diff --git a/tests/Fluent.UITests/ControlTests/ComboBoxTests.cs b/tests/Fluent.UITests/ControlTests/ComboBoxTests.cs
new file mode 100644
index 0000000..166a0dc
--- /dev/null
+++ b/tests/Fluent.UITests/ControlTests/ComboBoxTests.cs
@@ -0,0 +1,460 @@
+using Fluent.UITests.TestUtilities;
+using FluentAssertions.Execution;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Controls.Primitives;
+using System.Windows.Documents;
+using System.Windows.Input;
+using System.Windows.Media;
+using System.Windows.Shapes;
+using Xunit.Abstractions;
+
+namespace Fluent.UITests.ControlTests
+{
+    public class ComboBoxTests: BaseControlTests
+    {
+        private ITestOutputHelper _outputHelper;
+
+        public ComboBoxTests(ITestOutputHelper outputHelper)
+        {
+            _outputHelper = outputHelper;
+            SetupTestComboBox();
+            TestComboBox.Should().NotBeNull();
+        }
+
+        #region Default Tests
+
+        [WpfFact]
+        public void ComboBox_InitialState_Test()
+        {
+            TestWindow.Show();
+            var selectedItem = TestComboBox.SelectedItem;
+            Assert.Null(selectedItem);
+        }
+
+        [WpfTheory]
+        [MemberData(nameof(ColorModes_TestData))]
+        public void ComboBox_Initialization_Test(ColorMode colorMode)
+        {
+            SetColorMode(TestWindow, colorMode);
+            TestWindow.Show();
+            ResourceDictionary rd = GetTestDataDictionary(colorMode, "");
+            VerifyControlProperties(TestComboBox, rd);
+        }
+
+        [WpfTheory]
+        [MemberData(nameof(ColorModes_TestData))]
+        public void ComboBox_HasItemsFalse_Test(ColorMode colorMode)
+        {
+            SetColorMode(TestWindow, colorMode);
+            TestWindow.Show();
+            TestComboBox.Items.Clear();
+            ResourceDictionary rd = GetTestDataDictionary(colorMode, "HasItemsFalse");
+            VerifyControlProperties(TestComboBox, rd);
+        }
+
+        [WpfTheory]
+        [MemberData(nameof(ColorModes_TestData))]
+        public void ComboBox_PopupAllowsTransparencyFalse_Test(ColorMode colorMode)
+        {
+            SetColorMode(TestWindow, colorMode);
+            TestWindow.Show();
+            Popup? popup=TestComboBox.Template.FindName("PART_Popup", TestComboBox) as Popup;
+            popup.Should().NotBeNull();
+            popup.AllowsTransparency = false;
+            ResourceDictionary rd = GetTestDataDictionary(colorMode, "AllowsTransparencyFalse");
+            VerifyControlProperties(TestComboBox, rd);
+        }
+
+        //[WpfTheory]
+        //[MemberData(nameof(ColorModes_TestData))]
+        //public void ComboBox_IsEditableTrue_Test(ColorMode colorMode)
+        //{
+        //    SetColorMode(TestWindow, colorMode);
+        //    TestWindow.Show();
+        //    TestComboBox.IsEditable = true;
+        //    ResourceDictionary rd = GetTestDataDictionary(colorMode, "IsEditable");
+        //    VerifyControlProperties(TestComboBox, rd);
+        //}
+
+        [WpfTheory]
+        [MemberData(nameof(ColorModes_TestData))]
+        public void ComboBox_Disabled_Test(ColorMode colorMode)
+        {
+            SetColorMode(TestWindow, colorMode);
+            TestWindow.Show();
+            TestComboBox.IsEnabled = false;
+            ResourceDictionary rd = GetTestDataDictionary(colorMode, "Disabled");
+            VerifyControlProperties(TestComboBox, rd);
+        }
+
+        [WpfTheory]
+        [MemberData(nameof(ColorModes_TestData))]
+        public void ComboBoxItem_Initialization_Test(ColorMode colorMode)
+        {
+            SetColorMode(TestWindow, colorMode);
+            TestWindow.Show();
+            TestComboBox.SelectedIndex = 1;
+            ResourceDictionary rd = GetTestDataDictionary(colorMode, "");
+            VerifyControlProperties(TestComboBox, rd);
+        }
+        #endregion
+
+        #region Custom Tests
+        [WpfTheory]
+        [MemberData(nameof(ColorModes_TestData))]
+        public void ComboBox_CustomSolidColorBrush_Test(ColorMode colorMode)
+        {
+            SetColorMode(TestWindow, colorMode);
+            TestWindow.Show();
+            SetSolidColorBrushProperties();
+            ResourceDictionary rd = GetTestDataDictionary(colorMode, "CustomSolidBrush");
+            VerifyControlProperties(TestComboBox, rd);
+        }
+
+        [WpfTheory]
+        [MemberData(nameof(ColorModes_TestData))]
+        public void ComboBox_Custom_Test(ColorMode colorMode)
+        {
+            SetColorMode(TestWindow, colorMode);
+            TestWindow.Show();
+            SetCustomizedProperties();
+            ResourceDictionary rd = GetTestDataDictionary(colorMode, "Custom");
+            VerifyControlProperties(TestComboBox, rd);
+        }
+        #endregion
+
+        #region Override Methods
+
+        public override List<FrameworkElement> GetStyleParts(Control element)
+        {
+            List<FrameworkElement> templateParts = [element];
+
+            Border? contentBorder = element.Template.FindName("ContentBorder", element) as Border;
+            contentBorder.Should().NotBeNull();
+
+            templateParts.Add(contentBorder);
+
+            TextBlock? chevronIcon = element.Template.FindName("ChevronIcon", element) as TextBlock;
+            chevronIcon.Should().NotBeNull();
+
+            templateParts.Add(chevronIcon);
+
+            ToggleButton? toggleButton = element.Template.FindName("ToggleButton", element) as ToggleButton;
+            toggleButton.Should().NotBeNull();
+
+            templateParts.Add(toggleButton);
+
+            TextBox? editableTextBox = element.Template.FindName("PART_EditableTextBox", element) as TextBox;
+            editableTextBox.Should().NotBeNull();
+
+            templateParts.Add(editableTextBox);
+
+            Popup? popup = element.Template.FindName("PART_Popup", element) as Popup;
+            popup.Should().NotBeNull();
+
+            templateParts.Add(popup);
+
+            Border? dropDownBorder = element.Template.FindName("DropDownBorder", element) as Border;
+            dropDownBorder.Should().NotBeNull();
+
+            templateParts.Add(dropDownBorder);
+
+            Grid? borderGrid = dropDownBorder.Child as Grid;
+            borderGrid.Should().NotBeNull();
+            UIElementCollection gridChildren = borderGrid.Children;
+            ScrollViewer? scrollViewer = gridChildren.OfType<ScrollViewer>().FirstOrDefault();
+            scrollViewer.Should().NotBeNull();
+            templateParts.Add(scrollViewer);
+
+            Border? accentBorder = element.Template.FindName("AccentBorder", element) as Border;
+            accentBorder.Should().NotBeNull();
+
+            templateParts.Add(accentBorder);
+
+            ContentPresenter? contentPresenter = element.Template.FindName("PART_ContentPresenter", element) as ContentPresenter;
+            contentPresenter.Should().NotBeNull();
+
+            templateParts.Add(contentPresenter);
+
+            return templateParts;
+        }
+        public override void VerifyControlProperties(FrameworkElement element, ResourceDictionary expectedProperties)
+        {
+            if (element is not ComboBox comboBox) return;
+
+            List<FrameworkElement> parts = GetStyleParts(comboBox);
+
+            ComboBox part_ComboBox = (ComboBox)parts[0];
+            Border? part_ContentBorder = parts[1] as Border;
+            TextBlock? part_Textblock = parts[2] as TextBlock;
+            ToggleButton? part_ToggleButton = parts[3] as ToggleButton;
+            TextBox? part_EditableTextBox = parts[4] as TextBox;
+            Popup? part_Popup = parts[5] as Popup;
+            Border? part_DropDownBorder = parts[6] as Border;
+            ScrollViewer? part_scrollViewer = parts[7] as ScrollViewer;
+            Border? part_AccentBorder = parts[8] as Border;
+            ContentPresenter? part_ContentPresenter = parts[9] as ContentPresenter;
+
+            using (new AssertionScope())
+            {
+                //validate ComboBox properties
+                VerifyComboBoxProperties(part_ComboBox, expectedProperties);
+                //validate ContentBorder properties
+                VerifyContentBorderProperties(part_ContentBorder, expectedProperties);
+                //validate Textblock properties
+                VerifyTextBlockProperties(part_Textblock, expectedProperties);
+                //validate ToggleButton properties
+                VerifyToggleButtonProperties(part_ToggleButton, expectedProperties);
+                //validate Textbox properties
+                VerifyTextBoxProperties(part_EditableTextBox, expectedProperties);
+                //validate popup properties
+                VerifyPopupProperties(part_Popup, expectedProperties);
+                //validate DropDownBorder properties
+                VerifyDropDownBorderProperties(part_DropDownBorder, expectedProperties);
+                //validate ScrollViewer properties
+                VerifyScrollViewerProperties(part_scrollViewer, expectedProperties);
+                //validate AccentBorder properties
+                VerifyAccentBorderProperties(part_AccentBorder, expectedProperties);
+                //validate ContentBorder properties
+                VerifyContentPresenterProperties(part_ContentPresenter, expectedProperties);
+                //validate ComboBoxItem properties
+                //if (part_ComboBox.SelectedItem!=null)
+                //{
+                //    ComboBoxItem? part_ComboBoxItem = part_ComboBox.SelectedItem as ComboBoxItem;
+                //    VerifyComboBoxItemProperties(part_ComboBoxItem, expectedProperties);
+                //    Control comboBoxItem = part_ComboBox;
+                //    comboBoxItem.Should().NotBeNull();
+                //    Border? ComboBoxItem_contentBorder = comboBoxItem.Template.FindName("ContentBorder", comboBoxItem) as Border;
+                //    VerifyComboBoxItemContentBorderProperties(ComboBoxItem_contentBorder, expectedProperties);
+                //    ContentPresenter? ComboBoxItem_contentPresenter = comboBoxItem.Template.FindName("PART_ContentPresenter", element) as ContentPresenter;
+                //    ComboBoxItem_contentPresenter.Should().NotBeNull();
+                //    VerifyComboBoxItemContentPresenterProperties(ComboBoxItem_contentPresenter, expectedProperties);
+                //}                
+            }
+        }
+        #endregion
+
+        #region Private Methods
+        private void SetupTestComboBox()
+        {
+            TestComboBox = new ComboBox();         
+            TestComboBox.Items.Add(new ComboBoxItem { Content = "Item 1" });
+            TestComboBox.Items.Add(new ComboBoxItem { Content = "Item 2" });
+            TestComboBox.Items.Add(new ComboBoxItem { Content = "Item 3" });
+            AddControlToView(TestWindow, TestComboBox);  
+        }
+
+        private static void VerifyComboBoxProperties(ComboBox? part_ComboBox, ResourceDictionary expectedProperties)
+        {
+            part_ComboBox.Should().NotBeNull();
+            BrushComparer.Equal(part_ComboBox.Background, (Brush)expectedProperties["ComboBox_Background"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_ComboBox.Background, (Brush)expectedProperties["ComboBox_Background"]))
+            {
+                Console.WriteLine("part_ComboBox.Background does not match expected value");
+                BrushComparer.LogBrushDifference(part_ComboBox.Background, (Brush)expectedProperties["ComboBox_Background"]);
+            }
+            BrushComparer.Equal(part_ComboBox.Foreground, (Brush)expectedProperties["ComboBox_Foreground"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_ComboBox.Foreground, (Brush)expectedProperties["ComboBox_Foreground"]))
+            {
+                Console.WriteLine("part_ComboBox.Foreground does not match expected value");
+                BrushComparer.LogBrushDifference(part_ComboBox.Foreground, (Brush)expectedProperties["ComboBox_Foreground"]);
+            }
+            //BrushComparer.Equal(part_ComboBox.BorderBrush, (Brush)expectedProperties["ComboBox_BorderBrush"]).Should().BeTrue();
+            //if (!BrushComparer.Equal(part_ComboBox.BorderBrush, (Brush)expectedProperties["ComboBox_BorderBrush"]))
+            //{
+            //    Console.WriteLine("part_ComboBox.BorderBrush does not match expected value");
+            //    BrushComparer.LogBrushDifference(part_ComboBox.BorderBrush, (Brush)expectedProperties["ComboBox_BorderBrush"]);
+            //}
+            part_ComboBox.Padding.Should().Be(expectedProperties["ComboBox_Padding"]);
+            part_ComboBox.BorderThickness.Should().Be(expectedProperties["ComboBox_BorderThickness"]);
+            part_ComboBox.MinWidth.Should().Be((Double)expectedProperties["ComboBox_MinWidth"]);
+            //part_ComboBox.MinHeight.Should().Be((Double)expectedProperties["ComboBox_MinHeight"]);
+            part_ComboBox.HorizontalAlignment.Should().Be((HorizontalAlignment?)expectedProperties["ComboBox_HorizontalAlignment"]);
+            part_ComboBox.VerticalAlignment.Should().Be((VerticalAlignment?)expectedProperties["ComboBox_VerticalAlignment"]);
+            part_ComboBox.HorizontalContentAlignment.Should().Be((HorizontalAlignment?)expectedProperties["ComboBox_HorizontalContentAlignment"]);
+            part_ComboBox.VerticalContentAlignment.Should().Be((VerticalAlignment?)expectedProperties["ComboBox_VerticalContentAlignment"]);
+         
+        }
+        private static void VerifyContentBorderProperties(Border? part_ContentBorder, ResourceDictionary expectedProperties)
+        {
+            part_ContentBorder.Should().NotBeNull();         
+            part_ContentBorder.BorderThickness.Should().Be(expectedProperties["ContentBorder_BorderThickness"]);
+            part_ContentBorder.CornerRadius.Should().Be(expectedProperties["ContentBorder__CornerRadius"]);           
+        }
+        private static void VerifyTextBlockProperties(TextBlock? part_Textblock, ResourceDictionary expectedProperties)
+        {
+            part_Textblock.Should().NotBeNull();
+            BrushComparer.Equal(part_Textblock.Foreground, (Brush)expectedProperties["Textblock_Foreground"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_Textblock.Foreground, (Brush)expectedProperties["Textblock_Foreground"]))
+            {
+                Console.WriteLine("part_Textblock.Foreground does not match expected value");
+                BrushComparer.LogBrushDifference(part_Textblock.Foreground, (Brush)expectedProperties["Textblock_Foreground"]);
+            }
+        }
+        private static void VerifyToggleButtonProperties(ToggleButton? part_ToggleButton, ResourceDictionary expectedProperties)
+        {
+            part_ToggleButton.Should().NotBeNull();
+            BrushComparer.Equal(part_ToggleButton.Background, (Brush)expectedProperties["ToggleButton_Background"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_ToggleButton.Background, (Brush)expectedProperties["ToggleButton_Background"]))
+            {
+                Console.WriteLine("part_ToggleButton.Background does not match expected value");
+                BrushComparer.LogBrushDifference(part_ToggleButton.Background, (Brush)expectedProperties["ToggleButton_Background"]);
+            }
+            BrushComparer.Equal(part_ToggleButton.Foreground, (Brush)expectedProperties["ToggleButton_Foreground"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_ToggleButton.Foreground, (Brush)expectedProperties["ToggleButton_Foreground"]))
+            {
+                Console.WriteLine("part_ToggleButton.Foreground does not match expected value");
+                BrushComparer.LogBrushDifference(part_ToggleButton.Foreground, (Brush)expectedProperties["ToggleButton_Foreground"]);
+            }
+            BrushComparer.Equal(part_ToggleButton.BorderBrush, (Brush)expectedProperties["ToggleButton_BorderBrush"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_ToggleButton.BorderBrush, (Brush)expectedProperties["ToggleButton_BorderBrush"]))
+            {
+                Console.WriteLine("part_ToggleButton.BorderBrush does not match expected value");
+                BrushComparer.LogBrushDifference(part_ToggleButton.BorderBrush, (Brush)expectedProperties["ToggleButton_BorderBrush"]);
+            }
+            part_ToggleButton.HorizontalAlignment.Should().Be((HorizontalAlignment?)expectedProperties["ToggleButton_HorizontalAlignment"]);
+            part_ToggleButton.VerticalAlignment.Should().Be((VerticalAlignment?)expectedProperties["ToggleButton_VerticalAlignment"]);
+            part_ToggleButton.BorderThickness.Should().Be(expectedProperties["ToggleButton_BorderThickness"]);
+
+            Border? part_ToggleButtonBorder = part_ToggleButton.Template.FindName("ContentBorder", part_ToggleButton) as Border;
+            part_ToggleButtonBorder.Should().NotBeNull();
+            part_ToggleButtonBorder.CornerRadius.Should().Be(expectedProperties["ToggleButton_ContentBorder_CornerRadius"]);
+            part_ToggleButtonBorder.BorderThickness.Should().Be(expectedProperties["ToggleButton_ContentBorder_BorderThickness"]);
+            BrushComparer.Equal(part_ToggleButtonBorder.Background, (Brush)expectedProperties["ToggleButton_ContentBorder__Background"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_ToggleButtonBorder.Background, (Brush)expectedProperties["ToggleButton_ContentBorder__Background"]))
+            {
+                Console.WriteLine("part_ToggleButtonBorder.Background does not match expected value");
+                BrushComparer.LogBrushDifference(part_ToggleButtonBorder.Background, (Brush)expectedProperties["ToggleButton_ContentBorder__Background"]);
+            }
+            BrushComparer.Equal(part_ToggleButtonBorder.BorderBrush, (Brush)expectedProperties["ToggleButton_ContentBorder__BorderBrush"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_ToggleButtonBorder.BorderBrush, (Brush)expectedProperties["ToggleButton_ContentBorder__BorderBrush"]))
+            {
+                Console.WriteLine("part_ToggleButtonBorder.BorderBrush does not match expected value");
+                BrushComparer.LogBrushDifference(part_ToggleButtonBorder.BorderBrush, (Brush)expectedProperties["ToggleButton_ContentBorder__BorderBrush"]);
+            }
+
+            ContentPresenter? part_ToggleButtonContentPresenter = part_ToggleButton.Template.FindName("PART_ContentHost", part_ToggleButton) as ContentPresenter;
+            part_ToggleButtonContentPresenter.Should().NotBeNull();
+        }
+        private static void VerifyTextBoxProperties(TextBox? part_EditableTextBox, ResourceDictionary expectedProperties)
+        {
+            part_EditableTextBox.Should().NotBeNull();
+            BrushComparer.Equal(part_EditableTextBox.Foreground, (Brush)expectedProperties["Textbox_Foreground"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_EditableTextBox.Foreground, (Brush)expectedProperties["Textbox_Foreground"]))
+            {
+                Console.WriteLine("part_EditableTextBox.Foreground does not match expected value");
+                BrushComparer.LogBrushDifference(part_EditableTextBox.Foreground, (Brush)expectedProperties["Textbox_Foreground"]);
+            }
+            if (!BrushComparer.Equal(part_EditableTextBox.Background, (Brush)expectedProperties["Textbox_Background"]))
+            {
+                Console.WriteLine("part_EditableTextBox.Background does not match expected value");
+                BrushComparer.LogBrushDifference(part_EditableTextBox.Background, (Brush)expectedProperties["Textbox_Background"]);
+            }
+            if (!BrushComparer.Equal(part_EditableTextBox.CaretBrush, (Brush)expectedProperties["Textbox_CaretBrush"]))
+            {
+                Console.WriteLine("part_EditableTextBox.CaretBrush does not match expected value");
+                BrushComparer.LogBrushDifference(part_EditableTextBox.CaretBrush, (Brush)expectedProperties["Textbox_CaretBrush"]);
+            }
+            part_EditableTextBox.HorizontalAlignment.Should().Be((HorizontalAlignment?)expectedProperties["Textbox_HorizontalAlignment"]);
+            part_EditableTextBox.VerticalAlignment.Should().Be((VerticalAlignment?)expectedProperties["Textbox_VerticalAlignment"]);
+            part_EditableTextBox.Padding.Should().Be(expectedProperties["Textbox_Padding"]);
+            part_EditableTextBox.Margin.Should().Be(expectedProperties["Textbox_Margin"]);
+            part_EditableTextBox.Visibility.Should().Be((Visibility)expectedProperties["Textbox_Visibility"]);
+            //part_EditableTextBox.FontSize.Should().Be((Double)expectedProperties["Textbox_FontSize"]);
+            part_EditableTextBox.Cursor.Should().Be((Cursor)expectedProperties["Textbox_Cursor"]);
+          
+        }
+        private static void VerifyPopupProperties(Popup? part_Popup, ResourceDictionary expectedProperties)
+        {
+            part_Popup.Should().NotBeNull();
+            part_Popup.VerticalAlignment.Should().Be((VerticalAlignment?)expectedProperties["Popup_VerticalAlignment"]);
+            //part_Popup.AllowsTransparency.Should().Be((Boolean)expectedProperties["Popup_AllowsTransparency"]);
+            part_Popup.Focusable.Should().Be((Boolean)expectedProperties["Popup_Focusable"]);
+            part_Popup.Placement.Should().Be((PlacementMode)expectedProperties["Popup_Placement"]);
+            part_Popup.PopupAnimation.Should().Be((PopupAnimation)expectedProperties["Popup_Animation"]);
+            part_Popup.VerticalOffset.Should().Be((Double)expectedProperties["Popup_VerticalOffset"]);
+        }
+        private static void VerifyDropDownBorderProperties(Border? part_DropDownBorder, ResourceDictionary expectedProperties)
+        {
+            part_DropDownBorder.Should().NotBeNull();
+            BrushComparer.Equal(part_DropDownBorder.Background, (Brush)expectedProperties["DropDownBorder_Background"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_DropDownBorder.Background, (Brush)expectedProperties["DropDownBorder_Background"]))
+            {
+                Console.WriteLine("part_DropDownBorder.Background does not match expected value");
+                BrushComparer.LogBrushDifference(part_DropDownBorder.Background, (Brush)expectedProperties["DropDownBorder_Background"]);
+            }
+            BrushComparer.Equal(part_DropDownBorder.BorderBrush, (Brush)expectedProperties["DropDownBorder_BorderBrush"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_DropDownBorder.BorderBrush, (Brush)expectedProperties["DropDownBorder_BorderBrush"]))
+            {
+                Console.WriteLine("part_DropDownBorder.BorderBrush does not match expected value");
+                BrushComparer.LogBrushDifference(part_DropDownBorder.BorderBrush, (Brush)expectedProperties["DropDownBorder_BorderBrush"]);
+            }
+            part_DropDownBorder.Padding.Should().Be(expectedProperties["DropDownBorder_Padding"]);
+            part_DropDownBorder.BorderThickness.Should().Be(expectedProperties["DropDownBorder_BorderThickness"]);
+            part_DropDownBorder.CornerRadius.Should().Be(expectedProperties["DropDownBorder_CornerRadius"]);
+            part_DropDownBorder.MinHeight.Should().Be((Double)expectedProperties["DropDownBorder_Height"]);
+        }
+        private static void VerifyScrollViewerProperties(ScrollViewer? part_scrollViewer, ResourceDictionary expectedProperties)
+        {
+            part_scrollViewer.Should().NotBeNull();
+            BrushComparer.Equal(part_scrollViewer.Foreground, (Brush)expectedProperties["ScrollViewer_Foreground"]).Should().BeTrue();
+            if (!BrushComparer.Equal(part_scrollViewer.Foreground, (Brush)expectedProperties["ScrollViewer_Foreground"]))
+            {
+                Console.WriteLine("part_scrollViewer.Foreground does not match expected value");
+                BrushComparer.LogBrushDifference(part_scrollViewer.Foreground, (Brush)expectedProperties["ScrollViewer_Foreground"]);
+            }
+            part_scrollViewer.HorizontalScrollBarVisibility.Should().Be((ScrollBarVisibility)expectedProperties["ScrollViewer_HorizontalScrollBarVisibility"]);
+            part_scrollViewer.VerticalScrollBarVisibility.Should().Be((ScrollBarVisibility)expectedProperties["ScrollViewer_VerticalScrollBarVisibility"]);
+            part_scrollViewer.IsDeferredScrollingEnabled.Should().Be((Boolean)expectedProperties["ScrollViewer_IsDeferredScrollingEnabled"]);
+        }
+        private static void VerifyAccentBorderProperties(Border? part_AccentBorder, ResourceDictionary expectedProperties)
+        {
+            part_AccentBorder.Should().NotBeNull();
+            part_AccentBorder.HorizontalAlignment.Should().Be((HorizontalAlignment?)expectedProperties["AccentBorder_HorizontalAlignment"]);
+            part_AccentBorder.VerticalAlignment.Should().Be((VerticalAlignment?)expectedProperties["AccentBorder_VerticalAlignment"]);
+            part_AccentBorder.CornerRadius.Should().Be(expectedProperties["AccentBorder_CornerRadius"]);
+            part_AccentBorder.Visibility.Should().Be((Visibility)expectedProperties["AccentBorder_Visibility"]);
+        }
+        private static void VerifyContentPresenterProperties(ContentPresenter? part_ContentPresenter, ResourceDictionary expectedProperties)
+        {
+            part_ContentPresenter.Should().NotBeNull();
+            BrushComparer.Equal(TextElement.GetForeground(part_ContentPresenter), (Brush)expectedProperties["ContentPresenter_Foreground"]).Should().BeTrue();
+            if (!BrushComparer.Equal(TextElement.GetForeground(part_ContentPresenter), (Brush)expectedProperties["ContentPresenter_Foreground"]))
+            {
+                Console.WriteLine("part_ContentPresenter.Foreground does not match expected value");
+                BrushComparer.LogBrushDifference(TextElement.GetForeground(part_ContentPresenter), (Brush)expectedProperties["ContentPresenter_Foreground"]);
+            }
+            part_ContentPresenter.HorizontalAlignment.Should().Be((HorizontalAlignment?)expectedProperties["ContentPresenter_HorizontalAlignment"]);
+            part_ContentPresenter.VerticalAlignment.Should().Be((VerticalAlignment?)expectedProperties["ContentPresenter_VerticalAlignment"]);
+                  }
+        private void SetSolidColorBrushProperties()
+        {
+            TestComboBox.Background = new SolidColorBrush((Color)ColorConverter.ConvertFromString("Aqua"));
+            TestComboBox.Foreground = new SolidColorBrush((Color)ColorConverter.ConvertFromString("Maroon"));
+            // TestComboBox.BorderBrush = new SolidColorBrush((Color)ColorConverter.ConvertFromString("Green"));
+        }
+        private void SetCustomizedProperties()
+        {
+            TestComboBox.BorderThickness = new Thickness(10);
+            TestComboBox.Padding = new Thickness(20, 4, 10, 10);
+            TestComboBox.MinWidth = 90;
+            TestComboBox.HorizontalAlignment = System.Windows.HorizontalAlignment.Right;
+            TestComboBox.VerticalAlignment = System.Windows.VerticalAlignment.Bottom;
+            TestComboBox.HorizontalContentAlignment = System.Windows.HorizontalAlignment.Right;
+            TestComboBox.VerticalContentAlignment = System.Windows.VerticalAlignment.Bottom;
+        }
+        #endregion
+
+        #region Private Properties
+
+        private ComboBox TestComboBox { get; set; }
+        //private ComboBox TestEmptyComboBox { get; set; }
+
+        protected override string TestDataDictionaryPath => @"/Fluent.UITests;component/ControlTests/Data/ComboBoxTests.xaml";
+        #endregion
+    }
+}
diff --git a/tests/Fluent.UITests/ControlTests/Data/ComboBoxTests.xaml b/tests/Fluent.UITests/ControlTests/Data/ComboBoxTests.xaml
new file mode 100644
index 0000000..fc73e3b
--- /dev/null
+++ b/tests/Fluent.UITests/ControlTests/Data/ComboBoxTests.xaml
@@ -0,0 +1,435 @@
+<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    xmlns:sys="clr-namespace:System;assembly=System.Runtime"
+                     xmlns:ut="clr-namespace:Fluent.UITests.TestUtilities">
+    <ResourceDictionary.MergedDictionaries>
+        <ut:TestDictionary Name="Light">
+            <ut:TestDictionary.MergedDictionaries>
+                <ut:TestDictionary Source="/Fluent.UITests;component/ResourceTests/Data/Light.Test.xaml" />
+                <ut:TestDictionary Name="Default">
+
+                    <SolidColorBrush x:Key="ComboBox_Background" Color="{StaticResource ControlFillColorDefault}" />
+                    <SolidColorBrush x:Key="ComboBox_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    <!--<SolidColorBrush x:Key="ComboBox_BorderBrush" Color="{StaticResource ControlFillColorTransparent}" />-->
+                    <Thickness x:Key="ComboBox_BorderThickness">1</Thickness>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalAlignment">Left</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalAlignment">Top</VerticalAlignment>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalContentAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalContentAlignment">Top</VerticalAlignment>
+                    <!--<sys:Double x:Key="ComboBox_MinHeight">32</sys:Double>-->
+                    <sys:Double x:Key="ComboBox_MinWidth">0</sys:Double>
+                    <Thickness x:Key="ComboBox_Padding">12,5,0,7</Thickness>
+
+
+                    <!--Content Border properties-->
+                    <!--<sys:Double x:Key="ContentBorder_MinHeight">32</sys:Double>
+                    <sys:Double x:Key="ContentBorder_MinWidth">0</sys:Double>-->
+                    <!--<SolidColorBrush x:Key="ContentBorder_BorderBrush" Color="{StaticResource ControlFillColorTransparent}" />-->
+                    <SolidColorBrush x:Key="ContentBorder_Background" Color="{StaticResource ControlFillColorDefault}" />
+                    <Thickness x:Key="ContentBorder_BorderThickness">1</Thickness>
+                    <CornerRadius x:Key="ContentBorder__CornerRadius">4,4,4,4</CornerRadius>
+                    <!--<HorizontalAlignment x:Key="ContentBorder_HorizontalAlignment">Left</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ContentBorder_VerticalAlignment">Top</VerticalAlignment>-->
+
+                    <!--content presenter properties-->
+                    <SolidColorBrush x:Key="ContentPresenter_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    <HorizontalAlignment x:Key="ContentPresenter_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ContentPresenter_VerticalAlignment">Stretch</VerticalAlignment>
+                    <!--Textblock properties-->
+                    <SolidColorBrush x:Key="Textblock_Foreground" Color="{StaticResource TextFillColorSecondary}" />
+                   
+                    <!--Toggle Button properties-->
+                    <SolidColorBrush x:Key="ToggleButton_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    <SolidColorBrush x:Key="ToggleButton_Background" Color="{StaticResource SystemControlTransparent}" />
+                    <SolidColorBrush x:Key="ToggleButton_BorderBrush" Color="{StaticResource SystemControlTransparent}" />
+                    <Thickness x:Key="ToggleButton_BorderThickness">0</Thickness>
+                    <HorizontalAlignment x:Key="ToggleButton_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ToggleButton_VerticalAlignment">Stretch</VerticalAlignment>
+
+                    <CornerRadius x:Key="ToggleButton_ContentBorder_CornerRadius">0</CornerRadius>
+                    <SolidColorBrush x:Key="ToggleButton_ContentBorder__Background" Color="{StaticResource SystemControlTransparent}" />
+                    <SolidColorBrush x:Key="ToggleButton_ContentBorder__BorderBrush" Color="{StaticResource SystemControlTransparent}" />
+                    <Thickness x:Key="ToggleButton_ContentBorder_BorderThickness">0</Thickness>
+
+
+                    <!--Textbox properties-->
+                    <HorizontalAlignment x:Key="Textbox_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <SolidColorBrush x:Key="Textbox_Foreground" Color="{StaticResource TextFillColorSecondary}" />
+                    <Visibility x:Key="Textbox_Visibility">Collapsed</Visibility>
+                    <Thickness x:Key="Textbox_Margin">0</Thickness>
+                    <Thickness x:Key="Textbox_Padding">11,5,38,6</Thickness>
+
+                    <!--not in winui-->
+                    <VerticalAlignment x:Key="Textbox_VerticalAlignment">Stretch</VerticalAlignment>
+                    <sys:Double x:Key="Textbox_Fontsize">14</sys:Double>
+                    <Cursor x:Key="Textbox_Cursor">IBeam</Cursor>
+                    <SolidColorBrush x:Key="Textbox_CaretBrush" Color="{StaticResource TextFillColorPrimary}" />
+                    <SolidColorBrush x:Key="Textbox_Background" Color="{StaticResource SystemControlTransparent}" />
+                    
+                    <!--Popup properties-->
+                    <!--not in winui-->
+                    <!--<sys:Double x:Key="Popup_MinWidth">14</sys:Double>-->
+                    <VerticalAlignment x:Key="Popup_VerticalAlignment">Center</VerticalAlignment>
+                    <!--<sys:Boolean x:Key="Popup_AllowsTransparency">True</sys:Boolean>-->
+                    <sys:Boolean x:Key="Popup_Focusable">False</sys:Boolean>
+                    <PlacementMode x:Key="Popup_Placement">Bottom</PlacementMode>
+                    <PopupAnimation x:Key="Popup_Animation">None</PopupAnimation>
+                    <sys:Double x:Key="Popup_VerticalOffset">1</sys:Double>
+
+                    <!--DropDownBorder properties-->
+                    <SolidColorBrush x:Key="DropDownBorder_Background" Color="{StaticResource AcrylicInAppFillColorDefault}" />
+                    <SolidColorBrush x:Key="DropDownBorder_BorderBrush" Color="{StaticResource SurfaceStrokeColorFlyout}" />
+                    <Thickness x:Key="DropDownBorder_Padding">0</Thickness>
+                    <Thickness x:Key="DropDownBorder_BorderThickness">1</Thickness>
+                    <CornerRadius x:Key="DropDownBorder_CornerRadius">8</CornerRadius>
+                    <sys:Double x:Key="DropDownBorder_Height">0</sys:Double>
+                    
+                    <!--ScrollViewer properties-->
+                    <ScrollBarVisibility x:Key="ScrollViewer_HorizontalScrollBarVisibility">Hidden</ScrollBarVisibility>
+                    <ScrollBarVisibility x:Key="ScrollViewer_VerticalScrollBarVisibility">Hidden</ScrollBarVisibility>
+                    <sys:Boolean x:Key="ScrollViewer_IsDeferredScrollingEnabled">False</sys:Boolean>
+                    <SolidColorBrush x:Key="ScrollViewer_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    <!--Accent Border properties-->
+                    <HorizontalAlignment x:Key="AccentBorder_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="AccentBorder_VerticalAlignment">Stretch</VerticalAlignment>
+                    <CornerRadius x:Key="AccentBorder_CornerRadius">4</CornerRadius>
+                    <Visibility x:Key="AccentBorder_Visibility">Collapsed</Visibility>
+                    
+                    <!--comboboxitem properties
+                    <SolidColorBrush x:Key="ComboBoxItem_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    <SolidColorBrush x:Key="ComboBoxItem_Background" Color="{StaticResource SubtleFillColorTransparent}" />
+                    <Thickness x:Key="ComboBoxItem_Padding">11,5,11,7</Thickness>
+                    <CornerRadius x:Key="ComboBoxItem_CornerRadius">3</CornerRadius>
+
+                    comboboxitem content border properties
+                    <CornerRadius x:Key="ComboBoxItem_ContentBorder_CornerRadius">4</CornerRadius>
+                    <Thickness x:Key="ComboBoxItem_ContentBorder_Padding">0</Thickness>
+                    <Thickness x:Key="ComboBoxItem_ContentBorder_Margin">3,2,3,0</Thickness>
+                    <VerticalAlignment x:Key="ComboBoxItem_ContentBorder_VerticalAlignment">Stretch</VerticalAlignment>-->
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="HasItemsFalse">
+                    <sys:Double x:Key="DropDownBorder_Height">32</sys:Double>
+                </ut:TestDictionary>
+                
+                <ut:TestDictionary Name="AllowsTransparencyFalse">
+                    <CornerRadius x:Key="DropDownBorder_CornerRadius">0</CornerRadius>
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="IsEditable">
+                    <Visibility x:Key="Textbox_Visibility">Visible</Visibility>
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="Disabled">
+                    <SolidColorBrush x:Key="ContentBorder_Background" Color="{StaticResource ControlFillColorDisabled}" />
+                    <SolidColorBrush x:Key="ComboBox_Foreground" Color="{StaticResource TextFillColorDisabled}" />
+                    <!--<SolidColorBrush x:Key="ContentBorder_BorderBrush" Color="{StaticResource ControlStrokeColorDefault}" />-->
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="CustomSolidBrush">
+                    <SolidColorBrush x:Key="ComboBox_Background" Color="Aqua" />
+                    <SolidColorBrush x:Key="ComboBox_Foreground" Color="Maroon" />
+                    <!--<SolidColorBrush x:Key="ComboBox_BorderBrush" Color="{StaticResource ControlFillColorTransparent}" />-->
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="Custom">
+                    <Thickness x:Key="ComboBox_BorderThickness">10</Thickness>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalAlignment">Right</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalAlignment">Bottom</VerticalAlignment>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalContentAlignment">Right</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalContentAlignment">Bottom</VerticalAlignment>
+                    <!--<sys:Double x:Key="ComboBox_MinHeight">32</sys:Double>-->
+                    <sys:Double x:Key="ComboBox_MinWidth">90</sys:Double>
+                    <Thickness x:Key="ComboBox_Padding">20,4,10,10</Thickness>
+                </ut:TestDictionary>
+
+            </ut:TestDictionary.MergedDictionaries>
+        </ut:TestDictionary>
+        <ut:TestDictionary Name="Dark">
+            <ut:TestDictionary.MergedDictionaries>
+                <ut:TestDictionary Source="/Fluent.UITests;component/ResourceTests/Data/Dark.Test.xaml" />
+                <ut:TestDictionary Name="Default">
+                    <SolidColorBrush x:Key="ComboBox_Background" Color="{StaticResource ControlFillColorDefault}" />
+                    <SolidColorBrush x:Key="ComboBox_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    <!--<SolidColorBrush x:Key="ComboBox_BorderBrush" Color="{StaticResource ControlFillColorTransparent}" />-->
+                    <Thickness x:Key="ComboBox_BorderThickness">1</Thickness>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalAlignment">Left</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalAlignment">Top</VerticalAlignment>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalContentAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalContentAlignment">Top</VerticalAlignment>
+                    <!--<sys:Double x:Key="ComboBox_MinHeight">32</sys:Double>-->
+                    <sys:Double x:Key="ComboBox_MinWidth">0</sys:Double>
+                    <Thickness x:Key="ComboBox_Padding">12,5,0,7</Thickness>
+
+                    <!--Content Border properties-->
+                    <!--<sys:Double x:Key="ContentBorder_MinHeight">32</sys:Double>
+                    <sys:Double x:Key="ContentBorder_MinWidth">0</sys:Double>-->
+                    <SolidColorBrush x:Key="ContentBorder_Background" Color="{StaticResource ControlFillColorDefault}" />
+                    <Thickness x:Key="ContentBorder_BorderThickness">1</Thickness>
+                    <CornerRadius x:Key="ContentBorder__CornerRadius">4,4,4,4</CornerRadius>
+                    <!--<HorizontalAlignment x:Key="ContentBorder_HorizontalAlignment">Left</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ContentBorder_VerticalAlignment">Top</VerticalAlignment>-->
+
+                    <!--content presenter properties-->
+                    <SolidColorBrush x:Key="ContentPresenter_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    <HorizontalAlignment x:Key="ContentPresenter_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ContentPresenter_VerticalAlignment">Stretch</VerticalAlignment>
+                    <!--Textblock properties-->
+                    <SolidColorBrush x:Key="Textblock_Foreground" Color="{StaticResource TextFillColorSecondary}" />
+
+                    <!--Toggle Button properties-->
+                    <SolidColorBrush x:Key="ToggleButton_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    <SolidColorBrush x:Key="ToggleButton_Background" Color="{StaticResource SystemControlTransparent}" />
+                    <SolidColorBrush x:Key="ToggleButton_BorderBrush" Color="{StaticResource SystemControlTransparent}" />
+                    <Thickness x:Key="ToggleButton_BorderThickness">0</Thickness>
+                    <HorizontalAlignment x:Key="ToggleButton_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ToggleButton_VerticalAlignment">Stretch</VerticalAlignment>
+
+                    <CornerRadius x:Key="ToggleButton_ContentBorder_CornerRadius">0</CornerRadius>
+                    <SolidColorBrush x:Key="ToggleButton_ContentBorder__Background" Color="{StaticResource SystemControlTransparent}" />
+                    <SolidColorBrush x:Key="ToggleButton_ContentBorder__BorderBrush" Color="{StaticResource SystemControlTransparent}" />
+                    <Thickness x:Key="ToggleButton_ContentBorder_BorderThickness">0</Thickness>
+
+
+                    <!--Textbox properties-->
+                    <HorizontalAlignment x:Key="Textbox_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <SolidColorBrush x:Key="Textbox_Foreground" Color="{StaticResource TextFillColorSecondary}" />
+                    <Visibility x:Key="Textbox_Visibility">Collapsed</Visibility>
+                    <Thickness x:Key="Textbox_Margin">0</Thickness>
+                    <Thickness x:Key="Textbox_Padding">11,5,38,6</Thickness>
+                    
+                    <!--not in winui-->
+                    <VerticalAlignment x:Key="Textbox_VerticalAlignment">Stretch</VerticalAlignment>
+                    <sys:Double x:Key="Textbox_Fontsize">14</sys:Double>
+                    <Cursor x:Key="Textbox_Cursor">IBeam</Cursor>
+                    <SolidColorBrush x:Key="Textbox_CaretBrush" Color="{StaticResource TextFillColorPrimary}" />
+                    <SolidColorBrush x:Key="Textbox_Background" Color="{StaticResource SystemControlTransparent}" />
+
+                    <!--Popup properties-->
+                    <!--not in winui-->
+                    <!--<sys:Double x:Key="Popup_MinWidth">14</sys:Double>-->
+                    <VerticalAlignment x:Key="Popup_VerticalAlignment">Center</VerticalAlignment>
+                    <!--<sys:Boolean x:Key="Popup_AllowsTransparency">True</sys:Boolean>-->
+                    <sys:Boolean x:Key="Popup_Focusable">False</sys:Boolean>
+                    <PlacementMode x:Key="Popup_Placement">Bottom</PlacementMode>
+                    <PopupAnimation x:Key="Popup_Animation">None</PopupAnimation>
+                    <sys:Double x:Key="Popup_VerticalOffset">1</sys:Double>
+
+                    <!--DropDownBorder properties-->
+                    <SolidColorBrush x:Key="DropDownBorder_Background" Color="{StaticResource AcrylicInAppFillColorDefault}" />
+                    <SolidColorBrush x:Key="DropDownBorder_BorderBrush" Color="{StaticResource SurfaceStrokeColorFlyout}" />
+                    <Thickness x:Key="DropDownBorder_Padding">0</Thickness>
+                    <Thickness x:Key="DropDownBorder_BorderThickness">1</Thickness>
+                    <CornerRadius x:Key="DropDownBorder_CornerRadius">8</CornerRadius>
+                    <sys:Double x:Key="DropDownBorder_Height">0</sys:Double>
+
+                    <!--ScrollViewer properties-->
+                    <ScrollBarVisibility x:Key="ScrollViewer_HorizontalScrollBarVisibility">Hidden</ScrollBarVisibility>
+                    <ScrollBarVisibility x:Key="ScrollViewer_VerticalScrollBarVisibility">Hidden</ScrollBarVisibility>
+                    <sys:Boolean x:Key="ScrollViewer_IsDeferredScrollingEnabled">False</sys:Boolean>
+                    <SolidColorBrush x:Key="ScrollViewer_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    
+                    <!--Accent Border properties-->
+                    <HorizontalAlignment x:Key="AccentBorder_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="AccentBorder_VerticalAlignment">Stretch</VerticalAlignment>
+                    <CornerRadius x:Key="AccentBorder_CornerRadius">4</CornerRadius>
+                    <Visibility x:Key="AccentBorder_Visibility">Collapsed</Visibility>
+
+                    <!--comboboxitem properties--><!--
+                    <SolidColorBrush x:Key="ComboBoxItem_Foreground" Color="{StaticResource TextFillColorPrimary}" />
+                    <SolidColorBrush x:Key="ComboBoxItem_Background" Color="{StaticResource SubtleFillColorTransparent}" />
+                    <Thickness x:Key="ComboBoxItem_Padding">11,5,11,7</Thickness>
+
+                    --><!--comboboxitem content border properties--><!--
+                    <CornerRadius x:Key="ComboBoxItem_ContentBorder_CornerRadius">4</CornerRadius>
+                    <Thickness x:Key="ComboBoxItem_ContentBorder_Padding">0</Thickness>
+                    <Thickness x:Key="ComboBoxItem_ContentBorder_Margin">3,2,3,0</Thickness>
+                    <VerticalAlignment x:Key="ComboBoxItem_ContentBorder_VerticalAlignment">Stretch</VerticalAlignment>-->
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="HasItemsFalse">
+                    <sys:Double x:Key="DropDownBorder_Height">32</sys:Double>
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="AllowsTransparencyFalse">
+                    <CornerRadius x:Key="DropDownBorder_CornerRadius">0</CornerRadius>
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="IsEditable">
+                    <Visibility x:Key="Textbox_Visibility">Visible</Visibility>
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="Disabled">
+                    <SolidColorBrush x:Key="ContentBorder_Background" Color="{StaticResource ControlFillColorDisabled}" />
+                    <SolidColorBrush x:Key="ComboBox_Foreground" Color="{StaticResource TextFillColorDisabled}" />
+                    <!--<SolidColorBrush x:Key="ContentBorder_BorderBrush" Color="{StaticResource ControlStrokeColorDefault}" />-->
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="CustomSolidBrush">
+                    <SolidColorBrush x:Key="ComboBox_Background" Color="Aqua" />
+                    <SolidColorBrush x:Key="ComboBox_Foreground" Color="Maroon" />
+                    <!--<SolidColorBrush x:Key="ComboBox_BorderBrush" Color="{StaticResource ControlFillColorTransparent}" />-->
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="Custom">
+                    <Thickness x:Key="ComboBox_BorderThickness">10</Thickness>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalAlignment">Right</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalAlignment">Bottom</VerticalAlignment>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalContentAlignment">Right</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalContentAlignment">Bottom</VerticalAlignment>
+                    <!--<sys:Double x:Key="ComboBox_MinHeight">32</sys:Double>-->
+                    <sys:Double x:Key="ComboBox_MinWidth">90</sys:Double>
+                    <Thickness x:Key="ComboBox_Padding">20,4,10,10</Thickness>
+                </ut:TestDictionary>
+            </ut:TestDictionary.MergedDictionaries>
+        </ut:TestDictionary>
+        <ut:TestDictionary Name="HC">
+            <ut:TestDictionary.MergedDictionaries>
+                <ut:TestDictionary Source="/Fluent.UITests;component/ResourceTests/Data/HC.Test.xaml" />
+                <ut:TestDictionary Name="Default">
+                    <!--<SolidColorBrush x:Key="ComboBox_Background" Color="{StaticResource SystemControlBackgroundAltMediumLow}" />-->
+                    <SolidColorBrush x:Key="ComboBox_Background" Color="{StaticResource SystemColorButtonFaceColor}" />
+                    <!--<SolidColorBrush x:Key="ComboBox_Foreground" Color="{StaticResource SystemControlForegroundBaseHigh}" />-->
+                    <SolidColorBrush x:Key="ComboBox_Foreground" Color="{StaticResource SystemColorButtonTextColor}" />
+                    <!--<SolidColorBrush x:Key="ComboBox_BorderBrush" Color="{StaticResource ControlFillColorTransparent}" />-->
+                    <Thickness x:Key="ComboBox_BorderThickness">1</Thickness>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalAlignment">Left</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalAlignment">Top</VerticalAlignment>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalContentAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalContentAlignment">Top</VerticalAlignment>
+                    <!--<sys:Double x:Key="ComboBox_MinHeight">32</sys:Double>-->
+                    <sys:Double x:Key="ComboBox_MinWidth">0</sys:Double>
+                    <Thickness x:Key="ComboBox_Padding">12,5,0,7</Thickness>
+
+                    <!--Content Border properties-->
+                    <!--<sys:Double x:Key="ContentBorder_MinHeight">32</sys:Double>
+                    <sys:Double x:Key="ContentBorder_MinWidth">0</sys:Double>-->
+                    <SolidColorBrush x:Key="ContentBorder_Background" Color="{StaticResource SystemColorButtonFaceColor}" />
+                    <Thickness x:Key="ContentBorder_BorderThickness">1</Thickness>
+                    <CornerRadius x:Key="ContentBorder__CornerRadius">4,4,4,4</CornerRadius>
+                    <!--<HorizontalAlignment x:Key="ContentBorder_HorizontalAlignment">Left</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ContentBorder_VerticalAlignment">Top</VerticalAlignment>-->
+
+                    <!--content presenter properties-->
+                    <SolidColorBrush x:Key="ContentPresenter_Foreground" Color="{StaticResource SystemColorButtonTextColor}" />
+                    <!--<SolidColorBrush x:Key="ContentPresenter_Foreground" Color="{StaticResource SystemControlForegroundBaseHigh}" />-->
+                    <HorizontalAlignment x:Key="ContentPresenter_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ContentPresenter_VerticalAlignment">Stretch</VerticalAlignment>
+                    <!--Textblock properties-->
+                    <SolidColorBrush x:Key="Textblock_Foreground" Color="{StaticResource TextFillColorSecondary}" />
+
+                    <!--Toggle Button properties-->
+                    <SolidColorBrush x:Key="ToggleButton_Foreground" Color="{StaticResource SystemColorButtonTextColor}" />
+                    <SolidColorBrush x:Key="ToggleButton_Background" Color="{StaticResource SystemControlTransparent}" />
+                    <SolidColorBrush x:Key="ToggleButton_BorderBrush" Color="{StaticResource SystemControlTransparent}" />
+                    <Thickness x:Key="ToggleButton_BorderThickness">0</Thickness>
+                    <HorizontalAlignment x:Key="ToggleButton_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ToggleButton_VerticalAlignment">Stretch</VerticalAlignment>
+
+                    <CornerRadius x:Key="ToggleButton_ContentBorder_CornerRadius">0</CornerRadius>
+                    <SolidColorBrush x:Key="ToggleButton_ContentBorder__Background" Color="{StaticResource SystemControlTransparent}" />
+                    <SolidColorBrush x:Key="ToggleButton_ContentBorder__BorderBrush" Color="{StaticResource SystemControlTransparent}" />
+                    <Thickness x:Key="ToggleButton_ContentBorder_BorderThickness">0</Thickness>
+
+                    <!--Textbox properties-->
+                    <HorizontalAlignment x:Key="Textbox_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <SolidColorBrush x:Key="Textbox_Foreground" Color="{StaticResource TextFillColorSecondary}" />
+                    <Visibility x:Key="Textbox_Visibility">Collapsed</Visibility>
+                    <Thickness x:Key="Textbox_Margin">0</Thickness>
+                    <Thickness x:Key="Textbox_Padding">11,5,38,6</Thickness>
+
+                    <!--not in winui-->
+                    <VerticalAlignment x:Key="Textbox_VerticalAlignment">Stretch</VerticalAlignment>
+                    <sys:Double x:Key="Textbox_Fontsize">14</sys:Double>
+                    <Cursor x:Key="Textbox_Cursor">IBeam</Cursor>
+                    <SolidColorBrush x:Key="Textbox_CaretBrush" Color="{StaticResource TextFillColorPrimary}" />
+                    <SolidColorBrush x:Key="Textbox_Background" Color="{StaticResource SystemControlTransparent}" />
+
+                    <!--Popup properties-->
+                    <!--not in winui-->
+                    <!--<sys:Double x:Key="Popup_MinWidth">14</sys:Double>-->
+                    <VerticalAlignment x:Key="Popup_VerticalAlignment">Center</VerticalAlignment>
+                    <!--<sys:Boolean x:Key="Popup_AllowsTransparency">True</sys:Boolean>-->
+                    <sys:Boolean x:Key="Popup_Focusable">False</sys:Boolean>
+                    <PlacementMode x:Key="Popup_Placement">Bottom</PlacementMode>
+                    <PopupAnimation x:Key="Popup_Animation">None</PopupAnimation>
+                    <sys:Double x:Key="Popup_VerticalOffset">1</sys:Double>
+                   
+                    <!--DropDownBorder properties-->
+                    <!--<SolidColorBrush x:Key="DropDownBorder_Background" Color="{StaticResource SystemControlBackgroundChromeMediumLow}" />-->
+                    <!--<SolidColorBrush x:Key="DropDownBorder_BorderBrush" Color="{StaticResource SystemControlForegroundChromeHigh}" />-->
+                    <!--Value is from WPF as winui key is not defined-->
+                    <SolidColorBrush x:Key="DropDownBorder_Background" Color="{StaticResource SystemColorWindowColor}" />
+                    <SolidColorBrush x:Key="DropDownBorder_BorderBrush" Color="{StaticResource SystemColorWindowTextColor}" />
+                    <Thickness x:Key="DropDownBorder_Padding">0</Thickness>
+                    <Thickness x:Key="DropDownBorder_BorderThickness">1</Thickness>
+                    <CornerRadius x:Key="DropDownBorder_CornerRadius">8</CornerRadius>
+                    <sys:Double x:Key="DropDownBorder_Height">0</sys:Double>
+
+                    <!--ScrollViewer properties-->
+                    <ScrollBarVisibility x:Key="ScrollViewer_HorizontalScrollBarVisibility">Hidden</ScrollBarVisibility>
+                    <ScrollBarVisibility x:Key="ScrollViewer_VerticalScrollBarVisibility">Hidden</ScrollBarVisibility>
+                    <sys:Boolean x:Key="ScrollViewer_IsDeferredScrollingEnabled">False</sys:Boolean>
+                    <SolidColorBrush x:Key="ScrollViewer_Foreground" Color="{StaticResource SystemColorButtonTextColor}" />
+                    <!--<SolidColorBrush x:Key="ScrollViewer_Foreground" Color="{StaticResource SystemControlForegroundBaseHigh}" />-->
+                    
+                    <!--Accent Border properties-->
+                    <HorizontalAlignment x:Key="AccentBorder_HorizontalAlignment">Stretch</HorizontalAlignment>
+                    <VerticalAlignment x:Key="AccentBorder_VerticalAlignment">Stretch</VerticalAlignment>
+                    <CornerRadius x:Key="AccentBorder_CornerRadius">4</CornerRadius>
+                    <Visibility x:Key="AccentBorder_Visibility">Collapsed</Visibility>
+
+                    <!--comboboxitem properties-->
+                    <!--<SolidColorBrush x:Key="ComboBoxItem_Foreground" Color="{StaticResource SystemControlForegroundBaseHigh}" />--><!--
+                    <SolidColorBrush x:Key="ComboBoxItem_Foreground" Color="{StaticResource SystemColorButtonTextColor}" />
+                    <SolidColorBrush x:Key="ComboBoxItem_Background" Color="{StaticResource SystemControlTransparent}" />
+                    <Thickness x:Key="ComboBoxItem_Padding">11,5,11,7</Thickness>
+                    <CornerRadius x:Key="ComboBoxItem_CornerRadius">3</CornerRadius>
+
+                    --><!--comboboxitem content border properties--><!--
+                    <CornerRadius x:Key="ComboBoxItem_ContentBorder_CornerRadius">4</CornerRadius>
+                    <Thickness x:Key="ComboBoxItem_ContentBorder_Padding">0</Thickness>
+                    <Thickness x:Key="ComboBoxItem_ContentBorder_Margin">3,2,3,0</Thickness>
+                    <VerticalAlignment x:Key="ComboBoxItem_ContentBorder_VerticalAlignment">Stretch</VerticalAlignment>-->
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="HasItemsFalse">
+                    <sys:Double x:Key="DropDownBorder_Height">32</sys:Double>
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="AllowsTransparencyFalse">
+                    <CornerRadius x:Key="DropDownBorder_CornerRadius">0</CornerRadius>
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="IsEditable">
+                    <Visibility x:Key="Textbox_Visibility">Visible</Visibility>
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="Disabled">
+                    <SolidColorBrush x:Key="ContentBorder_Background" Color="{StaticResource SystemColorWindowColor}" />
+                    <!--<SolidColorBrush x:Key="ComboBox_BorderBrush" Color="{StaticResource SystemControlDisabledBaseLow}" />-->
+                    <!--<SolidColorBrush x:Key="ComboBox_Foreground" Color="{StaticResource SystemControlDisabledBaseMediumLow}" />-->
+                    <!--Value is from WPF as winui key is not defined-->
+                    <SolidColorBrush x:Key="ComboBox_Foreground" Color="{StaticResource SystemColorGrayTextColor}" />
+                    <SolidColorBrush x:Key="ContentBorder_BorderBrush" Color="{StaticResource SystemColorWindowColor}" />
+                </ut:TestDictionary>
+
+                <ut:TestDictionary Name="CustomSolidBrush">
+                    <SolidColorBrush x:Key="ComboBox_Background" Color="Aqua" />
+                    <SolidColorBrush x:Key="ComboBox_Foreground" Color="Maroon" />
+                    <!--<SolidColorBrush x:Key="ComboBox_BorderBrush" Color="{StaticResource ControlFillColorTransparent}" />-->
+                </ut:TestDictionary>
+                <ut:TestDictionary Name="Custom">
+                    <Thickness x:Key="ComboBox_BorderThickness">10</Thickness>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalAlignment">Right</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalAlignment">Bottom</VerticalAlignment>
+                    <HorizontalAlignment x:Key="ComboBox_HorizontalContentAlignment">Right</HorizontalAlignment>
+                    <VerticalAlignment x:Key="ComboBox_VerticalContentAlignment">Bottom</VerticalAlignment>
+                    <!--<sys:Double x:Key="ComboBox_MinHeight">32</sys:Double>-->
+                    <sys:Double x:Key="ComboBox_MinWidth">90</sys:Double>
+                    <Thickness x:Key="ComboBox_Padding">20,4,10,10</Thickness>
+                </ut:TestDictionary>
+            </ut:TestDictionary.MergedDictionaries>
+        </ut:TestDictionary>
+    </ResourceDictionary.MergedDictionaries>
+</ResourceDictionary>
\ No newline at end of file
diff --git a/tests/Fluent.UITests/ResourceTests/Data/Dark.Test.xaml b/tests/Fluent.UITests/ResourceTests/Data/Dark.Test.xaml
index 90f5ea3..0f2db14 100644
--- a/tests/Fluent.UITests/ResourceTests/Data/Dark.Test.xaml
+++ b/tests/Fluent.UITests/ResourceTests/Data/Dark.Test.xaml
@@ -86,6 +86,7 @@
 
     <!--  Fallback color for missing Acrylic used for e.g. Flyouts  -->
     <Color x:Key="AcrylicBackgroundFillColorDefault">#2C2C2C</Color>
+    <Color x:Key="AcrylicInAppFillColorDefault">#F9F9F9</Color>
 
     <Color x:Key="LayerOnMicaBaseAltFillColorDefault">#733A3A3A</Color>
     <Color x:Key="LayerOnMicaBaseAltFillColorSecondary">#0FFFFFFF</Color>
@@ -111,6 +112,7 @@
     <Color x:Key="SystemFillColorNeutralBackground">#08FFFFFF</Color>
     <Color x:Key="SystemFillColorSolidAttentionBackground">#2E2E2E</Color>
     <Color x:Key="SystemFillColorSolidNeutralBackground">#2E2E2E</Color>
+    <Color x:Key="SystemControlTransparent">Transparent</Color>
 
     <!-- AccentColor Brushes -->
 
diff --git a/tests/Fluent.UITests/ResourceTests/Data/HC.Test.xaml b/tests/Fluent.UITests/ResourceTests/Data/HC.Test.xaml
index 5161b89..fa8da13 100644
--- a/tests/Fluent.UITests/ResourceTests/Data/HC.Test.xaml
+++ b/tests/Fluent.UITests/ResourceTests/Data/HC.Test.xaml
@@ -103,6 +103,7 @@
     <Color x:Key="SystemFillColorNeutralBackground">#2D3236</Color>
     <Color x:Key="SystemFillColorSolidAttentionBackground">#2D3236</Color>
     <Color x:Key="SystemFillColorSolidNeutralBackground">#FF0000</Color>
+    <Color x:Key="SystemControlTransparent">Transparent</Color>
 
     <DynamicResource x:Key="SystemColorWindowTextColor" ResourceKey="{x:Static SystemColors.WindowTextColorKey}" />
     <DynamicResource x:Key="SystemColorWindowColor" ResourceKey="{x:Static SystemColors.WindowColorKey}" />
diff --git a/tests/Fluent.UITests/ResourceTests/Data/Light.Test.xaml b/tests/Fluent.UITests/ResourceTests/Data/Light.Test.xaml
index 28aca08..58f7811 100644
--- a/tests/Fluent.UITests/ResourceTests/Data/Light.Test.xaml
+++ b/tests/Fluent.UITests/ResourceTests/Data/Light.Test.xaml
@@ -84,6 +84,7 @@
 
     <!--  Fallback color for missing Acrylic used for e.g. Flyouts  -->
     <Color x:Key="AcrylicBackgroundFillColorDefault">#F9F9F9</Color>
+    <Color x:Key="AcrylicInAppFillColorDefault">#F9F9F9</Color>
 
     <Color x:Key="LayerOnMicaBaseAltFillColorDefault">#B3FFFFFF</Color>
     <Color x:Key="LayerOnMicaBaseAltFillColorSecondary">#0A000000</Color>
@@ -109,6 +110,7 @@
     <Color x:Key="SystemFillColorNeutralBackground">#06000000</Color>
     <Color x:Key="SystemFillColorSolidAttentionBackground">#F7F7F7</Color>
     <Color x:Key="SystemFillColorSolidNeutralBackground">#F3F3F3</Color>
+    <Color x:Key="SystemControlTransparent">Transparent</Color>
 
     <DynamicResource x:Key="SystemAccentColor" ResourceKey="{x:Static SystemColors.AccentColorKey}" />
     <DynamicResource x:Key="SystemAccentColorLight1" ResourceKey="{x:Static SystemColors.AccentColorLight1Key}" />