I'm on a Fairphone 4 using Firefox Mobile. Probably not the most common use case, but it looked like things were failing and I nearly gave up. I'd recommend keeping a few not-cutting-edge CPU devices around and run them with both Chrome and Firefox.
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.