This seems super bizarre in the face of bsnes. ZSNES as a name nowadays is basically nostalgia bait; base ZSNES – of the popular "big three" of bsnes, SNES-9X, and ZSNES – is the worst SNES emulator you can be using. Meanwhile, bsnes is fantastic (and even, for nostalgia pandering, has the falling snow as an option if that would break the bank).
"Who on Earth asked for this?", is my question. "Classic development style" in the case of ZSNES was shitty, highly inaccurate HLE that worked just well enough for popular titles. It's a honking heap of shit at this point that, in 99.99% of cases, you'd only use because you don't know better. I have no idea what this new version does that's remarkable enough to warrant its existence.