diff --git a/dotnet/src/webdriver/Interactions/InputDevice.cs b/dotnet/src/webdriver/Interactions/InputDevice.cs
index 6db6e30a7d8b7..f73c0578e2586 100644
--- a/dotnet/src/webdriver/Interactions/InputDevice.cs
+++ b/dotnet/src/webdriver/Interactions/InputDevice.cs
@@ -21,6 +21,8 @@
 using System.Collections.Generic;
 using System.Globalization;
 
+#nullable enable
+
 namespace OpenQA.Selenium.Interactions
 {
     /// <summary>
@@ -28,12 +30,11 @@ namespace OpenQA.Selenium.Interactions
     /// </summary>
     public abstract class InputDevice
     {
-        private string deviceName;
-
         /// <summary>
         /// Initializes a new instance of the <see cref="InputDevice"/> class.
         /// </summary>
         /// <param name="deviceName">The unique name of the input device represented by this class.</param>
+        /// <exception cref="ArgumentException">If <paramref name="deviceName"/> is <see langword="null"/> or <see cref="string.Empty"/>.</exception>
         protected InputDevice(string deviceName)
         {
             if (string.IsNullOrEmpty(deviceName))
@@ -41,16 +42,13 @@ protected InputDevice(string deviceName)
                 throw new ArgumentException("Device name must not be null or empty", nameof(deviceName));
             }
 
-            this.deviceName = deviceName;
+            this.DeviceName = deviceName;
         }
 
         /// <summary>
         /// Gets the unique name of this input device.
         /// </summary>
-        public string DeviceName
-        {
-            get { return this.deviceName; }
-        }
+        public string DeviceName { get; }
 
         /// <summary>
         /// Gets the kind of device for this input device.
@@ -90,7 +88,7 @@ public Interaction CreatePause(TimeSpan duration)
         /// <returns>A hash code for the current <see cref="InputDevice"/>.</returns>
         public override int GetHashCode()
         {
-            return this.deviceName.GetHashCode();
+            return this.DeviceName.GetHashCode();
         }
 
         /// <summary>
@@ -99,7 +97,7 @@ public override int GetHashCode()
         /// <returns>A string that represents the current <see cref="InputDevice"/>.</returns>
         public override string ToString()
         {
-            return string.Format(CultureInfo.InvariantCulture, "{0} input device [name: {1}]", this.DeviceKind, this.deviceName);
+            return string.Format(CultureInfo.InvariantCulture, "{0} input device [name: {1}]", this.DeviceKind, this.DeviceName);
         }
     }
 }
diff --git a/dotnet/src/webdriver/Interactions/KeyInputDevice.cs b/dotnet/src/webdriver/Interactions/KeyInputDevice.cs
index 4273a59b6c0c0..d04a05e3866b4 100644
--- a/dotnet/src/webdriver/Interactions/KeyInputDevice.cs
+++ b/dotnet/src/webdriver/Interactions/KeyInputDevice.cs
@@ -21,6 +21,8 @@
 using System.Collections.Generic;
 using System.Globalization;
 
+#nullable enable
+
 namespace OpenQA.Selenium.Interactions
 {
     /// <summary>
@@ -40,6 +42,7 @@ public KeyInputDevice()
         /// Initializes a new instance of the <see cref="KeyInputDevice"/> class, given the device's name.
         /// </summary>
         /// <param name="deviceName">The unique name of this input device.</param>
+        /// <exception cref="ArgumentException">If <paramref name="deviceName"/> is <see langword="null"/> or <see cref="string.Empty"/>.</exception>
         public KeyInputDevice(string deviceName)
             : base(deviceName)
         {
@@ -48,10 +51,7 @@ public KeyInputDevice(string deviceName)
         /// <summary>
         /// Gets the type of device for this input device.
         /// </summary>
-        public override InputDeviceKind DeviceKind
-        {
-            get { return InputDeviceKind.Key; }
-        }
+        public override InputDeviceKind DeviceKind => InputDeviceKind.Key;
 
         /// <summary>
         /// Converts this input device into an object suitable for serializing across the wire.
@@ -115,27 +115,23 @@ public override string ToString()
 
         private class TypingInteraction : Interaction
         {
-            private string type;
-            private string value;
+            private readonly string type;
 
             public TypingInteraction(InputDevice sourceDevice, string type, char codePoint)
                 : base(sourceDevice)
             {
                 this.type = type;
-                this.value = codePoint.ToString();
+                this.Value = codePoint.ToString();
             }
 
-            protected string Value
-            {
-                get { return this.value; }
-            }
+            protected string Value { get; }
 
             public override Dictionary<string, object> ToDictionary()
             {
                 Dictionary<string, object> toReturn = new Dictionary<string, object>();
 
                 toReturn["type"] = this.type;
-                toReturn["value"] = this.value;
+                toReturn["value"] = this.Value;
 
                 return toReturn;
             }
diff --git a/dotnet/src/webdriver/Interactions/PointerInputDevice.cs b/dotnet/src/webdriver/Interactions/PointerInputDevice.cs
index ef57abe4e49cb..ca92a7136b378 100644
--- a/dotnet/src/webdriver/Interactions/PointerInputDevice.cs
+++ b/dotnet/src/webdriver/Interactions/PointerInputDevice.cs
@@ -22,6 +22,8 @@
 using System.Collections.Generic;
 using System.Globalization;
 
+#nullable enable
+
 namespace OpenQA.Selenium.Interactions
 {
     /// <summary>
@@ -107,7 +109,7 @@ public enum MouseButton
     /// </summary>
     public class PointerInputDevice : InputDevice
     {
-        private PointerKind pointerKind;
+        private readonly PointerKind pointerKind;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="PointerInputDevice"/> class.
@@ -131,6 +133,7 @@ public PointerInputDevice(PointerKind pointerKind)
         /// </summary>
         /// <param name="pointerKind">The kind of pointer represented by this input device.</param>
         /// <param name="deviceName">The unique name for this input device.</param>
+        /// <exception cref="ArgumentException">If <paramref name="deviceName"/> is <see langword="null"/> or <see cref="string.Empty"/>.</exception>
         public PointerInputDevice(PointerKind pointerKind, string deviceName)
             : base(deviceName)
         {
@@ -140,10 +143,7 @@ public PointerInputDevice(PointerKind pointerKind, string deviceName)
         /// <summary>
         /// Gets the type of device for this input device.
         /// </summary>
-        public override InputDeviceKind DeviceKind
-        {
-            get { return InputDeviceKind.Pointer; }
-        }
+        public override InputDeviceKind DeviceKind => InputDeviceKind.Pointer;
 
         /// <summary>
         /// Returns a value for this input device that can be transmitted across the wire to a remote end.
@@ -219,6 +219,7 @@ public Interaction CreatePointerUp(MouseButton button, PointerEventProperties pr
         /// <param name="yOffset">The vertical offset from the origin of the move.</param>
         /// <param name="duration">The length of time the move gesture takes to complete.</param>
         /// <returns>The action representing the pointer move gesture.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="target"/> is <see langword="null"/>.</exception>
         public Interaction CreatePointerMove(IWebElement target, int xOffset, int yOffset, TimeSpan duration)
         {
             return CreatePointerMove(target, xOffset, yOffset, duration, new PointerEventProperties());
@@ -233,6 +234,7 @@ public Interaction CreatePointerMove(IWebElement target, int xOffset, int yOffse
         /// <param name="duration">The length of time the move gesture takes to complete.</param>
         /// <param name="properties">The specifications for the pointer event interaction</param>
         /// <returns>The action representing the pointer move gesture.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="target"/> is <see langword="null"/>.</exception>
         public Interaction CreatePointerMove(IWebElement target, int xOffset, int yOffset, TimeSpan duration, PointerEventProperties properties)
         {
             return new PointerMoveInteraction(this, target, CoordinateOrigin.Element, xOffset, yOffset, duration, properties);
@@ -265,7 +267,7 @@ public Interaction CreatePointerMove(CoordinateOrigin origin, int xOffset, int y
         /// <param name="properties">The object containing additional proprties for this pointer move operation.</param>
         /// <returns>The action representing the pointer move gesture.</returns>
         /// <exception cref="ArgumentException">Thrown when passing CoordinateOrigin.Element into origin.
-        /// Users should us the other CreatePointerMove overload to move to a specific element.</exception>
+        /// Users should use the other CreatePointerMove overload to move to a specific element.</exception>
         public Interaction CreatePointerMove(CoordinateOrigin origin, int xOffset, int yOffset, TimeSpan duration, PointerEventProperties properties)
         {
             if (origin == CoordinateOrigin.Element)
@@ -290,44 +292,24 @@ public Interaction CreatePointerCancel()
         /// </summary>
         public class PointerEventProperties
         {
-            private double? width;
-            private double? height;
-            private double? pressure;
-            private double? tangentialPressure;
-            private int? tiltX;
-            private int? tiltY;
-            private int? twist;
-            private double? altitudeAngle;
-            private double? azimuthAngle;
-
             /// <summary>
             /// Gets or sets the width (magnitude on x-axis) in pixels of the contact geometry of the pointer.
             /// </summary>
-            public double? Width
-            {
-                get { return this.width; }
-                set { this.width = value; }
-            }
+            public double? Width { get; set; }
 
             /// <summary>
             /// Gets or sets the height (magnitude on y-axis) in pixels of the contact geometry of the pointer.
             /// </summary>
-            public double? Height
-            {
-                get { return this.height; }
-                set { this.height = value; }
-            }
+            public double? Height { get; set; }
+
             /// <summary>
             /// Gets or sets the normalized pressure of the pointer input.
             /// </summary>
             /// <remarks>
             /// 0 and 1 represent the minimum and maximum pressure the hardware is capable of detecting, respectively.
             /// </remarks>
-            public double? Pressure
-            {
-                get { return this.pressure; }
-                set { this.pressure = value; }
-            }
+            public double? Pressure { get; set; }
+
             /// <summary>
             /// Gets or sets the normalized tangential pressure (also known as barrel pressure) of the pointer input.
             /// </summary>
@@ -335,11 +317,8 @@ public double? Pressure
             /// Valid values are between -1 and 1 with 0 being the neutral position of the control.
             /// Some hardware may only support positive values between 0 and 1.
             /// </remarks>
-            public double? TangentialPressure
-            {
-                get { return this.tangentialPressure; }
-                set { this.tangentialPressure = value; }
-            }
+            public double? TangentialPressure { get; set; }
+
             /// <summary>
             /// Gets or sets the plane angle in degrees between the Y-Z plane and the plane containing
             /// both the transducer (e.g. pen stylus) axis and the Y axis..
@@ -347,11 +326,8 @@ public double? TangentialPressure
             /// <remarks>
             /// Valid values are between -90 and 90. A positive value is to the right.
             /// </remarks>
-            public int? TiltX
-            {
-                get { return this.tiltX; }
-                set { this.tiltX = value; }
-            }
+            public int? TiltX { get; set; }
+
             /// <summary>
             /// Gets or sets the plane angle in degrees between the X-Z plane and the plane containing
             /// both the transducer (e.g. pen stylus) axis and the X axis..
@@ -359,22 +335,16 @@ public int? TiltX
             /// <remarks>
             /// Valid values are between -90 and 90. A positive value is toward the user.
             /// </remarks>
-            public int? TiltY
-            {
-                get { return this.tiltY; }
-                set { this.tiltY = value; }
-            }
+            public int? TiltY { get; set; }
+
             /// <summary>
             /// Gets or sets the clockwise rotation in degrees of a transducer (e.g. stylus) around its own major axis
             /// </summary>
             /// <remarks>
             /// Valid values are between 0 and 359.
             /// </remarks>
-            public int? Twist
-            {
-                get { return this.twist; }
-                set { this.twist = value; }
-            }
+            public int? Twist { get; set; }
+
             /// <summary>
             /// Gets or sets the altitude in radians of the transducer (e.g. pen/stylus)
             /// </summary>
@@ -382,11 +352,8 @@ public int? Twist
             /// Valid values are between 0 and π/2, where 0 is parallel to the surface (X-Y plane),
             /// and π/2 is perpendicular to the surface.
             /// </remarks>
-            public double? AltitudeAngle
-            {
-                get { return this.altitudeAngle; }
-                set { this.altitudeAngle = value; }
-            }
+            public double? AltitudeAngle { get; set; }
+
             /// <summary>
             /// Gets or sets the azimuth angle (in radians) of the transducer (e.g. pen/stylus)
             /// </summary>
@@ -395,11 +362,7 @@ public double? AltitudeAngle
             /// where 0 represents a transducer whose cap is pointing in the direction of increasing X values,
             /// and the values progressively increase when going clockwise.
             /// </remarks>
-            public double? AzimuthAngle
-            {
-                get { return this.azimuthAngle; }
-                set { this.azimuthAngle = value; }
-            }
+            public double? AzimuthAngle { get; set; }
 
             /// <summary>
             /// Serializes the properties of this input device as a dictionary.
@@ -414,44 +377,44 @@ public Dictionary<string, object> ToDictionary()
                     toReturn["width"] = this.Width.Value;
                 }
 
-                if (this.height.HasValue)
+                if (this.Height.HasValue)
                 {
-                    toReturn["height"] = this.height.Value;
+                    toReturn["height"] = this.Height.Value;
                 }
 
-                if (this.pressure.HasValue)
+                if (this.Pressure.HasValue)
                 {
-                    toReturn["pressure"] = this.pressure.Value;
+                    toReturn["pressure"] = this.Pressure.Value;
                 }
 
-                if (this.tangentialPressure.HasValue)
+                if (this.TangentialPressure.HasValue)
                 {
-                    toReturn["tangentialPressure"] = this.tangentialPressure.Value;
+                    toReturn["tangentialPressure"] = this.TangentialPressure.Value;
                 }
 
-                if (this.tiltX.HasValue)
+                if (this.TiltX.HasValue)
                 {
-                    toReturn["tiltX"] = this.tiltX.Value;
+                    toReturn["tiltX"] = this.TiltX.Value;
                 }
 
-                if (this.tiltY.HasValue)
+                if (this.TiltY.HasValue)
                 {
-                    toReturn["tiltY"] = this.tiltY.Value;
+                    toReturn["tiltY"] = this.TiltY.Value;
                 }
 
-                if (this.twist.HasValue)
+                if (this.Twist.HasValue)
                 {
-                    toReturn["twist"] = this.twist.Value;
+                    toReturn["twist"] = this.Twist.Value;
                 }
 
-                if (this.altitudeAngle.HasValue)
+                if (this.AltitudeAngle.HasValue)
                 {
-                    toReturn["altitudeAngle"] = this.altitudeAngle.Value;
+                    toReturn["altitudeAngle"] = this.AltitudeAngle.Value;
                 }
 
-                if (this.azimuthAngle.HasValue)
+                if (this.AzimuthAngle.HasValue)
                 {
-                    toReturn["azimuthAngle"] = this.azimuthAngle.Value;
+                    toReturn["azimuthAngle"] = this.AzimuthAngle.Value;
                 }
 
                 return toReturn;
@@ -460,8 +423,8 @@ public Dictionary<string, object> ToDictionary()
 
         private class PointerDownInteraction : Interaction
         {
-            private MouseButton button;
-            private PointerEventProperties eventProperties;
+            private readonly MouseButton button;
+            private readonly PointerEventProperties eventProperties;
 
             public PointerDownInteraction(InputDevice sourceDevice, MouseButton button, PointerEventProperties properties)
                 : base(sourceDevice)
@@ -473,7 +436,7 @@ public PointerDownInteraction(InputDevice sourceDevice, MouseButton button, Poin
             public override Dictionary<string, object> ToDictionary()
             {
                 Dictionary<string, object> toReturn;
-                if (eventProperties == null)
+                if (eventProperties is null)
                 {
                     toReturn = new Dictionary<string, object>();
                 }
@@ -495,8 +458,8 @@ public override string ToString()
 
         private class PointerUpInteraction : Interaction
         {
-            private MouseButton button;
-            private PointerEventProperties eventProperties;
+            private readonly MouseButton button;
+            private readonly PointerEventProperties eventProperties;
 
             public PointerUpInteraction(InputDevice sourceDevice, MouseButton button, PointerEventProperties properties)
                 : base(sourceDevice)
@@ -508,7 +471,7 @@ public PointerUpInteraction(InputDevice sourceDevice, MouseButton button, Pointe
             public override Dictionary<string, object> ToDictionary()
             {
                 Dictionary<string, object> toReturn;
-                if (eventProperties == null)
+                if (eventProperties is null)
                 {
                     toReturn = new Dictionary<string, object>();
                 }
@@ -551,14 +514,14 @@ public override string ToString()
 
         private class PointerMoveInteraction : Interaction
         {
-            private IWebElement target;
-            private int x = 0;
-            private int y = 0;
+            private readonly IWebElement? target;
+            private readonly int x = 0;
+            private readonly int y = 0;
             private TimeSpan duration = TimeSpan.MinValue;
-            private CoordinateOrigin origin = CoordinateOrigin.Pointer;
-            private PointerEventProperties eventProperties;
+            private readonly CoordinateOrigin origin = CoordinateOrigin.Pointer;
+            private readonly PointerEventProperties eventProperties;
 
-            public PointerMoveInteraction(InputDevice sourceDevice, IWebElement target, CoordinateOrigin origin, int x, int y, TimeSpan duration, PointerEventProperties properties)
+            public PointerMoveInteraction(InputDevice sourceDevice, IWebElement? target, CoordinateOrigin origin, int x, int y, TimeSpan duration, PointerEventProperties properties)
                 : base(sourceDevice)
             {
                 if (target != null)
@@ -622,7 +585,7 @@ public override string ToString()
                 string originDescription = this.origin.ToString();
                 if (this.origin == CoordinateOrigin.Element)
                 {
-                    originDescription = this.target.ToString();
+                    originDescription = this.target?.ToString() ?? "<null>";
                 }
 
                 return string.Format(CultureInfo.InvariantCulture, "Pointer move [origin: {0}, x offset: {1}, y offset: {2}, duration: {3}ms]", originDescription, this.x, this.y, this.duration.TotalMilliseconds);
@@ -630,10 +593,10 @@ public override string ToString()
 
             private Dictionary<string, object> ConvertElement()
             {
-                IWebDriverObjectReference elementReference = this.target as IWebDriverObjectReference;
+                IWebDriverObjectReference? elementReference = this.target as IWebDriverObjectReference;
                 if (elementReference == null)
                 {
-                    IWrapsElement elementWrapper = this.target as IWrapsElement;
+                    IWrapsElement? elementWrapper = this.target as IWrapsElement;
                     if (elementWrapper != null)
                     {
                         elementReference = elementWrapper.WrappedElement as IWebDriverObjectReference;
diff --git a/dotnet/src/webdriver/Interactions/WheelInputDevice.cs b/dotnet/src/webdriver/Interactions/WheelInputDevice.cs
index 2016d229a08c2..8d690ba4c7db6 100644
--- a/dotnet/src/webdriver/Interactions/WheelInputDevice.cs
+++ b/dotnet/src/webdriver/Interactions/WheelInputDevice.cs
@@ -21,6 +21,8 @@
 using System;
 using System.Collections.Generic;
 
+#nullable enable
+
 namespace OpenQA.Selenium.Interactions
 {
     /// <summary>
@@ -40,6 +42,7 @@ public WheelInputDevice()
         /// Initializes a new instance of the <see cref="WheelInputDevice"/> class, given the device's name.
         /// </summary>
         /// <param name="deviceName">The unique name of this input device.</param>
+        /// <exception cref="ArgumentException">If <paramref name="deviceName"/> is <see langword="null"/> or <see cref="string.Empty"/>.</exception>
         public WheelInputDevice(string deviceName)
             : base(deviceName)
         {
@@ -48,10 +51,7 @@ public WheelInputDevice(string deviceName)
         /// <summary>
         /// Gets the type of device for this input device.
         /// </summary>
-        public override InputDeviceKind DeviceKind
-        {
-            get { return InputDeviceKind.Wheel; }
-        }
+        public override InputDeviceKind DeviceKind => InputDeviceKind.Wheel;
 
         /// <summary>
         /// Returns a value for this input device that can be transmitted across the wire to a remote end.
@@ -89,8 +89,14 @@ public Interaction CreateWheelScroll(int deltaX, int deltaY, TimeSpan duration)
         /// <param name="deltaY">The distance along the Y axis to scroll using the wheel.</param>
         /// <param name="duration">The duration of the scroll action.</param>
         /// <returns>The <see cref="Interaction"/> representing the wheel scroll.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="target"/> is <see langword="null"/>.</exception>
         public Interaction CreateWheelScroll(IWebElement target, int xOffset, int yOffset, int deltaX, int deltaY, TimeSpan duration)
         {
+            if (target is null)
+            {
+                throw new ArgumentNullException(nameof(target));
+            }
+
             return new WheelScrollInteraction(this, target, CoordinateOrigin.Element, xOffset, yOffset, deltaX, deltaY, duration);
         }
 
@@ -114,60 +120,39 @@ public Interaction CreateWheelScroll(CoordinateOrigin origin, int xOffset, int y
         /// </summary>
         public class ScrollOrigin
         {
-            private IWebElement element;
-            private bool viewport;
-            private int xOffset = 0;
-            private int yOffset = 0;
-
             /// <summary>
             /// Gets or sets the element for the scroll origin.
             /// </summary>
-            public IWebElement Element
-            {
-                get { return this.element; }
-                set { this.element = value; }
-            }
+            public IWebElement? Element { get; set; }
 
             /// <summary>
             /// Gets or sets a value indicating whether the viewport should be used as the origin.
             /// </summary>
-            public bool Viewport
-            {
-                get { return this.viewport; }
-                set { this.viewport = value; }
-            }
+            public bool Viewport { get; set; }
 
             /// <summary>
             /// Gets or sets the horizontal offset of the scroll origin.
             /// </summary>
-            public int XOffset
-            {
-                get { return this.xOffset; }
-                set { this.xOffset = value; }
-            }
+            public int XOffset { get; set; } = 0;
 
             /// <summary>
             /// Gets or sets the vertical offset of the scroll origin.
             /// </summary>
-            public int YOffset
-            {
-                get { return this.yOffset; }
-                set { this.yOffset = value; }
-            }
+            public int YOffset { get; set; } = 0;
 
         }
 
         private class WheelScrollInteraction : Interaction
         {
-            private IWebElement target;
-            private int x = 0;
-            private int y = 0;
-            private int deltaX = 0;
-            private int deltaY = 0;
-            private TimeSpan duration = TimeSpan.MinValue;
-            private CoordinateOrigin origin = CoordinateOrigin.Viewport;
-
-            public WheelScrollInteraction(InputDevice sourceDevice, IWebElement target, CoordinateOrigin origin, int x, int y, int deltaX, int deltaY, TimeSpan duration)
+            private readonly IWebElement? target;
+            private readonly int x = 0;
+            private readonly int y = 0;
+            private readonly int deltaX = 0;
+            private readonly int deltaY = 0;
+            private readonly TimeSpan duration = TimeSpan.MinValue;
+            private readonly CoordinateOrigin origin = CoordinateOrigin.Viewport;
+
+            public WheelScrollInteraction(InputDevice sourceDevice, IWebElement? target, CoordinateOrigin origin, int x, int y, int deltaX, int deltaY, TimeSpan duration)
                 : base(sourceDevice)
             {
                 if (target != null)
@@ -224,10 +209,10 @@ public override Dictionary<string, object> ToDictionary()
 
             private Dictionary<string, object> ConvertElement()
             {
-                IWebDriverObjectReference elementReference = this.target as IWebDriverObjectReference;
+                IWebDriverObjectReference? elementReference = this.target as IWebDriverObjectReference;
                 if (elementReference == null)
                 {
-                    IWrapsElement elementWrapper = this.target as IWrapsElement;
+                    IWrapsElement? elementWrapper = this.target as IWrapsElement;
                     if (elementWrapper != null)
                     {
                         elementReference = elementWrapper.WrappedElement as IWebDriverObjectReference;