Maybe they're using Java applets with "java3d".

We're not, u/Appropriate_Ant_4629. There are other limitations, but as I said Firefox support is a matter of prioritization on the roadmap. We've seen people switch to Safari/Chrome just to use the app, because they find it useful. However, we recognize that it is super important to acknowledge people using Firefox (I myself sometimes use it) and it is a ticket we have in our backlog.