I was nudging one control point of a curve. When I pressed U key to undo many small nudges, Rhino 6.3 crashed. I have sent dump file to email@example.com
We think this is related to “standing” on the keyboard, like using Nudge and Undo, not with a few taps, but with prolonged and repeated use.
We do not yet know what’s going on but this seems to be involved.
Until we get it figured out and fixed, avoid “standing” on the keyboard.