AtomUI/tests/AtomUI.Desktop.Controls.Tests/Menu/MenuSemanticReuseView.axaml

<UserControl xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:atom="https://atomui.net"
             x:Class="AtomUI.Desktop.Controls.Tests.Menu.MenuSemanticReuseView">
    <UserControl.Styles>
        <Style Selector="atom|DropdownButton">
            <atom:DropdownButtonItemStyle x:SetterTargetType="atom:MenuItem">
                <Setter Property="Tag" Value="dropdown-item" />
                <Setter Property="Foreground" Value="Red" />
            </atom:DropdownButtonItemStyle>
        </Style>
    </UserControl.Styles>
    <atom:DropdownButton Name="Button" Content="Menu" IsMotionEnabled="False" />
</UserControl>