(04-01-2022, 12:06 PM)GiĀ Nattak Wrote: I'd advise against using a ROM with the .sfc extension for testing or patching etc., that of course stands for Super Famicom, and even if it is in fact the English version that's usually a telltale sign it's going to be the v1.1 ROM.
It depends where you get your ROM from. The NO-INTRO romset, which is a reference set, use the .sfc extension for all its ROMs, so FF3us 1.0, 1.1 and ff6j all have the .sfc extension.