Visual artifacts with .NET Core 3.1

[realflight1]

I created a new WPF .NET Core project using VS2019 and followed the quick start instructions in the README. When running the application I get the following (GIF):

I am seeing similar issues with UseModernWindowStyle="False". Is .NET Core 3.1 supported?

My code -

App.xaml

<Application x:Class="WpfApp1.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:ui="http://schemas.modernwpf.com/2019"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ui:ThemeResources />
                <ui:XamlControlsResources />
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>
</Application>

MainWindow.xaml

<Window x:Class="WpfApp1.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:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp1"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800"
        xmlns:ui="http://schemas.modernwpf.com/2019"
        ui:WindowHelper.UseModernWindowStyle="True">
    <ui:SimpleStackPanel Margin="12" Spacing="24">
        <TextBlock Text="My first ModernWPF app" Style="{StaticResource HeaderTextBlockStyle}" />
        <Button Content="I am a button" />
        <Button Content="I am an accent button" Style="{StaticResource AccentButtonStyle}" />
    </ui:SimpleStackPanel>
</Window>

[realflight1]

Closing this as the issue is caused by external software, in my case Sonic Suite.
For more details see dotnet/wpf#707

[rocuh]

Just for anyone who finds this as mentioned in dotnet/wpf#707 you can set:

AllowsTransparency="True" WindowStyle="None" ui:WindowHelper.UseModernWindowStyle="True"

and that stops the corruption from occuring (at least for Nahimic DLL inject), some motherboard manufacturer install this with there realtek audio drivers. I've tested the audio drivers (Version 6.0.1.8496) for the ROG STRIX X370-F motherboard and it corrupts if the above is not set.

[DanielHoltebo]

Closing this as the issue is caused by external software, in my case Sonic Suite.
For more details see dotnet/wpf#707

^This solved all my issues @realflight1, also had the same problems with a Java application but deleting Sonic Suite solved everything! :D