EditableTab.xaml

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

    <SolidColorBrush x:Key="Item.MouseOver.Background" Color="Transparent"/>
    <SolidColorBrush x:Key="Item.MouseOver.Foreground" Color="White"/>
    <SolidColorBrush x:Key="Item.MouseOver.Border" Color="Black"/>

    <SolidColorBrush x:Key="Item.SelectedInactive.Background" Color="#FF3B3B3B"/>
    <SolidColorBrush x:Key="Item.SelectedInactive.Foreground" Color="White"/>
    <SolidColorBrush x:Key="Item.SelectedInactive.Border" Color="Black"/>

    <SolidColorBrush x:Key="Item.SelectedActive.Background" Color="White"/>
    <SolidColorBrush x:Key="Item.SelectedActive.Foreground" Color="Black"/>
    <SolidColorBrush x:Key="Item.SelectedActive.Border" Color="Black"/>
    <Style x:Key="EditableTabTabItemStyle" TargetType="{x:Type TabItem}">
        <Setter Property="FocusVisualStyle">
            <Setter.Value>
                <Style>
                    <Setter Property="Control.Template">
                        <Setter.Value>
                            <ControlTemplate>
                                <Rectangle Margin="2" SnapsToDevicePixels="True" 
                                                   Stroke="{StaticResource {x:Static SystemColors.ControlTextBrushKey}}" 
                                                   StrokeThickness="1" StrokeDashArray="1 2"/>
                            </ControlTemplate>
                        </Setter.Value>
                    </Setter>
                </Style>
            </Setter.Value>
        </Setter>
        <Setter Property="FontSize" Value="30"/>
        <Setter Property="Foreground" Value="{StaticResource Item.SelectedInactive.Foreground}"/>
        <Setter Property="Background" Value="{StaticResource Item.SelectedInactive.Background}"/>
        <Setter Property="BorderBrush" Value="{StaticResource Item.SelectedInactive.Border}"/>
        <Setter Property="Margin" Value="0"/>
        <Setter Property="Padding" Value="30,10"/>
        <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
        <Setter Property="VerticalContentAlignment" Value="Stretch"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type TabItem}">
                    <Grid x:Name="templateRoot" SnapsToDevicePixels="True">
                        <Border x:Name="mainBorder" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="1,1,1,0" Background="{TemplateBinding Background}" Margin="0"/>

                        <ContentPresenter x:Name="contentPresenter" ContentTemplate="{TemplateBinding HeaderTemplate}" Content="{TemplateBinding Header}" ContentStringFormat="{TemplateBinding HeaderStringFormat}" ContentSource="Header" Focusable="False" HorizontalAlignment="{Binding HorizontalContentAlignment, RelativeSource={RelativeSource FindAncestor, AncestorLevel=1, AncestorType={x:Type ItemsControl}}}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{Binding VerticalContentAlignment, RelativeSource={RelativeSource FindAncestor, AncestorLevel=1, AncestorType={x:Type ItemsControl}}}"/>
                    </Grid>
                    <ControlTemplate.Triggers>
                        <MultiDataTrigger>
                            <MultiDataTrigger.Conditions>
                                <Condition Binding="{Binding IsMouseOver, RelativeSource={RelativeSource Self}}" Value="true"/>
                            </MultiDataTrigger.Conditions>
                            <Setter Property="Background" Value="{StaticResource Item.MouseOver.Background}"/>
                            <Setter Property="Foreground" Value="{StaticResource Item.MouseOver.Foreground}"/>
                            <Setter Property="BorderBrush" Value="{StaticResource Item.MouseOver.Border}"/>
                        </MultiDataTrigger>

                        <MultiDataTrigger>
                            <MultiDataTrigger.Conditions>
                                <Condition Binding="{Binding IsSelected, RelativeSource={RelativeSource Self}}" Value="false"/>
                            </MultiDataTrigger.Conditions>
                            <Setter Property="Background" Value="{StaticResource Item.SelectedInactive.Background}"/>
                            <Setter Property="Foreground" Value="{StaticResource Item.SelectedInactive.Foreground}"/>
                            <Setter Property="BorderBrush" Value="{StaticResource Item.SelectedInactive.Border}"/>
                        </MultiDataTrigger>
                        <MultiDataTrigger>
                            <MultiDataTrigger.Conditions>
                                <Condition Binding="{Binding IsSelected, RelativeSource={RelativeSource Self}}" Value="true"/>
                            </MultiDataTrigger.Conditions>
                            <Setter Property="Panel.ZIndex" Value="1"/>
                            <Setter Property="Background" Value="{StaticResource Item.SelectedActive.Background}"/>
                            <Setter Property="Foreground" Value="{StaticResource Item.SelectedActive.Foreground}"/>
                            <Setter Property="BorderBrush" Value="{StaticResource Item.SelectedActive.Border}"/>
                        </MultiDataTrigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <Style x:Key="EditableTabStyle" TargetType="{x:Type TabControl}">
        <Setter Property="Padding" Value="2"/>
        <Setter Property="HorizontalContentAlignment" Value="Center"/>
        <Setter Property="VerticalContentAlignment" Value="Center"/>
        <Setter Property="BorderThickness" Value="1"/>
        <Setter Property="Foreground" Value="{StaticResource {x:Static SystemColors.ControlTextBrushKey}}"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type TabControl}">
                    <Grid x:Name="templateRoot" ClipToBounds="true" SnapsToDevicePixels="true" KeyboardNavigation.TabNavigation="Local">
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition x:Name="ColumnDefinition0"/>
                            <ColumnDefinition x:Name="ColumnDefinition1" Width="0"/>
                        </Grid.ColumnDefinitions>
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition x:Name="RowDefinition1" Height="*"/>
                        </Grid.RowDefinitions>
                        <TabPanel x:Name="headerPanel" VerticalAlignment="Bottom" Background="Transparent" Grid.Column="0" IsItemsHost="true" KeyboardNavigation.TabIndex="1" Panel.ZIndex="1"/>
                        <Border x:Name="contentPanel" Background="{TemplateBinding Background}" Grid.Column="0" KeyboardNavigation.DirectionalNavigation="Contained" Grid.Row="1" KeyboardNavigation.TabIndex="2" KeyboardNavigation.TabNavigation="Local">
                            <ContentPresenter x:Name="PART_SelectedContentHost" ContentSource="SelectedContent" Margin="{TemplateBinding Padding}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
                        </Border>
                    </Grid>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsEnabled" Value="false">
                            <Setter Property="TextElement.Foreground" TargetName="templateRoot" Value="{StaticResource {x:Static SystemColors.GrayTextBrushKey}}"/>
                        </Trigger>
                    </ControlTemplate.Triggers>
                    
                </ControlTemplate>
            </Setter.Value>
        </Setter>
        <Setter Property="ItemContainerStyle" Value="{StaticResource EditableTabTabItemStyle}"/>
    </Style>
</ResourceDictionary>