Through Nuget install the Dirkster.AvalonDock 4.5 and its in the reference
Here is my xaml code for the mainwindow

```
<Window x:Class="AvalonDocTestApp.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:AvalonDocTestApp"
            mc:Ignorable="d"
            Title="MainWindow" Height="450" Width="800">
        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*"/>
                <ColumnDefinition Width="*"/>
            </Grid.ColumnDefinitions>
            <StackPanel Grid.Column="0">
                <local:UserControl1/>
            </StackPanel>
            <Grid Grid.Column="1">
                <DockingManager Grid.Row="1" x:Name="dockManager" AllowMixedOrientation="True">
                    <LayoutRoot>
                    <LayoutPanel Orientation="Horizontal">
                    <LayoutAnchorablePaneGroup DockWidth="150">
                        <LayoutAnchorablePane>
                            <LayoutAnchorable ContentId="toolWindow1" Title="Tool Window 1" >
                                        <StackPanel>
                                            <TextBox Text="{Binding TestTimer, Mode=OneWay, StringFormat='Tool Window 1 Attached to Timer ->\{0\}'}"/>
                                        </StackPanel>
                            </LayoutAnchorable>
                        </LayoutAnchorablePane>
                    </LayoutAnchorablePaneGroup>
                    </LayoutPanel>
                    </LayoutRoot>
                </DockingManager>
            </Grid>    
        </Grid>
    </Window> 

```

The above code for the LayoutAnchorable section textbox appears without any title and dock combobutton