diff --git a/src/Ursa.Themes.Semi/Controls/ControlClassesInput.axaml b/src/Ursa.Themes.Semi/Controls/ControlClassesInput.axaml
index b616c6e..b0a65a1 100644
--- a/src/Ursa.Themes.Semi/Controls/ControlClassesInput.axaml
+++ b/src/Ursa.Themes.Semi/Controls/ControlClassesInput.axaml
@@ -10,5 +10,12 @@
                 <u:TagInput HorizontalAlignment="Stretch" AllowDuplicates="False" Tags="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TargetClasses, Mode=TwoWay}" />
             </ControlTemplate>
         </Setter>
+        <Setter Property="ContextFlyout">
+            <MenuFlyout>
+                <MenuItem Header="Undo" Command="{Binding $parent[u:ControlClassesInput].UnDo}" />
+                <MenuItem Header="Redo" Command="{Binding $parent[u:ControlClassesInput].Redo}" />
+                <MenuItem Header="Clear" Command="{Binding $parent[u:ControlClassesInput].Clear}" />
+            </MenuFlyout>
+        </Setter>
     </ControlTheme>
 </ResourceDictionary>
diff --git a/src/Ursa/Controls/ControlClassesInput/ControlClassesInput.cs b/src/Ursa/Controls/ControlClassesInput/ControlClassesInput.cs
index 9a54bbb..2681256 100644
--- a/src/Ursa/Controls/ControlClassesInput/ControlClassesInput.cs
+++ b/src/Ursa/Controls/ControlClassesInput/ControlClassesInput.cs
@@ -74,13 +74,13 @@ public class ControlClassesInput: TemplatedControl
         var newValue = args.NewValue.Value;
         if (newValue is null)
         {
-            SaveHistory(new List<string>());
+            SaveHistory(new List<string>(), true);
             return;
         }
         else
         {
             var classes = newValue.Where(a => !string.IsNullOrWhiteSpace(a)).Distinct().ToList();
-            SaveHistory(classes);
+            SaveHistory(classes, true);
             if (newValue is INotifyCollectionChanged incc)
             {
                 incc.CollectionChanged+=InccOnCollectionChanged;
@@ -91,20 +91,20 @@ public class ControlClassesInput: TemplatedControl
 
     private void InccOnCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
     {
-        SaveHistory(TargetClasses?.ToList() ?? new List<string>());
+        SaveHistory(TargetClasses?.ToList() ?? new List<string>(), true);
     }
 
-    private void SaveHistory(List<string> strings)
+    private void SaveHistory(List<string> strings, bool fromInput)
     {
         _history.AddLast(strings);
         if (_history.Count > CountOfHistoricalRecord)
         {
             _history.RemoveFirst();
         }
-        SetClassesToTarget();
+        SetClassesToTarget(fromInput);
     }
 
-    private void SetClassesToTarget()
+    private void SetClassesToTarget(bool fromInput)
     {
         List<string> strings;
         if (_history.Count == 0)
@@ -115,6 +115,11 @@ public class ControlClassesInput: TemplatedControl
         {
             strings = _history.Last.Value;
         }
+
+        if (!fromInput)
+        {
+            SetCurrentValue(TargetClassesProperty, new ObservableCollection<string>(strings));
+        }
         if (Target is not null)
         {
             Target.Classes.Replace(strings);
@@ -130,8 +135,8 @@ public class ControlClassesInput: TemplatedControl
         var node = _history.Last;
         _history.RemoveLast();
         _undoHistory.AddFirst(node);
-        SetCurrentValue(TargetClassesProperty, new AvaloniaList<string>(node.Value));
-        SetClassesToTarget();
+        SetCurrentValue(TargetClassesProperty, new ObservableCollection<string>(node.Value));
+        SetClassesToTarget(false);
     }
 
     public void Redo()
@@ -139,12 +144,12 @@ public class ControlClassesInput: TemplatedControl
         var node = _undoHistory.First;
         _undoHistory.RemoveFirst();
         _history.AddLast(node);
-        SetCurrentValue(TargetClassesProperty, new AvaloniaList<string>(node.Value));
-        SetClassesToTarget();
+        SetCurrentValue(TargetClassesProperty, new ObservableCollection<string>(node.Value));
+        SetClassesToTarget(false);
     }
 
     public void Clear()
     {
-        SaveHistory(new List<string>());
+        SaveHistory(new List<string>(), false);
     }
 }
\ No newline at end of file