DOES NOT WARK BECAUSE OF FLICKERING; Top left origin with pixel-perfect scaling in 2D in Bevy

bevy_top_left.rs

fn setup(mut commands: Commands) {
    let mut camera = OrthographicCameraBundle::new_2d();
    camera.orthographic_projection.window_origin = WindowOrigin::BottomLeft;
    camera.orthographic_projection.scaling_mode = ScalingMode::WindowSize;

    commands.spawn(camera);
}

fn top_left_origin(
    windows: Res<Windows>,
    mut transforms: Query<&mut Transform, (Changed<Transform>, Without<Camera>)>,
) {
    let window = windows.get_primary().unwrap();
    for mut transform in transforms.iter_mut() {
        transform.translation.y = window.height() - transform.translation.y;
    }
}

fn main() {
    App::build()
        .add_plugins(DefaultPlugins)
        .add_startup_system(setup.system())
        .add_system_to_stage(CoreStage::PostUpdate, top_left_origin.system())
        .run();
}