PDF (adobe.com)

Undo mistakes

In Contribute, as in most applications, you can undo individual mistakes as you make them. You can also redo an edit if you decide that you don’t want to undo it.

Note: In Contribute, you can also discard changes, after you publish your draft, by reverting to a previously published version of a page. For more information, see Roll back to a previous version of a page.