Window transparency does not work under Windows

Is your issue REALLY a bug?

[X] My issue is indeed a bug!
[X] I am not crazy! I will not fill out this form just to ask a question or request a feature. Pinky promise.

Is there an existing issue for this?

[X] I have searched the existing issues.

Is this issue related to iced?

[X] My hardware is compatible and my graphics drivers are up-to-date.

What happened?

Window transparent background does not work, it renders as solid black color, under Windows11. Setting wgpu in features changes nothing. Note: My gpu is an Nvidia card 4070, driver uptodate

Test program: Cargo.toml

[package]
name = "transparency"
version = "0.1.0"
edition = "2021"

[dependencies]
iced = { version = "0.12", features = ["wgpu", "debug"] }

main.rs

use iced::theme::Palette;
use iced::widget::container;
use iced::window::Level;
use iced::{
    executor, mouse, Application, Color, Command, Element, Length, Rectangle, Renderer, Sandbox,
    Settings, Size, Theme,
};

pub fn main() -> iced::Result {
    let settings = Settings {
        id: Some("test".into()),
        window: iced::window::Settings {
            size: Size::new(200f32, 200f32),
            transparent: true,
            level: Level::AlwaysOnTop,
            ..iced::window::Settings::default()
        },
        antialiasing: true,
        ..Settings::default()
    };
    TestApp::run(settings)
}

struct TestApp {
    theme: Theme,
}

#[derive(Debug, Clone, Copy)]
enum Message {}

impl Application for TestApp {
    type Executor = executor::Default;
    type Flags = ();
    type Message = Message;
    type Theme = Theme;

    fn new(_flags: ()) -> (TestApp, Command<Self::Message>) {
        (
            TestApp {
                theme: Theme::custom(
                    "main".to_string(),
                    Palette {
                        background: Color::TRANSPARENT,
                        ..Theme::default().palette()
                    },
                ),
            },
            Command::none(),
        )
    }

    fn title(&self) -> String {
        String::from("test")
    }

    fn update(&mut self, _message: Self::Message) -> Command<Self::Message> {
        Command::none()
    }

    fn view(&self) -> Element<Self::Message> {
        container("1234")
            .height(Length::Fill)
            .center_x()
            .center_y()
            .into()
    }

    fn theme(&self) -> Theme {
        self.theme.clone()
    }
}

What is the expected behavior?

Window transparency should work

Version

crates.io release

Operating System

Windows

Do you have any log output?

No response

iced-rs / iced

Window transparency does not work under Windows #2525