ClipCMD/ClipCMD/MainWindow.xaml

<Window x:Class="ClipCMD.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:ClipCMD"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <DockPanel>
        <StackPanel DockPanel.Dock="Top" Orientation="Horizontal">
            <Label Content="Prefix" />
            <TextBox x:Name="prefixTextBox" KeyUp="FixTextBox_TextChanged" Text="01" />
        </StackPanel>
        <StackPanel DockPanel.Dock="Top" Orientation="Horizontal">
            <Label Content="Suffix" />
            <TextBox x:Name="suffixTextBox" KeyUp="FixTextBox_TextChanged" Text="01" />
        </StackPanel>

        <Grid DockPanel.Dock="Top" VerticalAlignment="Stretch">
            <Grid.ColumnDefinitions>
                <ColumnDefinition />
                <ColumnDefinition />
            </Grid.ColumnDefinitions>

            <DockPanel Grid.Column="0">
                <Label DockPanel.Dock="Top" Content="Static Commands:" />
                <TextBox DockPanel.Dock="Top" x:Name="staticCommandsTextBox" TextChanged="StaticCommandsTextBox_TextChanged" TextWrapping="Wrap" AcceptsReturn="True" VerticalAlignment="Stretch" />
            </DockPanel>

            <DockPanel Grid.Column="1">
                <Label DockPanel.Dock="Top" Content="History:" />
                <ListBox DockPanel.Dock="Top"  x:Name="logListBox" VerticalAlignment="Stretch" />
            </DockPanel>
        </Grid>
    </DockPanel>
</Window>