If this is the experience, no thanks. I stared at a blank screen for about 5 seconds on Firefox mobile before the calculator appeared. Almost gave up.
The native app version of the app generally fares better, even we still have some improvements to make here (the new Android 13 JNI improvements are likely to help us a lot).
Edit: I reloaded right after posting the above, and the gallery loaded immediately as a result. Something's wrong with the loader.
I doubt there's anything you can do. It will probably work fine for corporate intranet sites and back office apps with some aggressive caching.