pub(crate) fn create_constellation(
user_agent: Cow<'static, str>,
config_dir: Option<PathBuf>,
embedder_proxy: EmbedderProxy,
compositor_proxy: CompositorProxy,
time_profiler_chan: ProfilerChan,
mem_profiler_chan: ProfilerChan,
devtools_sender: Option<Sender<DevtoolsControlMsg>>,
webrender_document: DocumentId,
webrender_api_sender: RenderApiSender,
webxr_registry: Registry,
player_context: WindowGLContext,
webgl_threads: Option<WebGLThreads>,
glplayer_threads: Option<GLPlayerThreads>,
initial_window_size: WindowSizeData,
external_images: Arc<Mutex<WebrenderExternalImageRegistry>>,
wgpu_image_map: WGPUImageMap,
protocols: ProtocolRegistry,
) -> Sender<ConstellationMsg>