Mysterious entity introduced by AmbientLight causes warning

[uben0]

I have a main camera and a secondary camera for overlays (like the minimap). But as soon as I attach an AmbientLight to the secondary camera, a warning appears in logs.

// main camera
commands.spawn((
    Player,
    Camera3d::default(),
    Projection::Perspective(PerspectiveProjection {
        fov: 100.0f32.to_radians(),
        ..default()
    }),
    Transform::from_xyz(14.0, 13.5, 12.0),
));

// secondary camera
commands.spawn((
    Transform::from_xyz(0.0, 0.0, 100.0).looking_at(Vec3::ZERO, Vec3::Y),
    Camera3d::default(),
    Camera {
        order: 1,
        clear_color: ClearColorConfig::None,
        ..default()
    },
    RenderLayers::layer(1),
    Projection::Orthographic(OrthographicProjection::default_3d()),
    AmbientLight {
        color: Color::WHITE,
        brightness: 10_000.0,
        ..default()
    },
));

The following message appear:

WARN bevy_render::camera::camera: Entity 5v1 has a `Camera` component, but it doesn't have a render graph configured. Consider adding a `Camera2d` or `Camera3d` component, or manually adding a `CameraRenderGraph` component if you need a custom render graph.

The entity here is not an entity I created myself. It seems to be created after my main camera and before my secondary camera.

If I don't attach an AmbientLight component to my secondary camera, the warning goes away.

commands.spawn((
    Transform::from_xyz(0.0, 0.0, 100.0).looking_at(Vec3::ZERO, Vec3::Y),
    Camera3d::default(),
    Camera {
        order: 1,
        clear_color: ClearColorConfig::None,
        ..default()
    },
    RenderLayers::layer(1),
    Projection::Orthographic(OrthographicProjection::default_3d()),
    // AmbientLight {
    //     color: Color::WHITE,
    //     brightness: 10_000.0,
    //     ..default()
    // },
));

I tried inspecting that mysterious entity with world.inspect_entity(...), but I didn't see anything interesting.

What is going on here?

I also tried to insert AmbientLight after, because it requires Camera. But it didn't change anything.

commands
    .spawn((Camera3d::default(), Transform::default()))
    .insert(AmbientLight::default());

This is the minimal code to reproduce the error.

[uben0]

I found an issue signal my problem #19203