I use my old 3,1 as my main DAW (or, rather, I would be if I ever get around to setting it up), but I'm thinking of maybe using my 4,1 (with 5,1 firmware) instead, since it's basically the same, but faster (it runs all the same software and my Pro Tools DSP cards work in it the same).
I recently discovered Firefox Dynasty too, and I use it on my main Mac desktop which is stuck running Mojave. However, since the original developer apparently went nuts and got himself banned, it's been picked up by a new developer and renamed Momiji. It's also now based on 140 ESR, so it's more stable and predictable.
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