[Desktop] x:Bind local does not work in Custom Control

[kucint]

Current behavior

Issue 1 binding to local constant works in Page but not working in Control

<Grid
  Width="{x:Bind local:MyControl.MyWidth}"
  Height="{x:Bind local:MyControl.MyHeight}" />

Code behind:

public sealed partial class MyControl : Control
{
    public const double MyWidth = 200;
    public const double MyHeight = 200;
}

Issue 2

Discrepancy between WinAppSDK and Desktop: WinAppSDK works fine with private const while Desktop requires public const

WinAppSDK

public sealed partial class MyControl : Control
{
    private const double MyWidth = 200;
    private const double MyHeight = 200;
}

Desktop

public sealed partial class MyControl : Control
{
    public const double MyWidth = 200;
    public const double MyHeight = 200;
}

Expected behavior

binding to local constant shall work in Control

How to reproduce it (as minimally and precisely as possible)

MINIMAL REPRO PROJECT: XBindLocalApp.zip

STEPS TO REPRODUCE: run the app on Windows with WinAppSDK framework selected: all works fine:

run the app on Windows with Desktop framework selected: binding works in Page but fails in Control

Workaround

define constant in XAML rather than in C# code behind

Works on UWP/WinUI

Yes

Environment

No response

NuGet package version(s)

"Uno.Sdk": "5.4.8"

Affected platforms

Skia (WPF)

IDE

Visual Studio 2022

IDE version

No response

Relevant plugins

No response

Anything else we need to know?

No response