diff --git a/Main/Source/ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/CollectionEditors/Themes/Generic.xaml b/Main/Source/ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/CollectionEditors/Themes/Generic.xaml
index c44a3f26..4ce60aaf 100644
--- a/Main/Source/ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/CollectionEditors/Themes/Generic.xaml
+++ b/Main/Source/ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/CollectionEditors/Themes/Generic.xaml
@@ -198,7 +198,7 @@
                             <Border BorderThickness="1" Background="{StaticResource PopupBackgroundBrush}" BorderBrush="{StaticResource PopupDarkBorderBrush}">
                                 <Grid>
                                     <TextBox x:Name="PART_TextBox" AcceptsReturn="true" TextWrapping="NoWrap" Padding="{TemplateBinding Padding}" VerticalScrollBarVisibility="Auto" HorizontalScrollBarVisibility="Auto"
-                                                 Width="{Binding Path=ActualWidth, ElementName=Root}" Height="150" 
+                                                 Width="200" Height="150" 
                                                  Text="{Binding Text, RelativeSource={RelativeSource TemplatedParent}}"
                                              Margin="3">
                                     </TextBox>