>
        (shortcut: C+z) reverses the most recent editing
        command. For example, this can be used to restore unintentionally
        deleted text. More complicated operations, such as a search and replace,
        can also be undone.
If you undo too many changes,
        > (shortcut:
        C+e C+z) can restore the changes again. For example, if
        some text was inserted,  will remove it
        from the buffer.  will insert it
        again.
By default, the last 100 edits is retained; older edits cannot be undone. The maximum number of undos and whether undos are reset when a buffer is saved can be changed in the pane of the > dialog box; see the section called “The Editing Pane”.