PicView/PicView/Views/ContextMenus/WindowContextMenu.xaml

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

    <ContextMenu x:Key="windowCM">

        <!--  Fullscreen  -->
        <MenuItem Foreground="{StaticResource MainColorBrush}" Header="{StaticResource ToggleFullscreen}">
            <MenuItem.Icon>
                <Image Width="17" Height="17">
                    <Image.Source>
                        <DrawingImage>
                            <DrawingImage.Drawing>
                                <DrawingGroup ClipGeometry="M0,0 V24 H24 V0 H0 Z">
                                    <GeometryDrawing Brush="{StaticResource IconColorBrush}" Geometry="F1 M24,24z M0,0z M4,8L8,8 8,4 20,4 20,16 16,16 16,20 4,20 4,8 M16,8L16,14 18,14 18,6 10,6 10,8 16,8 M6,12L6,18 14,18 14,12 6,12z" />
                                </DrawingGroup>
                            </DrawingImage.Drawing>
                        </DrawingImage>
                    </Image.Source>
                </Image>
            </MenuItem.Icon>
        </MenuItem>

        <!--  Minimize  -->
        <MenuItem Foreground="{StaticResource MainColorBrush}" Header="{StaticResource Minimize}">
            <MenuItem.Icon>
                <Viewbox Width="14" Height="14">
                    <Path Data="M24,11c0-0.6-0.4-1-1-1H1c-0.6,0-1,0.4-1,1v2c0,0.6,0.4,1,1,1h22c0.6,0,1-0.4,1-1V11z" Fill="{StaticResource IconColorBrush}" />
                </Viewbox>
            </MenuItem.Icon>
        </MenuItem>

        <!--  Close  -->
        <MenuItem
            Foreground="{StaticResource MainColorBrush}"
            Header="{StaticResource Close}"
            InputGestureText="{StaticResource Esc}"
            ToolTip="{StaticResource CloseApp}">
            <MenuItem.Icon>
                <Path
                    Width="12"
                    Height="12"
                    Data="M443.6,387.1L312.4,255.4l131.5-130c5.4-5.4,5.4-14.2,0-19.6l-37.4-37.6c-2.6-2.6-6.1-4-9.8-4c-3.7,0-7.2,1.5-9.8,4  L256,197.8L124.9,68.3c-2.6-2.6-6.1-4-9.8-4c-3.7,0-7.2,1.5-9.8,4L68,105.9c-5.4,5.4-5.4,14.2,0,19.6l131.5,130L68.4,387.1  c-2.6,2.6-4.1,6.1-4.1,9.8c0,3.7,1.4,7.2,4.1,9.8l37.4,37.6c2.7,2.7,6.2,4.1,9.8,4.1c3.5,0,7.1-1.3,9.8-4.1L256,313.1l130.7,131.1  c2.7,2.7,6.2,4.1,9.8,4.1c3.5,0,7.1-1.3,9.8-4.1l37.4-37.6c2.6-2.6,4.1-6.1,4.1-9.8C447.7,393.2,446.2,389.7,443.6,387.1z"
                    Fill="{StaticResource IconColorBrush}"
                    Stretch="Fill" />
            </MenuItem.Icon>
        </MenuItem>
    </ContextMenu>
</ResourceDictionary>