diff --git a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net472.approved.txt b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net472.approved.txt
index d3074429d1..9f4af14a9e 100644
--- a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net472.approved.txt
+++ b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net472.approved.txt
@@ -72,11 +72,11 @@ namespace ReactiveUI
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
-        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.IObservable<TParam> withParameter, string? toEvent = null)
+        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.IObservable<TParam?> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
-        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.Linq.Expressions.Expression<System.Func<TViewModel, TParam>> withParameter, string? toEvent = null)
+        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.Linq.Expressions.Expression<System.Func<TViewModel, TParam?>> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
@@ -84,11 +84,11 @@ namespace ReactiveUI
     public class CommandBinderImplementation : Splat.IEnableLogger
     {
         public CommandBinderImplementation() { }
-        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.Func<TParam> withParameter, string? toEvent = null)
+        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.IObservable<TParam?> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
-        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.IObservable<TParam> withParameter, string? toEvent = null)
+        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.Linq.Expressions.Expression<System.Func<TViewModel, TParam?>> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
@@ -431,6 +431,10 @@ namespace ReactiveUI
         public void Dispose() { }
         public static ReactiveUI.ObservableAsPropertyHelper<T> Default(T? initialValue = default, System.Reactive.Concurrency.IScheduler? scheduler = null) { }
     }
+    public static class ObservableFuncMixins
+    {
+        public static System.IObservable<TResult?> ToObservable<TSource, TResult>(this TSource? source, System.Linq.Expressions.Expression<System.Func<TSource, TResult?>> expression, bool beforeChange = false, bool skipInitial = false) { }
+    }
     public static class ObservableLoggingMixin
     {
         public static System.IObservable<T> Log<T, TObj>(this System.IObservable<T> @this, TObj logObject, string? message = null, System.Func<T, string>? stringifier = null)
diff --git a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net5.0.approved.txt b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net5.0.approved.txt
index 6ad256a9a5..f0f88b0dab 100644
--- a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net5.0.approved.txt
+++ b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.net5.0.approved.txt
@@ -74,11 +74,11 @@ namespace ReactiveUI
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
-        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.IObservable<TParam> withParameter, string? toEvent = null)
+        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.IObservable<TParam?> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
-        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.Linq.Expressions.Expression<System.Func<TViewModel, TParam>> withParameter, string? toEvent = null)
+        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.Linq.Expressions.Expression<System.Func<TViewModel, TParam?>> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
@@ -86,11 +86,11 @@ namespace ReactiveUI
     public class CommandBinderImplementation : Splat.IEnableLogger
     {
         public CommandBinderImplementation() { }
-        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.Func<TParam> withParameter, string? toEvent = null)
+        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.IObservable<TParam?> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
-        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.IObservable<TParam> withParameter, string? toEvent = null)
+        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.Linq.Expressions.Expression<System.Func<TViewModel, TParam?>> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
@@ -426,6 +426,10 @@ namespace ReactiveUI
         public void Dispose() { }
         public static ReactiveUI.ObservableAsPropertyHelper<T> Default(T? initialValue = default, System.Reactive.Concurrency.IScheduler? scheduler = null) { }
     }
+    public static class ObservableFuncMixins
+    {
+        public static System.IObservable<TResult?> ToObservable<TSource, TResult>(this TSource? source, System.Linq.Expressions.Expression<System.Func<TSource, TResult?>> expression, bool beforeChange = false, bool skipInitial = false) { }
+    }
     public static class ObservableLoggingMixin
     {
         public static System.IObservable<T> Log<T, TObj>(this System.IObservable<T> @this, TObj logObject, string? message = null, System.Func<T, string>? stringifier = null)
diff --git a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.netcoreapp3.1.approved.txt b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.netcoreapp3.1.approved.txt
index aa48602277..7a858719b5 100644
--- a/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.netcoreapp3.1.approved.txt
+++ b/src/ReactiveUI.Tests/API/ApiApprovalTests.ReactiveUI.netcoreapp3.1.approved.txt
@@ -72,11 +72,11 @@ namespace ReactiveUI
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
-        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.IObservable<TParam> withParameter, string? toEvent = null)
+        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.IObservable<TParam?> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
-        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.Linq.Expressions.Expression<System.Func<TViewModel, TParam>> withParameter, string? toEvent = null)
+        public static ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(this TView view, TViewModel? viewModel, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> propertyName, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlName, System.Linq.Expressions.Expression<System.Func<TViewModel, TParam?>> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
@@ -84,11 +84,11 @@ namespace ReactiveUI
     public class CommandBinderImplementation : Splat.IEnableLogger
     {
         public CommandBinderImplementation() { }
-        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.Func<TParam> withParameter, string? toEvent = null)
+        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.IObservable<TParam?> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
-        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.IObservable<TParam> withParameter, string? toEvent = null)
+        public ReactiveUI.IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(TViewModel? viewModel, TView view, System.Linq.Expressions.Expression<System.Func<TViewModel, TProp?>> vmProperty, System.Linq.Expressions.Expression<System.Func<TView, TControl>> controlProperty, System.Linq.Expressions.Expression<System.Func<TViewModel, TParam?>> withParameter, string? toEvent = null)
             where TView :  class, ReactiveUI.IViewFor<TViewModel>
             where TViewModel :  class
             where TProp : System.Windows.Input.ICommand { }
@@ -424,6 +424,10 @@ namespace ReactiveUI
         public void Dispose() { }
         public static ReactiveUI.ObservableAsPropertyHelper<T> Default(T? initialValue = default, System.Reactive.Concurrency.IScheduler? scheduler = null) { }
     }
+    public static class ObservableFuncMixins
+    {
+        public static System.IObservable<TResult?> ToObservable<TSource, TResult>(this TSource? source, System.Linq.Expressions.Expression<System.Func<TSource, TResult?>> expression, bool beforeChange = false, bool skipInitial = false) { }
+    }
     public static class ObservableLoggingMixin
     {
         public static System.IObservable<T> Log<T, TObj>(this System.IObservable<T> @this, TObj logObject, string? message = null, System.Func<T, string>? stringifier = null)
diff --git a/src/ReactiveUI.Tests/Locator/DefaultViewLocatorTests.cs b/src/ReactiveUI.Tests/Locator/DefaultViewLocatorTests.cs
index 7018c16568..0427b4a639 100644
--- a/src/ReactiveUI.Tests/Locator/DefaultViewLocatorTests.cs
+++ b/src/ReactiveUI.Tests/Locator/DefaultViewLocatorTests.cs
@@ -65,7 +65,6 @@ public void TheRuntimeTypeOfTheViewModelIsUsedToResolveTheView()
         /// Tests that the view model to view naming convention can be customized.
         /// </summary>
         [Fact]
-        [SuppressMessage("Globalization", "CA1307:Specify StringComparison", Justification = "Not in all platforms.")]
         public void ViewModelToViewNamingConventionCanBeCustomized()
         {
             var resolver = new ModernDependencyResolver();
@@ -382,7 +381,6 @@ public void CanResolveViewFromViewModelWithIRoutableViewModelType()
         /// Tests that make sure this instance [can override name resolution function].
         /// </summary>
         [Fact]
-        [SuppressMessage("Globalization", "CA1307:Specify StringComparison", Justification = "Not in all frameworks.")]
         public void CanOverrideNameResolutionFunc()
         {
             var resolver = new ModernDependencyResolver();
diff --git a/src/ReactiveUI.Tests/Locator/Mocks/IBarViewModel.cs b/src/ReactiveUI.Tests/Locator/Mocks/IBarViewModel.cs
index 7e24dd6b88..2496255819 100644
--- a/src/ReactiveUI.Tests/Locator/Mocks/IBarViewModel.cs
+++ b/src/ReactiveUI.Tests/Locator/Mocks/IBarViewModel.cs
@@ -10,7 +10,6 @@ namespace ReactiveUI.Tests
     /// <summary>
     /// A mock interface view model.
     /// </summary>
-    [SuppressMessage("Design", "CA1040: Avoid empty interfaces", Justification = "Deliberate empty interface.")]
     public interface IBarViewModel
     {
     }
diff --git a/src/ReactiveUI.Tests/Locator/Mocks/IFooViewModel.cs b/src/ReactiveUI.Tests/Locator/Mocks/IFooViewModel.cs
index 5372a0d00d..b248f76104 100644
--- a/src/ReactiveUI.Tests/Locator/Mocks/IFooViewModel.cs
+++ b/src/ReactiveUI.Tests/Locator/Mocks/IFooViewModel.cs
@@ -10,7 +10,6 @@ namespace ReactiveUI.Tests
     /// <summary>
     /// A interface view model.
     /// </summary>
-    [SuppressMessage("Design", "CA1040: Avoid empty interfaces", Justification = "Deliberate empty interface.")]
     public interface IFooViewModel
     {
     }
diff --git a/src/ReactiveUI.Tests/Locator/Mocks/IStrangeInterfaceNotFollowingConvention.cs b/src/ReactiveUI.Tests/Locator/Mocks/IStrangeInterfaceNotFollowingConvention.cs
index 9d4403273d..5a88cb0034 100644
--- a/src/ReactiveUI.Tests/Locator/Mocks/IStrangeInterfaceNotFollowingConvention.cs
+++ b/src/ReactiveUI.Tests/Locator/Mocks/IStrangeInterfaceNotFollowingConvention.cs
@@ -10,7 +10,6 @@ namespace ReactiveUI.Tests
     /// <summary>
     /// A strange interface.
     /// </summary>
-    [SuppressMessage("Design", "CA1040: Avoid empty interfaces", Justification = "Deliberate empty interface.")]
     public interface IStrangeInterfaceNotFollowingConvention
     {
     }
diff --git a/src/ReactiveUI.Tests/ObservableAsPropertyHelper/Mocks/OAPHIndexerTestFixture.cs b/src/ReactiveUI.Tests/ObservableAsPropertyHelper/Mocks/OAPHIndexerTestFixture.cs
index ce07f0e73d..7b4b126b74 100644
--- a/src/ReactiveUI.Tests/ObservableAsPropertyHelper/Mocks/OAPHIndexerTestFixture.cs
+++ b/src/ReactiveUI.Tests/ObservableAsPropertyHelper/Mocks/OAPHIndexerTestFixture.cs
@@ -4,6 +4,7 @@
 // See the LICENSE file in the project root for full license information.
 
 using System.Diagnostics.CodeAnalysis;
+using System.Reactive.Linq;
 
 namespace ReactiveUI.Tests
 {
@@ -17,11 +18,28 @@ internal class OAPHIndexerTestFixture : ReactiveObject
         /// <summary>
         /// Initializes a new instance of the <see cref="OAPHIndexerTestFixture"/> class.
         /// </summary>
-        public OAPHIndexerTestFixture()
+        public OAPHIndexerTestFixture(int test)
         {
-            var temp = this.WhenAnyValue(f => f.Text)
-                           .ToProperty(this, f => f["Whatever"])
-                           .Value;
+            switch (test)
+            {
+                case 0:
+                    var temp = this.WhenAnyValue(f => f.Text)
+                                               .ToProperty(this, f => f["Whatever"])
+                                               .Value;
+                    break;
+
+                case 1:
+                    var temp1 = this.WhenAnyValue(f => f.Text)
+                                               .ToProperty(new ReactiveObject(), f => f.ToString())
+                                               .Value;
+                    break;
+
+                case 2:
+                    var temp2 = Observable.Return("happy")
+                                                .ToProperty(this, string.Empty)
+                                                .Value;
+                    break;
+            }
         }
 
         /// <summary>
@@ -38,7 +56,8 @@ public string? Text
         /// </summary>
         /// <param name="propertyName">Name of the property.</param>
         /// <returns>The string.</returns>
-        [SuppressMessage("Performance", "CA1822:Mark members as static", Justification = "Used by test.")]
+#pragma warning disable RCS1163 // Unused parameter.
         public string? this[string propertyName] => string.Empty;
+#pragma warning restore RCS1163 // Unused parameter.
     }
 }
diff --git a/src/ReactiveUI.Tests/ObservableAsPropertyHelper/ObservableAsPropertyHelperTest.cs b/src/ReactiveUI.Tests/ObservableAsPropertyHelper/ObservableAsPropertyHelperTest.cs
index b000fbbc15..784988f9bf 100644
--- a/src/ReactiveUI.Tests/ObservableAsPropertyHelper/ObservableAsPropertyHelperTest.cs
+++ b/src/ReactiveUI.Tests/ObservableAsPropertyHelper/ObservableAsPropertyHelperTest.cs
@@ -489,7 +489,7 @@ public void ToProperty_NameOf_ValidValuesProduced(string[] testWords, string[] f
         public void ToProperty_GivenIndexer_NotifiesOnExpectedPropertyName() =>
             new TestScheduler().With(scheduler =>
             {
-                var fixture = new OAPHIndexerTestFixture();
+                var fixture = new OAPHIndexerTestFixture(0);
                 var propertiesChanged = new List<string>();
 
                 fixture.PropertyChanged += (_, args) =>
@@ -504,5 +504,42 @@ public void ToProperty_GivenIndexer_NotifiesOnExpectedPropertyName() =>
 
                 Assert.Equal(new[] { "Text", "Item[]" }, propertiesChanged);
             });
+
+        /// <summary>
+        /// Tests to make sure that the ToProperty with a indexer notifies the expected property name.
+        /// </summary>
+        [Fact]
+        public void ToProperty_GivenIndexer_NotifiesOnExpectedPropertyName1() =>
+            new TestScheduler().With(scheduler =>
+            {
+                Assert.Throws<NotSupportedException>(() =>
+                {
+                    var fixture = new OAPHIndexerTestFixture(1);
+                    var propertiesChanged = new List<string>();
+
+                    fixture.PropertyChanged += (_, args) =>
+                    {
+                        if (args.PropertyName != null)
+                        {
+                            propertiesChanged.Add(args.PropertyName);
+                        }
+                    };
+
+                    fixture.Text = "awesome";
+                });
+            });
+
+        /// <summary>
+        /// Tests to make sure that the ToProperty with a indexer notifies the expected property name.
+        /// </summary>
+        [Fact]
+        public void ToProperty_GivenIndexer_NotifiesOnExpectedPropertyName2() =>
+            new TestScheduler().With(scheduler =>
+            {
+                Assert.Throws<ArgumentException>(() =>
+                {
+                    var fixture = new OAPHIndexerTestFixture(2);
+                });
+            });
     }
 }
diff --git a/src/ReactiveUI.Tests/Platforms/windows-xaml/Utilities/DispatcherUtilities.cs b/src/ReactiveUI.Tests/Platforms/windows-xaml/Utilities/DispatcherUtilities.cs
index b24f439dab..2d42d0011e 100644
--- a/src/ReactiveUI.Tests/Platforms/windows-xaml/Utilities/DispatcherUtilities.cs
+++ b/src/ReactiveUI.Tests/Platforms/windows-xaml/Utilities/DispatcherUtilities.cs
@@ -38,7 +38,6 @@ public static void DoEvents()
         /// </summary>
         /// <param name="f">Unused frame object..</param>
         /// <returns>Unused return value.</returns>
-        [SuppressMessage("Design", "CA1801: Parameter never used", Justification = "Used on some platforms.")]
         public static object? ExitFrame(object f)
         {
 #if !NETFX_CORE
diff --git a/src/ReactiveUI.Tests/Platforms/winforms/DefaultPropertyBindingTests.cs b/src/ReactiveUI.Tests/Platforms/winforms/DefaultPropertyBindingTests.cs
index b84c4a3339..8aed8d1095 100644
--- a/src/ReactiveUI.Tests/Platforms/winforms/DefaultPropertyBindingTests.cs
+++ b/src/ReactiveUI.Tests/Platforms/winforms/DefaultPropertyBindingTests.cs
@@ -13,8 +13,6 @@
 using ReactiveUI.Winforms;
 using Xunit;
 
-#pragma warning disable SA1403 // FileMayOnlyContainASingleNamespace
-
 namespace ReactiveUI.Tests.Winforms
 {
     /// <summary>
diff --git a/src/ReactiveUI.Tests/Platforms/wpf/WpfCommandBindingImplementationTests.cs b/src/ReactiveUI.Tests/Platforms/wpf/WpfCommandBindingImplementationTests.cs
index 62afd381b3..a97c654730 100644
--- a/src/ReactiveUI.Tests/Platforms/wpf/WpfCommandBindingImplementationTests.cs
+++ b/src/ReactiveUI.Tests/Platforms/wpf/WpfCommandBindingImplementationTests.cs
@@ -1,4 +1,4 @@
-// Copyright (c) 2021 .NET Foundation and Contributors. All rights reserved.
+// Copyright (c) 2021 .NET Foundation and Contributors. All rights reserved.
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
@@ -189,77 +189,69 @@ public void CommandBindViewModelToViewWithObservable()
             var view = new CommandBindingView { ViewModel = vm };
 
             // Create a paramenter feed
-            var invokeCount = 0;
-            vm.Command2.Subscribe(_ => invokeCount++);
+            vm.Command2.Subscribe(_ => vm.Value++);
             view.BindCommand(vm, x => x.Command2, x => x.Command2, "MouseUp");
 
             // Bind the command and the IObservable parameter.
-            var fixture = new CommandBinderImplementation().BindCommand(vm, view, vm => vm.Command1, v => v.Command3, vm.Command2.Select(_ => invokeCount), "MouseUp");
-            Assert.Equal(0, invokeCount);
+            var fixture = new CommandBinderImplementation().BindCommand(vm, view, vm => vm.Command1, v => v.Command3, vm.WhenAnyValue(vm => vm.Value), "MouseUp");
+            Assert.Equal(0, vm.Value);
 
             // Confirm that the values update as expected.
             var parameter = 0;
             vm.Command1.Subscribe(i => parameter = i);
             view.Command2.RaiseEvent(new MouseButtonEventArgs(Mouse.PrimaryDevice, 0, MouseButton.Left) { RoutedEvent = UIElement.MouseUpEvent });
-            Assert.Equal(1, invokeCount);
+            Assert.Equal(1, vm.Value);
             Assert.Equal(0, parameter);
 
             view.Command3.RaiseEvent(new MouseButtonEventArgs(Mouse.PrimaryDevice, 0, MouseButton.Left) { RoutedEvent = UIElement.MouseUpEvent });
             Assert.Equal(1, parameter);
 
             view.Command2.RaiseEvent(new MouseButtonEventArgs(Mouse.PrimaryDevice, 0, MouseButton.Left) { RoutedEvent = UIElement.MouseUpEvent });
-            Assert.Equal(2, invokeCount);
+            Assert.Equal(2, vm.Value);
             Assert.Equal(1, parameter);
 
             view.Command3.RaiseEvent(new MouseButtonEventArgs(Mouse.PrimaryDevice, 0, MouseButton.Left) { RoutedEvent = UIElement.MouseUpEvent });
             Assert.Equal(2, parameter);
-            Assert.Equal(2, invokeCount);
+            Assert.Equal(2, vm.Value);
         }
 
         /// <summary>
         /// Commands the bind view model to view with function.
         /// </summary>
-        [Fact(Skip = "Need to resolve Func<T> to IObservable<T> bug exists if using this overload. Implimentation uses a ReactiveCommand for Parameter but does not reflect the required types")]
+        [Fact]
         public void CommandBindViewModelToViewWithFunc()
         {
-            ////////////////////////////////////////////
-            //// TEST FAILING NEED TO FIND RESOLVE /////
-            ////////////////////////////////////////////
-
             var vm = new CommandBindingViewModel();
             var view = new CommandBindingView { ViewModel = vm };
 
             // Create a paramenter feed
-            var invokeCount = 0;
-            var func = new Func<int>(() => invokeCount);
             vm.Command2.Subscribe(_ =>
             {
-                invokeCount++;
-                func();
+                vm.Value++;
             });
             view.BindCommand(vm, x => x.Command2, x => x.Command2, "MouseUp");
 
             // Bind the command and the Func<T> parameter.
-            var fixture = new CommandBinderImplementation().BindCommand(vm, view, vm => vm.Command1, v => v.Command3, func, "MouseUp");
-            Assert.Equal(0, invokeCount);
+            var fixture = new CommandBinderImplementation().BindCommand(vm, view, vm => vm.Command1, v => v.Command3, vm => vm.Value, "MouseUp");
+            Assert.Equal(0, vm.Value);
 
             // Confirm that the values update as expected.
             var parameter = 0;
             vm.Command1.Subscribe(i => parameter = i);
             view.Command2.RaiseEvent(new MouseButtonEventArgs(Mouse.PrimaryDevice, 0, MouseButton.Left) { RoutedEvent = UIElement.MouseUpEvent });
-            Assert.Equal(1, invokeCount);
+            Assert.Equal(1, vm.Value);
             Assert.Equal(0, parameter);
 
             view.Command3.RaiseEvent(new MouseButtonEventArgs(Mouse.PrimaryDevice, 0, MouseButton.Left) { RoutedEvent = UIElement.MouseUpEvent });
             Assert.Equal(1, parameter);
 
             view.Command2.RaiseEvent(new MouseButtonEventArgs(Mouse.PrimaryDevice, 0, MouseButton.Left) { RoutedEvent = UIElement.MouseUpEvent });
-            Assert.Equal(2, invokeCount);
+            Assert.Equal(2, vm.Value);
             Assert.Equal(1, parameter);
 
             view.Command3.RaiseEvent(new MouseButtonEventArgs(Mouse.PrimaryDevice, 0, MouseButton.Left) { RoutedEvent = UIElement.MouseUpEvent });
             Assert.Equal(2, parameter);
-            Assert.Equal(2, invokeCount);
+            Assert.Equal(2, vm.Value);
         }
 
         [Fact]
diff --git a/src/ReactiveUI.Tests/Resolvers/DependencyResolverTests.cs b/src/ReactiveUI.Tests/Resolvers/DependencyResolverTests.cs
index f73771caa1..3c5bae8953 100644
--- a/src/ReactiveUI.Tests/Resolvers/DependencyResolverTests.cs
+++ b/src/ReactiveUI.Tests/Resolvers/DependencyResolverTests.cs
@@ -97,7 +97,6 @@ public void AllDefaultServicesShouldBeRegisteredPerRegistrationNamespace(IEnumer
 
         [Theory]
         [MemberData(nameof(NamespacesToRegister))]
-        [SuppressMessage("Globalization", "CA1307:Specify StringComparison", Justification = "Not in NET472")]
         public void RegisteredNamespacesShouldBeRegistered(IEnumerable<RegistrationNamespace> namespacesToRegister)
         {
             var resolver = GenerateResolver();
diff --git a/src/ReactiveUI.Tests/Resolvers/PocoObservableForPropertyTests.cs b/src/ReactiveUI.Tests/Resolvers/PocoObservableForPropertyTests.cs
index 312f6cc095..50bde9adfb 100644
--- a/src/ReactiveUI.Tests/Resolvers/PocoObservableForPropertyTests.cs
+++ b/src/ReactiveUI.Tests/Resolvers/PocoObservableForPropertyTests.cs
@@ -78,7 +78,6 @@ public void NotificationPocoErrorOnBind()
         }
 
         [Fact]
-        [SuppressMessage("Globalization", "CA1307:Specify StringComparison", Justification = "Not in NET472")]
         public void NotificationPocoSuppressErrorOnBind()
         {
             using (var testLoggerRegistration = new TestLoggerRegistration())
diff --git a/src/ReactiveUI.Tests/Routing/Mocks/TestScreen.cs b/src/ReactiveUI.Tests/Routing/Mocks/TestScreen.cs
index 197fbb7755..8038ab5cbb 100644
--- a/src/ReactiveUI.Tests/Routing/Mocks/TestScreen.cs
+++ b/src/ReactiveUI.Tests/Routing/Mocks/TestScreen.cs
@@ -19,9 +19,7 @@ public class TestScreen : ReactiveObject, IScreen
         public RoutingState? Router
         {
 #pragma warning disable CS8766 // Nullability of reference types in return type doesn't match implicitly implemented member (possibly because of nullability attributes).
-#pragma warning disable CS8613 // Nullability of reference types in return type doesn't match implicitly implemented member.
             get => _router;
-#pragma warning restore CS8613 // Nullability of reference types in return type doesn't match implicitly implemented member.
 #pragma warning restore CS8766 // Nullability of reference types in return type doesn't match implicitly implemented member (possibly because of nullability attributes).
             set => this.RaiseAndSetIfChanged(ref _router, value);
         }
diff --git a/src/ReactiveUI.Tests/WaitForDispatcherSchedulerTests.cs b/src/ReactiveUI.Tests/WaitForDispatcherSchedulerTests.cs
index 05940e9109..56eefe9a39 100644
--- a/src/ReactiveUI.Tests/WaitForDispatcherSchedulerTests.cs
+++ b/src/ReactiveUI.Tests/WaitForDispatcherSchedulerTests.cs
@@ -42,10 +42,7 @@ public void CallSchedulerFactoryOnCreation()
         public void FactoryThrowsArgumentNullException_FallsBackToCurrentThread()
         {
             IScheduler? schedulerExecutedOn = null;
-#pragma warning disable CA2208 // Instantiate argument exceptions correctly
             var schedulerFactory = new Func<IScheduler>(() => throw new ArgumentNullException());
-#pragma warning restore CA2208 // Instantiate argument exceptions correctly
-
             var sut = new WaitForDispatcherScheduler(schedulerFactory);
             sut.Schedule<object>(
                                  null!,
diff --git a/src/ReactiveUI.Tests/WhenAny/TestWhenAnyObsViewModel.cs b/src/ReactiveUI.Tests/WhenAny/TestWhenAnyObsViewModel.cs
index 2e98760471..ad94c360c0 100644
--- a/src/ReactiveUI.Tests/WhenAny/TestWhenAnyObsViewModel.cs
+++ b/src/ReactiveUI.Tests/WhenAny/TestWhenAnyObsViewModel.cs
@@ -36,7 +36,6 @@ public IObservable<IChangeSet<int>>? Changes
 
         public ReactiveCommand<string, string> Command3 { get; set; }
 
-        [System.Diagnostics.CodeAnalysis.SuppressMessage("Usage", "CA2227:Collection properties should be read only", Justification = "Test usage")]
         public ObservableCollectionExtended<int>? MyListOfInts
         {
             get => _myListOfInts;
diff --git a/src/ReactiveUI/Bindings/Command/CommandBinder.cs b/src/ReactiveUI/Bindings/Command/CommandBinder.cs
index e7e3e9420b..cc8a00cce9 100644
--- a/src/ReactiveUI/Bindings/Command/CommandBinder.cs
+++ b/src/ReactiveUI/Bindings/Command/CommandBinder.cs
@@ -51,7 +51,7 @@ public static IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TPro
                 TViewModel? viewModel,
                 Expression<Func<TViewModel, TProp?>> propertyName,
                 Expression<Func<TView, TControl>> controlName,
-                IObservable<TParam> withParameter,
+                IObservable<TParam?> withParameter,
                 string? toEvent = null)
             where TView : class, IViewFor<TViewModel>
             where TViewModel : class
@@ -113,7 +113,7 @@ public static IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TPro
                 TViewModel? viewModel,
                 Expression<Func<TViewModel, TProp?>> propertyName,
                 Expression<Func<TView, TControl>> controlName,
-                Expression<Func<TViewModel, TParam>> withParameter,
+                Expression<Func<TViewModel, TParam?>> withParameter,
                 string? toEvent = null)
             where TView : class, IViewFor<TViewModel>
             where TViewModel : class
diff --git a/src/ReactiveUI/Bindings/Command/CommandBinderImplementation.cs b/src/ReactiveUI/Bindings/Command/CommandBinderImplementation.cs
index 1f77a0455f..e1fa62a2bd 100644
--- a/src/ReactiveUI/Bindings/Command/CommandBinderImplementation.cs
+++ b/src/ReactiveUI/Bindings/Command/CommandBinderImplementation.cs
@@ -38,14 +38,19 @@ public class CommandBinderImplementation : ICommandBinderImplementation
         /// instead of the default.
         /// NOTE: If this parameter is used inside WhenActivated, it's
         /// important to dispose the binding when the view is deactivated.</param>
-        /// <returns>A class representing the binding. Dispose it to disconnect
-        /// the binding.</returns>
+        /// <returns>
+        /// A class representing the binding. Dispose it to disconnect
+        /// the binding.
+        /// </returns>
+        /// <exception cref="ArgumentNullException">nameof(vmProperty)
+        /// or
+        /// nameof(vmProperty).</exception>
         public IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, TParam>(
                 TViewModel? viewModel,
                 TView view,
                 Expression<Func<TViewModel, TProp?>> vmProperty,
                 Expression<Func<TView, TControl>> controlProperty,
-                Func<TParam> withParameter,
+                Expression<Func<TViewModel, TParam?>> withParameter,
                 string? toEvent = null)
             where TView : class, IViewFor<TViewModel>
             where TViewModel : class
@@ -65,10 +70,7 @@ public IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TCon
             var controlExpression = Reflection.Rewrite(controlProperty.Body);
             var source = Reflection.ViewModelWhenAnyValue(viewModel, view, vmExpression).Cast<TProp>();
 
-            var bindingDisposable = BindCommandInternal(source, view, controlExpression, Observable.Defer(() => Observable.Return(withParameter())), toEvent, cmd =>
-            cmd is IReactiveCommand rc
-                    ? ReactiveCommand.Create(() => ((ICommand)rc).Execute(null), rc.CanExecute)
-                    : new RelayCommand(cmd.CanExecute, _ => cmd.Execute(withParameter())));
+            var bindingDisposable = BindCommandInternal(source, view, controlExpression, viewModel.ToObservable(withParameter), toEvent);
 
             return new ReactiveBinding<TView, TProp>(
                 view,
@@ -105,7 +107,7 @@ public IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TCon
                 TView view,
                 Expression<Func<TViewModel, TProp?>> vmProperty,
                 Expression<Func<TView, TControl>> controlProperty,
-                IObservable<TParam> withParameter,
+                IObservable<TParam?> withParameter,
                 string? toEvent = null)
             where TView : class, IViewFor<TViewModel>
             where TViewModel : class
@@ -141,8 +143,7 @@ private static IDisposable BindCommandInternal<TView, TProp, TParam>(
                 TView view,
                 Expression controlExpression,
                 IObservable<TParam> withParameter,
-                string? toEvent,
-                Func<ICommand, ICommand>? commandFixuper = null)
+                string? toEvent)
             where TView : class, IViewFor
             where TProp : ICommand
         {
@@ -167,11 +168,9 @@ private static IDisposable BindCommandInternal<TView, TProp, TParam>(
                         return;
                     }
 
-                    var cmd = commandFixuper is not null ? commandFixuper(x.val) : x.val;
-
                     disposable = !string.IsNullOrEmpty(toEvent) ?
-                               CreatesCommandBinding.BindCommandToObject(cmd, x.host, withParameter.Select(y => (object)y!), toEvent) :
-                               CreatesCommandBinding.BindCommandToObject(cmd, x.host, withParameter.Select(y => (object)y!));
+                               CreatesCommandBinding.BindCommandToObject(x.val, x.host, withParameter.Select(y => (object)y!), toEvent) :
+                               CreatesCommandBinding.BindCommandToObject(x.val, x.host, withParameter.Select(y => (object)y!));
                 });
 
             return Disposable.Create(() =>
diff --git a/src/ReactiveUI/Bindings/Command/ICommandBinderImplementation.cs b/src/ReactiveUI/Bindings/Command/ICommandBinderImplementation.cs
index e7f4e8e5be..dcad2f84a7 100644
--- a/src/ReactiveUI/Bindings/Command/ICommandBinderImplementation.cs
+++ b/src/ReactiveUI/Bindings/Command/ICommandBinderImplementation.cs
@@ -35,7 +35,7 @@ IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, T
                 TView view,
                 Expression<Func<TViewModel, TProp?>> vmProperty,
                 Expression<Func<TView, TControl>> controlProperty,
-                Func<TParam> withParameter,
+                Expression<Func<TViewModel, TParam?>> withParameter,
                 string? toEvent = null)
             where TView : class, IViewFor<TViewModel>
             where TViewModel : class
@@ -61,7 +61,7 @@ IReactiveBinding<TView, TProp> BindCommand<TView, TViewModel, TProp, TControl, T
                 TView view,
                 Expression<Func<TViewModel, TProp?>> vmProperty,
                 Expression<Func<TView, TControl>> controlProperty,
-                IObservable<TParam> withParameter,
+                IObservable<TParam?> withParameter,
                 string? toEvent = null)
             where TView : class, IViewFor<TViewModel>
             where TViewModel : class
diff --git a/src/ReactiveUI/ObservableFuncMixins.cs b/src/ReactiveUI/ObservableFuncMixins.cs
new file mode 100644
index 0000000000..c8420bb9d7
--- /dev/null
+++ b/src/ReactiveUI/ObservableFuncMixins.cs
@@ -0,0 +1,41 @@
+// Copyright (c) 2021 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using System;
+using System.Linq.Expressions;
+using System.Reactive.Linq;
+
+namespace ReactiveUI
+{
+    /// <summary>
+    /// Observable Func Mixins.
+    /// </summary>
+    public static class ObservableFuncMixins
+    {
+        /// <summary>
+        /// Converts to observable.
+        /// </summary>
+        /// <typeparam name="TSource">The type of the view model.</typeparam>
+        /// <typeparam name="TResult">The type of the result.</typeparam>
+        /// <param name="source">The view model.</param>
+        /// <param name="expression">The expression.</param>
+        /// <param name="beforeChange">if set to <c>true</c> [before change].</param>
+        /// <param name="skipInitial">if set to <c>true</c> [skip initial].</param>
+        /// <returns>
+        /// An observable Result.
+        /// </returns>
+        public static IObservable<TResult?> ToObservable<TSource, TResult>(
+            this TSource? source,
+            Expression<Func<TSource, TResult?>> expression,
+            bool beforeChange = false,
+            bool skipInitial = false)
+        {
+            var sParam = Reflection.Rewrite(expression.Body);
+            return source.SubscribeToExpressionChain<TSource, TResult?>(sParam, beforeChange, skipInitial, RxApp.SuppressViewCommandBindingMessage)
+                .Select(x => x.GetValue())
+                .Retry();
+        }
+    }
+}