This annoys to me to no end. My programming editor has an undo feature (like most software), but I've also set it up to make automatically make 500 backups so if I made a mistake in the past few days I can start over again from a certain point before I starting mucking things up. 500 may sound like a lot, but during software development it's easy to make hundreds of changes daily.

Since there's no undos in the MX-980, I save often and save under a different name. Setup1, Setup2, etc. Not an ideal solution but at least I won't lose most than an hour or so of work.

I wonder if the MX-980 editor was an afterthought? There are so many counter intuitive aspects to the editor, you'd think it was developed in the 80's or outsourced to the lowest bidder overseas.