Keyboard focus navigation in list of items embedded in ScrollViewer causes pointer events to stop working

[rozele]

Describe the bug

When keyboard navigating (tabbing) between tab-stop ContentControl items in a list rendered in a ScrollViewer, pointer events stop flowing to the app. It seems that the app stops responding to any mouse events.

Steps to reproduce the bug

The following source code reproduces the issue:

  winrt::Microsoft::UI::Xaml::Window window;

  winrt::Microsoft::UI::Xaml::Controls::ScrollViewer rootView;
  winrt::Microsoft::UI::Xaml::Controls::StackPanel content;
  rootView.Content(content);
  
  for (auto i = 0; i < 100; ++i) {
    winrt::Microsoft::UI::Xaml::Controls::TextBlock item;
    item.Text(winrt::hstring{L"Item "} + winrt::to_hstring(i));
    winrt::Microsoft::UI::Xaml::Controls::Grid grid;
    grid.Padding(winrt::Microsoft::UI::Xaml::Thickness{5, 5, 5, 5});
    grid.Children().Append(item);
    grid.PointerEntered([item](auto&&...) {

      item.FontWeight(winrt::Windows::UI::Text::FontWeight{winrt::Windows::UI::Text::FontWeights::Bold()});
    });
    grid.PointerExited([item](auto&&...) {
      item.FontWeight(winrt::Windows::UI::Text::FontWeight{winrt::Windows::UI::Text::FontWeights::Normal()});
    });
    winrt::Microsoft::UI::Xaml::Controls::ContentControl control;
    control.Content(grid);
    control.IsTabStop(true);
    control.UseSystemFocusVisuals(true);
    content.Children().Append(control);
  }

  window.Content(rootView);
  window.Activate();

After launching the app, if I rapidly press the Tab key (or hold the Tab key), while moving the mouse over the items in the list, it eventually gets into a state where the pointer events stop firing on the items.

The app starts responding to pointer events again after pressing any key (other than Tab).

Expected behavior

The app should continue to respond to mouse events after tab navigation stops.

Screenshots

WinUI.Desktop.2025-03-25.15-17-48.mp4

NuGet package version

Windows App SDK 1.7.0: 1.7.250310001

Packaging type

Unpackaged

Windows version

Windows 10 version 22H2 (19045)

IDE

Other

Additional context

No response

[lgBlog]

On any page, long pressing the TAB key will cause the UI interface to freeze

[ayushjai30]

Hi @rozele, this issue has been resolved in WinAppSDK version 1.7.1 (1.7.250401001). I was able to reproduce it in version 1.7.0, but not in 1.7.1. Please update your Windows App SDK to the latest version to avoid this issue.
cc: @AjitSurana @chrisglein