Wrong position of Tooltip of WPF controls in Windows 10

Question

I find the position of ToolTip on some WPF controls is not correct on some computers, all drift left(even after set the Placement to Right), so I create a WPF project(.net framework 4.6.1) to show this, simply has a TextBlock in MainWindow. Do you konw the reason of this strange act? How to correct it? Code:

<Window x:Class="NormalToolTipDemo.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:NormalToolTipDemo"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <StackPanel>            
            <TextBlock Text="TextBlock" ToolTip="TextBlock" ToolTipService.Placement="Right" Margin="20" HorizontalAlignment="Center"/>
        </StackPanel>
    </Grid>
</Window>

Normal image:

Abnormal image:

The related system configuration of abnormal tooltip:

Answer 1

Check if the behaviour depends on some settings in Control Panel or Registry: https://github.com/dotnet/wpf/issues/5944. The computer probably must be restarted.