Fix winit::conversion on Windows

winit/src/conversion.rs

@@ -80,7 +80,7 @@ pub fn window_attributes(
         attributes = attributes
             .with_skip_taskbar(settings.platform_specific.skip_taskbar);
 
-        window_builder = window_builder.with_undecorated_shadow(
+        attributes = attributes.with_undecorated_shadow(
             settings.platform_specific.undecorated_shadow,
         );
     }