A bug that Messes with Motion Keyframes I think

Trash pref and reinstall.

never heard of seen this issue.

Motion isn't a Plugin, It's the motion Itself (Positioning and Scaling) It just shut off all of it and the keyframes that I've mad previously are Gone

Might want to do some house keeping first.

Your project is burried in several auto save folders.

Motion might be some plugin you once installed and no longer available.