We provide a timesheet web app. And didn't want save/submit buttons. Auto-saving the data as users type. To alleviate this change for business users, we decid

We provide a timesheet web app. And didn't want save/submit buttons. Auto-saving the data as users type. To alleviate this change for business users, we decided to build an Undo, and a Redo, for most user actions. With a similar technique, by storing the action and it's reverse in 2 stacks. And moving them from one stack to the other. It was quite hard to implement together with an auto-saving of the data. But after 3 years of operations, the undo/redo is barely used. And we get requests from users who clearly didn't see it. Or don't imagine it is possible. While I was really happy seeing it working on a web app. I'm not sure it was worth the effort, and the additional complexity to save data.