I've already wrote it in another topic. It's the unlimited rogue stealth option. Just don't use it.
I have run into the same thing after using the item edit. I tested by running the trainer and then casting fireball on my party. Most of the older options like unlimited items or instant cooldown won't trigger the perma glitch, but it seems newer ones will. I would avoid those for now (anything below unlimited items on the trainer's list of options) because once you do trigger the glitch, you have to exit the game and reload or else all effects become permanent on your characters.