Improve Theme.cs

Flow.Launcher/Helper/ErrorReporting.cs

@@ -5,7 +5,7 @@
 using Flow.Launcher.Infrastructure;
 using Flow.Launcher.Infrastructure.Exception;
 using Flow.Launcher.Infrastructure.Logger;
 using NLog;
 
 namespace Flow.Launcher.Helper;
 
@@ -14,7 +14,7 @@
     private static void Report(Exception e, bool silent = false, [CallerMemberName] string methodName = "UnHandledException")
     {
         var logger = LogManager.GetLogger(methodName);
         logger.Fatal(ExceptionFormatter.FormatExcpetion(e));
         if (silent) return;
 
         // Workaround for issue https://github.com/Flow-Launcher/Flow.Launcher/issues/4016
@@ -23,8 +23,14 @@
         // Many bug reports because users see the "Error report UI" after the crash with System.Runtime.InteropServices.COMException 0xD0000701 or 0x80263001.
         // However, displaying this "Error report UI" during WPF crashes, especially when DWM composition is changing, is not ideal; some users reported it hangs for up to a minute before the it appears.
         // This change modifies the behavior to log the exception instead of showing the "Error report UI".
         if (ExceptionHelper.IsRecoverableDwmCompositionException(e)) return;
 
+        // Workaround for a WPF issue where changing the Windows theme or accent color triggers
+        // SystemResources.InvalidateTreeResources, which tries to clone Color values stored in styles
+        // and fails with an InvalidCastException. This is a benign framework-level exception that
+        // does not affect Flow Launcher functionality, so we log it silently instead of showing the error dialog.
+        if (ExceptionHelper.IsRecoverableSystemResourceException(e)) return;
+
         var reportWindow = new ReportWindow(e);
         reportWindow.Show();
     }

Flow.Launcher/Helper/ExceptionHelper.cs

@@ -17,7 +17,7 @@
     /// <summary>
     /// Returns true if the exception is a recoverable DWM composition exception.
     /// </summary>
     internal static bool IsRecoverableDwmCompositionException(Exception exception)
     {
         if (exception is not COMException comException)
         {
@@ -37,6 +37,25 @@
         // Check for common DWM composition changed patterns in the stack trace
         var stackTrace = comException.StackTrace;
         return !string.IsNullOrEmpty(stackTrace) &&
                stackTrace.Contains("DwmCompositionChanged", StringComparison.OrdinalIgnoreCase);
     }
+
+    /// <summary>
+    /// Returns true if the exception is a recoverable WPF system resource invalidation exception
+    /// that occurs when Windows changes its theme or accent colors. This is a known WPF issue where
+    /// <c>Color</c> values stored in styles are incorrectly cloned during resource tree invalidation.
+    /// </summary>
+    internal static bool IsRecoverableSystemResourceException(Exception exception)
+    {
+        if (exception is not InvalidCastException)
+        {
+            return false;
+        }
+
+        // Check for the specific Color-to-Expression cast failure originating from WPF's
+        // SystemResources.InvalidateTreeResources, triggered by Windows theme/accent color changes.
+        var stackTrace = exception.StackTrace;
+        return !string.IsNullOrEmpty(stackTrace) &&
+               stackTrace.Contains("System.Windows.SystemResources.InvalidateTreeResources", StringComparison.Ordinal);
+    }
 }