatorAttribute.cs
+++ b/src/Umbraco.Web.BackOffice/Filters/PrefixlessBodyModelValidatorAttribute.cs
@@ -6,6 +6,9 @@ using Microsoft.AspNetCore.Mvc.ModelBinding;
 
 namespace Umbraco.Web.BackOffice.Filters
 {
+    /// <summary>
+    /// Applying this attribute to any controller will ensure that the parameter name (prefix) is not part of the validation error keys.
+    /// </summary>
     public class PrefixlessBodyModelValidatorAttribute : TypeFilterAttribute
     {
         public PrefixlessBodyModelValidatorAttribute() : base(typeof(PrefixlessBodyModelValidatorFilter))
diff --git a/src/Umbraco.Web.BackOffice/ModelBinders/BlueprintItemBinder.cs b/src/Umbraco.Web.BackOffice/ModelBinders/BlueprintItemBinder.cs
index 0e9444ae3a..744d125bf9 100644
--- a/src/Umbraco.Web.BackOffice/ModelBinders/BlueprintItemBinder.cs
+++ b/src/Umbraco.Web.BackOffice/ModelBinders/BlueprintItemBinder.cs
@@ -10,11 +10,11 @@ namespace Umbraco.Web.BackOffice.ModelBinders
 {
     internal class BlueprintItemBinder : ContentItemBinder
     {
-        private readonly ContentService _contentService;
+        private readonly IContentService _contentService;
 
-        public BlueprintItemBinder(IJsonSerializer jsonSerializer, UmbracoMapper umbracoMapper, IContentService contentService, IContentTypeService contentTypeService, IHostingEnvironment hostingEnvironment, ContentService contentService2) : base(jsonSerializer, umbracoMapper, contentService, contentTypeService, hostingEnvironment)
+        public BlueprintItemBinder(IJsonSerializer jsonSerializer, UmbracoMapper umbracoMapper, IContentService contentService, IContentTypeService contentTypeService, IHostingEnvironment hostingEnvironment) : base(jsonSerializer, umbracoMapper, contentService, contentTypeService, hostingEnvironment)
         {
-            _contentService = contentService2;
+            _contentService = contentService;
         }
 
         protected override IContent GetExisting(ContentItemSave model)
diff --git a/src/Umbraco.Web.BackOffice/Umbraco.Web.BackOffice.csproj b/src/Umbraco.Web.BackOffice/Umbraco.Web.BackOffice.csproj
index eecac784c8..911a157223 100644
--- a/src/Umbraco.Web.BackOffice/Umbraco.Web.BackOffice.csproj
+++ b/src/Umbraco.Web.BackOffice/Umbraco.Web.BackOffice.csproj
@@ -14,7 +14,6 @@
       <PackageReference Include="Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation" Version="3.1.4" />
       <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
       <PackageReference Include="Serilog.AspNetCore" Version="3.2.0" />
-      <PackageReference Include="System.IO.Pipelines" Version="4.7.1" />
     </ItemGroup>
 
     <ItemGroup>
diff --git a/src/Umbraco.Web.Common/ApplicationModels/UmbracoApiBehaviorApplicationModelProvider.cs b/src/Umbraco.Web.Common/ApplicationModels/UmbracoApiBehaviorApplicationModelProvider.cs
index ac23516b9b..e76ae1ff6b 100644
--- a/src/Umbraco.Web.Common/ApplicationModels/UmbracoApiBehaviorApplicationModelProvider.cs
+++ b/src/Umbraco.Web.Common/ApplicationModels/UmbracoApiBehaviorApplicationModelProvider.cs
@@ -36,7 +36,6 @@ namespace Umbraco.Web.Common.ApplicationModels
             ActionModelConventions = new List<IActionModelConvention>()
             {
                 new ClientErrorResultFilterConvention(), // Ensures the responses without any body is converted into a simple json object with info instead of a string like "Status Code: 404; Not Found"
-                //new InvalidModelStateFilterConvention(), // automatically 400 responses if ModelState is invalid before hitting the controller
                 new ConsumesConstraintForFormFileParameterConvention(), // If an controller accepts files, it must accept multipart/form-data.
                 new InferParameterBindingInfoConvention(modelMetadataProvider), // no need for [FromBody] everywhere, A complex type parameter is assigned to FromBody
 
diff --git a/src/Umbraco.Web.Common/Filters/AngularJsonOnlyConfigurationAttribute.cs b/src/Umbraco.Web.Common/Filters/AngularJsonOnlyConfigurationAttribute.cs
index e185491f0e..85eb55b6d9 100644
--- a/src/Umbraco.Web.Common/Filters/AngularJsonOnlyConfigurationAttribute.cs
+++ b/src/Umbraco.Web.Common/Filters/AngularJsonOnlyConfigurationAttribute.cs
@@ -13,7 +13,6 @@ namespace Umbraco.Web.Common.Filters
     {
         public AngularJsonOnlyConfigurationAttribute() : base(typeof(AngularJsonOnlyConfigurationFilter))
         {
-            Order = -2400;
         }
 
         private class AngularJsonOnlyConfigurationFilter : IResultFilter