Subtle Blurriness in `StackPanel` Inside `ScrollView` or `ScrollViewer` When Maximized

Describe the bug

When a StackPanel is placed inside a ScrollView or ScrollViewer, changing its visual properties (e.g., setting MaxWidth) can cause a slight blurriness issue when the window is maximized. This issue is subtle and difficult to notice but affects text and UI clarity.

Steps to reproduce the bug

Refer to the discussion and fix in this PR: https://github.com/microsoft/WinUI-Gallery/pull/1801

Expected behavior

The contents inside the StackPanel should remain sharp and clear, regardless of window resizing or maximizing.

Screenshots

The issue is hard to capture in screenshots, as it requires deep observation while resizing or maximizing the window.

NuGet package version

WinUI 3 - Windows App SDK 1.6.5: 1.6.250205002

Windows version

Windows 11 (23H2): Build 22631

Additional context

• This issue does not occur when the visual properties of StackPanel, such as MaxWidth, are not set.
• To work around this issue, I wrapped the StackPanel inside a Border, which resolved the blurriness without requiring significant changes to the layout.

Start by reproducing the StackPanel inside a ScrollView or ScrollViewer with MaxWidth set, using Windows App SDK 1.6.5 on Windows 11 23H2, then compare behavior while resizing and maximizing. Read the discussion and proposed fix in PR #1801; done means the contents remain sharp without requiring the Border workaround.