If you have a keyboard, and just want to undo the most recent change, try pressing Ctrl-Z. To redo a change just undone, Ctrl-Shift-Z.

More Detail on Recent Actions

Otherwise, switch to the ‘Action’ context. The Hex Button will now be flanked by Undo and Redo buttons.

The context pane shows a timeline of the actions performed since initially entering a playpen. Selecting a point in the timeline will return concepts, links, and series to how they were set (see caveats below) at that point.

Note that moves through the timeline are the same as consecutive undo or redo actions. If you only intend to peek at an different ’time’ without changing anything, be sure to select the original place in the timeline when you’re finished.

Resetting Concept Positions

The button below the timeline allows resetting concepts to where they were on the canvas at the time of the playpen’s last save.

When nothing is selected, the button acts on all moved concepts. Otherwise it only resets any selected concepts that have been moved.

Some changes can’t be directly undone

E.g.:

• If a concept is moved to a different location on the canvas, the undo button will not move it back.
• Visibility changes are only temporary and do not change the playpen itself, so are similarly unaffected by undo.
• Changes to the playpen’s name or privacy, if they should be undone, must be overridden instead.