aistudio-wpf-diagram/Fluent.Ribbon/Fluent.Ribbon.Showcase/RibbonWindowWithoutVisibleRibbon.xaml

<fluent:RibbonWindow x:Class="FluentTest.RibbonWindowWithoutVisibleRibbon"
                     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:fluent="urn:fluent-ribbon"
                     Title="RibbonWindowWithoutRibbon"
                     Height="300"
                     Width="300">
    <Grid>
        <fluent:Ribbon IsMinimized="True"
                       IsAutomaticCollapseEnabled="False"
                       IsCollapsed="True"
                       IsQuickAccessToolBarVisible="False"
                       CanCustomizeQuickAccessToolBar="False"
                       CanCustomizeRibbon="False"
                       CanQuickAccessLocationChanging="False"
                       ContentGapHeight="2" />
    </Grid>
</fluent:RibbonWindow>