WPF XAML TextBox not editable after applying Control Template - wpf

Question

I have a TextBox in WPF and I'm trying to make the border color change when the mouse hovers over the TextBox. Based on my experience with other elements in WPF, I need to insert a ControlTemplate value with TemplateBinding to the values I am trying to dynamically change. However, when I apply this, the box becomes uneditable (and the text disappears). If I remove the Template setter, the box becomes editable again, but the custom BorderBrush triggers do not work.
Here is the Style:
<Style x:Key="TextBoxBase" TargetType="TextBox">
<Setter Property="FontSize" Value="30"/>
<Setter Property="Background" Value="{StaticResource BrushLightGrey}"/>
<Setter Property="Foreground" Value="{StaticResource BrushNormalText}"/>
<Setter Property="IsReadOnly" Value="False"/>
<Setter Property="Height" Value="40"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<Border BorderBrush="{TemplateBinding BorderBrush}">
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="BorderBrush" Value="{StaticResource BrushBlue}"/>
</Trigger>
</Style.Triggers>
<Style.Resources>
<Style TargetType="{x:Type Border}">
<Setter Property="CornerRadius" Value="5"/>
</Style>
</Style.Resources>
</Style>
Any suggestions or help is appreciated. Thanks.

Answer 1

You missed out the critical part:
<ScrollViewer Margin="0"
x:Name="PART_ContentHost" />
This is what hosts the text.
See
https://learn.microsoft.com/en-us/dotnet/framework/wpf/controls/textbox-styles-and-templates
TextBox Parts
The following table lists the named parts for the TextBox control.
TEXTBOX PARTS
Part Type Description
PART_ContentHost FrameworkElement A visual element that can contain a FrameworkElement. The text of the TextBox is displayed in this element.