diff --git a/src/HexManiac.WPF/Controls/TabView.xaml b/src/HexManiac.WPF/Controls/TabView.xaml
index 074946c5..d93b0b90 100644
--- a/src/HexManiac.WPF/Controls/TabView.xaml
+++ b/src/HexManiac.WPF/Controls/TabView.xaml
@@ -402,8 +402,12 @@
                            <DataTemplate>
                               <StackPanel>
                                  <TextBlock Text="{Binding Label}" Margin="2,0"/>
-                                 <TextBox Margin="5" Text="{Binding Content, UpdateSourceTrigger=PropertyChanged}"
+                                 <Grid Margin="5">
+                                    <TextBox  Text="{Binding Content, UpdateSourceTrigger=PropertyChanged}"
                                           AcceptsReturn="True" FontFamily="Consolas" SelectionChanged="CodeToolContentsSelectionChanged"/>
+                                    <TextBlock Visibility="{Binding IsOpen, ElementName=CodeContentsPopup, Converter={StaticResource BoolToVisibility}}"
+                                          HorizontalAlignment="Left" VerticalAlignment="Top" IsHitTestVisible="False" FontFamily="Consolas" FontWeight="Bold"/>
+                                 </Grid>
                               </StackPanel>
                            </DataTemplate>
                         </ItemsControl.ItemTemplate>
diff --git a/src/HexManiac.WPF/Controls/TabView.xaml.cs b/src/HexManiac.WPF/Controls/TabView.xaml.cs
index 55cc0875..25d7e1f1 100644
--- a/src/HexManiac.WPF/Controls/TabView.xaml.cs
+++ b/src/HexManiac.WPF/Controls/TabView.xaml.cs
@@ -278,6 +278,25 @@ namespace HavenSoft.HexManiac.WPF.Controls {
          }
 
          CodeContentsPopup.IsOpen = true;
+         // var selectedLine = textbox.Text.Split(Environment.NewLine)[linesBeforeSelection];
+         // Annotate(textbox, textbox.SelectionStart, selectedLine.Split(' ')[0], Brush(nameof(Theme.Accent)));
+      }
+
+      private void Annotate(TextBox box, int index, string annotation, SolidColorBrush brush) {
+         var grid = box.Parent as Grid;
+         if (grid == null) return;
+         if (grid.Children.Count != 2) return;
+         var annotationBlock = grid.Children[1] as TextBlock;
+         if (annotationBlock == null) return;
+
+         var linesBeforeSelection = box.Text.Substring(0, index).Split(Environment.NewLine).Length - 1;
+         var totalLines = box.Text.Split(Environment.NewLine).Length;
+         var lineHeight = box.ExtentHeight / totalLines;
+         var verticalStart = lineHeight * linesBeforeSelection;
+
+         annotationBlock.Text = annotation;
+         annotationBlock.Margin = new Thickness(3, verticalStart + 1, 0, 0);
+         annotationBlock.Foreground = brush;
       }
 
       private void HeaderMouseDown(object sender, MouseButtonEventArgs e) {