Alright, this doesn't happen always but has happened to me twice already. The symptom is simple, the whole code of a script disappears. It shows a empty window before my eyes in the blink of an eye. Redo doesn't work, there's no way to recover it other than doing it all over from last backup. I've already had issues with GMS2's ridiculous method of managing files "physically" and I suspect this bug is from that but whatever, the point is that it's happened and would happen again. So, is this a known issue?