PLEASE add an undo/redo function

CTRL Z is always undo on almost every windows program. i believe its a similar button on a mac.

I have mouse issues and it sometimes selects all code and deletes it. i'm so afraid its going to permanently delete all my code on a passage and i won't be able to get it back. this is why i save a billion copies of all my stories.

but come on! undo is a simple command!