Stretching out the Listbox content.
In order to get the content of my Listbox ItemTemplate to fill out the entire width of the Listbox control, I simply needed to add an ItemContainerStyle as follows:
<UserControl.Resources>
<Style x:Key="ListBoxItemStyle1" TargetType="ListBoxItem">
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Setter Property="HorizontalAlignment" Value="Stretch"/>
</Style>
</UserControl.Resources>
The solution came from here…
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