Merge 7476cdd894 into 1bdc1164f8

Changed assignment of WindowBorderStyle to use Application.Current.Resources for global effect, replacing previous use of _oldResource. This ensures theme changes are applied consistently across the application.

Flow.Launcher.Core/Resource/Theme.cs

@@ -11,12 +11,12 @@ using System.Windows.Markup;
 using System.Windows.Media;
 using System.Windows.Media.Effects;
 using System.Windows.Shell;
-using System.Windows.Threading;
 using Flow.Launcher.Infrastructure;
 using Flow.Launcher.Infrastructure.UserSettings;
 using Flow.Launcher.Plugin;
 using Flow.Launcher.Plugin.SharedModels;
 using Microsoft.Win32;
+using System.Windows.Threading;
 
 namespace Flow.Launcher.Core.Resource
 {
@@ -100,12 +100,6 @@ namespace Flow.Launcher.Core.Resource
 
         private void UpdateResourceDictionary(ResourceDictionary dictionaryToUpdate)
         {
-            // Add new resources
-            if (!Application.Current.Resources.MergedDictionaries.Contains(dictionaryToUpdate))
-            {
-                Application.Current.Resources.MergedDictionaries.Add(dictionaryToUpdate);
-            }
-
             // Remove old resources
             if (_oldResource != null && _oldResource != dictionaryToUpdate &&
                 Application.Current.Resources.MergedDictionaries.Contains(_oldResource))
@@ -113,7 +107,20 @@ namespace Flow.Launcher.Core.Resource
                 Application.Current.Resources.MergedDictionaries.Remove(_oldResource);
             }
 
-            _oldResource = dictionaryToUpdate;
+            // Add new resources
+            try
+            {
+                if (!Application.Current.Resources.MergedDictionaries.Contains(dictionaryToUpdate))
+                {
+                    Application.Current.Resources.MergedDictionaries.Add(dictionaryToUpdate);
+                }
+                _oldResource = dictionaryToUpdate;
+            }
+            catch (InvalidCastException)
+            {
+                // System.InvalidCastException: Unable to cast object of type 'System.Windows.Media.Color' to type 'System.Windows.Expression'.
+                _oldResource = null;
+            }
         }
 
         /// <summary>
@@ -124,8 +131,8 @@ namespace Flow.Launcher.Core.Resource
             try
             {
                 // Load a ResourceDictionary for the specified theme.
-                var themeName = _settings.Theme;
-                var dict = GetThemeResourceDictionary(themeName);
+                var theme = _settings.Theme;
+                var dict = GetThemeResourceDictionary(theme);
 
                 // Apply font settings to the theme resource.
                 ApplyFontSettings(dict);
@@ -221,7 +228,13 @@ namespace Flow.Launcher.Core.Resource
                 var foregroundPropertyValue = style.Setters.OfType<Setter>().Where(x => x.Property.Name == "Foreground")
                     .Select(x => x.Value).FirstOrDefault();
                 if (!caretBrushPropertyValue && foregroundPropertyValue != null)
-                    style.Setters.Add(new Setter(TextBoxBase.CaretBrushProperty, foregroundPropertyValue));
+                {
+                    var newCaretValue = GetNewCaretValue(foregroundPropertyValue);
+                    if (newCaretValue != null)
+                    {
+                        style.Setters.Add(new Setter(TextBoxBase.CaretBrushProperty, newCaretValue));
+                    }
+                }
             }
             else
             {
@@ -246,6 +259,37 @@ namespace Flow.Launcher.Core.Resource
             }
         }
 
+        private static object GetNewCaretValue(object foregroundPropertyValue)
+        {
+            object newCaretValue;
+            if (foregroundPropertyValue is DynamicResourceExtension dynamicResource)
+            {
+                newCaretValue = new DynamicResourceExtension(dynamicResource.ResourceKey);
+            }
+            else if (foregroundPropertyValue is SolidColorBrush solidBrush)
+            {
+                // Create a new brush to avoid sharing mutable freezables with potential expressions
+                if (solidBrush.IsFrozen)
+                {
+                    newCaretValue = solidBrush;
+                }
+                else
+                {
+                    var newBrush = new SolidColorBrush(solidBrush.Color)
+                    {
+                        Opacity = solidBrush.Opacity
+                    };
+                    if (newBrush.CanFreeze) newBrush.Freeze();
+                    newCaretValue = newBrush;
+                }
+            }
+            else
+            {
+                newCaretValue = foregroundPropertyValue;
+            }
+            return newCaretValue;
+        }
+
         private ResourceDictionary GetThemeResourceDictionary(string theme)
         {
             var uri = GetThemePath(theme);
@@ -275,10 +319,15 @@ namespace Flow.Launcher.Core.Resource
                 queryBoxStyle.Setters.Add(new Setter(Control.FontStretchProperty, fontStretch));
 
                 var caretBrushPropertyValue = queryBoxStyle.Setters.OfType<Setter>().Any(x => x.Property.Name == "CaretBrush");
-                var foregroundPropertyValue = queryBoxStyle.Setters.OfType<Setter>().Where(x => x.Property.Name == "Foreground")
-                    .Select(x => x.Value).FirstOrDefault();
+                var foregroundPropertyValue = queryBoxStyle.Setters.OfType<Setter>().FirstOrDefault(x => x.Property.Name == "Foreground")?.Value;
                 if (!caretBrushPropertyValue && foregroundPropertyValue != null) //otherwise BaseQueryBoxStyle will handle styling
-                    queryBoxStyle.Setters.Add(new Setter(TextBoxBase.CaretBrushProperty, foregroundPropertyValue));
+                {
+                    var newCaretValue = GetNewCaretValue(foregroundPropertyValue);
+                    if (newCaretValue != null)
+                    {
+                        queryBoxStyle.Setters.Add(new Setter(TextBoxBase.CaretBrushProperty, newCaretValue));
+                    }
+                }
 
                 // Query suggestion box's font style is aligned with query box
                 querySuggestionBoxStyle.Setters.Add(new Setter(Control.FontFamilyProperty, fontFamily));
@@ -419,20 +468,17 @@ namespace Flow.Launcher.Core.Resource
                 if (string.IsNullOrEmpty(path))
                     throw new DirectoryNotFoundException($"Theme path can't be found <{path}>");
 
-                // Retrieve theme resource – always use the resource with font settings applied.
-                var resourceDict = GetResourceDictionary(theme);
-
-                UpdateResourceDictionary(resourceDict);
-
                 _settings.Theme = theme;
 
-                //always allow re-loading default theme, in case of failure of switching to a new theme from default theme
+                // Always allow re-loading default theme, in case of failure of switching to a new theme from default theme
                 if (_oldTheme != theme || theme == Constant.DefaultTheme)
                 {
                     _oldTheme = Path.GetFileNameWithoutExtension(_oldResource.Source.AbsolutePath);
                 }
 
-                BlurEnabled = IsBlurTheme();
+                // Check if blur is enabled
+                var dict = GetThemeResourceDictionary(theme);
+                BlurEnabled = Win32Helper.IsBackdropSupported() && IsThemeBlurEnabled(dict);
 
                 // Apply blur and drop shadow effect so that we do not need to call it again
                 _ = RefreshFrameAsync();
@@ -477,11 +523,58 @@ namespace Flow.Launcher.Core.Resource
 
         public void AddDropShadowEffectToCurrentTheme()
         {
-            var dict = GetCurrentResourceDictionary();
+            // Get current theme's WindowBorderStyle
+            var theme = _settings.Theme;
+            var dict = GetThemeResourceDictionary(theme);
+            var windowBorderStyle = dict.Contains("WindowBorderStyle") ? dict["WindowBorderStyle"] as Style : null;
+            if (windowBorderStyle == null) return;
 
-            var windowBorderStyle = dict["WindowBorderStyle"] as Style;
+            // Get a new unsealed style based on the old one, and copy Resources and Triggers
+            var newWindowBorderStyle = new Style(typeof(Border));
+            CopyStyle(windowBorderStyle, newWindowBorderStyle);
 
-            var effectSetter = new Setter
+            // Identify existing Margin to calculate new Margin, and copy other setters
+            Setter existingMarginSetter = null;
+            foreach (var setterBase in windowBorderStyle.Setters)
+            {
+                if (setterBase is Setter setter)
+                {
+                    // Skip existing Margin (we'll replace it)
+                    if (setter.Property == FrameworkElement.MarginProperty)
+                    {
+                        existingMarginSetter = setter;
+                        continue;
+                    }
+
+                    // Skip existing Effect (we'll ensure strictly one is added)
+                    if (setter.Property == UIElement.EffectProperty) continue;
+                }
+
+                // Add other setters (e.g. Background, BorderThickness)
+                newWindowBorderStyle.Setters.Add(setterBase);
+            }
+
+            // Calculate new Margin
+            Thickness newMargin;
+            if (existingMarginSetter == null)
+            {
+                newMargin = new Thickness(ShadowExtraMargin, 12, ShadowExtraMargin, ShadowExtraMargin);
+            }
+            else
+            {
+                var baseMargin = (Thickness)existingMarginSetter.Value;
+                newMargin = new Thickness(
+                    baseMargin.Left + ShadowExtraMargin,
+                    baseMargin.Top + ShadowExtraMargin,
+                    baseMargin.Right + ShadowExtraMargin,
+                    baseMargin.Bottom + ShadowExtraMargin);
+            }
+
+            // Add new Margin Setter
+            newWindowBorderStyle.Setters.Add(new Setter(FrameworkElement.MarginProperty, newMargin));
+
+            // Add Drop Shadow Effect Setter
+            newWindowBorderStyle.Setters.Add(new Setter
             {
                 Property = UIElement.EffectProperty,
                 Value = new DropShadowEffect
@@ -491,62 +584,52 @@ namespace Flow.Launcher.Core.Resource
                     Direction = 270,
                     BlurRadius = 30
                 }
-            };
+            });
 
-            if (windowBorderStyle.Setters.FirstOrDefault(setterBase => setterBase is Setter setter && setter.Property == FrameworkElement.MarginProperty) is not Setter marginSetter)
-            {
-                var margin = new Thickness(ShadowExtraMargin, 12, ShadowExtraMargin, ShadowExtraMargin);
-                marginSetter = new Setter()
-                {
-                    Property = FrameworkElement.MarginProperty,
-                    Value = margin,
-                };
-                windowBorderStyle.Setters.Add(marginSetter);
+            SetResizeBoarderThickness(newMargin);
 
-                SetResizeBoarderThickness(margin);
-            }
-            else
-            {
-                var baseMargin = (Thickness)marginSetter.Value;
-                var newMargin = new Thickness(
-                    baseMargin.Left + ShadowExtraMargin,
-                    baseMargin.Top + ShadowExtraMargin,
-                    baseMargin.Right + ShadowExtraMargin,
-                    baseMargin.Bottom + ShadowExtraMargin);
-                marginSetter.Value = newMargin;
-
-                SetResizeBoarderThickness(newMargin);
-            }
-
-            windowBorderStyle.Setters.Add(effectSetter);
-
-            UpdateResourceDictionary(dict);
+            Application.Current.Resources["WindowBorderStyle"] = newWindowBorderStyle;
         }
 
         public void RemoveDropShadowEffectFromCurrentTheme()
         {
-            var dict = GetCurrentResourceDictionary();
-            var windowBorderStyle = dict["WindowBorderStyle"] as Style;
+            // Get current theme's WindowBorderStyle
+            var theme = _settings.Theme;
+            var dict = GetThemeResourceDictionary(theme);
+            var windowBorderStyle = dict.Contains("WindowBorderStyle") ? dict["WindowBorderStyle"] as Style : null;
+            if (windowBorderStyle == null) return;
 
-            if (windowBorderStyle.Setters.FirstOrDefault(setterBase => setterBase is Setter setter && setter.Property == UIElement.EffectProperty) is Setter effectSetter)
-            {
-                windowBorderStyle.Setters.Remove(effectSetter);
-            }
+            // Get a new unsealed style based on the old one, and copy Resources and Triggers
+            var newWindowBorderStyle = new Style(typeof(Border));
+            CopyStyle(windowBorderStyle, newWindowBorderStyle);
 
-            if (windowBorderStyle.Setters.FirstOrDefault(setterBase => setterBase is Setter setter && setter.Property == FrameworkElement.MarginProperty) is Setter marginSetter)
+            // Copy Setters, excluding the Effect setter and updating the Margin setter
+            foreach (var setterBase in windowBorderStyle.Setters)
             {
-                var currentMargin = (Thickness)marginSetter.Value;
-                var newMargin = new Thickness(
-                    currentMargin.Left - ShadowExtraMargin,
-                    currentMargin.Top - ShadowExtraMargin,
-                    currentMargin.Right - ShadowExtraMargin,
-                    currentMargin.Bottom - ShadowExtraMargin);
-                marginSetter.Value = newMargin;
+                if (setterBase is Setter setter)
+                {
+                    // Skip existing Effect (We'll remove it)
+                    if (setter.Property == UIElement.EffectProperty) continue;
+
+                    // Update Margin by subtracting the extra margin we added for the shadow
+                    if (setter.Property == FrameworkElement.MarginProperty)
+                    {
+                        var currentMargin = (Thickness)setter.Value;
+                        var newMargin = new Thickness(
+                            currentMargin.Left - ShadowExtraMargin,
+                            currentMargin.Top - ShadowExtraMargin,
+                            currentMargin.Right - ShadowExtraMargin,
+                            currentMargin.Bottom - ShadowExtraMargin);
+                        newWindowBorderStyle.Setters.Add(new Setter(FrameworkElement.MarginProperty, newMargin));
+                        continue;
+                    }
+                }
+                newWindowBorderStyle.Setters.Add(setterBase);
             }
 
             SetResizeBoarderThickness(null);
 
-            UpdateResourceDictionary(dict);
+            Application.Current.Resources["WindowBorderStyle"] = newWindowBorderStyle;
         }
 
         public void SetResizeBorderThickness(WindowChrome windowChrome, bool fixedWindowSize)
@@ -596,26 +679,33 @@ namespace Flow.Launcher.Core.Resource
         /// </summary>
         public async Task RefreshFrameAsync()
         {
-            await Application.Current.Dispatcher.InvokeAsync(() =>
+            if (Application.Current == null) return;
+            if (!Application.Current.Dispatcher.CheckAccess())
             {
-                // Get the actual backdrop type and drop shadow effect settings
-                var (backdropType, useDropShadowEffect) = GetActualValue();
+                await Application.Current?.Dispatcher.InvokeAsync(RefreshFrameAsync, DispatcherPriority.Render);
+                return;
+            }
 
-                // Remove OS minimizing/maximizing animation
-                // Methods.SetWindowAttribute(new WindowInteropHelper(mainWindow).Handle, DWMWINDOWATTRIBUTE.DWMWA_TRANSITIONS_FORCEDISABLED, 3);
+            // Get the actual backdrop type and drop shadow effect settings
+            var (backdropType, useDropShadowEffect) = GetActualValue();
 
-                // The timing of adding the shadow effect should vary depending on whether the theme is transparent.
-                if (BlurEnabled)
-                {
-                    AutoDropShadow(useDropShadowEffect);
-                }
-                SetBlurForWindow(_settings.Theme, backdropType);
+            // Remove OS minimizing/maximizing animation
+            // Methods.SetWindowAttribute(new WindowInteropHelper(mainWindow).Handle, DWMWINDOWATTRIBUTE.DWMWA_TRANSITIONS_FORCEDISABLED, 3);
 
-                if (!BlurEnabled)
-                {
-                    AutoDropShadow(useDropShadowEffect);
-                }
-            }, DispatcherPriority.Render);
+            // The timing of adding the shadow effect should vary depending on whether the theme is transparent.
+            if (BlurEnabled)
+            {
+                AutoDropShadow(useDropShadowEffect);
+            }
+
+#pragma warning disable VSTHRD103 // Call async methods when in an async method
+            SetBlurForWindow(_settings.Theme, backdropType);
+#pragma warning restore VSTHRD103 // Call async methods when in an async method
+
+            if (!BlurEnabled)
+            {
+                AutoDropShadow(useDropShadowEffect);
+            }
         }
 
         /// <summary>
@@ -623,13 +713,17 @@ namespace Flow.Launcher.Core.Resource
         /// </summary>
         public async Task SetBlurForWindowAsync()
         {
-            await Application.Current.Dispatcher.InvokeAsync(() =>
+            if (Application.Current == null) return;
+            if (!Application.Current.Dispatcher.CheckAccess())
             {
-                // Get the actual backdrop type and drop shadow effect settings
-                var (backdropType, _) = GetActualValue();
+                await Application.Current?.Dispatcher.InvokeAsync(SetBlurForWindowAsync, DispatcherPriority.Render);
+                return;
+            }
 
-                SetBlurForWindow(_settings.Theme, backdropType);
-            }, DispatcherPriority.Render);
+            // Get the actual backdrop type and drop shadow effect settings
+            var (backdropType, _) = GetActualValue();
+
+            SetBlurForWindow(_settings.Theme, backdropType);
         }
 
         /// <summary>
@@ -667,21 +761,25 @@ namespace Flow.Launcher.Core.Resource
             if (mainWindow == null) return;
 
             // Check if the theme supports blur
-            bool hasBlur = dict.Contains("ThemeBlurEnabled") && dict["ThemeBlurEnabled"] is bool b && b;
+            var hasBlur = IsThemeBlurEnabled(dict);
             if (BlurEnabled && hasBlur && Win32Helper.IsBackdropSupported())
             {
                 // If the BackdropType is Mica or MicaAlt, set the windowborderstyle's background to transparent
                 if (backdropType == BackdropTypes.Mica || backdropType == BackdropTypes.MicaAlt)
                 {
                     windowBorderStyle.Setters.Remove(windowBorderStyle.Setters.OfType<Setter>().FirstOrDefault(x => x.Property.Name == "Background"));
-                    windowBorderStyle.Setters.Add(new Setter(Border.BackgroundProperty, new SolidColorBrush(Color.FromArgb(1, 0, 0, 0))));
+                    var brush = new SolidColorBrush(Color.FromArgb(1, 0, 0, 0));
+                    brush.Freeze();
+                    windowBorderStyle.Setters.Add(new Setter(Border.BackgroundProperty, brush));
                 }
                 else if (backdropType == BackdropTypes.Acrylic)
                 {
                     windowBorderStyle.Setters.Remove(windowBorderStyle.Setters.OfType<Setter>().FirstOrDefault(x => x.Property.Name == "Background"));
-                    windowBorderStyle.Setters.Add(new Setter(Border.BackgroundProperty, new SolidColorBrush(Colors.Transparent)));
+                    var brush = new SolidColorBrush(Colors.Transparent);
+                    brush.Freeze();
+                    windowBorderStyle.Setters.Add(new Setter(Border.BackgroundProperty, brush));
                 }
-                
+
                 // For themes with blur enabled, the window border is rendered by the system, so it's treated as a simple rectangle regardless of thickness.
                 //(This is to avoid issues when the window is forcibly changed to a rectangular shape during snap scenarios.)
                 var cornerRadiusSetter = windowBorderStyle.Setters.OfType<Setter>().FirstOrDefault(x => x.Property == Border.CornerRadiusProperty);
@@ -689,7 +787,7 @@ namespace Flow.Launcher.Core.Resource
                     cornerRadiusSetter.Value = new CornerRadius(0);
                 else
                     windowBorderStyle.Setters.Add(new Setter(Border.CornerRadiusProperty, new CornerRadius(0)));
-                
+
                 // Apply the blur effect
                 Win32Helper.DWMSetBackdropForWindow(mainWindow, backdropType);
                 ColorizeWindow(theme, backdropType);
@@ -706,13 +804,12 @@ namespace Flow.Launcher.Core.Resource
 
         private void AutoDropShadow(bool useDropShadowEffect)
         {
-            SetWindowCornerPreference("Default");
-            RemoveDropShadowEffectFromCurrentTheme();
             if (useDropShadowEffect)
             {
                 if (BlurEnabled && Win32Helper.IsBackdropSupported())
                 {
                     SetWindowCornerPreference("Round");
+                    RemoveDropShadowEffectFromCurrentTheme();
                 }
                 else
                 {
@@ -725,9 +822,11 @@ namespace Flow.Launcher.Core.Resource
                 if (BlurEnabled && Win32Helper.IsBackdropSupported())
                 {
                     SetWindowCornerPreference("Default");
+                    RemoveDropShadowEffectFromCurrentTheme();
                 }
                 else
                 {
+                    SetWindowCornerPreference("Default");
                     RemoveDropShadowEffectFromCurrentTheme();
                 }
             }
@@ -746,8 +845,9 @@ namespace Flow.Launcher.Core.Resource
         // for theme has not "LightBG" or "DarkBG" case.
         private Color GetWindowBorderStyleBackground(string theme)
         {
-            var Resources = GetThemeResourceDictionary(theme);
-            var windowBorderStyle = (Style)Resources["WindowBorderStyle"];
+            var dict = GetThemeResourceDictionary(theme);
+            var windowBorderStyle = dict.Contains("WindowBorderStyle") ? dict["WindowBorderStyle"] as Style : null;
+            if (windowBorderStyle == null) return Colors.Transparent; // Default is transparent
 
             var backgroundSetter = windowBorderStyle.Setters
                 .OfType<Setter>()
@@ -765,12 +865,12 @@ namespace Flow.Launcher.Core.Resource
                 else if (backgroundValue is DynamicResourceExtension dynamicResource)
                 {
                     // When DynamicResource Extension it is, Key is resource's name.
-                    var resourceKey = backgroundSetter.Value.ToString();
+                    var resourceKey = dynamicResource.ResourceKey.ToString();
 
                     // find key in resource and return color.
-                    if (Resources.Contains(resourceKey))
+                    if (dict.Contains(resourceKey))
                     {
-                        var colorResource = Resources[resourceKey];
+                        var colorResource = dict[resourceKey];
                         if (colorResource is SolidColorBrush colorBrush)
                         {
                             return colorBrush.Color;
@@ -803,7 +903,9 @@ namespace Flow.Launcher.Core.Resource
 
             // Apply background color (remove transparency in color)
             Color backgroundColor = Color.FromRgb(bgColor.Value.R, bgColor.Value.G, bgColor.Value.B);
-            previewStyle.Setters.Add(new Setter(Border.BackgroundProperty, new SolidColorBrush(backgroundColor)));
+            var brush = new SolidColorBrush(backgroundColor);
+            brush.Freeze();
+            previewStyle.Setters.Add(new Setter(Border.BackgroundProperty, brush));
 
             // The blur theme keeps the corner round fixed (applying DWM code to modify it causes rendering issues).
             // The non-blur theme retains the previously set WindowBorderStyle.
@@ -817,7 +919,7 @@ namespace Flow.Launcher.Core.Resource
             Application.Current.Resources["PreviewWindowBorderStyle"] = previewStyle;
         }
 
-        private void CopyStyle(Style originalStyle, Style targetStyle)
+        private static void CopyStyle(Style originalStyle, Style targetStyle)
         {
             // If the style is based on another style, copy the base style first
             if (originalStyle.BasedOn != null)
@@ -841,20 +943,16 @@ namespace Flow.Launcher.Core.Resource
             if (mainWindow == null) return;
 
             // Check if the theme supports blur
-            bool hasBlur = dict.Contains("ThemeBlurEnabled") && dict["ThemeBlurEnabled"] is bool b && b;
+            var hasBlur = IsThemeBlurEnabled(dict);
 
             // SystemBG value check (Auto, Light, Dark)
-            string systemBG = dict.Contains("SystemBG") ? dict["SystemBG"] as string : "Auto"; // 기본값 Auto
+            var systemBG = dict.Contains("SystemBG") ? dict["SystemBG"] as string : "Auto"; // 기본값 Auto
 
             // Check the user's ColorScheme setting
-            string colorScheme = _settings.ColorScheme;
-
-            // Check system dark mode setting (read AppsUseLightTheme value)
-            int themeValue = (int)Registry.GetValue(@"HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Themes\Personalize", "AppsUseLightTheme", 1);
-            bool isSystemDark = themeValue == 0;
+            var colorScheme = _settings.ColorScheme;
 
             // Final decision on whether to use dark mode
-            bool useDarkMode = false;
+            var useDarkMode = false;
 
             // If systemBG is not "Auto", prioritize it over ColorScheme and set the mode based on systemBG value
             if (systemBG == "Dark")
@@ -869,11 +967,20 @@ namespace Flow.Launcher.Core.Resource
             {
                 // If systemBG is "Auto", decide based on ColorScheme
                 if (colorScheme == "Dark")
+                {
                     useDarkMode = true;
+                }
                 else if (colorScheme == "Light")
+                {
                     useDarkMode = false;
+                }
                 else
+                {
+                    // Check system dark mode setting (read AppsUseLightTheme value)
+                    var themeValue = (int)Registry.GetValue(@"HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Themes\Personalize", "AppsUseLightTheme", 1);
+                    var isSystemDark = themeValue == 0;
                     useDarkMode = isSystemDark;  // Auto (based on system setting)
+                }
             }
 
             // Apply DWM Dark Mode
@@ -906,8 +1013,8 @@ namespace Flow.Launcher.Core.Resource
             Color selectedBG = useDarkMode ? DarkBG : LightBG;
             ApplyPreviewBackground(selectedBG);
 
-            bool isBlurAvailable = hasBlur && Win32Helper.IsBackdropSupported(); // Windows 11 미만이면 hasBlur를 강제 false
-
+            // If Windows does not support backdrop, treat as blur unavailable
+            var isBlurAvailable = hasBlur && Win32Helper.IsBackdropSupported();
             if (!isBlurAvailable)
             {
                 mainWindow.Background = Brushes.Transparent;
@@ -917,23 +1024,22 @@ namespace Flow.Launcher.Core.Resource
                 // Only set the background to transparent if the theme supports blur
                 if (backdropType == BackdropTypes.Mica || backdropType == BackdropTypes.MicaAlt)
                 {
-                    mainWindow.Background = new SolidColorBrush(Color.FromArgb(1, 0, 0, 0));
+                    var backgroundBrush = new SolidColorBrush(Color.FromArgb(1, 0, 0, 0));
+                    backgroundBrush.Freeze();
+                    mainWindow.Background = backgroundBrush;
                 }
                 else
                 {
-                    mainWindow.Background = new SolidColorBrush(selectedBG);
+                    var backgroundBrush = new SolidColorBrush(selectedBG);
+                    backgroundBrush.Freeze();
+                    mainWindow.Background = backgroundBrush;
                 }
             }
         }
 
-        private static bool IsBlurTheme()
+        private static bool IsThemeBlurEnabled(ResourceDictionary dict)
         {
-            if (!Win32Helper.IsBackdropSupported()) // Windows 11 미만이면 무조건 false
-                return false;
-
-            var resource = Application.Current.TryFindResource("ThemeBlurEnabled");
-
-            return resource is bool b && b;
+            return dict.Contains("ThemeBlurEnabled") && dict["ThemeBlurEnabled"] is bool enabled && enabled;
         }
 
         #endregion