I got flustered, and with no answers to this issue I did the Last Resort: Uninstall/Reinstall. And now its rendering in FF and SuperFly both, and I have not touched that scary little button in the Render screen! I dunno, maybe my cat rolled on the keyboard in some way that affected the program. I want to add, P12 has yet to crash no matter what I did to it. Solid as a rock. Which is very cool :o)

My 66th Birthday PC Build (July 1, 2020) :  named BadMoonRYZEN!, W10Pro x64, Octal Core RYZEN7 X3700 4.05 GHz, 64GB DDR4 RAM, GeForce RTX 3060 - 12GB GDDR6, PP2014, PP 11, P12, PS-CS4 Extended & Vue 2024.

McG.