Caption Height for Custom Pane Header



I modified AnchorablePaneControlStyle in my DockManager to customize my pane header.
It works and the header is bigger now (like I want, see attached pics).

But there is an issue regarding the header caption area when undocking.
Obviously, the caption area is related to textbox control inside the AnchorableTitleTemplate, I mean I can only undock from a position inside text box.
It means if I want to center my textbox (and this is what I want to do, see attached pics), the textbox control is resized and I can t undock from outside textbox area.

I tried to put textbox in a grid modifying AnchorableTitleTemplate but nothings changes.

I modified AnchorableControlStyle to have my custom header
<Border Background="WhiteSmoke" Border.Name="Header" Height="48">
    <xcad:AnchorablePaneTitle Height="{TemplateBinding Height}" Foreground="Gray" FontSize="22" Style="{StaticResource AnchorablePaneTitleStyle}" Model="{Binding Model,RelativeSource={RelativeSource TemplatedParent}}" xmlns:avalonDockControls="clr-namespace:Xceed.Wpf.AvalonDock.Controls;assembly=Xceed.Wpf.AvalonDock,Version=3.0.16572.0,Culture=neutral,PublicKeyToken=ba83ff368b7563c6" />
How can I solve that please ?

Thanks in advance

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