diff --git a/src/Avalonia.Controls/SplitButton/SplitButton.cs b/src/Avalonia.Controls/SplitButton/SplitButton.cs
deleted file mode 100644
index 5c75a8d09d..0000000000
--- a/src/Avalonia.Controls/SplitButton/SplitButton.cs
+++ /dev/null
@@ -1,735 +0,0 @@
-using System;
-using System.Reactive.Disposables;
-using System.Windows.Input;
-using Avalonia.Controls.Metadata;
-using Avalonia.Controls.Primitives;
-using Avalonia.Input;
-using Avalonia.Interactivity;
-using Avalonia.LogicalTree;
-
-namespace Avalonia.Controls
-{
-    /// <summary>
-    /// A button with primary and secondary parts that can each be pressed separately.
-    /// The primary part behaves like a <see cref="Button"/> and the secondary part opens a flyout.
-    /// </summary>
-    [PseudoClasses(
-        pcDisabled,
-        pcSecondaryButtonRight,
-        pcSecondaryButtonSpan,
-        pcCheckedFlyoutOpen,
-        pcFlyoutOpen,
-        pcCheckedTouchPressed,
-        pcChecked,
-        pcCheckedPrimaryPressed,
-        pcCheckedPrimaryPointerOver,
-        pcCheckedSecondaryPressed,
-        pcCheckedSecondaryPointerOver,
-        pcTouchPressed,
-        pcPrimaryPressed,
-        pcPrimaryPointerOver,
-        pcSecondaryPressed,
-        pcSecondaryPointerOver)]
-    public class SplitButton : ContentControl, ICommandSource
-    {
-        private const string pcDisabled = ":disabled";
-
-        private const string pcSecondaryButtonRight = ":secondary-button-right";
-        private const string pcSecondaryButtonSpan  = ":secondary-button-span";
-
-        private const string pcCheckedFlyoutOpen = ":checked-flyout-open";
-        private const string pcFlyoutOpen        = ":flyout-open";
-
-        private const string pcCheckedTouchPressed         = ":checked-touch-pressed";
-        private const string pcChecked                     = ":checked";
-        private const string pcCheckedPrimaryPressed       = ":checked-primary-pressed";
-        private const string pcCheckedPrimaryPointerOver   = ":checked-primary-pointerover";
-        private const string pcCheckedSecondaryPressed     = ":checked-secondary-pressed";
-        private const string pcCheckedSecondaryPointerOver = ":checked-secondary-pointerover";
-
-        private const string pcTouchPressed         = ":touch-pressed";
-        private const string pcPrimaryPressed       = ":primary-pressed";
-        private const string pcPrimaryPointerOver   = ":primary-pointerover";
-        private const string pcSecondaryPressed     = ":secondary-pressed";
-        private const string pcSecondaryPointerOver = ":secondary-pointerover";
-
-        /// <summary>
-        /// Raised when the user presses the primary part of the <see cref="SplitButton"/>.
-        /// </summary>
-        public event EventHandler<RoutedEventArgs> Click
-        {
-            add => AddHandler(ClickEvent, value);
-            remove => RemoveHandler(ClickEvent, value);
-        }
-
-        /// <summary>
-        /// Defines the <see cref="Click"/> event.
-        /// </summary>
-        public static readonly RoutedEvent<RoutedEventArgs> ClickEvent =
-            RoutedEvent.Register<SplitButton, RoutedEventArgs>(
-                nameof(Click),
-                RoutingStrategies.Bubble);
-
-        /// <summary>
-        /// Defines the <see cref="Command"/> property.
-        /// </summary>
-        public static readonly DirectProperty<SplitButton, ICommand> CommandProperty =
-            AvaloniaProperty.RegisterDirect<SplitButton, ICommand>(
-                nameof(Command),
-                splitButton => splitButton.Command,
-                (splitButton, command) => splitButton.Command = command,
-                enableDataValidation: true);
-
-        /// <summary>
-        /// Defines the <see cref="CommandParameter"/> property.
-        /// </summary>
-        public static readonly StyledProperty<object> CommandParameterProperty =
-            AvaloniaProperty.Register<SplitButton, object>(
-                nameof(CommandParameter));
-
-        /// <summary>
-        /// Defines the <see cref="Flyout"/> property
-        /// </summary>
-        public static readonly StyledProperty<FlyoutBase> FlyoutProperty =
-            AvaloniaProperty.Register<SplitButton, FlyoutBase>(
-                nameof(Flyout));
-
-        private ICommand _Command;
-
-        private Button _primaryButton   = null;
-        private Button _secondaryButton = null;
-
-        private bool        _commandCanExecute       = true;
-        protected bool      _hasLoaded               = false;
-        private bool        _isAttachedToLogicalTree = false;
-        private bool        _isFlyoutOpen            = false;
-        private bool        _isKeyDown               = false;
-        private PointerType _lastPointerType         = PointerType.Mouse;
-
-        private CompositeDisposable _buttonPropertyChangedDisposable;
-        private IDisposable         _flyoutPropertyChangedDisposable;
-
-        ////////////////////////////////////////////////////////////////////////
-        // Constructor / Destructors
-        ////////////////////////////////////////////////////////////////////////
-
-        /// <summary>
-        /// Initializes a new instance of the <see cref="SplitButton"/> class.
-        /// </summary>
-        public SplitButton()
-        {
-        }
-
-        ////////////////////////////////////////////////////////////////////////
-        // Properties
-        ////////////////////////////////////////////////////////////////////////
-
-        /// <summary>
-        /// Gets or sets the <see cref="ICommand"/> invoked when the primary part is pressed.
-        /// </summary>
-        public ICommand Command
-        {
-            get => _Command;
-            set => SetAndRaise(CommandProperty, ref _Command, value);
-        }
-
-        /// <summary>
-        /// Gets or sets a parameter to be passed to the <see cref="Command"/>.
-        /// </summary>
-        public object CommandParameter
-        {
-            get => GetValue(CommandParameterProperty);
-            set => SetValue(CommandParameterProperty, value);
-        }
-
-        /// <summary>
-        /// Gets or sets the <see cref="FlyoutBase"/> that is shown when the secondary part is pressed.
-        /// </summary>
-        public FlyoutBase Flyout
-        {
-            get => GetValue(FlyoutProperty);
-            set => SetValue(FlyoutProperty, value);
-        }
-
-        /// <summary>
-        /// Gets a value indicating whether the button is currently checked.
-        /// </summary>
-        /// <remarks>
-        /// This property exists only for the derived <see cref="ToggleSplitButton"/> and is
-        /// unused (set to false) within <see cref="SplitButton"/>. Doing this allows the
-        /// two controls to share a default style.
-        /// </remarks>
-        internal virtual bool InternalIsChecked => false;
-
-        /// <inheritdoc/>
-        protected override bool IsEnabledCore => base.IsEnabledCore && _commandCanExecute;
-
-        ////////////////////////////////////////////////////////////////////////
-        // Methods
-        ////////////////////////////////////////////////////////////////////////
-
-        /// <inheritdoc/>
-        public void CanExecuteChanged(object sender, EventArgs e)
-        {
-            var canExecute = Command == null || Command.CanExecute(CommandParameter);
-
-            if (canExecute != _commandCanExecute)
-            {
-                _commandCanExecute = canExecute;
-                UpdateIsEffectivelyEnabled();
-            }
-        }
-
-        /// <summary>
-        /// Updates the visual state of the control by applying latest PseudoClasses.
-        /// </summary>
-        protected void UpdatePseudoClasses()
-        {
-            // Place the secondary button
-            //
-            // In WinUI, the span of the secondary button is changed to full-width for touch-based
-            // devices in certain conditions. The full reasoning for this is unknown. Some theories
-            // include:
-            //
-            //   My guess is that the design team at MS decided that it's a better experience
-            //   for touch users to make them select from the drop down rather than the shortcut
-            //   top level button, so touch basically just turns this into a drop down button.
-            //   Whether that's ideal or not is going is a subjective opinion.
-            //
-            // For Avalonia, it may not always make sense to disable the primary button like that
-            // on touch-first platforms. Users and developers would normally expect a control to
-            // function the same on all platforms. Therefore, this functionality is disabled here
-            // but could be re-enabled in the future if more reasons become known.
-            //
-            // Finally, these are mutually exclusive PseudoClasses handled separately from
-            // SetExclusivePseudoClass(). They must be applied in addition to the others.
-            /*
-            if (_lastPointerType == PointerType.Touch || _isKeyDown)
-            {
-                PseudoClasses.Set(pcSecondaryButtonSpan, true);
-                PseudoClasses.Set(pcSecondaryButtonRight, false);
-            }
-            else
-            {
-                PseudoClasses.Set(pcSecondaryButtonSpan, false);
-                PseudoClasses.Set(pcSecondaryButtonRight, true);
-            }
-            */
-
-            // Change the visual state
-            if (!IsEffectivelyEnabled)
-            {
-                SetExclusivePseudoClass(pcDisabled);
-            }
-            else if (_primaryButton != null && _secondaryButton != null)
-            {
-                if (_isFlyoutOpen)
-                {
-                    if (InternalIsChecked)
-                    {
-                        SetExclusivePseudoClass(pcCheckedFlyoutOpen);
-                    }
-                    else
-                    {
-                        SetExclusivePseudoClass(pcFlyoutOpen);
-                    }
-                }
-                // SplitButton and ToggleSplitButton share a template -- this section is driving the checked states for ToggleSplitButton.
-                else if (InternalIsChecked)
-                {
-                    if (_lastPointerType == PointerType.Touch || _isKeyDown)
-                    {
-                        if (_primaryButton.IsPressed || _secondaryButton.IsPressed || _isKeyDown)
-                        {
-                            SetExclusivePseudoClass(pcCheckedTouchPressed);
-                        }
-                        else
-                        {
-                            SetExclusivePseudoClass(pcChecked);
-                        }
-                    }
-                    else if (_primaryButton.IsPressed)
-                    {
-                        SetExclusivePseudoClass(pcCheckedPrimaryPressed);
-                    }
-                    else if (_primaryButton.IsPointerOver)
-                    {
-                        SetExclusivePseudoClass(pcCheckedPrimaryPointerOver);
-                    }
-                    else if (_secondaryButton.IsPressed)
-                    {
-                        SetExclusivePseudoClass(pcCheckedSecondaryPressed);
-                    }
-                    else if (_secondaryButton.IsPointerOver)
-                    {
-                        SetExclusivePseudoClass(pcCheckedSecondaryPointerOver);
-                    }
-                    else
-                    {
-                        SetExclusivePseudoClass(pcChecked);
-                    }
-                }
-                else
-                {
-                    if (_lastPointerType == PointerType.Touch || _isKeyDown)
-                    {
-                        if (_primaryButton.IsPressed || _secondaryButton.IsPressed || _isKeyDown)
-                        {
-                            SetExclusivePseudoClass(pcTouchPressed);
-                        }
-                        else
-                        {
-                            // Calling without a parameter is treated as ':normal' and will clear all other
-                            // PseudoClasses returning to the default state
-                            SetExclusivePseudoClass();
-                        }
-                    }
-                    else if (_primaryButton.IsPressed)
-                    {
-                        SetExclusivePseudoClass(pcPrimaryPressed);
-                    }
-                    else if (_primaryButton.IsPointerOver)
-                    {
-                        SetExclusivePseudoClass(pcPrimaryPointerOver);
-                    }
-                    else if (_secondaryButton.IsPressed)
-                    {
-                        SetExclusivePseudoClass(pcSecondaryPressed);
-                    }
-                    else if (_secondaryButton.IsPointerOver)
-                    {
-                        SetExclusivePseudoClass(pcSecondaryPointerOver);
-                    }
-                    else
-                    {
-                        // Calling without a parameter is treated as ':normal' and will clear all other
-                        // PseudoClasses returning to the default state
-                        SetExclusivePseudoClass();
-                    }
-                }
-            }
-
-            // Local function to enable the specified PseudoClass and disable all others
-            // This more closely matches the VisualStateManager of WinUI where the default style originated
-            void SetExclusivePseudoClass(string pseudoClass = "")
-            {
-                PseudoClasses.Set(pcDisabled, pseudoClass == pcDisabled);
-
-                PseudoClasses.Set(pcCheckedFlyoutOpen, pseudoClass == pcCheckedFlyoutOpen);
-                PseudoClasses.Set(pcFlyoutOpen,        pseudoClass == pcFlyoutOpen);
-
-                PseudoClasses.Set(pcCheckedTouchPressed,         pseudoClass == pcCheckedTouchPressed);
-                PseudoClasses.Set(pcChecked,                     pseudoClass == pcChecked);
-                PseudoClasses.Set(pcCheckedPrimaryPressed,       pseudoClass == pcCheckedPrimaryPressed);
-                PseudoClasses.Set(pcCheckedPrimaryPointerOver,   pseudoClass == pcCheckedPrimaryPointerOver);
-                PseudoClasses.Set(pcCheckedSecondaryPressed,     pseudoClass == pcCheckedSecondaryPressed);
-                PseudoClasses.Set(pcCheckedSecondaryPointerOver, pseudoClass == pcCheckedSecondaryPointerOver);
-
-                PseudoClasses.Set(pcTouchPressed,         pseudoClass == pcTouchPressed);
-                PseudoClasses.Set(pcPrimaryPressed,       pseudoClass == pcPrimaryPressed);
-                PseudoClasses.Set(pcPrimaryPointerOver,   pseudoClass == pcPrimaryPointerOver);
-                PseudoClasses.Set(pcSecondaryPressed,     pseudoClass == pcSecondaryPressed);
-                PseudoClasses.Set(pcSecondaryPointerOver, pseudoClass == pcSecondaryPointerOver);
-            }
-        }
-
-        /// <summary>
-        /// Opens the secondary button's flyout.
-        /// </summary>
-        protected void OpenFlyout()
-        {
-            if (Flyout != null)
-            {
-                Flyout.ShowAt(this);
-            }
-        }
-
-        /// <summary>
-        /// Closes the secondary button's flyout.
-        /// </summary>
-        protected void CloseFlyout()
-        {
-            if (Flyout != null)
-            {
-                Flyout.Hide();
-            }
-        }
-
-        /// <summary>
-        /// Registers all flyout events.
-        /// </summary>
-        /// <param name="flyout">The flyout to connect events to.</param>
-        private void RegisterFlyoutEvents(FlyoutBase flyout)
-        {
-            if (flyout != null)
-            {
-                flyout.Opened += Flyout_Opened;
-                flyout.Closed += Flyout_Closed;
-
-                _flyoutPropertyChangedDisposable = flyout.GetPropertyChangedObservable(FlyoutBase.PlacementProperty).Subscribe(Flyout_PlacementPropertyChanged);
-            }
-        }
-
-        /// <summary>
-        /// Explicitly unregisters all flyout events.
-        /// </summary>
-        /// <param name="flyout">The flyout to disconnect events from.</param>
-        private void UnregisterFlyoutEvents(FlyoutBase flyout)
-        {
-            if (flyout != null)
-            {
-                flyout.Opened -= Flyout_Opened;
-                flyout.Closed -= Flyout_Closed;
-
-                _flyoutPropertyChangedDisposable?.Dispose();
-                _flyoutPropertyChangedDisposable = null;
-             }
-        }
-
-        /// <summary>
-        /// Explicitly unregisters all events related to the two buttons in OnApplyTemplate().
-        /// </summary>
-        private void UnregisterEvents()
-        {
-            _buttonPropertyChangedDisposable?.Dispose();
-            _buttonPropertyChangedDisposable = null;
-
-            if (_primaryButton != null)
-            {
-                _primaryButton.Click -= PrimaryButton_Click;
-
-                _primaryButton.PointerEnter       -= Button_PointerEvent;
-                _primaryButton.PointerLeave       -= Button_PointerEvent;
-                _primaryButton.PointerPressed     -= Button_PointerEvent;
-                _primaryButton.PointerReleased    -= Button_PointerEvent;
-                _primaryButton.PointerCaptureLost -= Button_PointerCaptureLost;
-            }
-
-            if (_secondaryButton != null)
-            {
-                _secondaryButton.Click -= SecondaryButton_Click;
-
-                _secondaryButton.PointerEnter       -= Button_PointerEvent;
-                _secondaryButton.PointerLeave       -= Button_PointerEvent;
-                _secondaryButton.PointerPressed     -= Button_PointerEvent;
-                _secondaryButton.PointerReleased    -= Button_PointerEvent;
-                _secondaryButton.PointerCaptureLost -= Button_PointerCaptureLost;
-            }
-        }
-
-        ////////////////////////////////////////////////////////////////////////
-        // OnEvent Overridable Methods
-        ////////////////////////////////////////////////////////////////////////
-
-        /// <inheritdoc/>
-        protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
-        {
-            UnregisterEvents();
-            UnregisterFlyoutEvents(Flyout);
-
-            _primaryButton   = e.NameScope.Find<Button>("PART_PrimaryButton");
-            _secondaryButton = e.NameScope.Find<Button>("PART_SecondaryButton");
-
-            _buttonPropertyChangedDisposable = new CompositeDisposable();
-
-            if (_primaryButton != null)
-            {
-                _primaryButton.Click += PrimaryButton_Click;
-
-                _buttonPropertyChangedDisposable.Add(_primaryButton.GetPropertyChangedObservable(Button.IsPressedProperty).Subscribe(Button_VisualPropertyChanged));
-                _buttonPropertyChangedDisposable.Add(_primaryButton.GetPropertyChangedObservable(Button.IsPointerOverProperty).Subscribe(Button_VisualPropertyChanged));
-
-                // Register for pointer events to keep track of the last used pointer type and update visual states
-                _primaryButton.PointerEnter       += Button_PointerEvent;
-                _primaryButton.PointerLeave       += Button_PointerEvent;
-                _primaryButton.PointerPressed     += Button_PointerEvent;
-                _primaryButton.PointerReleased    += Button_PointerEvent;
-                _primaryButton.PointerCaptureLost += Button_PointerCaptureLost;
-            }
-
-            if (_secondaryButton != null)
-            {
-                _secondaryButton.Click += SecondaryButton_Click;
-
-                _buttonPropertyChangedDisposable.Add(_secondaryButton.GetPropertyChangedObservable(Button.IsPressedProperty).Subscribe(Button_VisualPropertyChanged));
-                _buttonPropertyChangedDisposable.Add(_secondaryButton.GetPropertyChangedObservable(Button.IsPointerOverProperty).Subscribe(Button_VisualPropertyChanged));
-
-                // Register for pointer events to keep track of the last used pointer type and update visual states
-                _secondaryButton.PointerEnter       += Button_PointerEvent;
-                _secondaryButton.PointerLeave       += Button_PointerEvent;
-                _secondaryButton.PointerPressed     += Button_PointerEvent;
-                _secondaryButton.PointerReleased    += Button_PointerEvent;
-                _secondaryButton.PointerCaptureLost += Button_PointerCaptureLost;
-            }
-
-            RegisterFlyoutEvents(Flyout);
-            UpdatePseudoClasses();
-
-            _hasLoaded = true;
-        }
-
-        /// <inheritdoc/>
-        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
-        {
-            base.OnAttachedToVisualTree(e);
-        }
-
-        /// <inheritdoc/>
-        protected override void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
-        {
-            base.OnDetachedFromVisualTree(e);
-        }
-
-        /// <inheritdoc/>
-        protected override void OnAttachedToLogicalTree(LogicalTreeAttachmentEventArgs e)
-        {
-            base.OnAttachedToLogicalTree(e);
-
-            if (Command != null)
-            {
-                Command.CanExecuteChanged += CanExecuteChanged;
-                CanExecuteChanged(this, EventArgs.Empty);
-            }
-
-            _isAttachedToLogicalTree = true;
-        }
-
-        /// <inheritdoc/>
-        protected override void OnDetachedFromLogicalTree(LogicalTreeAttachmentEventArgs e)
-        {
-            base.OnDetachedFromLogicalTree(e);
-
-            if (Command != null)
-            {
-                Command.CanExecuteChanged -= CanExecuteChanged;
-            }
-
-            _isAttachedToLogicalTree = false;
-        }
-
-        /// <inheritdoc/>
-        protected override void OnPropertyChanged<T>(AvaloniaPropertyChangedEventArgs<T> e)
-        {
-            if (e.Property == CommandProperty)
-            {
-                if (_isAttachedToLogicalTree)
-                {
-                    // Must unregister events here while a reference to the old command still exists
-                    if (e.OldValue.GetValueOrDefault() is ICommand oldCommand)
-                    {
-                        oldCommand.CanExecuteChanged -= CanExecuteChanged;
-                    }
-
-                    if (e.NewValue.GetValueOrDefault() is ICommand newCommand)
-                    {
-                        newCommand.CanExecuteChanged += CanExecuteChanged;
-                    }
-                }
-
-                CanExecuteChanged(this, EventArgs.Empty);
-            }
-            else if (e.Property == CommandParameterProperty)
-            {
-                CanExecuteChanged(this, EventArgs.Empty);
-            }
-            else if (e.Property == FlyoutProperty)
-            {
-                // Must unregister events here while a reference to the old flyout still exists
-                if (e.OldValue.GetValueOrDefault() is FlyoutBase oldFlyout)
-                {
-                    UnregisterFlyoutEvents(oldFlyout);
-                }
-
-                if (e.NewValue.GetValueOrDefault() is FlyoutBase newFlyout)
-                {
-                    RegisterFlyoutEvents(newFlyout);
-                }
-
-                UpdatePseudoClasses();
-            }
-
-            base.OnPropertyChanged(e);
-        }
-
-        /// <inheritdoc/>
-        protected override void OnKeyDown(KeyEventArgs e)
-        {
-            var key = e.Key;
-
-            if (key == Key.Space || key == Key.Enter) // Key.GamepadA is not currently supported
-            {
-                _isKeyDown = true;
-                UpdatePseudoClasses();
-            }
-
-            base.OnKeyDown(e);
-        }
-
-        /// <inheritdoc/>
-        protected override void OnKeyUp(KeyEventArgs e)
-        {
-            var key = e.Key;
-
-            if (key == Key.Space || key == Key.Enter) // Key.GamepadA is not currently supported
-            {
-                _isKeyDown = false;
-                UpdatePseudoClasses();
-
-                // Consider this a click on the primary button
-                if (IsEffectivelyEnabled)
-                {
-                    OnClickPrimary(null);
-                    e.Handled = true;
-                }
-            }
-            else if (key == Key.Down && IsEffectivelyEnabled)
-            {
-                // WinUI requires the VirtualKey.Menu (alt) + VirtualKey.Down to open the flyout
-                // Avalonia will only require Key.Down which is better cross-platform
-
-                OpenFlyout();
-                e.Handled = true;
-            }
-            else if (key == Key.F4 && IsEffectivelyEnabled)
-            {
-                OpenFlyout();
-                e.Handled = true;
-            }
-
-            base.OnKeyUp(e);
-        }
-
-        /// <summary>
-        /// Invokes the <see cref="Click"/> event when the primary button part is clicked.
-        /// </summary>
-        /// <param name="e">The event args from the internal Click event.</param>
-        protected virtual void OnClickPrimary(RoutedEventArgs e)
-        {
-            // Note: It is not currently required to check enabled status; however, this is a failsafe
-            if (IsEffectivelyEnabled)
-            {
-                var eventArgs = new RoutedEventArgs(ClickEvent);
-                RaiseEvent(eventArgs);
-
-                if (!eventArgs.Handled && Command?.CanExecute(CommandParameter) == true)
-                {
-                    Command.Execute(CommandParameter);
-                    eventArgs.Handled = true;
-                }
-            }
-        }
-
-        /// <summary>
-        /// Invoked when the secondary button part is clicked.
-        /// </summary>
-        /// <param name="e">The event args from the internal Click event.</param>
-        protected virtual void OnClickSecondary(RoutedEventArgs e)
-        {
-            // Note: It is not currently required to check enabled status; however, this is a failsafe
-            if (IsEffectivelyEnabled)
-            {
-                OpenFlyout();
-            }
-        }
-
-        ////////////////////////////////////////////////////////////////////////
-        // Event Handling
-        ////////////////////////////////////////////////////////////////////////
-
-        /// <summary>
-        /// Event handler for when the internal primary button part is pressed.
-        /// </summary>
-        private void PrimaryButton_Click(object sender, RoutedEventArgs e)
-        {
-            OnClickPrimary(e);
-        }
-
-        /// <summary>
-        /// Event handler for when the internal secondary button part is pressed.
-        /// </summary>
-        private void SecondaryButton_Click(object sender, RoutedEventArgs e)
-        {
-            OnClickSecondary(e);
-        }
-
-        /// <summary>
-        /// Event handler for when pointer events occur in the primary or secondary buttons.
-        /// </summary>
-        private void Button_PointerEvent(object sender, PointerEventArgs e)
-        {
-            // Warning: Code must match with Button_PointerCaptureLost
-            if (_lastPointerType != e.Pointer.Type)
-            {
-                _lastPointerType = e.Pointer.Type;
-                UpdatePseudoClasses();
-            }
-        }
-
-        /// <summary>
-        /// Event handler for when the pointer capture is lost in the primary or secondary buttons.
-        /// </summary>
-        /// <remarks>
-        /// In upstream WinUI this is not a separate event handler. However, Avalonia has different args.
-        /// </remarks>
-        private void Button_PointerCaptureLost(object sender, PointerCaptureLostEventArgs e)
-        {
-            // Warning: Code must match with Button_PointerEvent
-            if (_lastPointerType != e.Pointer.Type)
-            {
-                _lastPointerType = e.Pointer.Type;
-                UpdatePseudoClasses();
-            }
-        }
-
-        /// <summary>
-        /// Called when a primary or secondary button property changes that affects the visual states.
-        /// </summary>
-        private void Button_VisualPropertyChanged(AvaloniaPropertyChangedEventArgs e)
-        {
-            UpdatePseudoClasses();
-        }
-
-        /// <summary>
-        /// Called when the <see cref="FlyoutBase.Placement"/> property changes.
-        /// </summary>
-        private void Flyout_PlacementPropertyChanged(AvaloniaPropertyChangedEventArgs e)
-        {
-            UpdatePseudoClasses();
-        }
-
-        /// <summary>
-        /// Event handler for when the split button's flyout is opened.
-        /// </summary>
-        private void Flyout_Opened(object sender, EventArgs e)
-        {
-            var flyout = sender as FlyoutBase;
-
-            // It is possible to share flyouts among multiple controls including SplitButton.
-            // This can cause a problem here since all controls that share a flyout receive
-            // the same Opened/Closed events at the same time.
-            // For SplitButton that means they all would be updating their pseudoclasses accordingly.
-            // In other words, all SplitButtons with a shared Flyout would have the backgrounds changed together.
-            // To fix this, only continue here if the Flyout target matches this SplitButton instance.
-            if (object.ReferenceEquals(flyout?.Target, this))
-            {
-                _isFlyoutOpen = true;
-                UpdatePseudoClasses();
-            }
-        }
-
-        /// <summary>
-        /// Event handler for when the split button's flyout is closed.
-        /// </summary>
-        private void Flyout_Closed(object sender, EventArgs e)
-        {
-            var flyout = sender as FlyoutBase;
-
-            // See comments in Flyout_Opened
-            if (object.ReferenceEquals(flyout?.Target, this))
-            {
-                _isFlyoutOpen = false;
-                UpdatePseudoClasses();
-            }
-        }
-    }
-}