This bar shows the undo history for the current document, as a list of actions. It also provides a precise and conveniently automated way of undoing or redoing to any arbitrary state. To undo/redo to a given state, double-click the corresponding action, or use the cursor keys to select the action and then press Enter. During an undo/redo sequence, a progress dialog for the entire sequence is shown, in addition to any progress dialogs shown by individual actions. To show or hide the bar, use View/More Bars/History Bar.