diff --git a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/src/ViewComponentTagHelperDescriptorFactory.cs b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/src/ViewComponentTagHelperDescriptorFactory.cs
index 06b5bed18f..795786f5b8 100644
--- a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/src/ViewComponentTagHelperDescriptorFactory.cs
+++ b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/src/ViewComponentTagHelperDescriptorFactory.cs
@@ -110,11 +110,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
             if (string.Equals(selectedMethod.Name, ViewComponentTypes.AsyncMethodName, StringComparison.Ordinal))
             {
                 // Will invoke asynchronously. Method must not return Task or Task<T>.
-                if (Equals(returnType, _taskSymbol))
+                if (SymbolEqualityComparer.Default.Equals(returnType, _taskSymbol))
                 {
                     // This is ok.
                 }
-                else if (returnType.IsGenericType && Equals(returnType.ConstructedFrom, _genericTaskSymbol))
+                else if (returnType.IsGenericType && SymbolEqualityComparer.Default.Equals(returnType.ConstructedFrom, _genericTaskSymbol))
                 {
                     // This is ok.
                 }
@@ -134,13 +134,13 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
                     method = null;
                     return false;
                 }
-                else if (Equals(returnType, _taskSymbol))
+                else if (SymbolEqualityComparer.Default.Equals(returnType, _taskSymbol))
                 {
                     diagnostic = RazorExtensionsDiagnosticFactory.CreateViewComponent_SyncMethod_CannotReturnTask(type.ToDisplayString(FullNameTypeDisplayFormat));
                     method = null;
                     return false;
                 }
-                else if (returnType.IsGenericType && Equals(returnType.ConstructedFrom, _genericTaskSymbol))
+                else if (returnType.IsGenericType && SymbolEqualityComparer.Default.Equals(returnType.ConstructedFrom, _genericTaskSymbol))
                 {
                     diagnostic = RazorExtensionsDiagnosticFactory.CreateViewComponent_SyncMethod_CannotReturnTask(type.ToDisplayString(FullNameTypeDisplayFormat));
                     method = null;
@@ -208,13 +208,13 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
         private string GetIndexerValueTypeName(IParameterSymbol parameter)
         {
             INamedTypeSymbol dictionaryType;
-            if (Equals((parameter.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol))
+            if (SymbolEqualityComparer.Default.Equals((parameter.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol))
             {
                 dictionaryType = (INamedTypeSymbol)parameter.Type;
             }
-            else if (parameter.Type.AllInterfaces.Any(s => Equals(s.ConstructedFrom, _iDictionarySymbol)))
+            else if (parameter.Type.AllInterfaces.Any(s => SymbolEqualityComparer.Default.Equals(s.ConstructedFrom, _iDictionarySymbol)))
             {
-                dictionaryType = parameter.Type.AllInterfaces.First(s => Equals(s.ConstructedFrom, _iDictionarySymbol));
+                dictionaryType = parameter.Type.AllInterfaces.First(s => SymbolEqualityComparer.Default.Equals(s.ConstructedFrom, _iDictionarySymbol));
             }
             else
             {
@@ -234,7 +234,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
 
         private string GetShortName(INamedTypeSymbol componentType)
         {
-            var viewComponentAttribute = componentType.GetAttributes().Where(a => Equals(a.AttributeClass, _viewComponentAttributeSymbol)).FirstOrDefault();
+            var viewComponentAttribute = componentType.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, _viewComponentAttributeSymbol)).FirstOrDefault();
             var name = viewComponentAttribute
                 ?.NamedArguments
                 .Where(namedArgument => string.Equals(namedArgument.Key, ViewComponentTypes.ViewComponent.Name, StringComparison.Ordinal))
diff --git a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/src/ViewComponentTypeVisitor.cs b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/src/ViewComponentTypeVisitor.cs
index 916bc60653..450e4e1557 100644
--- a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/src/ViewComponentTypeVisitor.cs
+++ b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/src/ViewComponentTypeVisitor.cs
@@ -73,7 +73,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X
                 return false;
             }
 
-            var attribute = type.GetAttributes().Where(a => Equals(a.AttributeClass, queryAttribute)).FirstOrDefault();
+            var attribute = type.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, queryAttribute)).FirstOrDefault();
 
             if (attribute != null)
             {
diff --git a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/test/LegacySectionTargetExtensionTest.cs b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/test/LegacySectionTargetExtensionTest.cs
index bef1d0718f..edf09ff60a 100644
--- a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/test/LegacySectionTargetExtensionTest.cs
+++ b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version1_X/test/LegacySectionTargetExtensionTest.cs
@@ -40,7 +40,7 @@ namespace Microsoft.AspNetCore.Razor.Language.Extensions
 ";
 
             var output = context.CodeWriter.GenerateCode();
-            Assert.Equal(expected, output);
+            Assert.Equal(expected, output, ignoreLineEndingDifferences: true);
         }
     }
 }
diff --git a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/src/ViewComponentTagHelperDescriptorFactory.cs b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/src/ViewComponentTagHelperDescriptorFactory.cs
index 75b4cd62be..ef989c3f7f 100644
--- a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/src/ViewComponentTagHelperDescriptorFactory.cs
+++ b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/src/ViewComponentTagHelperDescriptorFactory.cs
@@ -104,11 +104,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X
             if (string.Equals(selectedMethod.Name, ViewComponentTypes.AsyncMethodName, StringComparison.Ordinal))
             {
                 // Will invoke asynchronously. Method must not return Task or Task<T>.
-                if (Equals(returnType, _taskSymbol))
+                if (SymbolEqualityComparer.Default.Equals(returnType, _taskSymbol))
                 {
                     // This is ok.
                 }
-                else if (returnType.IsGenericType && Equals(returnType.ConstructedFrom, _genericTaskSymbol))
+                else if (returnType.IsGenericType && SymbolEqualityComparer.Default.Equals(returnType.ConstructedFrom, _genericTaskSymbol))
                 {
                     // This is ok.
                 }
@@ -128,13 +128,13 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X
                     method = null;
                     return false;
                 }
-                else if (Equals(returnType, _taskSymbol))
+                else if (SymbolEqualityComparer.Default.Equals(returnType, _taskSymbol))
                 {
                     diagnostic = RazorExtensionsDiagnosticFactory.CreateViewComponent_SyncMethod_CannotReturnTask(type.ToDisplayString(FullNameTypeDisplayFormat));
                     method = null;
                     return false;
                 }
-                else if (returnType.IsGenericType && Equals(returnType.ConstructedFrom, _genericTaskSymbol))
+                else if (returnType.IsGenericType && SymbolEqualityComparer.Default.Equals(returnType.ConstructedFrom, _genericTaskSymbol))
                 {
                     diagnostic = RazorExtensionsDiagnosticFactory.CreateViewComponent_SyncMethod_CannotReturnTask(type.ToDisplayString(FullNameTypeDisplayFormat));
                     method = null;
@@ -223,13 +223,13 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X
         private string GetIndexerValueTypeName(IParameterSymbol parameter)
         {
             INamedTypeSymbol dictionaryType;
-            if (Equals((parameter.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol))
+            if (SymbolEqualityComparer.Default.Equals((parameter.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol))
             {
                 dictionaryType = (INamedTypeSymbol)parameter.Type;
             }
-            else if (parameter.Type.AllInterfaces.Any(s => Equals(s.ConstructedFrom, _iDictionarySymbol)))
+            else if (parameter.Type.AllInterfaces.Any(s => SymbolEqualityComparer.Default.Equals(s.ConstructedFrom, _iDictionarySymbol)))
             {
-                dictionaryType = parameter.Type.AllInterfaces.First(s => Equals(s.ConstructedFrom, _iDictionarySymbol));
+                dictionaryType = parameter.Type.AllInterfaces.First(s => SymbolEqualityComparer.Default.Equals(s.ConstructedFrom, _iDictionarySymbol));
             }
             else
             {
@@ -249,7 +249,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X
 
         private string GetShortName(INamedTypeSymbol componentType)
         {
-            var viewComponentAttribute = componentType.GetAttributes().Where(a => Equals(a.AttributeClass, _viewComponentAttributeSymbol)).FirstOrDefault();
+            var viewComponentAttribute = componentType.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, _viewComponentAttributeSymbol)).FirstOrDefault();
             var name = viewComponentAttribute
                 ?.NamedArguments
                 .Where(namedArgument => string.Equals(namedArgument.Key, ViewComponentTypes.ViewComponent.Name, StringComparison.Ordinal))
diff --git a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/src/ViewComponentTypeVisitor.cs b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/src/ViewComponentTypeVisitor.cs
index 0281880866..1d7463884c 100644
--- a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/src/ViewComponentTypeVisitor.cs
+++ b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/src/ViewComponentTypeVisitor.cs
@@ -75,7 +75,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X
                 return false;
             }
 
-            var attribute = type.GetAttributes().Where(a => Equals(a.AttributeClass, queryAttribute)).FirstOrDefault();
+            var attribute = type.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, queryAttribute)).FirstOrDefault();
 
             if (attribute != null)
             {
diff --git a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/test/RazorPageDocumentClassifierPassTest.cs b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/test/RazorPageDocumentClassifierPassTest.cs
index 8e9f111579..d86e144c78 100644
--- a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/test/RazorPageDocumentClassifierPassTest.cs
+++ b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X/test/RazorPageDocumentClassifierPassTest.cs
@@ -82,7 +82,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X
             // Arrange
             var content = @"
 @* some comment *@
-     
+
 @page
 ";
             var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create(content, "Test.cshtml"));
@@ -363,7 +363,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.Version2_X
         {
             PageDirective.Register(builder);
         }
-        
+
         private static DocumentIntermediateNode CreateIRDocument(RazorEngine engine, RazorCodeDocument codeDocument)
         {
             for (var i = 0; i < engine.Phases.Count; i++)
diff --git a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/src/ViewComponentTagHelperDescriptorFactory.cs b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/src/ViewComponentTagHelperDescriptorFactory.cs
index aaa765fb63..c266d7541d 100644
--- a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/src/ViewComponentTagHelperDescriptorFactory.cs
+++ b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/src/ViewComponentTagHelperDescriptorFactory.cs
@@ -104,11 +104,11 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
             if (string.Equals(selectedMethod.Name, ViewComponentTypes.AsyncMethodName, StringComparison.Ordinal))
             {
                 // Will invoke asynchronously. Method must not return Task or Task<T>.
-                if (Equals(returnType, _taskSymbol))
+                if (SymbolEqualityComparer.Default.Equals(returnType, _taskSymbol))
                 {
                     // This is ok.
                 }
-                else if (returnType.IsGenericType && Equals(returnType.ConstructedFrom, _genericTaskSymbol))
+                else if (returnType.IsGenericType && SymbolEqualityComparer.Default.Equals(returnType.ConstructedFrom, _genericTaskSymbol))
                 {
                     // This is ok.
                 }
@@ -128,13 +128,13 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
                     method = null;
                     return false;
                 }
-                else if (Equals(returnType, _taskSymbol))
+                else if (SymbolEqualityComparer.Default.Equals(returnType, _taskSymbol))
                 {
                     diagnostic = RazorExtensionsDiagnosticFactory.CreateViewComponent_SyncMethod_CannotReturnTask(type.ToDisplayString(FullNameTypeDisplayFormat));
                     method = null;
                     return false;
                 }
-                else if (returnType.IsGenericType && Equals(returnType.ConstructedFrom, _genericTaskSymbol))
+                else if (returnType.IsGenericType && SymbolEqualityComparer.Default.Equals(returnType.ConstructedFrom, _genericTaskSymbol))
                 {
                     diagnostic = RazorExtensionsDiagnosticFactory.CreateViewComponent_SyncMethod_CannotReturnTask(type.ToDisplayString(FullNameTypeDisplayFormat));
                     method = null;
@@ -223,13 +223,13 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
         private string GetIndexerValueTypeName(IParameterSymbol parameter)
         {
             INamedTypeSymbol dictionaryType;
-            if (Equals((parameter.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol))
+            if (SymbolEqualityComparer.Default.Equals((parameter.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol))
             {
                 dictionaryType = (INamedTypeSymbol)parameter.Type;
             }
-            else if (parameter.Type.AllInterfaces.Any(s => Equals(s.ConstructedFrom, _iDictionarySymbol)))
+            else if (parameter.Type.AllInterfaces.Any(s => SymbolEqualityComparer.Default.Equals(s.ConstructedFrom, _iDictionarySymbol)))
             {
-                dictionaryType = parameter.Type.AllInterfaces.First(s => Equals(s.ConstructedFrom, _iDictionarySymbol));
+                dictionaryType = parameter.Type.AllInterfaces.First(s => SymbolEqualityComparer.Default.Equals(s.ConstructedFrom, _iDictionarySymbol));
             }
             else
             {
@@ -249,7 +249,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
 
         private string GetShortName(INamedTypeSymbol componentType)
         {
-            var viewComponentAttribute = componentType.GetAttributes().Where(a => Equals(a.AttributeClass, _viewComponentAttributeSymbol)).FirstOrDefault();
+            var viewComponentAttribute = componentType.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, _viewComponentAttributeSymbol)).FirstOrDefault();
             var name = viewComponentAttribute
                 ?.NamedArguments
                 .Where(namedArgument => string.Equals(namedArgument.Key, ViewComponentTypes.ViewComponent.Name, StringComparison.Ordinal))
diff --git a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/src/ViewComponentTypeVisitor.cs b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/src/ViewComponentTypeVisitor.cs
index 498b28fdc2..8c7a3b4065 100644
--- a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/src/ViewComponentTypeVisitor.cs
+++ b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/src/ViewComponentTypeVisitor.cs
@@ -75,7 +75,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
                 return false;
             }
 
-            var attribute = type.GetAttributes().Where(a => Equals(a.AttributeClass, queryAttribute)).FirstOrDefault();
+            var attribute = type.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, queryAttribute)).FirstOrDefault();
 
             if (attribute != null)
             {
diff --git a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/test/RazorPageDocumentClassifierPassTest.cs b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/test/RazorPageDocumentClassifierPassTest.cs
index 286edb49bf..c66ac3d4e0 100644
--- a/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/test/RazorPageDocumentClassifierPassTest.cs
+++ b/src/Razor/Microsoft.AspNetCore.Mvc.Razor.Extensions/test/RazorPageDocumentClassifierPassTest.cs
@@ -82,7 +82,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
             // Arrange
             var content = @"
 @* some comment *@
-     
+
 @page
 ";
             var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create(content, "Test.cshtml"));
diff --git a/src/Razor/Microsoft.AspNetCore.Razor.Language/src/ClassifiedSpanVisitor.cs b/src/Razor/Microsoft.AspNetCore.Razor.Language/src/ClassifiedSpanVisitor.cs
index 81edb96152..f162744130 100644
--- a/src/Razor/Microsoft.AspNetCore.Razor.Language/src/ClassifiedSpanVisitor.cs
+++ b/src/Razor/Microsoft.AspNetCore.Razor.Language/src/ClassifiedSpanVisitor.cs
@@ -18,6 +18,11 @@ namespace Microsoft.AspNetCore.Razor.Language
 
         public ClassifiedSpanVisitor(RazorSourceDocument source)
         {
+            if (source is null)
+            {
+                throw new ArgumentNullException(nameof(source));
+            }
+
             _source = source;
             _spans = new List<ClassifiedSpanInternal>();
             _currentBlockKind = BlockKindInternal.Markup;
diff --git a/src/Razor/Microsoft.AspNetCore.Razor.Language/test/Components/ComponentMarkupBlockPassTest.cs b/src/Razor/Microsoft.AspNetCore.Razor.Language/test/Components/ComponentMarkupBlockPassTest.cs
index ca9885009a..365b7909f9 100644
--- a/src/Razor/Microsoft.AspNetCore.Razor.Language/test/Components/ComponentMarkupBlockPassTest.cs
+++ b/src/Razor/Microsoft.AspNetCore.Razor.Language/test/Components/ComponentMarkupBlockPassTest.cs
@@ -28,7 +28,7 @@ namespace Microsoft.AspNetCore.Razor.Language.Components
 
             Pass.Engine = Engine;
         }
-        
+
         private DefaultRazorProjectEngine ProjectEngine { get; }
 
         private RazorEngine Engine { get; }
@@ -81,7 +81,7 @@ namespace Microsoft.AspNetCore.Razor.Language.Components
             Assert.Equal(expected, block.Content, ignoreLineEndingDifferences: true);
         }
 
-        // See: https://github.com/aspnet/AspNetCore/issues/6480
+        // See: https://github.com/dotnet/aspnetcore/issues/6480
         [Fact]
         public void Execute_RewritesHtml_HtmlAttributePrefix()
         {
diff --git a/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentCodeGenerationTestBase.cs b/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentCodeGenerationTestBase.cs
index 1fde6741b2..b9fb0e4020 100644
--- a/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentCodeGenerationTestBase.cs
+++ b/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentCodeGenerationTestBase.cs
@@ -5120,7 +5120,7 @@ namespace Test
             CompileToAssembly(generated);
         }
 
-        [Fact] // https://github.com/aspnet/Blazor/issues/597
+        [Fact] // https://github.com/dotnet/blazor/issues/597
         public void Regression_597()
         {
             // Arrange
@@ -5186,7 +5186,7 @@ namespace Test
             CompileToAssembly(generated);
         }
 
-        [Fact] // https://github.com/aspnet/Blazor/issues/772
+        [Fact] // https://github.com/dotnet/blazor/issues/772
         public void Regression_772()
         {
             // Arrange
@@ -5224,7 +5224,7 @@ Welcome to your new app.
                 d => Assert.Equal("RZ1035", d.Id));
         }
 
-        [Fact] // https://github.com/aspnet/Blazor/issues/773
+        [Fact] // https://github.com/dotnet/blazor/issues/773
         public void Regression_773()
         {
             // Arrange
diff --git a/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentDeclarationIntegrationTest.cs b/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentDeclarationIntegrationTest.cs
index 94425c895b..8e9215906e 100644
--- a/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentDeclarationIntegrationTest.cs
+++ b/src/Razor/Microsoft.AspNetCore.Razor.Language/test/IntegrationTests/ComponentDeclarationIntegrationTest.cs
@@ -95,7 +95,7 @@ namespace Microsoft.AspNetCore.Razor.Language.IntegrationTests
             Assert.Contains(typeof(IDoCoolThings), component.GetType().GetInterfaces());
         }
 
-        [Fact] // Regression test for https://github.com/aspnet/Blazor/issues/453
+        [Fact] // Regression test for https://github.com/dotnet/blazor/issues/453
         public void DeclarationConfiguration_FunctionsBlockHasLineMappings_MappingsApplyToError()
         {
             // Arrange & Act 1
diff --git a/src/Razor/Microsoft.AspNetCore.Razor.Language/test/Microsoft.AspNetCore.Razor.Language.Test.csproj b/src/Razor/Microsoft.AspNetCore.Razor.Language/test/Microsoft.AspNetCore.Razor.Language.Test.csproj
index abdd61a8fd..120eee7bb4 100644
--- a/src/Razor/Microsoft.AspNetCore.Razor.Language/test/Microsoft.AspNetCore.Razor.Language.Test.csproj
+++ b/src/Razor/Microsoft.AspNetCore.Razor.Language/test/Microsoft.AspNetCore.Razor.Language.Test.csproj
@@ -23,7 +23,6 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Testing" Version="$(MicrosoftAspNetCoreTestingPackageVersion)" />
     <PackageReference Include="Moq" Version="$(MoqPackageVersion)" />
-    <PackageReference Include="Newtonsoft.Json" Version="$(TEST_NewtonsoftJsonPackageVersion)" />
   </ItemGroup>
 
 </Project>
diff --git a/src/Razor/Microsoft.AspNetCore.Razor.Tools/src/Microsoft.AspNetCore.Razor.Tools.csproj b/src/Razor/Microsoft.AspNetCore.Razor.Tools/src/Microsoft.AspNetCore.Razor.Tools.csproj
index 5a08e5c723..a7a3a4d347 100644
--- a/src/Razor/Microsoft.AspNetCore.Razor.Tools/src/Microsoft.AspNetCore.Razor.Tools.csproj
+++ b/src/Razor/Microsoft.AspNetCore.Razor.Tools/src/Microsoft.AspNetCore.Razor.Tools.csproj
@@ -7,7 +7,7 @@
       This is intentionally targeting netcoreapp3.0. This allows using the Microsoft.NET.Sdk.Razor package without having to solve diamond dependency problems in AspNetCore.
       We use a runtimeconfig.json.template to allow roll forwards.
       In addition, the SDK stamps an exact version of the shared fx to use in all runtimeconfig.json that are contained in the SDK.
-      See the discussion here: https://github.com/aspnet/AspNetCore-Internal/issues/3201#issuecomment-539631557
+      See the discussion here: https://github.com/dotnet/aspnetcore-internal/issues/3201#issuecomment-539631557
     -->
     <TargetFramework>netcoreapp3.0</TargetFramework>
     <OutputType>Exe</OutputType>
diff --git a/src/Razor/Microsoft.AspNetCore.Razor.Tools/test/DefaultExtensionAssemblyLoaderTest.cs b/src/Razor/Microsoft.AspNetCore.Razor.Tools/test/DefaultExtensionAssemblyLoaderTest.cs
index ad619e5570..2997bd08b3 100644
--- a/src/Razor/Microsoft.AspNetCore.Razor.Tools/test/DefaultExtensionAssemblyLoaderTest.cs
+++ b/src/Razor/Microsoft.AspNetCore.Razor.Tools/test/DefaultExtensionAssemblyLoaderTest.cs
@@ -121,7 +121,7 @@ Delta: Gamma: Beta: Test B
 
                 var actual = builder.ToString();
 
-                Assert.Equal(expected, actual);
+                Assert.Equal(expected, actual, ignoreLineEndingDifferences: true);
             }
         }
     }
diff --git a/src/Razor/Microsoft.CodeAnalysis.Razor/src/BindTagHelperDescriptorProvider.cs b/src/Razor/Microsoft.CodeAnalysis.Razor/src/BindTagHelperDescriptorProvider.cs
index e21332c150..05dea796a6 100644
--- a/src/Razor/Microsoft.CodeAnalysis.Razor/src/BindTagHelperDescriptorProvider.cs
+++ b/src/Razor/Microsoft.CodeAnalysis.Razor/src/BindTagHelperDescriptorProvider.cs
@@ -235,7 +235,7 @@ namespace Microsoft.CodeAnalysis.Razor
 
                     // We need to check the constructor argument length here, because this can show up as 0
                     // if the language service fails to initialize. This is an invalid case, so skip it.
-                    if (Equals(attribute.AttributeClass, bindElement) && attribute.ConstructorArguments.Length == 4)
+                    if (SymbolEqualityComparer.Default.Equals(attribute.AttributeClass, bindElement) && attribute.ConstructorArguments.Length == 4)
                     {
                         results.Add(new ElementBindData(
                             type.ContainingAssembly.Name,
@@ -246,7 +246,7 @@ namespace Microsoft.CodeAnalysis.Razor
                             (string)attribute.ConstructorArguments[2].Value,
                             (string)attribute.ConstructorArguments[3].Value));
                     }
-                    else if (Equals(attribute.AttributeClass, bindInputElement) && attribute.ConstructorArguments.Length == 4)
+                    else if (SymbolEqualityComparer.Default.Equals(attribute.AttributeClass, bindInputElement) && attribute.ConstructorArguments.Length == 4)
                     {
                         results.Add(new ElementBindData(
                             type.ContainingAssembly.Name,
@@ -257,7 +257,7 @@ namespace Microsoft.CodeAnalysis.Razor
                             (string)attribute.ConstructorArguments[2].Value,
                             (string)attribute.ConstructorArguments[3].Value));
                     }
-                    else if (Equals(attribute.AttributeClass, bindInputElement) && attribute.ConstructorArguments.Length == 6)
+                    else if (SymbolEqualityComparer.Default.Equals(attribute.AttributeClass, bindInputElement) && attribute.ConstructorArguments.Length == 6)
                     {
                         results.Add(new ElementBindData(
                             type.ContainingAssembly.Name,
diff --git a/src/Razor/Microsoft.CodeAnalysis.Razor/src/ComponentTagHelperDescriptorProvider.cs b/src/Razor/Microsoft.CodeAnalysis.Razor/src/ComponentTagHelperDescriptorProvider.cs
index ebc1947ca7..38fbfb6ba8 100644
--- a/src/Razor/Microsoft.CodeAnalysis.Razor/src/ComponentTagHelperDescriptorProvider.cs
+++ b/src/Razor/Microsoft.CodeAnalysis.Razor/src/ComponentTagHelperDescriptorProvider.cs
@@ -301,6 +301,7 @@ namespace Microsoft.CodeAnalysis.Razor
                 b.Name = ComponentMetadata.ChildContent.ParameterAttributeName;
                 b.TypeName = typeof(string).FullName;
                 b.Metadata.Add(ComponentMetadata.Component.ChildContentParameterNameKey, bool.TrueString);
+                b.Metadata.Add(TagHelperMetadata.Common.PropertyName, b.Name);
 
                 if (childContentName == null)
                 {
@@ -327,7 +328,7 @@ namespace Microsoft.CodeAnalysis.Razor
             var properties = new Dictionary<string, (IPropertySymbol, PropertyKind)>(StringComparer.Ordinal);
             do
             {
-                if (Equals(type, symbols.ComponentBase))
+                if (SymbolEqualityComparer.Default.Equals(type, symbols.ComponentBase))
                 {
                     // The ComponentBase base class doesn't have any [Parameter].
                     // Bail out now to avoid walking through its many members, plus the members
@@ -380,7 +381,7 @@ namespace Microsoft.CodeAnalysis.Razor
                         kind = PropertyKind.Ignored;
                     }
 
-                    if (!property.GetAttributes().Any(a => Equals(a.AttributeClass, symbols.ParameterAttribute)))
+                    if (!property.GetAttributes().Any(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, symbols.ParameterAttribute)))
                     {
                         if (property.IsOverride)
                         {
@@ -398,7 +399,7 @@ namespace Microsoft.CodeAnalysis.Razor
                         kind = PropertyKind.Enum;
                     }
 
-                    if (kind == PropertyKind.Default && Equals(property.Type, symbols.RenderFragment))
+                    if (kind == PropertyKind.Default && SymbolEqualityComparer.Default.Equals(property.Type, symbols.RenderFragment))
                     {
                         kind = PropertyKind.ChildContent;
                     }
@@ -406,12 +407,12 @@ namespace Microsoft.CodeAnalysis.Razor
                     if (kind == PropertyKind.Default &&
                         property.Type is INamedTypeSymbol namedType &&
                         namedType.IsGenericType &&
-                        Equals(namedType.ConstructedFrom, symbols.RenderFragmentOfT))
+                        SymbolEqualityComparer.Default.Equals(namedType.ConstructedFrom, symbols.RenderFragmentOfT))
                     {
                         kind = PropertyKind.ChildContent;
                     }
 
-                    if (kind == PropertyKind.Default && Equals(property.Type, symbols.EventCallback))
+                    if (kind == PropertyKind.Default && SymbolEqualityComparer.Default.Equals(property.Type, symbols.EventCallback))
                     {
                         kind = PropertyKind.EventCallback;
                     }
@@ -419,7 +420,7 @@ namespace Microsoft.CodeAnalysis.Razor
                     if (kind == PropertyKind.Default &&
                         property.Type is INamedTypeSymbol namedType2 &&
                         namedType2.IsGenericType &&
-                        Equals(namedType2.ConstructedFrom, symbols.EventCallbackOfT))
+                        SymbolEqualityComparer.Default.Equals(namedType2.ConstructedFrom, symbols.EventCallbackOfT))
                     {
                         kind = PropertyKind.EventCallback;
                     }
diff --git a/src/Razor/Microsoft.CodeAnalysis.Razor/src/DefaultTagHelperDescriptorFactory.cs b/src/Razor/Microsoft.CodeAnalysis.Razor/src/DefaultTagHelperDescriptorFactory.cs
index 17924a0018..4eb83b36b7 100644
--- a/src/Razor/Microsoft.CodeAnalysis.Razor/src/DefaultTagHelperDescriptorFactory.cs
+++ b/src/Razor/Microsoft.CodeAnalysis.Razor/src/DefaultTagHelperDescriptorFactory.cs
@@ -80,7 +80,7 @@ namespace Microsoft.CodeAnalysis.Razor
         {
             var targetElementAttributes = type
                 .GetAttributes()
-                .Where(attribute => Equals(attribute.AttributeClass, _htmlTargetElementAttributeSymbol));
+                .Where(attribute => SymbolEqualityComparer.Default.Equals(attribute.AttributeClass, _htmlTargetElementAttributeSymbol));
 
             // If there isn't an attribute specifying the tag name derive it from the name
             if (!targetElementAttributes.Any())
@@ -139,7 +139,7 @@ namespace Microsoft.CodeAnalysis.Razor
 
         private void AddAllowedChildren(INamedTypeSymbol type, TagHelperDescriptorBuilder builder)
         {
-            var restrictChildrenAttribute = type.GetAttributes().Where(a => Equals(a.AttributeClass, _restrictChildrenAttributeSymbol)).FirstOrDefault();
+            var restrictChildrenAttribute = type.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, _restrictChildrenAttributeSymbol)).FirstOrDefault();
             if (restrictChildrenAttribute == null)
             {
                 return;
@@ -174,7 +174,7 @@ namespace Microsoft.CodeAnalysis.Razor
         private void AddTagOutputHint(INamedTypeSymbol type, TagHelperDescriptorBuilder builder)
         {
             string outputElementHint = null;
-            var outputElementHintAttribute = type.GetAttributes().Where(a => Equals(a.AttributeClass, _outputElementHintAttributeSymbol)).FirstOrDefault();
+            var outputElementHintAttribute = type.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, _outputElementHintAttributeSymbol)).FirstOrDefault();
             if (outputElementHintAttribute != null)
             {
                 outputElementHint = (string)(outputElementHintAttribute.ConstructorArguments[0]).Value;
@@ -189,7 +189,7 @@ namespace Microsoft.CodeAnalysis.Razor
         {
             var attributeNameAttribute = property
                 .GetAttributes()
-                .Where(a => Equals(a.AttributeClass, _htmlAttributeNameAttributeSymbol))
+                .Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, _htmlAttributeNameAttributeSymbol))
                 .FirstOrDefault();
 
             bool hasExplicitName;
@@ -310,13 +310,13 @@ namespace Microsoft.CodeAnalysis.Razor
         private IReadOnlyList<ITypeSymbol> GetDictionaryArgumentTypes(IPropertySymbol property)
         {
             INamedTypeSymbol dictionaryType;
-            if (Equals((property.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol))
+            if (SymbolEqualityComparer.Default.Equals((property.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol))
             {
                 dictionaryType = (INamedTypeSymbol)property.Type;
             }
-            else if (property.Type.AllInterfaces.Any(s => Equals(s.ConstructedFrom, _iDictionarySymbol)))
+            else if (property.Type.AllInterfaces.Any(s => SymbolEqualityComparer.Default.Equals(s.ConstructedFrom, _iDictionarySymbol)))
             {
-                dictionaryType = property.Type.AllInterfaces.First(s => Equals(s.ConstructedFrom, _iDictionarySymbol));
+                dictionaryType = property.Type.AllInterfaces.First(s => SymbolEqualityComparer.Default.Equals(s.ConstructedFrom, _iDictionarySymbol));
             }
             else
             {
@@ -380,7 +380,7 @@ namespace Microsoft.CodeAnalysis.Razor
         private bool IsPotentialDictionaryProperty(IPropertySymbol property)
         {
             return
-                (Equals((property.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol) || property.Type.AllInterfaces.Any(s => Equals(s.ConstructedFrom, _iDictionarySymbol))) &&
+                (SymbolEqualityComparer.Default.Equals((property.Type as INamedTypeSymbol)?.ConstructedFrom, _iDictionarySymbol) || property.Type.AllInterfaces.Any(s => SymbolEqualityComparer.Default.Equals(s.ConstructedFrom, _iDictionarySymbol))) &&
                 GetDictionaryArgumentTypes(property)?[0].SpecialType == SpecialType.System_String;
         }
 
@@ -397,8 +397,8 @@ namespace Microsoft.CodeAnalysis.Razor
                         property.Parameters.Length == 0 &&
                         property.GetMethod != null &&
                         property.GetMethod.DeclaredAccessibility == Accessibility.Public &&
-                        property.GetAttributes().Where(a => Equals(a.AttributeClass, _htmlAttributeNotBoundAttributeSymbol)).FirstOrDefault() == null &&
-                        (property.GetAttributes().Any(a => Equals(a.AttributeClass, _htmlAttributeNameAttributeSymbol)) ||
+                        property.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, _htmlAttributeNotBoundAttributeSymbol)).FirstOrDefault() == null &&
+                        (property.GetAttributes().Any(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, _htmlAttributeNameAttributeSymbol)) ||
                         property.SetMethod != null && property.SetMethod.DeclaredAccessibility == Accessibility.Public ||
                         IsPotentialDictionaryProperty(property)) &&
                         !accessibleProperties.ContainsKey(property.Name))
@@ -418,7 +418,7 @@ namespace Microsoft.CodeAnalysis.Razor
         {
             if (ExcludeHidden)
             {
-                var editorBrowsableAttribute = symbol.GetAttributes().Where(a => Equals(a.AttributeClass, _editorBrowsableAttributeSymbol)).FirstOrDefault();
+                var editorBrowsableAttribute = symbol.GetAttributes().Where(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, _editorBrowsableAttributeSymbol)).FirstOrDefault();
 
                 if (editorBrowsableAttribute == null)
                 {
diff --git a/src/Razor/Microsoft.CodeAnalysis.Razor/src/EventHandlerTagHelperDescriptorProvider.cs b/src/Razor/Microsoft.CodeAnalysis.Razor/src/EventHandlerTagHelperDescriptorProvider.cs
index 5522b50163..9f5cf0d20a 100644
--- a/src/Razor/Microsoft.CodeAnalysis.Razor/src/EventHandlerTagHelperDescriptorProvider.cs
+++ b/src/Razor/Microsoft.CodeAnalysis.Razor/src/EventHandlerTagHelperDescriptorProvider.cs
@@ -81,7 +81,7 @@ namespace Microsoft.CodeAnalysis.Razor
                 {
                     var attribute = attributes[j];
 
-                    if (Equals(attribute.AttributeClass, eventHandlerAttribute))
+                    if (SymbolEqualityComparer.Default.Equals(attribute.AttributeClass, eventHandlerAttribute))
                     {
                         var enablePreventDefault = false;
                         var enableStopPropagation = false;
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/src/build/netstandard2.0/Sdk.Razor.CurrentVersion.targets b/src/Razor/Microsoft.NET.Sdk.Razor/src/build/netstandard2.0/Sdk.Razor.CurrentVersion.targets
index e5e8d926a0..dfee69656f 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/src/build/netstandard2.0/Sdk.Razor.CurrentVersion.targets
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/src/build/netstandard2.0/Sdk.Razor.CurrentVersion.targets
@@ -30,7 +30,7 @@ Copyright (c) .NET Foundation. All rights reserved.
     <!-- Paths to tools, tasks, and extensions are calculated relative to the RazorSdkDirectoryRoot. This can be modified to test a local build. -->
     <RazorSdkDirectoryRoot Condition="'$(RazorSdkDirectoryRoot)'==''">$(MSBuildThisFileDirectory)..\..\</RazorSdkDirectoryRoot>
     <RazorSdkBuildTasksDirectoryRoot Condition="'$(RazorSdkBuildTasksDirectoryRoot)'==''">$(RazorSdkDirectoryRoot)tasks\</RazorSdkBuildTasksDirectoryRoot>
-    <_RazorSdkTasksTFM Condition=" '$(MSBuildRuntimeType)' == 'Core'">netcoreapp3.1</_RazorSdkTasksTFM>
+    <_RazorSdkTasksTFM Condition=" '$(MSBuildRuntimeType)' == 'Core'">netcoreapp5.0</_RazorSdkTasksTFM>
     <_RazorSdkTasksTFM Condition=" '$(_RazorSdkTasksTFM)' == ''">net46</_RazorSdkTasksTFM>
     <RazorSdkBuildTasksAssembly>$(RazorSdkBuildTasksDirectoryRoot)$(_RazorSdkTasksTFM)\Microsoft.NET.Sdk.Razor.Tasks.dll</RazorSdkBuildTasksAssembly>
   </PropertyGroup>
@@ -516,7 +516,7 @@ Copyright (c) .NET Foundation. All rights reserved.
   </Target>
 
   <!--
-    Temporarary workaround for https://github.com/aspnet/AspNetCore/issues/6859. This can be removed after a VS insertion with a newer copy of the DesignTime targets.
+    Temporarary workaround for https://github.com/dotnet/aspnetcore/issues/6859. This can be removed after a VS insertion with a newer copy of the DesignTime targets.
   -->
   <ItemGroup>
     <Content Update="$(_RazorComponentInclude)">
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/BuildVariables.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/BuildVariables.cs
index 1373497c3e..d213b173c1 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/BuildVariables.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/BuildVariables.cs
@@ -6,7 +6,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
     internal static partial class BuildVariables
     {
         private static string _msBuildPath = string.Empty;
-        private static string _microsoftNETCoreApp31PackageVersion = string.Empty;
+        private static string _MicrosoftNETCoreApp50PackageVersion = string.Empty;
         private static string _microsoftNetCompilersToolsetPackageVersion = string.Empty;
 
         static partial void InitializeVariables();
@@ -20,12 +20,12 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             }
         }
 
-        public static string MicrosoftNETCoreApp31PackageVersion
+        public static string MicrosoftNETCoreApp50PackageVersion
         {
             get
             {
                 InitializeVariables();
-                return _microsoftNETCoreApp31PackageVersion;
+                return _MicrosoftNETCoreApp50PackageVersion;
             }
         }
 
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/ApplicationPartDiscoveryIntegrationTest.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/ApplicationPartDiscoveryIntegrationTest.cs
index 91a7fd89f6..f258b6eaa1 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/ApplicationPartDiscoveryIntegrationTest.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/ApplicationPartDiscoveryIntegrationTest.cs
@@ -97,7 +97,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             }
         }
 
-        // Regression test for https://github.com/aspnet/AspNetCore/issues/11315
+        // Regression test for https://github.com/dotnet/aspnetcore/issues/11315
         [Fact]
         [InitializeTestProject("AppWithP2PReference", additionalProjects: "ClassLibrary")]
         public async Task BuildIncrementalism_CausingRecompilation_WhenApplicationPartAttributeIsGenerated()
@@ -123,7 +123,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             Assert.AssemblyHasAttribute(result, Path.Combine(OutputPath, "AppWithP2PReference.dll"), "Microsoft.AspNetCore.Mvc.ApplicationParts.ApplicationPartAttribute");
         }
 
-        [Fact]
+        [Fact(Skip = "https://github.com/dotnet/aspnetcore/issues/13303")]
         [InitializeTestProject("SimpleMvcFSharp", language: "F#", additionalProjects: "ClassLibrary")]
         public async Task Build_ProjectWithDependencyThatReferencesMvc_AddsAttributeToNonCSharpProjects()
         {
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/BuildIntegrationTest.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/BuildIntegrationTest.cs
index 6ccfae6bf0..598f21c93b 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/BuildIntegrationTest.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/BuildIntegrationTest.cs
@@ -472,7 +472,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             Assert.FileDoesNotContain(result, razorAssemblyInfo, "Microsoft.AspNetCore.Razor.Hosting.RazorConfigurationNameAttribute");
         }
 
-        [Fact]
+        [Fact(Skip = "https://github.com/dotnet/aspnetcore/issues/13303")]
         [InitializeTestProject("SimpleMvcFSharp", language: "F#")]
         public async Task Build_SimpleMvcFSharp_NoopsWithoutFailing()
         {
@@ -639,13 +639,15 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             Assert.FileDoesNotExist(result, IntermediateOutputPath, "SimpleMvc.Views.dll");
         }
 
-        [Fact(Skip = "Default C# version is 7.3 for netcoreapp3.1 and later https://github.com/aspnet/AspNetCore/issues/13930")]
+        [Fact(Skip = "Default C# version is 7.3 for netcoreapp3.1 and later https://github.com/dotnet/aspnetcore/issues/13930")]
         [InitializeTestProject("SimpleMvc")]
         public async Task Build_ImplicitCSharp8_NullableEnforcement_WarningsDuringBuild_NoBuildServer()
         {
             var result = await DotnetMSBuild(
                 "Build",
-                "/p:Nullable=enable",
+                // Remove /p:LangVersion=Default once we've picked up a compiler that supports .NET 5.0.
+                // Tracked by https://github.com/dotnet/aspnetcore/issues/13304
+                "/p:Nullable=enable /p:LangVersion=Default",
                 suppressBuildServer: true);
             var indexFilePath = Path.Combine(RazorIntermediateOutputPath, "Views", "Home", "Index.cshtml.g.cs");
 
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/BuildIntrospectionTest.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/BuildIntrospectionTest.cs
index acff14237e..2e894fce62 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/BuildIntrospectionTest.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/BuildIntrospectionTest.cs
@@ -215,7 +215,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
         [InitializeTestProject("SimpleMvc")]
         public async Task IntrospectJsonContentFiles_WithExcludeConfigFilesFromBuildOutputSet()
         {
-            // Verifies that the fix for https://github.com/aspnet/AspNetCore/issues/14017 works.
+            // Verifies that the fix for https://github.com/dotnet/aspnetcore/issues/14017 works.
             var result = await DotnetMSBuild("_IntrospectContentItems", "/p:ExcludeConfigFilesFromBuildOutput=true");
 
             Assert.BuildPassed(result);
@@ -229,21 +229,21 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
         [InitializeTestProject("SimpleMvc")]
         public async Task IntrospectRazorTasksDllPath()
         {
-            // Regression test for https://github.com/aspnet/AspNetCore/issues/17308
+            // Regression test for https://github.com/dotnet/aspnetcore/issues/17308
             var solutionRoot = GetType().Assembly.GetCustomAttributes<AssemblyMetadataAttribute>()
                 .First(a => a.Key == "Testing.RepoRoot")
                 .Value;
 
             var tfm =
-#if NETCOREAPP3_1
-                "netcoreapp3.1";
+#if NETCOREAPP5_0
+                "netcoreapp5.0";
 #else
 #error Target framework needs to be updated.
 #endif
 
             var expected = Path.Combine(solutionRoot, "artifacts", "bin", "Microsoft.NET.Sdk.Razor", Configuration, "sdk-output", "tasks", tfm, "Microsoft.NET.Sdk.Razor.Tasks.dll");
 
-            // Verifies the fix for https://github.com/aspnet/AspNetCore/issues/17308
+            // Verifies the fix for https://github.com/dotnet/aspnetcore/issues/17308
             var result = await DotnetMSBuild("_IntrospectRazorTasks");
 
             Assert.BuildPassed(result);
@@ -262,7 +262,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             var tfm = "net46";
             var expected = Path.Combine(solutionRoot, "artifacts", "bin", "Microsoft.NET.Sdk.Razor", Configuration, "sdk-output", "tasks", tfm, "Microsoft.NET.Sdk.Razor.Tasks.dll");
 
-            // Verifies the fix for https://github.com/aspnet/AspNetCore/issues/17308
+            // Verifies the fix for https://github.com/dotnet/aspnetcore/issues/17308
             var result = await DotnetMSBuild("_IntrospectRazorTasks", msBuildProcessKind: MSBuildProcessKind.Desktop);
 
             Assert.BuildPassed(result);
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/InitializeTestProjectAttribute.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/InitializeTestProjectAttribute.cs
index ebf9ddb067..0134607143 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/InitializeTestProjectAttribute.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/InitializeTestProjectAttribute.cs
@@ -38,7 +38,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
 
             MSBuildIntegrationTestBase.Project = ProjectDirectory.Create(_originalProjectName, _testProjectName, _baseDirectory, _additionalProjects, _language);
 #if NETCOREAPP
-            MSBuildIntegrationTestBase.TargetFramework = "netcoreapp3.1";
+            MSBuildIntegrationTestBase.TargetFramework = "netcoreapp5.0";
 #else
 #error Target frameworks need to be updated
 #endif
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/MSBuildIntegrationTestBase.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/MSBuildIntegrationTestBase.cs
index ddc33fb6f0..2a38d92bbe 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/MSBuildIntegrationTestBase.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/MSBuildIntegrationTestBase.cs
@@ -95,7 +95,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
                 // Let the test app know it is running as part of a test.
                 "/p:RunningAsTest=true",
 
-                $"/p:MicrosoftNETCoreApp31PackageVersion={BuildVariables.MicrosoftNETCoreApp31PackageVersion}",
+                $"/p:MicrosoftNETCoreApp50PackageVersion={BuildVariables.MicrosoftNETCoreApp50PackageVersion}",
                 $"/p:MicrosoftNetCompilersToolsetPackageVersion={BuildVariables.MicrosoftNetCompilersToolsetPackageVersion}",
 
                 // Additional restore sources for projects that require built packages
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/PackIntegrationTest.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/PackIntegrationTest.cs
index e148aa2b24..56c1cefaba 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/PackIntegrationTest.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/PackIntegrationTest.cs
@@ -11,7 +11,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
 {
     public class PackIntegrationTest : MSBuildIntegrationTestBase, IClassFixture<BuildServerTestFixture>
     {
-        private static readonly string TFM = "netcoreapp3.1";
+        private static readonly string TFM = "netcoreapp5.0";
 
         public PackIntegrationTest(BuildServerTestFixture buildServer)
             : base(buildServer)
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/PublishIntegrationTest.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/PublishIntegrationTest.cs
index 037600112b..f17512a89d 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/PublishIntegrationTest.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/PublishIntegrationTest.cs
@@ -329,7 +329,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             Assert.FileCountEquals(result, 0, Path.Combine(PublishOutputPath, "Views"), "*.cshtml");
         }
 
-        [Fact]
+        [Fact(Skip = "https://github.com/dotnet/aspnetcore/issues/13303")]
         [InitializeTestProject("SimpleMvcFSharp", language: "F#")]
         public async Task Publish_SimpleMvcFSharp_NoopsWithoutFailing()
         {
@@ -434,7 +434,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             var result = await DotnetMSBuild("Publish", "/p:NoBuild=true");
 
             Assert.BuildFailed(result);
-            Assert.BuildError(result, "MSB3030"); // Could not copy the file "obj/Debug/netcoreapp3.1/SimpleMvc.dll because it couldn't be found.
+            Assert.BuildError(result, "MSB3030"); // Could not copy the file "obj/Debug/netcoreapp5.0/SimpleMvc.dll because it couldn't be found.
 
             Assert.FileDoesNotExist(result, PublishOutputPath, "SimpleMvc.dll");
             Assert.FileDoesNotExist(result, PublishOutputPath, "SimpleMvc.Views.dll");
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/StaticWebAssetsIntegrationTest.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/StaticWebAssetsIntegrationTest.cs
index 905d31f970..b87b87a662 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/StaticWebAssetsIntegrationTest.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/IntegrationTests/StaticWebAssetsIntegrationTest.cs
@@ -33,7 +33,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
 
         public ITestOutputHelper Output { get; private set; }
 
-        [Fact(Skip = "https://github.com/aspnet/AspNetCore/issues/17233")]
+        [Fact(Skip = "https://github.com/dotnet/aspnetcore/issues/17233")]
         [InitializeTestProject("AppWithPackageAndP2PReference",language: "C#", additionalProjects: new[] { "ClassLibrary", "ClassLibrary2" })]
         public async Task Build_GeneratesStaticWebAssetsManifest_Success_CreatesManifest()
         {
@@ -84,7 +84,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             Assert.FileDoesNotExist(result, PublishOutputPath, "AppWithPackageAndP2PReference.StaticWebAssets.xml");
         }
 
-        [ConditionalFact]
+        [ConditionalFact(Skip = "Flaky test: https://github.com/dotnet/aspnetcore/issues/18543")]
         [OSSkipCondition(OperatingSystems.Linux | OperatingSystems.MacOSX)]
         [InitializeTestProject("AppWithPackageAndP2PReferenceAndRID", additionalProjects: new[] { "ClassLibrary", "ClassLibrary2" })]
         public async Task Publish_CopiesStaticWebAssetsToDestinationFolder_PublishSingleFile()
@@ -109,7 +109,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             Assert.FileDoesNotExist(result, publishOutputPath, "AppWithPackageAndP2PReference.StaticWebAssets.xml");
         }
 
-        [Fact]
+        [Fact(Skip = "flaky test: https://github.com/dotnet/aspnetcore/issues/18707")]
         [InitializeTestProject("AppWithPackageAndP2PReference", additionalProjects: new[] { "ClassLibrary", "ClassLibrary2" })]
         public async Task Publish_WithBuildReferencesDisabled_CopiesStaticWebAssetsToDestinationFolder()
         {
@@ -130,7 +130,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             Assert.FileExists(publish, PublishOutputPath, Path.Combine("wwwroot", "_content", "PackageLibraryTransitiveDependency", "js", "pkg-transitive-dep.js"));
         }
 
-        [Fact]
+        [Fact(Skip = "Flaky test: https://github.com/dotnet/aspnetcore/issues/18561")]
         [InitializeTestProject("AppWithPackageAndP2PReference", additionalProjects: new[] { "ClassLibrary", "ClassLibrary2" })]
         public async Task Publish_NoBuild_CopiesStaticWebAssetsToDestinationFolder()
         {
@@ -188,7 +188,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
             Assert.FileDoesNotExist(result, IntermediateOutputPath, "staticwebassets", "AppWithPackageAndP2PReference.StaticWebAssets.xml");
         }
 
-        [Fact(Skip = "https://github.com/aspnet/AspNetCore/issues/17233")]
+        [Fact(Skip = "https://github.com/dotnet/aspnetcore/issues/17233")]
         [InitializeTestProject("AppWithPackageAndP2PReference",language: "C#", additionalProjects: new[] { "ClassLibrary", "ClassLibrary2" })]
         public async Task Rebuild_Success_RecreatesManifestAndCache()
         {
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/Microsoft.NET.Sdk.Razor.Test.csproj b/src/Razor/Microsoft.NET.Sdk.Razor/test/Microsoft.NET.Sdk.Razor.Test.csproj
index 1f3678c219..0bba7a6407 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/Microsoft.NET.Sdk.Razor.Test.csproj
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/Microsoft.NET.Sdk.Razor.Test.csproj
@@ -7,7 +7,7 @@
       This is also a partial workaround for https://github.com/Microsoft/msbuild/issues/2661 - this project
       has netcoreapp dependencies that need to be built first.
     -->
-    <TargetFramework>$(DefaultNetCoreTargetFramework)</TargetFramework>
+    <TargetFramework>netcoreapp5.0</TargetFramework>
     <PreserveCompilationContext>true</PreserveCompilationContext>
     <DefineConstants Condition="'$(PreserveWorkingDirectory)'=='true'">$(DefineConstants);PRESERVE_WORKING_DIRECTORY</DefineConstants>
     <!-- Copy references locally so that we can use them in the test. -->
@@ -101,7 +101,7 @@ namespace Microsoft.AspNetCore.Razor.Design.IntegrationTests
         static partial void InitializeVariables()
         {
             _msBuildPath = @"$(_DesktopMSBuildPath)";
-            _microsoftNETCoreApp31PackageVersion = "$(MicrosoftNETCoreApp31PackageVersion)";
+            _MicrosoftNETCoreApp50PackageVersion = "$(MicrosoftNETCoreApp50PackageVersion)";
             _microsoftNetCompilersToolsetPackageVersion = "$(MicrosoftNetCompilersToolsetPackageVersion)";
         }
     }
diff --git a/src/Razor/Microsoft.NET.Sdk.Razor/test/ReferenceResolverTest.cs b/src/Razor/Microsoft.NET.Sdk.Razor/test/ReferenceResolverTest.cs
index 05dd86b430..5fcc9d1220 100644
--- a/src/Razor/Microsoft.NET.Sdk.Razor/test/ReferenceResolverTest.cs
+++ b/src/Razor/Microsoft.NET.Sdk.Razor/test/ReferenceResolverTest.cs
@@ -142,7 +142,7 @@ namespace Microsoft.AspNetCore.Razor.Tasks
         [Fact]
         public void Resolve_Works_WhenAssemblyReferencesAreRecursive()
         {
-            // Test for https://github.com/aspnet/AspNetCore/issues/12693
+            // Test for https://github.com/dotnet/aspnetcore/issues/12693
             // Arrange
             var resolver = new TestReferencesToMvcResolver(new[]
             {
diff --git a/src/Razor/test/testassets/AppWithPackageAndP2PReferenceAndRID/AppWithPackageAndP2PReferenceAndRID.csproj b/src/Razor/test/testassets/AppWithPackageAndP2PReferenceAndRID/AppWithPackageAndP2PReferenceAndRID.csproj
index d657733943..c6d44d95f5 100644
--- a/src/Razor/test/testassets/AppWithPackageAndP2PReferenceAndRID/AppWithPackageAndP2PReferenceAndRID.csproj
+++ b/src/Razor/test/testassets/AppWithPackageAndP2PReferenceAndRID/AppWithPackageAndP2PReferenceAndRID.csproj
@@ -14,6 +14,12 @@
   <ItemGroup>
     <!-- Avoid referencing the AspNetCore framework since we want the ability to target work-in-progress shims -->
     <FrameworkReference Remove="Microsoft.AspNetCore.App" />
+
+    <!-- RID specific installs attempts to restore runtime packs which cause cyclical dependencies .-->
+    <KnownFrameworkReference Remove="Microsoft.AspNetCore.App" />
+    <KnownFrameworkReference Remove="Microsoft.WindowsDesktop.App" />
+    <KnownFrameworkReference Remove="Microsoft.WindowsDesktop.App.WPF" />
+    <KnownFrameworkReference Remove="Microsoft.WindowsDesktop.App.WindowsForms" />
   </ItemGroup>
 
   <PropertyGroup Condition="'$(RunningAsTest)' == ''">
diff --git a/src/Razor/test/testassets/Directory.Build.targets b/src/Razor/test/testassets/Directory.Build.targets
index c2b36add81..1c03be36fc 100644
--- a/src/Razor/test/testassets/Directory.Build.targets
+++ b/src/Razor/test/testassets/Directory.Build.targets
@@ -2,11 +2,7 @@
   <Import Project="RazorTest.Introspection.targets" />
 
   <PropertyGroup>
-    <!--
-      The runtime version is only useful to restore and compile test projects, and not used to run tests.
-      We'll keep it pinned to a version that has already been shipped.
-     -->
-    <RuntimeFrameworkVersion Condition=" '$(TargetFramework)' == '$(DefaultNetCoreTargetFramework)' ">$(MicrosoftNETCoreAppRefPackageVersion)</RuntimeFrameworkVersion>
+    <RuntimeFrameworkVersion Condition=" '$(TargetFramework)' == '$(DefaultNetCoreTargetFramework)' ">$(MicrosoftNETCoreApp50PackageVersion)</RuntimeFrameworkVersion>
     <!-- aspnet/BuildTools#662 Don't police what version of NetCoreApp we use -->
     <NETCoreAppMaximumVersion>99.9</NETCoreAppMaximumVersion>
   </PropertyGroup>
diff --git a/src/Razor/test/testassets/MvcWithComponents/Test.cs b/src/Razor/test/testassets/MvcWithComponents/Test.cs
new file mode 100644
index 0000000000..eaa1ddd367
--- /dev/null
+++ b/src/Razor/test/testassets/MvcWithComponents/Test.cs
@@ -0,0 +1,9 @@
+namespace MvcWithComponents
+{
+    public class Test
+    {
+        public static string Foo { get; set; }
+
+        public static string Bar { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/src/Razor/test/testassets/MvcWithComponents/Views/Home/#FileName.cshtml b/src/Razor/test/testassets/MvcWithComponents/Views/Home/#FileName.cshtml
new file mode 100644
index 0000000000..c227f7c471
--- /dev/null
+++ b/src/Razor/test/testassets/MvcWithComponents/Views/Home/#FileName.cshtml
@@ -0,0 +1 @@
+@page "/filename"
diff --git a/src/Razor/test/testassets/MvcWithComponents/Views/Shared/NavMenu.razor b/src/Razor/test/testassets/MvcWithComponents/Views/Shared/NavMenu.razor
index d6eede9b18..e036fead2b 100644
--- a/src/Razor/test/testassets/MvcWithComponents/Views/Shared/NavMenu.razor
+++ b/src/Razor/test/testassets/MvcWithComponents/Views/Shared/NavMenu.razor
@@ -1,2 +1,4 @@
+@Test.Foo @* Used in a test. Don't remove *@
+
 NavMenu content
 
diff --git a/src/Razor/test/testassets/SimpleMvc22/TagHelpers/EnvironementTagHelper.cs b/src/Razor/test/testassets/SimpleMvc22/TagHelpers/EnvironementTagHelper.cs
new file mode 100644
index 0000000000..cca753a803
--- /dev/null
+++ b/src/Razor/test/testassets/SimpleMvc22/TagHelpers/EnvironementTagHelper.cs
@@ -0,0 +1,17 @@
+using Microsoft.AspNetCore.Razor.TagHelpers;
+
+// Used for testing purposes to verify multiple TagHelpers applying to a single element.
+namespace SimpleMvc22.TagHelpers
+{
+    /// <summary>
+    /// I made it!
+    /// </summary>
+    [HtmlTargetElement("environment")]
+    public class EnvironmentTagHelper : TagHelper
+    {
+        /// <summary>
+        /// Exclude it!
+        /// </summary>
+        public string Exclude {get; set;}
+    }
+}
\ No newline at end of file