Application hangs when scrolling

[AmelBawa-msft]

Describe the bug

I noticed this bug when working on a similar scenario in Dev Home when scrolling inside a ScrollViewer containing a nested ItemsRepeater, the application consistently hangs indefinitely.

Steps to reproduce the bug

I am able to repro with the following code:

MainWindow.xaml

<Window>
    <ScrollViewer>
        <ItemsRepeater ItemsSource="{x:Bind Items}">
            <ItemsRepeater.ItemTemplate>
                <DataTemplate>
                    <ItemsRepeater ItemsSource="{Binding}">
                        <ItemsRepeater.Layout>
                            <UniformGridLayout
                                Orientation="Horizontal"
                                MinItemWidth="150"
                                MaximumRowsOrColumns="3"
                                MinRowSpacing="4"
                                MinColumnSpacing="4"
                                MinItemHeight="150"
                                ItemsStretch="Fill" />
                        </ItemsRepeater.Layout>
                        <ItemsRepeater.ItemTemplate>
                            <DataTemplate>
                                <TextBlock Text="{Binding}" />
                            </DataTemplate>
                        </ItemsRepeater.ItemTemplate>
                    </ItemsRepeater>
                </DataTemplate>
            </ItemsRepeater.ItemTemplate>
        </ItemsRepeater>
    </ScrollViewer>
</Window>

MainWindow.xaml.cs

    public sealed partial class MainWindow : Window
    {
        public List<List<int>> Items = Enumerable.Range(0, 10).Select(_ => Enumerable.Range(1, 6).ToList()).ToList();
            

        public MainWindow()
        {
            this.InitializeComponent();
        }
    }

Expected behavior

No response

Screenshots

1. Start scrolling
2. Application hangs

NuGet package version

WinUI 3 - Windows App SDK 1.4.3: 1.4.231115000

Windows version

Windows 11 (22H2): Build 22621

Additional context

No response