async def METHOD_NAME(app: web.Application) -> None:
    """
    Currently the static resources are contain 4 folders: osparc, s4l, s4llite, tis
    each of them contain and index.html to be served to as the root of the site
    for each type of frontend.
    Caching these 4 items on start
    """
    settings: StaticWebserverModuleSettings = get_plugin_settings(app)
    cached_indexes: dict[str, str] = {}
    session: ClientSession = get_client_session(app)
    for frontend_name in FRONTEND_APPS_AVAILABLE:
        url = URL(settings.STATIC_WEBSERVER_URL) / frontend_name
        _logger.info("Fetching index from %s", url)
        try:
            body = ""
            # web-static server might still not be up
            async for attempt in AsyncRetrying(
                **_STATIC_WEBSERVER_RETRY_ON_STARTUP_POLICY
            ):
                with attempt:
                    response = await session.get(url, raise_for_status=True)
                    body = await response.text()
        except ClientError as err:
            _logger.error("Could not fetch index from static server: %s", err)
            # ANE: Yes this is supposed to fail the boot process
            raise RuntimeError(
                f"Could not fetch index at {str(url)}. Stopping application boot"
            ) from err
        # fixes relative paths
        body = body.replace(f"../resource/{frontend_name}", f"resource/{frontend_name}")
        body = body.replace("boot.js", f"{frontend_name}/boot.js")
        _logger.info("Storing index for %s", url)
        cached_indexes[frontend_name] = body
    app[APP_FRONTEND_CACHED_INDEXES_KEY] = cached_indexes