I have a grid that looks like follow:

 <Grid Grid.Column="0" Grid.Row="0" Margin="20,50,10,10"> <Grid.RowDefinitions> <RowDefinition Height="*" /> <RowDefinition Height="*" /> <RowDefinition Height="*" /> <RowDefinition Height="*" /> <RowDefinition Height="0.5*" /> <RowDefinition Height="*" /> </Grid.RowDefinitions> <Grid.ColumnDefinitions> <ColumnDefinition Width="*" /> <ColumnDefinition Width="*" /> </Grid.ColumnDefinitions> </Grid>

And inside the grid, I place a combobox:

<ComboBox Grid.Row="3" Grid.Column="1" FontWeight="Bold" FontSize="28" VerticalAlignment="Center" VerticalContentAlignment="Center" Padding="10,0,0,0" SelectedItem="{Binding Language, UpdateSourceTrigger=PropertyChanged}" ItemsSource="{Binding Languages, UpdateSourceTrigger=PropertyChanged}" Margin="10,0,0,0"> <ComboBox.ItemContainerStyle> <Style TargetType="{x:Type ComboBoxItem}"> <Setter Property="FontSize" Value="28" /> </Style> </ComboBox.ItemContainerStyle> </ComboBox>

My problem is, that the combobox does not automatically fit the whole height of grid as you can see here:

In contrast, the TextBox always fit the whole size of grid. How can I customize, that ComboBox auto fit to grid size?

I am using the thememanager with following code:

public partial class MainWindow : XamRibbonWindow
    {
        public MainWindow()
        {
            InitializeComponent();
            ThemeManager.ApplicationTheme = new Office2013Theme();
        }
    }

When I comment out the thememanager, then it works as I wish.