internal void EnableBlur() { var windowHelper = new WindowInteropHelper(this); var accent = new AccentPolicy(); accent.AccentState = AccentState.ACCENT_ENABLE_BLURBEHIND; var accentStructSize = Marshal.SizeOf(accent); var accentPtr = Marshal.AllocHGlobal(accentStructSize); Marshal.StructureToPtr(accent, accentPtr, false); var data = new WindowCompositionAttributeData(); data.Attribute = WindowCompositionAttribute.WCA_ACCENT_POLICY; data.SizeOfData = accentStructSize; data.Data = accentPtr; SetWindowCompositionAttribute(windowHelper.Handle, ref data); Marshal.FreeHGlobal(accentPtr); }