FocusManager.FocusedElement 无法让 NumericUpDown 聚焦

[qianshipoi]

Describe the bug

使用 FocusManager.FocusedElement 没有办法让 NumericUpDown 一开始就聚焦

Steps to reproduce the bug

代码

 <Window
    x:Class="WpfApp6.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:hc="https://handyorg.github.io/handycontrol"
    xmlns:local="clr-namespace:WpfApp6"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    Title="MainWindow"
    Width="800"
    Height="450"
    FocusManager.FocusedElement="{Binding ElementName=Input}"
    mc:Ignorable="d">

    <Grid>
        <hc:NumericUpDown
            x:Name="Input" Focusable="True"
            Width="120"
            VerticalAlignment="Center" />
    </Grid>
 </Window>

Expected behavior

应该会在窗口打开时自动聚焦到文本框

Screenshots

No response

NuGet package version

HandyControl 3.5.1

IDE

Visual Studio 2022-preview

Framework type

.Net 9.0

Windows version

No response

Additional context

No response