Use [PrivateApi] on members

src/Avalonia.Base/Input/FocusManager.cs

@@ -11,7 +11,7 @@ namespace Avalonia.Input
     /// <summary>
     /// Manages focus for the application.
     /// </summary>
-    [Unstable]
+    [PrivateApi]
     public class FocusManager : IFocusManager
     {
         /// <summary>

src/Avalonia.Base/Input/KeyboardDevice.cs

@@ -7,7 +7,7 @@ using Avalonia.Metadata;
 
 namespace Avalonia.Input
 {
-    [Unstable]
+    [PrivateApi]
     public class KeyboardDevice : IKeyboardDevice, INotifyPropertyChanged
     {
         private IInputElement? _focusedElement;

src/Avalonia.Base/Input/MouseDevice.cs

@@ -12,7 +12,7 @@ namespace Avalonia.Input
     /// <summary>
     /// Represents a mouse device.
     /// </summary>
-    [Unstable]
+    [PrivateApi]
     public class MouseDevice : IMouseDevice, IDisposable
     {
         private int _clickCount;

src/Avalonia.Base/Input/PenDevice.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
 using Avalonia.Input.Raw;
+using Avalonia.Metadata;
 using Avalonia.Platform;
 #pragma warning disable CS0618
 
@@ -11,6 +12,7 @@ namespace Avalonia.Input
     /// <summary>
     /// Represents a pen/stylus device.
     /// </summary>
+    [PrivateApi]
     public class PenDevice : IPenDevice, IDisposable
     {
         private readonly Dictionary<long, Pointer> _pointers = new();

src/Avalonia.Base/Input/TouchDevice.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
 using Avalonia.Input.Raw;
+using Avalonia.Metadata;
 using Avalonia.Platform;
 #pragma warning disable CS0618
 
@@ -14,6 +15,7 @@ namespace Avalonia.Input
     /// <remarks>
     /// This class is supposed to be used on per-toplevel basis, don't use a shared one
     /// </remarks>
+    [PrivateApi]
     public class TouchDevice : IPointerDevice, IDisposable
     {
         private readonly Dictionary<long, Pointer> _pointers = new Dictionary<long, Pointer>();