Maximize before Activate causes top edge glitch for Windows with ExtendsContentIntoTitleBar set to true.

[riyasy]

If we call Maximize before Activate (I am not sure whether it is legal),
the window appears slightly expanded and then settles into the maximized rect. This causes a visual glitch.

This only happens if ExtendsContentIntoTitleBar is true.

using Microsoft.UI.Xaml;
using WinUIEx;

namespace WinUiMaximizedTest;

public partial class App : Application
{
    private MainWindow? _window;

    public App() => InitializeComponent();

    protected override void OnLaunched(LaunchActivatedEventArgs args)
    {
        _window = new MainWindow();
        _window.Maximize();
        _window.Activate();
    }
}

using Microsoft.UI;
using Microsoft.UI.Xaml;

namespace WinUiMaximizedTest;

public sealed partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();

        var titleBar = AppWindow.TitleBar;
        titleBar.ExtendsContentIntoTitleBar = true;
        titleBar.ButtonBackgroundColor = Colors.Transparent;
        titleBar.ButtonInactiveBackgroundColor = Colors.Transparent;
    }
}

Observe the top most portion. Video from one of my users.

02.mp4