is still good.
                    console.log("Loading app from service worker.");
                    loadMainDartJs();
                }
            });

            // If service worker doesn't succeed in a reasonable amount of time,
            // fallback to plaint <script> tag.
            setTimeout(() => {
                if (!scriptLoaded) {
                    console.warn(
                        "Failed to load app from service worker. Falling back to plain <script> tag."
                    );