Function process_output_system 

pub fn process_output_system(
    commands: Commands<'_, '_>,
    context_query: Query<'_, '_, (Entity, &mut EguiContext, &mut EguiFullOutput, &mut EguiRenderOutput, &mut EguiOutput, &EguiContextSettings)>,
    request_redraw_writer: MessageWriter<'_, RequestRedraw>,
    last_cursor_icon: Local<'_, HashMap<Entity, CursorIcon>>,
    egui_global_settings: Res<'_, EguiGlobalSettings>,
    window_to_egui_context_map: Res<'_, WindowToEguiContextMap>,
)

Reads Egui output.