I downloaded ThumbyONE by Austino7116, and it was working perfectly fine, I could emulate ROMs, run Pico-8, and whatever. But I got a ROM for GBCorp, because it looked fun, and when I ran it, it instantly corrupted my filesystem. I can't copy anything back to my PC, I can't re-flash any firmware, and the few Pico-8 carts I copied back have been half deleted, so the bottom half is completely white (I tried attaching a P8 cart for Combo Pool but it won't even attach right its so corrupted). I can't scan/repair from my PC, and the "Defrag FAT" option on the device just crashes it. What the actual heck do I do?!?!
EDIT: I used a universal flash nuke and reflashed the firmware and that worked. If this happens to anybody else, I have a copy of the og thumby color firmware I attached.